:root {
  --ink: #16202a;
  --muted: #63707d;
  --paper: #fbfaf6;
  --white: #ffffff;
  --navy: #17324d;
  --navy-2: #244b70;
  --accent: #e6a833;
  --accent-soft: #fff2d1;
  --line: #dfe4e8;
  --soft: #f1f5f7;
  --success: #26815f;
  --danger: #b34747;
  --shadow: 0 18px 50px rgba(24, 50, 75, .10);
  --radius: 18px;
}

* { box-sizing: border-box; }

html {
  scroll-behavior: smooth;
  background: var(--paper);
}

body {
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: Inter, ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  line-height: 1.55;
}

a { color: inherit; text-decoration: none; }
img { display: block; max-width: 100%; }
button, input, select { font: inherit; }

.container {
  width: min(1180px, calc(100% - 32px));
  margin: 0 auto;
}

.container.narrow { width: min(820px, calc(100% - 32px)); }

.site-header {
  position: sticky;
  top: 0;
  z-index: 30;
  border-bottom: 1px solid rgba(255,255,255,.12);
  color: white;
  background: rgba(23, 50, 77, .96);
  backdrop-filter: blur(12px);
}

.header-inner {
  min-height: 72px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
}

.brand-mark {
  width: 42px;
  height: 42px;
  display: block;
  object-fit: cover;
  object-position: center 28%;
  border-radius: 50%;
  border: 2px solid rgba(239,176,47,.80);
  background: var(--accent);
  box-shadow: 0 8px 22px rgba(0,0,0,.18);
}

.brand strong,
.brand small { display: block; }

.brand strong { font-size: 17px; letter-spacing: .01em; }
.brand small { color: rgba(255,255,255,.70); font-size: 12px; }

.main-nav {
  display: flex;
  align-items: center;
  gap: 24px;
  font-size: 14px;
  font-weight: 650;
}

.main-nav a {
  color: rgba(255,255,255,.86);
  transition: color .2s ease;
}

.main-nav a:hover { color: var(--accent); }

.menu-toggle {
  display: none;
  border: 0;
  color: white;
  background: transparent;
  font-size: 26px;
  cursor: pointer;
}

.hero,
.page-hero {
  color: white;
  background:
    radial-gradient(circle at 83% 20%, rgba(230,168,51,.28), transparent 26%),
    linear-gradient(145deg, #17324d 0%, #1f466b 60%, #18344f 100%);
}

.hero { padding: 86px 0 74px; }
.page-hero { padding: 76px 0; }
.page-hero.compact { padding: 52px 0; }

.hero-grid {
  display: grid;
  grid-template-columns: 1.12fr .88fr;
  align-items: center;
  gap: 64px;
}

.eyebrow {
  display: inline-block;
  color: var(--accent);
  font-size: 12px;
  font-weight: 800;
  letter-spacing: .13em;
  text-transform: uppercase;
}

.hero h1,
.page-hero h1 {
  max-width: 860px;
  margin: 14px 0 18px;
  font-family: Georgia, "Times New Roman", serif;
  line-height: 1.08;
}

.hero h1 { font-size: clamp(42px, 6vw, 72px); }
.page-hero h1 { font-size: clamp(36px, 5vw, 58px); }

.hero-lead,
.page-hero p {
  max-width: 760px;
  color: rgba(255,255,255,.78);
  font-size: 19px;
}

.hero-actions,
.formula-actions,
.progress-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 28px;
}

.hero-note {
  margin-top: 18px;
  color: rgba(255,255,255,.64);
  font-size: 13px;
}

.button {
  min-height: 46px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 11px 18px;
  border: 1px solid transparent;
  border-radius: 12px;
  cursor: pointer;
  font-weight: 750;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}

.button:hover { transform: translateY(-1px); }
.button.primary {
  color: #15212d;
  background: var(--accent);
  box-shadow: 0 10px 30px rgba(230,168,51,.18);
}
.button.secondary {
  color: var(--navy);
  border-color: #b9c7d2;
  background: white;
}
.hero .button.secondary,
.page-hero .button.secondary {
  color: white;
  border-color: rgba(255,255,255,.32);
  background: rgba(255,255,255,.08);
}
.button.small { min-height: 40px; padding: 8px 14px; }
.button.wide { width: 100%; }
.button.disabled {
  color: #89939d;
  background: #e8edf0;
  cursor: default;
}

.hero-panel {
  min-height: 390px;
  display: grid;
  place-items: center;
}

.formula-orbit {
  position: relative;
  width: 330px;
  aspect-ratio: 1;
  display: grid;
  place-items: center;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 50%;
  background: radial-gradient(circle, rgba(255,255,255,.10), transparent 62%);
}

.formula-main {
  width: 160px;
  height: 160px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--navy);
  background: var(--accent);
  font-family: Georgia, serif;
  font-size: 38px;
  font-weight: 700;
  box-shadow: 0 24px 70px rgba(0,0,0,.22);
}

.orbit {
  position: absolute;
  padding: 8px 12px;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 999px;
  color: rgba(255,255,255,.92);
  background: rgba(15,35,53,.62);
  font-family: Georgia, serif;
}
.orbit-one { top: 23px; left: 10px; }
.orbit-two { right: -12px; top: 126px; }
.orbit-three { left: 22px; bottom: 26px; }

.stats-section { margin-top: -28px; position: relative; z-index: 2; }
.stats-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: var(--shadow);
}
.stat-card {
  padding: 24px;
  text-align: center;
}
.stat-card + .stat-card { border-left: 1px solid var(--line); }
.stat-card strong {
  display: block;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 34px;
}
.stat-card span { color: var(--muted); font-size: 13px; }

.section { padding: 72px 0; }
.section-soft { background: var(--soft); }

.section-heading {
  margin-bottom: 28px;
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 24px;
}

.section-heading h2,
.chapter-heading h2,
.search-banner h2,
.prose h2 {
  margin: 6px 0 0;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: clamp(28px, 4vw, 42px);
  line-height: 1.15;
}

.text-link {
  color: var(--navy-2);
  font-weight: 750;
}

.grade-grid,
.topic-grid,
.formula-grid {
  display: grid;
  gap: 20px;
}

.grade-grid { grid-template-columns: repeat(3, 1fr); }

.grade-card {
  min-height: 170px;
  position: relative;
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 28px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: 0 10px 30px rgba(24,50,75,.06);
}
.grade-card::after {
  content: "";
  position: absolute;
  width: 140px;
  height: 140px;
  right: -55px;
  bottom: -65px;
  border-radius: 50%;
  background: var(--accent-soft);
}
.grade-number {
  color: var(--accent);
  font-family: Georgia, serif;
  font-size: 58px;
  font-weight: 700;
}
.grade-card h3 { margin: 0; color: var(--navy); font-size: 22px; }
.grade-card p { margin: 4px 0 0; color: var(--muted); }
.arrow { margin-left: auto; color: var(--navy); font-size: 24px; }

.formula-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}

.formula-tile {
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: white;
  box-shadow: 0 12px 30px rgba(24,50,75,.06);
}

.formula-thumb {
  display: block;
  padding: 12px;
  background:
    linear-gradient(135deg, #f5f8fa, #e9eff3);
}

.formula-thumb img {
  width: 100%;
  aspect-ratio: 3 / 1;
  object-fit: contain;
  border-radius: 10px;
  background: white;
}

.formula-tile-body { padding: 18px; }
.formula-tile h3 {
  min-height: 52px;
  margin: 9px 0 7px;
  color: var(--navy);
  font-size: 18px;
  line-height: 1.35;
}

.formula-meta {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  color: var(--muted);
  font-size: 12px;
  font-weight: 750;
}

.badge {
  padding: 3px 8px;
  border-radius: 999px;
  color: #77520b;
  background: var(--accent-soft);
}

.equation-preview {
  min-height: 46px;
  margin: 0;
  color: var(--muted);
  font-family: Georgia, serif;
}

.tile-actions {
  margin-top: 14px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.icon-button {
  width: 38px;
  height: 38px;
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--navy);
  background: white;
  cursor: pointer;
  font-size: 21px;
}
.icon-button.is-favorite {
  color: #91620a;
  border-color: #efc765;
  background: var(--accent-soft);
}

.search-banner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  align-items: center;
  gap: 40px;
  padding: 38px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: var(--shadow);
}

.search-form {
  display: flex;
  gap: 10px;
  margin-top: 24px;
}
.search-form-large { margin-top: 0; }
.search-form input {
  width: 100%;
  min-height: 48px;
  padding: 10px 14px;
  border: 1px solid #b8c5cf;
  border-radius: 12px;
  background: white;
  outline: none;
}
.search-form input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(230,168,51,.18);
}

.breadcrumbs {
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  color: rgba(255,255,255,.64);
  font-size: 13px;
}
.formula-page .breadcrumbs { color: var(--muted); padding-top: 30px; }
.breadcrumbs a:hover { color: var(--accent); }

.catalog-grade-block + .catalog-grade-block { margin-top: 68px; }
.topic-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }

.topic-card {
  min-height: 118px;
  display: flex;
  align-items: center;
  gap: 16px;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 15px;
  background: white;
  box-shadow: 0 8px 24px rgba(24,50,75,.05);
}
.topic-index {
  width: 42px;
  height: 42px;
  flex: 0 0 42px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--navy);
  background: var(--accent-soft);
  font-weight: 850;
}
.topic-card h3 { margin: 0; color: var(--navy); font-size: 18px; }
.topic-card p { margin: 4px 0 0; color: var(--muted); }

.topic-stack { display: grid; gap: 24px; }
.chapter-panel {
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
}
.chapter-heading {
  display: flex;
  align-items: start;
  justify-content: space-between;
  gap: 22px;
}
.chapter-heading p { color: var(--muted); }

.mini-formula-list {
  margin-top: 22px;
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 10px;
}
.mini-formula-list a {
  display: flex;
  justify-content: space-between;
  gap: 12px;
  padding: 12px 14px;
  border-radius: 10px;
  color: var(--navy);
  background: var(--soft);
  font-size: 14px;
}
.mini-formula-list .more-link {
  color: #76500b;
  background: var(--accent-soft);
}

.formula-page { padding-bottom: 72px; }
.formula-layout {
  display: grid;
  grid-template-columns: 1.15fr .85fr;
  align-items: start;
  gap: 28px;
}
.formula-image-panel,
.formula-content-card {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: var(--shadow);
}
.formula-image-panel {
  position: sticky;
  top: 96px;
  padding: 20px;
}
.formula-image-panel img {
  width: 100%;
  border-radius: 12px;
}
.formula-content-card { padding: 30px; }
.formula-content-card h1 {
  margin: 10px 0 14px;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: clamp(30px, 4vw, 44px);
  line-height: 1.1;
}
.formula-equation {
  padding: 18px;
  border-left: 4px solid var(--accent);
  border-radius: 0 12px 12px 0;
  color: var(--navy);
  background: var(--accent-soft);
  font-family: Georgia, serif;
  font-size: 22px;
}
.detail-section { margin-top: 26px; }
.detail-section h2 { color: var(--navy); font-size: 19px; }
.quantity-list { margin: 0; padding-left: 20px; }
.quantity-list li + li { margin-top: 9px; }
.note-box {
  margin-top: 24px;
  padding: 18px;
  border: 1px solid #e8ca82;
  border-radius: 12px;
  background: #fff8e7;
}
.note-box strong { color: #76500b; }
.note-box p { margin: 5px 0 0; }

.formula-navigation {
  margin-top: 24px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}
.formula-navigation a {
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: white;
}
.formula-navigation a.next { text-align: right; }
.formula-navigation span { display: block; color: var(--muted); font-size: 12px; }
.formula-navigation strong { display: block; margin-top: 4px; color: var(--navy); }

.empty-state {
  max-width: 620px;
  margin: 30px auto;
  padding: 48px 24px;
  text-align: center;
}
.empty-icon {
  width: 72px;
  height: 72px;
  margin: 0 auto 18px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--navy);
  background: var(--accent-soft);
  font-size: 25px;
  font-weight: 850;
}
.empty-state h1,
.empty-state h2 { color: var(--navy); }
.empty-state p { color: var(--muted); }

.quiz-shell {
  max-width: 850px;
}
.quiz-setup,
.quiz-question-card,
.quiz-result {
  padding: 30px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: var(--shadow);
}
.setup-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.setup-grid label span {
  display: block;
  margin-bottom: 6px;
  color: var(--navy);
  font-weight: 750;
}
.setup-grid select {
  width: 100%;
  min-height: 48px;
  padding: 8px 12px;
  border: 1px solid #b8c5cf;
  border-radius: 10px;
  background: white;
}
.quiz-scope-note {
  min-height: 24px;
  margin: 18px 0;
  color: var(--muted);
}
.quiz-loading {
  padding: 40px;
  text-align: center;
  color: var(--muted);
}
.quiz-progress-bar {
  height: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: #e8edf0;
}
.quiz-progress-bar span {
  display: block;
  height: 100%;
  border-radius: inherit;
  background: var(--accent);
}
.quiz-topline {
  margin: 14px 0 18px;
  display: flex;
  justify-content: space-between;
  gap: 20px;
  color: var(--muted);
  font-size: 13px;
}
.quiz-question-card h2 {
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 29px;
  line-height: 1.25;
}
.quiz-options {
  display: grid;
  gap: 12px;
  margin-top: 22px;
}
.quiz-option {
  width: 100%;
  padding: 15px 16px;
  text-align: left;
  border: 1px solid #bdc8d1;
  border-radius: 12px;
  color: var(--ink);
  background: white;
  cursor: pointer;
}
.quiz-option:hover { border-color: var(--accent); background: #fffaf0; }
.quiz-option.correct {
  color: #145f43;
  border-color: #68b393;
  background: #e8f6ef;
}
.quiz-option.wrong {
  color: #8b3030;
  border-color: #d79393;
  background: #fbecec;
}
.quiz-option:disabled { cursor: default; }
.quiz-feedback {
  margin-top: 20px;
  padding: 16px;
  border-radius: 12px;
  background: var(--soft);
}
.quiz-feedback strong { display: block; color: var(--navy); }
.quiz-feedback p { margin: 5px 0 0; }
.quiz-next { margin-top: 18px; }
.quiz-result { text-align: center; }
.quiz-score {
  margin: 15px 0;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 64px;
  font-weight: 700;
}
.quiz-result-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
}

.progress-summary {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.progress-stat {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 14px;
  background: white;
}
.progress-stat strong {
  display: block;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 32px;
}
.progress-stat span { color: var(--muted); font-size: 13px; }
.progress-columns {
  margin-top: 22px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 22px;
}
.progress-panel {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: 16px;
  background: white;
}
.progress-panel h2 { color: var(--navy); }
.progress-row {
  padding: 13px 0;
  display: flex;
  justify-content: space-between;
  gap: 16px;
  border-bottom: 1px solid var(--line);
}
.progress-row:last-child { border-bottom: 0; }
.progress-meter {
  height: 8px;
  margin-top: 8px;
  overflow: hidden;
  border-radius: 999px;
  background: #e8edf0;
}
.progress-meter span {
  display: block;
  height: 100%;
  background: var(--accent);
}
.weak-list { display: grid; gap: 10px; }
.weak-item {
  padding: 12px;
  border-radius: 10px;
  background: var(--soft);
}
.weak-item strong { color: var(--navy); }
.weak-item span { display: block; color: var(--muted); font-size: 12px; }

.prose { font-size: 18px; }
.prose h2 { margin-top: 42px; }
.prose li + li { margin-top: 8px; }

.site-footer {
  padding: 42px 0;
  color: rgba(255,255,255,.72);
  background: #11283d;
}
.footer-grid {
  display: grid;
  grid-template-columns: 1.4fr .8fr .8fr;
  gap: 32px;
}
.site-footer strong { color: white; }
.site-footer p { max-width: 420px; }
.site-footer a { display: block; margin-bottom: 7px; }
.footer-version { text-align: right; }

@media (max-width: 960px) {
  .hero-grid,
  .formula-layout,
  .search-banner {
    grid-template-columns: 1fr;
  }
  .hero-panel { min-height: 330px; }
  .formula-image-panel { position: static; }
  .formula-grid { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .grade-grid { grid-template-columns: 1fr; }
  .progress-summary { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 760px) {
  .menu-toggle { display: block; }
  .main-nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 64px;
    padding: 16px;
    align-items: stretch;
    flex-direction: column;
    gap: 4px;
    border-radius: 14px;
    color: var(--ink);
    background: white;
    box-shadow: var(--shadow);
  }
  .main-nav.is-open { display: flex; }
  .main-nav a { padding: 10px; color: var(--navy); }
  .hero { padding: 58px 0; }
  .hero h1 { font-size: 43px; }
  .hero-panel { display: none; }
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
  .stat-card + .stat-card { border-left: 0; }
  .stat-card:nth-child(even) { border-left: 1px solid var(--line); }
  .stat-card:nth-child(n+3) { border-top: 1px solid var(--line); }
  .formula-grid,
  .topic-grid,
  .mini-formula-list,
  .setup-grid,
  .progress-columns,
  .footer-grid {
    grid-template-columns: 1fr;
  }
  .section { padding: 52px 0; }
  .section-heading,
  .chapter-heading {
    align-items: start;
    flex-direction: column;
  }
  .search-form { flex-direction: column; }
  .formula-navigation { grid-template-columns: 1fr; }
  .formula-navigation a.next { text-align: left; }
  .formula-content-card,
  .quiz-setup,
  .quiz-question-card,
  .quiz-result {
    padding: 22px;
  }
  .footer-version { text-align: left; }
}

@media (max-width: 480px) {
  .container { width: min(100% - 20px, 1180px); }
  .hero h1 { font-size: 38px; }
  .page-hero h1 { font-size: 36px; }
  .formula-grid { grid-template-columns: 1fr; }
  .progress-summary { grid-template-columns: 1fr 1fr; gap: 9px; }
  .progress-stat { padding: 16px; }
  .progress-stat strong { font-size: 27px; }
  .formula-actions { flex-direction: column; }
  .formula-actions .button { width: 100%; }
}

/* ==================================================================
   v0.2 «Открытая физика»
   Русскоязычный бренд, космико-физическая айдентика и устойчивые
   обозначения векторных/усреднённых величин.
   ================================================================== */
:root {
  --navy: #112b46;
  --navy-2: #1a4268;
  --navy-3: #245b89;
  --accent: #efb02f;
  --accent-2: #f7cc69;
  --accent-soft: #fff3d3;
  --cyan: #79d9ff;
  --violet: #9d87ff;
  --paper: #fbfaf6;
  --soft: #eef4f7;
  --shadow: 0 22px 58px rgba(14, 42, 69, .11);
  --radius: 20px;
}

body {
  background:
    radial-gradient(circle at 8% 18%, rgba(121,217,255,.08), transparent 24%),
    radial-gradient(circle at 92% 72%, rgba(157,135,255,.07), transparent 28%),
    var(--paper);
}

.ambient-field {
  position: fixed;
  inset: 0;
  z-index: -1;
  pointer-events: none;
  opacity: .32;
  background-image:
    radial-gradient(circle at 10% 20%, rgba(36,91,137,.16) 0 1px, transparent 1.6px),
    radial-gradient(circle at 75% 28%, rgba(36,91,137,.12) 0 1px, transparent 1.6px),
    radial-gradient(circle at 45% 82%, rgba(36,91,137,.10) 0 1px, transparent 1.6px);
  background-size: 90px 90px, 130px 130px, 170px 170px;
}

.site-header {
  border-bottom-color: rgba(121,217,255,.10);
  background:
    linear-gradient(90deg, rgba(121,217,255,.04), transparent 28%, rgba(157,135,255,.04)),
    rgba(17, 43, 70, .97);
  backdrop-filter: blur(14px);
}

.header-inner { min-height: 76px; }

.brand-mark {
  width: 46px;
  height: 46px;
  flex: 0 0 46px;
}

.brand strong { font-size: 17px; }
.brand small { color: rgba(255,255,255,.66); font-size: 11px; }
.main-nav { gap: 19px; font-size: 13px; }
.main-nav a:hover { color: var(--accent-2); }

.menu-toggle {
  width: 42px;
  height: 42px;
  padding: 10px;
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 11px;
  background: rgba(255,255,255,.05);
}
.menu-toggle span { display: block; height: 2px; margin: 4px 0; background: white; }

.hero,
.page-hero {
  position: relative;
  overflow: hidden;
  background:
    radial-gradient(circle at 82% 18%, rgba(121,217,255,.13), transparent 23%),
    radial-gradient(circle at 68% 72%, rgba(157,135,255,.13), transparent 28%),
    linear-gradient(142deg, #102b46 0%, #173f63 56%, #102b46 100%);
}

.cosmic-surface::before {
  content: "";
  position: absolute;
  inset: 0;
  pointer-events: none;
  opacity: .36;
  background-image:
    radial-gradient(circle at 18% 22%, white 0 1px, transparent 1.5px),
    radial-gradient(circle at 77% 17%, rgba(255,255,255,.75) 0 1px, transparent 1.6px),
    radial-gradient(circle at 36% 78%, rgba(121,217,255,.8) 0 1px, transparent 1.6px),
    radial-gradient(circle at 88% 73%, rgba(247,204,105,.8) 0 1px, transparent 1.6px);
  background-size: 110px 110px, 160px 160px, 210px 210px, 260px 260px;
}

.hero { padding: 86px 0 78px; }
.hero-grid { grid-template-columns: 1.08fr .92fr; gap: 68px; position: relative; z-index: 1; }
.hero-copy { position: relative; z-index: 2; }

.release-pill {
  width: max-content;
  max-width: 100%;
  margin-bottom: 22px;
  display: inline-flex;
  align-items: center;
  gap: 9px;
  padding: 7px 12px;
  border: 1px solid rgba(121,217,255,.24);
  border-radius: 999px;
  color: rgba(255,255,255,.80);
  background: rgba(7,27,45,.34);
  font-size: 12px;
  font-weight: 650;
}

.pulse-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 5px rgba(121,217,255,.10);
}

.hero h1 { font-size: clamp(44px, 6.1vw, 74px); line-height: 1.06; text-wrap: balance; }
.hero-lead { font-size: 18px; }
.button.primary { background: linear-gradient(135deg, var(--accent), var(--accent-2)); }
.button.ghost { color: white; border-color: rgba(255,255,255,.32); background: rgba(255,255,255,.07); }

.hero-facts {
  margin-top: 20px;
  display: flex;
  flex-wrap: wrap;
  gap: 10px 18px;
  color: rgba(255,255,255,.64);
  font-size: 12px;
}
.hero-facts span::before { content: "·"; margin-right: 7px; color: var(--cyan); }

.quantum-scene {
  position: relative;
  min-height: 430px;
  display: grid;
  place-items: center;
  isolation: isolate;
}
.quantum-grid {
  position: absolute;
  width: 390px;
  height: 390px;
  border: 1px solid rgba(121,217,255,.18);
  border-radius: 50%;
  background:
    linear-gradient(rgba(121,217,255,.06) 1px, transparent 1px),
    linear-gradient(90deg, rgba(121,217,255,.06) 1px, transparent 1px);
  background-size: 34px 34px;
  mask-image: radial-gradient(circle, #000 25%, transparent 72%);
}
.atom-core {
  position: relative;
  z-index: 5;
  width: 142px;
  height: 142px;
  display: grid;
  place-items: center;
  border-radius: 50%;
  color: var(--navy);
  background:
    radial-gradient(circle at 32% 28%, #ffe7a6, transparent 24%),
    linear-gradient(145deg, var(--accent-2), var(--accent));
  box-shadow: 0 0 0 18px rgba(239,176,47,.06), 0 28px 70px rgba(0,0,0,.24);
}
.atom-core span { margin-top: 7px; font-family: Georgia, serif; font-size: 64px; font-weight: 700; line-height: .8; }
.atom-core small { margin-top: -34px; font-size: 9px; font-weight: 800; letter-spacing: .14em; text-transform: uppercase; }
.electron-orbit { position: absolute; width: 340px; height: 138px; border: 1px solid rgba(121,217,255,.30); border-radius: 50%; }
.electron-orbit i { position: absolute; width: 10px; height: 10px; top: 50%; right: -5px; border-radius: 50%; background: var(--cyan); box-shadow: 0 0 18px var(--cyan); }
.orbit-a { transform: rotate(18deg); }
.orbit-b { transform: rotate(78deg); }
.orbit-b i { background: var(--violet); box-shadow: 0 0 18px var(--violet); }
.orbit-c { transform: rotate(138deg); }
.orbit-c i { background: var(--accent); box-shadow: 0 0 18px var(--accent); }
.formula-node { position: absolute; z-index: 6; padding: 8px 12px; border: 1px solid rgba(255,255,255,.16); border-radius: 999px; color: rgba(255,255,255,.90); background: rgba(8,30,50,.62); backdrop-filter: blur(8px); font-family: Georgia, serif; font-size: 14px; }
.node-a { top: 72px; left: 18px; }
.node-b { right: 2px; top: 176px; }
.node-c { left: 40px; bottom: 62px; }
.wave-line { position: absolute; width: 420px; bottom: 4px; opacity: .36; fill: none; stroke: var(--cyan); stroke-width: 2; }

.stats-section { margin-top: -31px; z-index: 4; }
.stats-grid { background: rgba(255,255,255,.96); }
.stat-card { position: relative; }
.stat-symbol { position: absolute; left: 18px; top: 14px; color: rgba(36,91,137,.18); font-family: Georgia, serif; font-size: 20px; font-weight: 700; }
.stat-card > span:last-child { font-size: 12px; }

.section-heading h2,
.chapter-heading h2,
.search-banner h2,
.prose h2,
.training-copy h2,
.trust-grid h2 { text-wrap: balance; }
.section-lead, .search-banner p, .training-copy p { max-width: 690px; margin: 10px 0 0; color: var(--muted); }

.grade-card {
  min-height: 174px;
  background: radial-gradient(circle at 90% 20%, rgba(121,217,255,.12), transparent 28%), white;
}
.grade-card::after { border: 1px solid rgba(36,91,137,.12); background: transparent; }
.grade-orbit { position: absolute; width: 86px; height: 34px; right: 18px; top: 20px; border: 1px solid rgba(157,135,255,.22); border-radius: 50%; transform: rotate(-18deg); }
.grade-orbit::after { content: ""; position: absolute; width: 7px; height: 7px; right: -3px; top: 12px; border-radius: 50%; background: var(--violet); }

.section-constellation { position: relative; overflow: hidden; background: radial-gradient(circle at 12% 22%, rgba(157,135,255,.10), transparent 24%), radial-gradient(circle at 85% 78%, rgba(121,217,255,.09), transparent 28%), white; }
.section-constellation::before { content: ""; position: absolute; inset: 0; pointer-events: none; opacity: .22; background-image: radial-gradient(circle, var(--navy-3) 0 1px, transparent 1.4px); background-size: 88px 88px; }
.method-grid { grid-template-columns: repeat(3, 1fr); position: relative; }
.method-card { position: relative; min-height: 270px; padding: 28px; border: 1px solid var(--line); border-radius: var(--radius); background: rgba(255,255,255,.92); box-shadow: 0 14px 36px rgba(24,50,75,.06); }
.method-index { position: absolute; right: 20px; top: 14px; color: rgba(17,43,70,.10); font-family: Georgia, serif; font-size: 44px; font-weight: 700; }
.method-icon { width: 54px; height: 54px; display: grid; place-items: center; border: 1px solid rgba(121,217,255,.26); border-radius: 50%; color: var(--navy); background: linear-gradient(145deg, rgba(121,217,255,.16), rgba(157,135,255,.10)); font-family: Georgia, serif; font-size: 23px; font-weight: 700; }
.method-card h3 { margin: 22px 0 8px; color: var(--navy); font-size: 21px; }
.method-card p { margin: 0; color: var(--muted); }

.formula-tile { border-radius: 17px; transition: transform .18s ease, box-shadow .18s ease; }
.formula-tile:hover { transform: translateY(-3px); box-shadow: 0 20px 42px rgba(24,50,75,.11); }
.formula-thumb { position: relative; overflow: hidden; }
.thumb-quantum { position: absolute; width: 120px; height: 48px; right: -14px; top: -10px; border: 1px solid rgba(121,217,255,.24); border-radius: 50%; transform: rotate(16deg); }
.formula-thumb img { position: relative; z-index: 1; }
.formula-meta { gap: 7px; font-size: 11px; }
.formula-meta span:not(.badge) + span:not(.badge)::before { content: "·"; margin-right: 7px; color: #a4b1bc; }

.vector-symbol,
.average-symbol { position: relative; display: inline-block; min-width: .62em; text-align: center; }
.vector-symbol::before { content: "→"; position: absolute; left: 50%; top: -.82em; transform: translateX(-50%) scaleX(.76); font-family: sans-serif; font-size: .58em; font-weight: 700; line-height: 1; }
.average-symbol::before { content: ""; position: absolute; left: 8%; right: 8%; top: -.18em; height: 1px; background: currentColor; }

.training-lab { display: grid; grid-template-columns: .8fr 1.2fr; gap: 42px; align-items: start; padding: 38px; border: 1px solid var(--line); border-radius: var(--radius); background: radial-gradient(circle at 0% 0%, rgba(121,217,255,.11), transparent 26%), white; box-shadow: var(--shadow); }
.training-options { display: grid; gap: 12px; }
.training-option { display: grid; grid-template-columns: auto 1fr auto; align-items: center; gap: 14px; padding: 15px; border: 1px solid var(--line); border-radius: 14px; background: var(--soft); }
.training-option:hover { border-color: rgba(36,91,137,.28); background: #eaf2f7; }
.training-orb { width: 42px; height: 42px; display: grid; place-items: center; border-radius: 50%; color: var(--navy); background: linear-gradient(145deg, var(--accent-soft), rgba(121,217,255,.18)); font-family: Georgia, serif; font-weight: 700; }
.training-option strong, .training-option small { display: block; }
.training-option strong { color: var(--navy); }
.training-option small { margin-top: 2px; color: var(--muted); }

.trust-section { border-top: 1px solid var(--line); background: radial-gradient(circle at 85% 20%, rgba(157,135,255,.08), transparent 26%); }
.trust-grid { display: grid; grid-template-columns: .9fr 1.1fr; gap: 50px; align-items: start; }
.trust-list { margin: 0; padding: 0; list-style: none; }
.trust-list li { position: relative; padding: 15px 0 15px 34px; border-bottom: 1px solid var(--line); }
.trust-list li::before { content: "✓"; position: absolute; left: 0; top: 14px; width: 22px; height: 22px; display: grid; place-items: center; border-radius: 50%; color: var(--success); background: #e8f5ef; font-size: 12px; font-weight: 800; }

.dark-breadcrumbs { color: var(--muted); padding-top: 30px; }
.formula-image-panel { overflow: hidden; }
.panel-orbit { position: absolute; width: 190px; height: 72px; right: -46px; top: -18px; border: 1px solid rgba(121,217,255,.22); border-radius: 50%; transform: rotate(18deg); }
.formula-image-panel img { position: relative; z-index: 1; }
.formula-equation { background: linear-gradient(90deg, var(--accent-soft), rgba(121,217,255,.08)); line-height: 1.55; }
.note-box { background: radial-gradient(circle at 100% 0%, rgba(121,217,255,.13), transparent 28%), #fff8e7; }
.formula-utility-links { margin-top: 18px; display: flex; flex-wrap: wrap; gap: 12px 20px; font-size: 13px; }
.formula-utility-links a, .formula-utility-links button { padding: 0; border: 0; color: var(--navy-2); background: transparent; cursor: pointer; font-weight: 720; }

.setup-grid-four { grid-template-columns: 1.2fr .8fr 1.2fr .8fr; }
.quiz-progress-bar span, .progress-meter span { background: linear-gradient(90deg, var(--accent), var(--cyan)); }
.personal-quiz-link { position: relative; z-index: 2; margin-top: 18px; }

.site-footer { background: radial-gradient(circle at 80% 20%, rgba(121,217,255,.08), transparent 25%), #0e263c; }
.footer-grid { grid-template-columns: 1.35fr .65fr .7fr .8fr; gap: 34px; }
.footer-brand img { width: 42px; height: 42px; object-fit: cover; object-position: center 28%; border-radius: 50%; border: 2px solid rgba(239,176,47,.72); }
.footer-brand strong { color: white; }
.footer-brand small { color: rgba(255,255,255,.56); font-size: 11px; }
.footer-links strong, .footer-links a { display: block; }
.footer-links strong { margin-bottom: 12px; color: white; }
.footer-links a { margin-bottom: 8px; }
.footer-links a:hover { color: var(--accent-2); }
.footer-release { padding-left: 18px; border-left: 1px solid rgba(255,255,255,.12); }
.footer-release span, .footer-release strong, .footer-release small { display: block; }
.footer-release span { color: var(--accent-2); font-size: 12px; font-weight: 800; }
.footer-release strong { margin: 5px 0 10px; color: white; }
.footer-release small { line-height: 1.5; }

@media (prefers-reduced-motion: no-preference) {
  .orbit-a { animation: drift-a 12s ease-in-out infinite alternate; }
  .orbit-b { animation: drift-b 15s ease-in-out infinite alternate; }
  .orbit-c { animation: drift-c 18s ease-in-out infinite alternate; }
  @keyframes drift-a { from { transform: rotate(15deg); } to { transform: rotate(25deg); } }
  @keyframes drift-b { from { transform: rotate(74deg); } to { transform: rotate(83deg); } }
  @keyframes drift-c { from { transform: rotate(134deg); } to { transform: rotate(143deg); } }
}

@media (max-width: 1040px) {
  .main-nav { gap: 14px; font-size: 12px; }
  .hero-grid, .training-lab, .trust-grid { grid-template-columns: 1fr; }
  .method-grid { grid-template-columns: 1fr; }
  .setup-grid-four { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 820px) {
  .menu-toggle { display: block; }
  .main-nav { top: 67px; }
  .hero { padding: 58px 0 62px; }
  .hero h1 { font-size: 45px; }
  .hero-profile-scene { display: grid; min-height: 380px; margin-top: 8px; }
  .hero-portrait-shell { width: min(320px, 82vw); }
  .hero-profile-note { position: static; margin-top: 18px; }
  .formula-node { font-size: 13px; }
  .setup-grid-four, .footer-grid { grid-template-columns: 1fr; }
  .training-lab { padding: 22px; }
  .footer-release { padding-left: 0; padding-top: 20px; border-left: 0; border-top: 1px solid rgba(255,255,255,.12); }
}

@media (max-width: 500px) {
  .brand strong { font-size: 15px; }
  .brand small { font-size: 10px; }
  .brand-mark { width: 40px; height: 40px; flex-basis: 40px; }
  .hero h1 { font-size: 39px; }
  .hero-facts { display: grid; gap: 7px; }
}

/* ==================================================================
   v0.3 — дроби, связь с автором и отзывы
   ================================================================== */
.math-frac {
  min-width: 1.18em;
  display: inline-flex;
  flex-direction: column;
  align-items: stretch;
  justify-content: center;
  margin: 0 .10em;
  vertical-align: -.48em;
  text-align: center;
  line-height: 1.03;
  white-space: nowrap;
}
.math-frac-num,
.math-frac-den {
  display: block;
  padding-inline: .16em;
}
.math-frac-num {
  padding-bottom: .08em;
  border-bottom: 1.35px solid currentColor;
}
.math-frac-den { padding-top: .08em; }
.math-op { white-space: pre; }
.inline-frac { font-size: .92em; vertical-align: -.42em; }
.equation-preview { line-height: 1.72; }
.formula-equation { min-height: 68px; display: flex; align-items: center; flex-wrap: wrap; gap: .05em; }
.formula-equation .math-frac { vertical-align: -.54em; }
.quiz-option { min-height: 58px; line-height: 1.72; }
.quiz-feedback { line-height: 1.72; }

.nav-contact-button {
  min-height: 34px;
  padding: 7px 13px;
  border: 1px solid rgba(247, 204, 105, .52);
  border-radius: 10px;
  color: #172434;
  background: var(--accent);
  cursor: pointer;
  font-weight: 800;
  transition: transform .18s ease, box-shadow .18s ease, background .18s ease;
}
.nav-contact-button:hover {
  transform: translateY(-1px);
  background: var(--accent-2);
  box-shadow: 0 8px 22px rgba(239,176,47,.22);
}

body.modal-open { overflow: hidden; }
.contact-modal[hidden] { display: none; }
.contact-modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: grid;
  place-items: center;
  padding: 20px;
}
.contact-modal-backdrop {
  position: absolute;
  inset: 0;
  border: 0;
  background: rgba(5, 22, 37, .72);
  backdrop-filter: blur(7px);
  cursor: default;
}
.contact-modal-card {
  width: min(500px, 100%);
  position: relative;
  z-index: 1;
  padding: 34px;
  border: 1px solid rgba(121,217,255,.22);
  border-radius: 22px;
  background:
    radial-gradient(circle at 100% 0%, rgba(121,217,255,.13), transparent 30%),
    white;
  box-shadow: 0 30px 90px rgba(2,18,31,.32);
}
.contact-modal-card h2 {
  margin: 8px 0 10px;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 34px;
}
.contact-modal-card p { margin: 0; color: var(--muted); }
.contact-modal-close {
  width: 40px;
  height: 40px;
  position: absolute;
  right: 14px;
  top: 14px;
  border: 1px solid var(--line);
  border-radius: 50%;
  color: var(--navy);
  background: white;
  cursor: pointer;
  font-size: 25px;
  line-height: 1;
}
.contact-modal-actions,
.contact-actions,
.about-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
}
.contact-modal-actions { margin-top: 24px; }
.contact-modal-actions .button { flex: 1 1 170px; }
.contact-modal-about {
  display: inline-block;
  margin-top: 20px;
  color: var(--navy-2);
  font-weight: 750;
}

.about-actions {
  margin-top: 32px;
  align-items: center;
}
.author-section { position: relative; overflow: hidden; }
.author-section::before {
  content: "";
  position: absolute;
  width: 360px;
  height: 360px;
  right: -170px;
  top: -130px;
  border: 1px solid rgba(157,135,255,.18);
  border-radius: 50%;
}
.author-layout {
  position: relative;
  display: grid;
  grid-template-columns: .82fr 1.18fr;
  gap: 34px;
  align-items: start;
}
.author-card,
.contact-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: 0 16px 42px rgba(24,50,75,.07);
}
.author-card {
  position: sticky;
  top: 96px;
  padding: 30px;
  overflow: hidden;
}
.author-card::after {
  content: "";
  position: absolute;
  width: 130px;
  height: 54px;
  right: -22px;
  top: 24px;
  border: 1px solid rgba(121,217,255,.28);
  border-radius: 50%;
  transform: rotate(18deg);
}
.author-monogram {
  width: 76px;
  height: 76px;
  display: grid;
  place-items: center;
  margin-bottom: 24px;
  border-radius: 50%;
  color: var(--navy);
  background: linear-gradient(145deg, var(--accent), var(--accent-2));
  font-family: Georgia, serif;
  font-size: 42px;
  font-weight: 700;
  box-shadow: 0 14px 34px rgba(239,176,47,.22);
}
.author-card h2 {
  margin: 9px 0 13px;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 32px;
  line-height: 1.12;
}
.author-card > p { color: var(--muted); }
.author-facts {
  margin-top: 24px;
  display: grid;
  gap: 12px;
}
.author-facts div {
  padding: 14px 0;
  border-top: 1px solid var(--line);
}
.author-facts strong,
.author-facts span { display: block; }
.author-facts strong { color: var(--navy); font-size: 19px; }
.author-facts span { color: var(--muted); font-size: 13px; }
.author-copy { font-size: 18px; }
.author-copy h2 { margin-top: 0; }
.contact-panel {
  margin-top: 30px;
  padding: 24px;
  background:
    radial-gradient(circle at 100% 0%, rgba(121,217,255,.14), transparent 30%),
    white;
}
.contact-panel > strong { color: var(--navy); font-size: 20px; }
.contact-panel > p { margin: 7px 0 20px; color: var(--muted); }

.reviews-section {
  background:
    radial-gradient(circle at 8% 18%, rgba(121,217,255,.08), transparent 23%),
    radial-gradient(circle at 92% 80%, rgba(157,135,255,.07), transparent 27%),
    white;
}
.reviews-heading { align-items: center; }
.reviews-heading > div { max-width: 760px; }
.reviews-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}
.review-card {
  min-height: 210px;
  display: grid;
  place-items: center;
  padding: 12px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: white;
  box-shadow: 0 12px 34px rgba(24,50,75,.07);
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.review-card:hover {
  transform: translateY(-3px);
  border-color: rgba(36,91,137,.24);
  box-shadow: 0 20px 48px rgba(24,50,75,.12);
}
.review-card img {
  width: 100%;
  height: auto;
  border-radius: 10px;
}

@media (max-width: 1180px) {
  .main-nav { gap: 11px; }
  .main-nav a { font-size: 12px; }
  .nav-contact-button { padding-inline: 10px; font-size: 12px; }
}

@media (max-width: 820px) {
  .main-nav .nav-contact-button {
    width: 100%;
    margin-top: 6px;
    padding: 11px;
  }
  .author-layout { grid-template-columns: 1fr; }
  .author-card { position: static; }
  .reviews-grid { grid-template-columns: 1fr; }
  .reviews-heading { align-items: flex-start; }
}

@media (max-width: 500px) {
  .contact-modal { padding: 10px; }
  .contact-modal-card { padding: 28px 20px 22px; }
  .contact-modal-card h2 { font-size: 29px; }
  .contact-modal-actions,
  .contact-actions,
  .about-actions { flex-direction: column; align-items: stretch; }
  .contact-modal-actions .button { flex-basis: auto; }
  .about-actions .button,
  .contact-actions .button { width: 100%; }
  .author-card { padding: 24px; }
  .author-card h2 { font-size: 28px; }
  .review-card { padding: 7px; min-height: 0; }
  .formula-equation { font-size: 20px; }
  .quiz-option { padding: 14px 13px; }
}

/* ==================================================================
   v0.4 — онлайн, добровольные аккаунты и панель администратора
   ================================================================== */
.header-activity {
  position: fixed;
  right: 18px;
  bottom: 18px;
  z-index: 24;
  pointer-events: none;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 9px 13px;
  border: 1px solid rgba(121,217,255,.28);
  border-radius: 999px;
  color: white;
  background: rgba(17,43,70,.94);
  box-shadow: 0 12px 34px rgba(5,22,37,.24);
  backdrop-filter: blur(10px);
  font-size: 12px;
  font-weight: 700;
}
.online-dot {
  width: 9px;
  height: 9px;
  flex: 0 0 9px;
  border-radius: 50%;
  background: #68d69c;
  box-shadow: 0 0 0 4px rgba(104,214,156,.14), 0 0 14px rgba(104,214,156,.54);
}
.header-activity strong { color: var(--accent-2); }

.nav-account-button,
.nav-contact-button {
  min-height: 34px;
  padding: 7px 11px;
  border-radius: 9px;
  cursor: pointer;
  font-size: 12px;
  font-weight: 800;
  white-space: nowrap;
}
.nav-account-button {
  border: 1px solid rgba(255,255,255,.25);
  color: white;
  background: rgba(255,255,255,.07);
}
.nav-account-button:hover { border-color: rgba(121,217,255,.58); background: rgba(121,217,255,.10); }

.account-modal[hidden] { display: none; }
.account-modal {
  position: fixed;
  inset: 0;
  z-index: 105;
  display: grid;
  place-items: center;
  padding: 20px;
}
.account-modal-card {
  width: min(540px, 100%);
  max-height: min(760px, calc(100vh - 32px));
  position: relative;
  z-index: 1;
  overflow: auto;
  padding: 34px;
  border: 1px solid rgba(121,217,255,.24);
  border-radius: 22px;
  background:
    radial-gradient(circle at 100% 0%, rgba(121,217,255,.14), transparent 30%),
    white;
  box-shadow: 0 30px 90px rgba(2,18,31,.34);
}
.account-modal-card h2 {
  margin: 8px 0 10px;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: 34px;
  line-height: 1.12;
}
.account-intro { margin: 0; color: var(--muted); }
.account-tabs {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 6px;
  margin: 24px 0 18px;
  padding: 5px;
  border-radius: 12px;
  background: var(--soft);
}
.account-tab {
  min-height: 40px;
  border: 0;
  border-radius: 9px;
  color: var(--muted);
  background: transparent;
  cursor: pointer;
  font-weight: 800;
}
.account-tab.is-active { color: var(--navy); background: white; box-shadow: 0 5px 16px rgba(24,50,75,.08); }
.account-form { display: grid; gap: 15px; }
.account-form[hidden] { display: none; }
.account-form label { display: grid; gap: 6px; }
.account-form label > span { color: var(--navy); font-size: 13px; font-weight: 750; }
.account-form input {
  width: 100%;
  min-height: 46px;
  padding: 10px 12px;
  border: 1px solid #bcc9d3;
  border-radius: 10px;
  color: var(--ink);
  background: white;
  outline: none;
}
.account-form input:focus { border-color: var(--navy-2); box-shadow: 0 0 0 3px rgba(36,75,112,.10); }
.account-message {
  margin-top: 14px;
  padding: 11px 13px;
  border-radius: 10px;
  background: var(--soft);
  font-size: 14px;
}
.account-message.is-error { color: #8c3333; background: #fff0f0; }
.account-message.is-success { color: #246a50; background: #eefaf4; }
.account-privacy { margin: 16px 0 0; color: var(--muted); font-size: 12px; }
.account-user-actions,
.account-page-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 24px;
}

.account-page { display: grid; gap: 28px; }
.account-benefits {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}
.account-benefits article,
.account-page-panel,
.privacy-note,
.admin-login-card,
.admin-panel {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: white;
  box-shadow: 0 14px 38px rgba(24,50,75,.07);
}
.account-benefits article { padding: 22px; }
.account-benefits article > strong { color: var(--accent); font-size: 26px; }
.account-benefits h2 { margin: 10px 0 4px; color: var(--navy); font-size: 20px; }
.account-benefits p { margin: 0; color: var(--muted); }
.account-page-panel,
.privacy-note { padding: 28px; }
.account-page-panel h2,
.privacy-note h2 { margin: 7px 0 10px; color: var(--navy); font-family: Georgia, serif; font-size: 30px; }
.sync-status { color: var(--success); font-weight: 700; }
.danger-zone { margin-top: 30px; padding-top: 18px; border-top: 1px solid var(--line); }
.danger-zone summary { color: var(--danger); cursor: pointer; font-weight: 800; }
.danger-zone form { max-width: 420px; margin-top: 14px; display: grid; gap: 12px; }
.button.danger { color: white; background: var(--danger); }

.admin-login-card { max-width: 480px; margin: 0 auto; padding: 28px; }
.admin-dashboard { display: grid; gap: 26px; }
.admin-stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.admin-stats article {
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 15px;
  background: white;
  box-shadow: 0 10px 28px rgba(24,50,75,.06);
}
.admin-stats strong { display: block; color: var(--navy); font-family: Georgia, serif; font-size: 36px; }
.admin-stats span { color: var(--muted); font-size: 13px; }
.admin-columns { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; align-items: start; }
.admin-panel { overflow: hidden; }
.admin-panel-heading { display: flex; align-items: center; justify-content: space-between; gap: 18px; padding: 20px 22px; border-bottom: 1px solid var(--line); }
.admin-panel-heading h2 { margin: 0; color: var(--navy); font-size: 22px; }
.admin-panel-heading span { min-width: 34px; padding: 5px 9px; border-radius: 999px; text-align: center; color: var(--navy); background: var(--accent-soft); font-weight: 800; }
.admin-table-wrap { overflow-x: auto; }
.admin-panel table { width: 100%; border-collapse: collapse; font-size: 13px; }
.admin-panel th,
.admin-panel td { padding: 13px 16px; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
.admin-panel th { color: var(--muted); background: var(--soft); font-size: 11px; text-transform: uppercase; letter-spacing: .06em; }
.admin-panel td strong,
.admin-panel td small { display: block; }
.admin-panel td small { color: var(--muted); }
.admin-panel code { white-space: nowrap; }
.admin-panel .muted { padding: 22px; }
.admin-footer { display: flex; align-items: center; justify-content: space-between; gap: 20px; color: var(--muted); }

@media (max-width: 1120px) {
  .main-nav { gap: 9px; font-size: 11px; }
  .main-nav a { font-size: 11px; }
  .nav-account-button,
  .nav-contact-button { padding-inline: 8px; font-size: 11px; }
}

@media (max-width: 900px) {
  .menu-toggle { display: block; }
  .main-nav {
    display: none;
    position: absolute;
    left: 16px;
    right: 16px;
    top: 68px;
    padding: 16px;
    align-items: stretch;
    flex-direction: column;
    gap: 4px;
    border-radius: 14px;
    color: var(--ink);
    background: white;
    box-shadow: var(--shadow);
  }
  .main-nav.is-open { display: flex; }
  .main-nav a { padding: 10px; color: var(--navy); font-size: 13px; }
  .main-nav .nav-account-button,
  .main-nav .nav-contact-button {
    width: 100%;
    min-height: 42px;
    margin-top: 5px;
    color: var(--navy);
    border-color: #b9c7d2;
    background: white;
    font-size: 13px;
  }
  .main-nav .nav-contact-button { background: var(--accent); border-color: var(--accent); }
  .account-benefits { grid-template-columns: 1fr; }
  .admin-stats { grid-template-columns: repeat(2, 1fr); }
  .admin-columns { grid-template-columns: 1fr; }
}

@media (max-width: 560px) {
  .header-activity { right: 10px; bottom: 10px; padding: 8px 10px; font-size: 11px; }
  .account-modal { padding: 9px; }
  .account-modal-card { padding: 28px 20px 22px; }
  .account-modal-card h2 { font-size: 29px; }
  .account-user-actions,
  .account-page-actions { flex-direction: column; align-items: stretch; }
  .account-user-actions .button,
  .account-page-actions .button { width: 100%; }
  .admin-stats { grid-template-columns: 1fr 1fr; }
  .admin-stats article { padding: 16px; }
  .admin-stats strong { font-size: 30px; }
  .admin-footer { align-items: stretch; flex-direction: column; }
}


.hero-register-card {
  margin-top: 22px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 18px;
  padding: 18px 20px;
  border: 1px solid rgba(121,217,255,.22);
  border-radius: 18px;
  background: rgba(255,255,255,.08);
  backdrop-filter: blur(10px);
}
.hero-register-card strong { display: block; margin-bottom: 6px; color: white; font-size: 18px; }
.hero-register-card p { margin: 0; color: rgba(255,255,255,.76); font-size: 14px; max-width: 540px; }
.hero-profile-scene { min-height: 490px; }
.hero-portrait-shell {
  position: relative; z-index: 5; width: min(420px, 100%); aspect-ratio: 1 / 1;
  padding: 12px; border-radius: 50%; background: linear-gradient(145deg, rgba(239,176,47,.95), rgba(246,210,121,.92));
  box-shadow: 0 30px 72px rgba(0,0,0,.28), 0 0 0 18px rgba(239,176,47,.08);
}
.hero-portrait-shell::after { content: ''; position: absolute; inset: 24px; border-radius: 50%; border: 1px solid rgba(121,217,255,.40); pointer-events: none; }
.hero-portrait { width: 100%; height: 100%; object-fit: cover; border-radius: 50%; display: block; }
.hero-profile-note {
  position: absolute; z-index: 7; left: 8px; right: 8px; bottom: 18px; padding: 18px 20px;
  border: 1px solid rgba(255,255,255,.16); border-radius: 22px; background: rgba(8,30,50,.70); backdrop-filter: blur(10px);
  color: white; box-shadow: 0 20px 40px rgba(0,0,0,.18);
}
.hero-profile-note strong { display: block; font-size: 23px; line-height: 1.12; }
.hero-profile-note small { display: block; margin-top: 8px; color: rgba(255,255,255,.72); font-size: 13px; }
.author-photo-wrap { margin-bottom: 24px; }
.author-photo { width: 112px; height: 112px; object-fit: cover; border-radius: 50%; display: block; box-shadow: 0 14px 34px rgba(0,0,0,.12); border: 4px solid rgba(239,176,47,.42); }
@media (max-width: 900px) { .hero-register-card { flex-direction: column; align-items: flex-start; } }
@media (max-width: 560px) { .hero-register-card { padding: 16px; } .hero-register-card .button { width: 100%; } .hero-profile-note strong { font-size: 19px; } .author-photo { width: 96px; height: 96px; } }


/* v0.6 — выравнивание карточек, инструкция, юридический блок и аналитика */
.equation-preview {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  column-gap: .08em;
  row-gap: .18em;
  min-height: 54px;
  line-height: 1.16;
}
.equation-preview .math-frac {
  vertical-align: middle;
  transform: translateY(.02em);
}

.howto-hero-actions,
.legal-links,
.admin-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.howto-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 20px;
}
.howto-card {
  position: relative;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: white;
  box-shadow: 0 12px 32px rgba(24,50,75,.06);
}
.howto-number {
  width: 44px;
  height: 44px;
  display: grid;
  place-items: center;
  margin-bottom: 18px;
  border-radius: 50%;
  color: var(--navy);
  background: linear-gradient(145deg, var(--accent), var(--accent-2));
  font-family: Georgia, serif;
  font-size: 22px;
  font-weight: 800;
}
.howto-card h2,
.howto-card h3 { margin: 0 0 10px; color: var(--navy); }
.howto-card p { margin: 0; color: var(--muted); }
.howto-tip {
  margin-top: 20px;
  padding: 20px 22px;
  border: 1px solid rgba(239,176,47,.34);
  border-radius: 16px;
  background: linear-gradient(135deg, rgba(255,245,213,.78), rgba(235,248,252,.74));
}
.home-howto-link { margin-top: 24px; }
.legal-page { font-size: 17px; }
.legal-page h2 { margin-top: 36px; }
.legal-page h3 { margin-top: 26px; color: var(--navy); }
.legal-page code { word-break: break-word; }
.legal-updated { color: var(--muted); font-size: 14px; }
.footer-legal {
  border-top: 1px solid rgba(255,255,255,.12);
  margin-top: 30px;
  padding-top: 18px;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: 12px 22px;
  color: rgba(255,255,255,.54);
  font-size: 12px;
}
.footer-legal nav { display: flex; flex-wrap: wrap; gap: 14px; }
.footer-legal a { color: rgba(255,255,255,.72); }
.admin-stats.admin-stats-wide { grid-template-columns: repeat(4, minmax(0, 1fr)); }
.admin-panel-wide { grid-column: 1 / -1; }
.admin-chart { display: grid; gap: 11px; padding: 20px 22px; }
.admin-chart-row { display: grid; grid-template-columns: 92px 1fr 46px; gap: 12px; align-items: center; font-size: 13px; }
.admin-chart-bar { height: 10px; overflow: hidden; border-radius: 999px; background: var(--soft); }
.admin-chart-bar span { height: 100%; display: block; min-width: 2px; border-radius: inherit; background: linear-gradient(90deg, var(--accent), var(--cyan)); }
.admin-system {
  padding: 20px 22px;
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 14px;
}
.admin-system div { padding: 14px; border-radius: 13px; background: var(--soft); }
.admin-system strong,
.admin-system small { display: block; }
.admin-system strong { color: var(--navy); font-size: 16px; }
.admin-system small { margin-top: 5px; color: var(--muted); }
.status-good { color: #23734d !important; }
.status-warning { color: #9a5e00 !important; }
.admin-actions { padding: 0 22px 22px; }
@media (max-width: 900px) {
  .howto-grid { grid-template-columns: 1fr; }
  .admin-stats.admin-stats-wide { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .admin-system { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .admin-chart-row { grid-template-columns: 74px 1fr 36px; gap: 8px; }
  .howto-card { padding: 21px; }
}


/* v0.6.1: явный выход со страницы формулы */
.formula-return-row {
  padding-top: 24px;
  margin-bottom: 12px;
}
.formula-return-button {
  display: inline-flex;
  align-items: center;
  min-height: 42px;
  padding: 9px 15px;
  border: 1px solid var(--line);
  border-radius: 12px;
  color: var(--navy);
  background: white;
  box-shadow: 0 8px 22px rgba(24,50,75,.06);
  font-weight: 800;
  transition: transform .18s ease, border-color .18s ease, box-shadow .18s ease;
}
.formula-return-button:hover {
  transform: translateY(-1px);
  border-color: rgba(239,176,47,.70);
  box-shadow: 0 12px 28px rgba(24,50,75,.10);
}
.formula-page .formula-return-row + .breadcrumbs { padding-top: 0; }
.formula-bottom-return {
  margin-top: 18px;
  text-align: center;
}
.formula-bottom-return a {
  display: inline-flex;
  padding: 12px 16px;
  border-radius: 12px;
  color: var(--navy);
  background: var(--accent-soft);
  font-weight: 800;
}
@media (max-width: 560px) {
  .formula-return-row { padding-top: 16px; }
  .formula-return-button,
  .formula-bottom-return a {
    width: 100%;
    justify-content: center;
    text-align: center;
  }
}


.admin-chart-row-page { grid-template-columns: minmax(0, 1.35fr) minmax(120px, 1fr) 34px; align-items: center; gap: 14px; }
.admin-page-meta { min-width: 0; display: grid; gap: 3px; }
.admin-page-meta strong, .admin-page-meta small { display: block; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.admin-page-meta strong { color: var(--navy); font-size: 14px; font-weight: 700; }
.admin-page-meta small { color: var(--muted); font-size: 11px; }
.admin-panel td strong, .admin-panel td small { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
@media (max-width: 720px) { .admin-chart-row-page { grid-template-columns: 1fr; } .admin-chart-row-page > span:last-child { justify-self: end; } }


.admin-chart-row-page { grid-template-columns: minmax(0, 1.55fr) minmax(120px, 1fr) 34px; }
.admin-page-meta { min-width: 0; }
.admin-page-meta strong { display: block; min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: var(--navy); font-size: 14px; font-weight: 700; }
.admin-page-meta small { display: none; }


/* v0.6.4 — единая математическая ось в вариантах ответа */
.quiz-option {
  display: flex;
  align-items: center;
  justify-content: flex-start;
  flex-wrap: wrap;
  column-gap: .04em;
  row-gap: .22em;
  line-height: 1.18;
}
.quiz-option .math-frac,
.quiz-option .inline-frac {
  align-self: center;
  vertical-align: middle;
  transform: none;
  font-size: 1em;
}
.quiz-option .math-op,
.quiz-option .math-paren,
.quiz-option .vector-symbol,
.quiz-option .average-symbol {
  display: inline-flex;
  align-items: center;
  align-self: center;
  line-height: 1.18;
}
.quiz-option .math-frac-num,
.quiz-option .math-frac-den {
  line-height: 1.04;
}
.quiz-option .math-frac-num { padding-bottom: .10em; }
.quiz-option .math-frac-den { padding-top: .10em; }
@media (max-width: 560px) {
  .quiz-option { column-gap: .03em; row-gap: .26em; }
}


/* v0.6.5 — режим технического перерыва */
.maintenance-page {
  min-height: 100vh;
  margin: 0;
  color: var(--ink);
  background:
    radial-gradient(circle at 18% 20%, rgba(121,217,255,.20), transparent 28%),
    radial-gradient(circle at 82% 78%, rgba(239,176,47,.18), transparent 30%),
    linear-gradient(145deg, #102b46, #173f63 55%, #102b46);
}
.maintenance-shell {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 28px;
}
.maintenance-card {
  position: relative;
  width: min(680px, 100%);
  padding: 48px;
  overflow: hidden;
  border: 1px solid rgba(255,255,255,.18);
  border-radius: 28px;
  background: rgba(255,255,255,.96);
  box-shadow: 0 34px 90px rgba(0,0,0,.28);
  text-align: center;
}
.maintenance-orbit {
  position: absolute;
  width: 270px;
  height: 92px;
  right: -70px;
  top: 26px;
  border: 1px solid rgba(121,217,255,.34);
  border-radius: 50%;
  transform: rotate(18deg);
}
.maintenance-photo {
  position: relative;
  z-index: 1;
  width: 108px;
  height: 108px;
  margin: 0 auto 24px;
  display: block;
  object-fit: cover;
  object-position: center 28%;
  border: 5px solid rgba(239,176,47,.72);
  border-radius: 50%;
  box-shadow: 0 16px 38px rgba(24,50,75,.18);
}
.maintenance-card h1 {
  margin: 12px 0 18px;
  color: var(--navy);
  font-family: Georgia, serif;
  font-size: clamp(38px, 7vw, 62px);
  line-height: 1.02;
}
.maintenance-lead {
  margin: 0 auto;
  max-width: 560px;
  color: var(--navy);
  font-size: 20px;
  line-height: 1.55;
}
.maintenance-note {
  margin: 16px auto 0;
  max-width: 540px;
  color: var(--muted);
  line-height: 1.55;
}
.maintenance-actions {
  margin-top: 28px;
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 12px;
}
.maintenance-status {
  min-height: 24px;
  margin-top: 20px;
  color: var(--muted);
  font-size: 13px;
}
.maintenance-admin-panel { border-color: rgba(239,176,47,.45); }
.maintenance-admin-body {
  padding: 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}
.maintenance-admin-body strong { display: block; color: var(--navy); font-size: 20px; }
.maintenance-admin-body p { margin: 7px 0 0; color: var(--muted); }
.maintenance-admin-body small { display: block; margin-top: 10px; color: var(--muted); }
.maintenance-badge-on { color: #7f1d1d !important; background: #fee2e2 !important; }
.maintenance-badge-off { color: #166534 !important; background: #dcfce7 !important; }
@media (max-width: 680px) {
  .maintenance-card { padding: 38px 22px; }
  .maintenance-lead { font-size: 18px; }
  .maintenance-actions { align-items: stretch; flex-direction: column; }
  .maintenance-actions .button { width: 100%; }
  .maintenance-admin-body { align-items: stretch; flex-direction: column; }
  .maintenance-admin-body form, .maintenance-admin-body .button { width: 100%; }
}


/* v0.6.6 — центрирование и космический дизайн техперерыва */
.maintenance-page {
  position: relative;
  overflow-x: hidden;
  color: #eef5fb;
  background:
    radial-gradient(circle at 14% 18%, rgba(121,217,255,.24), transparent 24%),
    radial-gradient(circle at 84% 16%, rgba(239,176,47,.16), transparent 24%),
    radial-gradient(circle at 78% 76%, rgba(157,135,255,.16), transparent 30%),
    linear-gradient(145deg, #091a2d 0%, #102b46 42%, #173f63 100%);
}
.maintenance-page::before {
  content: "";
  position: fixed; inset: 0; pointer-events: none; opacity: .38;
  background-image:
    radial-gradient(circle at 8% 12%, rgba(255,255,255,.95) 0 1px, transparent 1.7px),
    radial-gradient(circle at 72% 22%, rgba(255,255,255,.9) 0 1px, transparent 1.6px),
    radial-gradient(circle at 32% 72%, rgba(121,217,255,.85) 0 1px, transparent 1.8px),
    radial-gradient(circle at 86% 74%, rgba(239,176,47,.82) 0 1px, transparent 1.9px);
  background-size: 120px 120px, 160px 160px, 220px 220px, 280px 280px;
}
.maintenance-shell {
  position: relative;
  z-index: 1;
  width: 100%;
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 42px 20px;
}
.maintenance-card.maintenance-cosmic-card {
  position: relative;
  width: min(760px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 44px 42px 36px;
  border: 1px solid rgba(255,255,255,.16);
  border-radius: 32px;
  background:
    linear-gradient(180deg, rgba(255,255,255,.97), rgba(249,251,255,.95));
  box-shadow: 0 34px 96px rgba(4, 16, 29, .34);
  text-align: center;
}
.maintenance-stars {
  position: absolute; inset: 0; pointer-events: none; opacity: .5;
  background-image:
    radial-gradient(circle at 15% 22%, rgba(121,217,255,.42) 0 1px, transparent 1.9px),
    radial-gradient(circle at 82% 20%, rgba(239,176,47,.45) 0 1px, transparent 1.9px),
    radial-gradient(circle at 24% 78%, rgba(157,135,255,.32) 0 1px, transparent 1.8px),
    radial-gradient(circle at 88% 76%, rgba(255,255,255,.68) 0 1px, transparent 1.9px);
  background-size: 120px 120px, 190px 190px, 250px 250px, 300px 300px;
}
.maintenance-orbit {
  width: 250px;
  height: 86px;
  border-color: rgba(121,217,255,.22);
}
.maintenance-orbit.orbit-a { right: -50px; top: 16px; transform: rotate(18deg); }
.maintenance-orbit.orbit-b { left: -66px; bottom: 110px; transform: rotate(-22deg); border-color: rgba(239,176,47,.18); }
.maintenance-photo {
  width: 146px; height: 146px; margin-bottom: 22px;
  border-width: 6px; border-color: rgba(239,176,47,.82);
  box-shadow: 0 18px 42px rgba(18,40,63,.20), 0 0 0 14px rgba(239,176,47,.08);
}
.maintenance-card .eyebrow { display: inline-block; margin-bottom: 10px; }
.maintenance-card h1 {
  margin: 8px 0 18px;
  font-size: clamp(38px, 6vw, 62px);
  line-height: 1.02;
}
.maintenance-highlight {
  margin: 0 auto;
  max-width: 620px;
  display: flex; align-items: center; justify-content: center; gap: 12px;
  padding: 16px 20px;
  border: 1px solid rgba(239,176,47,.32);
  border-radius: 22px;
  background: linear-gradient(135deg, rgba(255,245,214,.95), rgba(255,251,235,.98));
  box-shadow: inset 0 1px 0 rgba(255,255,255,.8);
}
.maintenance-emoji { font-size: 28px; line-height: 1; flex: 0 0 auto; }
.maintenance-lead {
  margin: 0;
  max-width: none;
  color: var(--navy);
  font-size: 21px;
  font-weight: 600;
  line-height: 1.6;
}
.maintenance-note { margin-top: 18px; font-size: 15px; }
.maintenance-actions { margin-top: 26px; }
.maintenance-status {
  margin-top: 18px;
  color: var(--muted);
  font-size: 14px;
}
@media (max-width: 720px) {
  .maintenance-card.maintenance-cosmic-card { padding: 34px 22px 28px; border-radius: 24px; }
  .maintenance-highlight { flex-direction: column; padding: 16px; }
  .maintenance-photo { width: 118px; height: 118px; }
  .maintenance-orbit.orbit-b { display: none; }
}


/* v0.6.7 — шлифовка блока техперерыва в админке */
.maintenance-admin-panel { border-color: rgba(239,176,47,.45); }
.maintenance-admin-body {
  padding: 26px 28px 30px;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
  text-align: center;
}
.maintenance-admin-copy {
  width: min(760px, 100%);
  padding: 18px 20px;
  border: 1px solid rgba(239,176,47,.24);
  border-radius: 22px;
  background: linear-gradient(135deg, rgba(255,247,223,.88), rgba(255,251,240,.96));
  box-shadow: inset 0 1px 0 rgba(255,255,255,.86);
}
.maintenance-admin-copy strong {
  display: block;
  margin-bottom: 8px;
  color: var(--navy);
  font-size: 24px;
  line-height: 1.2;
  font-family: Georgia, serif;
}
.maintenance-admin-copy p {
  margin: 0;
  color: var(--ink);
  line-height: 1.65;
  font-size: 16px;
}
.maintenance-admin-copy small {
  display: block;
  margin-top: 12px;
  color: var(--muted);
  font-size: 13px;
}
.maintenance-admin-actions {
  display: flex;
  justify-content: center;
  width: 100%;
}
.maintenance-admin-actions form { display: flex; justify-content: center; width: 100%; }
.maintenance-admin-actions .button {
  min-width: min(100%, 340px);
  justify-content: center;
  margin: 0 auto;
}
@media (max-width: 680px) {
  .maintenance-admin-body { padding: 22px 18px 24px; }
  .maintenance-admin-copy { padding: 16px; }
  .maintenance-admin-copy strong { font-size: 21px; }
  .maintenance-admin-actions .button { width: 100%; }
}