/* ==========================================================================
   РАДИОЭКЗАМЕН — образовательный дизайн.
   Спокойный электронный учебник: sans-serif интерфейс, serif-текст уроков,
   мягкие палитры, синий акцент. Без «радио»-стилизации.
   ========================================================================== */

:root {
  color-scheme: light;
  /* Light — основная тема */
  --page: #F6F7F8;
  --content: #FCFCFB;
  --card: #FFFFFF;
  --card-hover: #FAFBFC;
  --well: #F1F2F4;
  --note-bg: #F7F9FC;
  --note-line: #5B7CFA;
  --border: #E1E4E7;
  --border-strong: #D2D6DA;

  --heading: #1A1B1E;
  --text: #202124;
  --body: #202124;
  --secondary: #60676F;
  --muted: #858C94;
  --quiet: #A4A9AF;

  --blue: #4263EB;
  --blue-hover: #364FC7;
  --blue-soft: rgba(66, 99, 235, .08);
  --blue-line: rgba(66, 99, 235, .45);

  --green: #2F9E66;
  --green-soft: rgba(47, 158, 102, .09);
  --green-line: rgba(47, 158, 102, .4);
  --red: #D6453D;
  --red-soft: rgba(214, 69, 61, .08);
  --red-line: rgba(214, 69, 61, .4);

  --tip-bg: #FFFFFF;
  --tip-text: #3C4043;
  --tip-border: var(--border);

  --radius: 14px;
  --radius-sm: 9px;
  --mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
  --serif: Georgia, "Noto Serif", "Times New Roman", serif;
  --sans: Inter, system-ui, -apple-system, "Segoe UI", sans-serif;
}

:root[data-theme="dark"] {
  color-scheme: dark;
  --page: #17191C;
  --content: #1D2024;
  --card: #22262A;
  --card-hover: #252A2F;
  --well: #262A2F;
  --note-bg: #24282E;
  --note-line: #5C7CFA;
  --border: #30353A;
  --border-strong: #3B4147;

  --heading: #ECEEEF;
  --text: #DADDE0;
  --body: #C9CDD1;
  --secondary: #A6ABB0;
  --muted: #7D858D;
  --quiet: #686F76;

  --blue: #5C7CFA;
  --blue-hover: #6F8BFF;
  --blue-soft: rgba(92, 124, 250, .14);
  --blue-line: rgba(92, 124, 250, .5);

  --green: #4CC38A;
  --green-soft: rgba(76, 195, 138, .12);
  --green-line: rgba(76, 195, 138, .45);
  --red: #E0705F;
  --red-soft: rgba(224, 112, 95, .12);
  --red-line: rgba(224, 112, 95, .45);

  --tip-bg: #262A2F;
  --tip-text: #DADDE0;
  --tip-border: #3B4147;
}

* { box-sizing: border-box; }
html { background: var(--page); }
body {
  margin: 0;
  min-height: 100vh;
  color: var(--text);
  background: var(--page);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}
button, select, input { font: inherit; }
button { color: inherit; }
a { color: var(--blue); text-decoration: none; }
a:hover { color: var(--blue-hover); text-decoration: underline; }
code { font-family: var(--mono); font-size: .92em; }
.shell { min-height: 100vh; }

/* ------------------------------- Шапка ---------------------------------- */
.topbar {
  height: 68px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0 28px;
  border-bottom: 1px solid var(--border);
  background: color-mix(in srgb, var(--page) 88%, transparent);
  backdrop-filter: blur(14px);
  position: sticky;
  top: 0;
  z-index: 10;
}
.brand { display: flex; gap: 12px; align-items: center; padding: 0; border: 0; background: none; text-align: left; cursor: pointer; }
.brand-mark {
  width: 36px; height: 36px;
  display: grid; place-items: center;
  border-radius: 10px;
  background: var(--blue-soft);
}
.brand-mark svg { width: 21px; fill: none; stroke: var(--blue); stroke-width: 1.9; stroke-linecap: round; }
.brand strong { display: block; font-size: 15px; font-weight: 700; letter-spacing: -.1px; }
.brand small { display: block; color: var(--muted); font-size: 11.5px; margin-top: 1px; }
.top-actions { display: flex; align-items: center; gap: 10px; }
/* Профиль: круглый аватар с первой буквой + dropdown */
.profile-wrap { position: relative; }
.avatar-button {
  width: 34px; height: 34px;
  border: 1px solid transparent;
  border-radius: 50%;
  background: var(--blue-soft);
  color: var(--blue);
  font-size: 14px;
  font-weight: 650;
  cursor: pointer;
  display: inline-grid;
  place-items: center;
  transition: border-color .12s, background .12s;
}
.avatar-button:hover { border-color: var(--blue-line); }
.avatar-button:focus-visible { outline: 2px solid var(--blue); outline-offset: 2px; }
.profile-menu {
  position: absolute;
  right: 0;
  top: calc(100% + 10px);
  z-index: 60;
  min-width: 240px;
  padding: 6px;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--card);
  box-shadow: 0 12px 34px rgba(15, 25, 45, .14);
}
.profile-menu[hidden] { display: none; }
.profile-email {
  padding: 8px 12px 10px;
  margin-bottom: 4px;
  border-bottom: 1px solid var(--border);
  color: var(--secondary);
  font-size: 13.5px;
  line-height: 1.45;
  word-break: break-all;
}
.profile-logout {
  display: block;
  width: 100%;
  text-align: left;
  padding: 9px 12px;
  border: 0;
  border-radius: 8px;
  background: none;
  color: var(--text);
  cursor: pointer;
  font-size: 14.5px;
}
.profile-logout:hover { background: var(--well); }
.profile-logout:focus-visible { outline: 2px solid var(--blue); outline-offset: -2px; }

/* Тосты сохранения */
.toast-root {
  position: fixed;
  left: 50%;
  bottom: 28px;
  transform: translateX(-50%);
  z-index: 120;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  pointer-events: none;
}
.toast {
  display: flex;
  align-items: center;
  gap: 8px;
  max-width: min(420px, calc(100vw - 32px));
  padding: 10px 16px;
  border: 1px solid var(--border);
  border-radius: 10px;
  background: var(--card);
  box-shadow: 0 10px 30px rgba(15, 25, 45, .14);
  color: var(--text);
  font-size: 14.5px;
  line-height: 1.5;
  opacity: 0;
  transform: translateY(6px);
  transition: opacity .2s, transform .2s;
}
.toast.show { opacity: 1; transform: translateY(0); }
.toast-check { color: var(--green); font-weight: 700; }
.toast.error {
  border-color: var(--red-line);
  background: var(--red-soft);
  color: var(--red);
  font-weight: 550;
}
.nav-button {
  border: 1px solid var(--border);
  border-radius: 9px;
  padding: 7px 15px;
  background: var(--card);
  color: var(--text);
  font-size: 14px;
  font-weight: 550;
  cursor: pointer;
  transition: border-color .15s, background .15s, box-shadow .15s;
}
.nav-button:hover { border-color: var(--border-strong); background: var(--well); }
.exam-nav {
  background: var(--blue);
  border-color: transparent;
  color: #FFFFFF;
  font-weight: 600;
}
.exam-nav:hover { background: var(--blue-hover); border-color: transparent; color: #fff; }
.user-chip { color: var(--muted); font-size: 14px; }
.user-chip b { color: var(--text); font-weight: 600; }
.icon-button, .dialog-close {
  width: 34px; height: 34px;
  border: 1px solid var(--border);
  border-radius: 50%;
  background: var(--card);
  color: var(--secondary);
  cursor: pointer;
  display: inline-grid; place-items: center;
  font-size: 14px;
}
.icon-button:hover { border-color: var(--border-strong); background: var(--well); }

main { width: min(1200px, calc(100% - 48px)); margin: 0 auto; padding: 44px 0 96px; }
/* main фокусируется программно для скринридеров — кольцо фокуса не нужно */
main:focus { outline: none; }

/* ------------------------------ Типографика ----------------------------- */
.hero { margin-bottom: 30px; }
.eyebrow {
  margin: 0 0 8px;
  color: var(--muted);
  font-size: 13px;
  font-weight: 600;
  letter-spacing: 0;
}
h1 {
  margin: 0;
  font-size: clamp(38px, 4vw, 50px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.02em;
  color: var(--heading);
}
h2 {
  margin: 0;
  font-size: 28px;
  font-weight: 700;
  line-height: 1.25;
  letter-spacing: -.01em;
  color: var(--heading);
}
h3 {
  margin: 0;
  font-size: 20px;
  font-weight: 650;
  color: var(--heading);
}
.lead { max-width: 720px; margin: 12px 0 0; color: var(--secondary); font-size: 16px; line-height: 1.65; }

/* --------------------------- Главная: статистика ------------------------ */
.stats-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 12px; }
.stat-card {
  border: 1px solid var(--border);
  background: var(--card);
  border-radius: var(--radius);
  padding: 16px 18px;
}
.stat-card span { display: block; color: var(--muted); font-size: 13px; font-weight: 500; }
.stat-card strong {
  display: flex; align-items: baseline; gap: 2px;
  margin-top: 6px;
  font-size: 26px;
  font-weight: 650;
  letter-spacing: -.5px;
  color: var(--heading);
}
.stat-card small { color: var(--muted); font-size: 13px; }

/* Общий прогресс — тонкая полоса */
.progress-block {
  display: flex; align-items: center; gap: 16px;
  margin: 16px 0 4px;
}
.progress-block .pb-label { color: var(--secondary); font-size: 14px; font-weight: 550; white-space: nowrap; }
.progress-block .pb-count { color: var(--muted); font-size: 14px; font-variant-numeric: tabular-nums; white-space: nowrap; }
.progress-bar { flex: 1; height: 6px; border-radius: 99px; background: var(--well); overflow: hidden; min-width: 60px; }
.progress-fill { height: 100%; border-radius: 99px; background: var(--blue); transition: width .25s ease; }

.section-head { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin: 30px 0 14px; }
.section-head h2 { font-size: 27px; }
.section-head p { color: var(--muted); margin: 0; font-size: 14px; }
.reset-link { border: 0; padding: 4px 0; color: var(--red); background: none; cursor: pointer; font-size: 14px; }
.reset-link:hover { text-decoration: underline; }

/* ------------------------- Главная: режимы ------------------------------ */
.mode-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 14px; }
.mode-card {
  padding: 22px 22px 20px;
  min-height: 226px;
  display: flex;
  flex-direction: column;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
  transition: border-color .15s, box-shadow .15s, transform .15s;
}
.mode-card:hover { border-color: var(--border-strong); box-shadow: 0 4px 16px rgba(30, 40, 60, .06); transform: translateY(-1px); }
:root[data-theme="dark"] .mode-card:hover { box-shadow: 0 4px 16px rgba(0, 0, 0, .35); }
.mode-icon {
  width: 40px; height: 40px;
  display: grid; place-items: center;
  border-radius: 10px;
  color: var(--blue);
  background: var(--blue-soft);
}
.mode-icon svg { width: 21px; height: 21px; fill: none; stroke: currentColor; stroke-width: 1.7; stroke-linecap: round; stroke-linejoin: round; }
.mode-card h3 { margin-top: 16px; font-size: 19px; }
.mode-topic {
  display: inline-flex; align-self: flex-start;
  margin-top: 6px;
  color: var(--secondary);
  font-size: 13px;
  font-weight: 500;
}
.mode-card p { color: var(--secondary); font-size: 15px; line-height: 1.6; margin: 6px 0 0; flex: 1; }
.mode-actions { display: grid; gap: 9px; margin-top: 16px; }
.mode-actions small { color: var(--muted); text-align: center; font-size: 13px; }

/* ------------------------------ Кнопки ---------------------------------- */
.button {
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  padding: 10px 16px;
  background: var(--card);
  color: var(--text);
  cursor: pointer;
  font-size: 14.5px;
  font-weight: 550;
  transition: background .15s, border-color .15s, box-shadow .15s;
}
.button:hover { background: var(--well); border-color: var(--border-strong); }
.button.primary {
  background: var(--blue);
  border-color: transparent;
  color: #FFFFFF;
  font-weight: 600;
}
.button.primary:hover { background: var(--blue-hover); border-color: transparent; }
.button:disabled { opacity: .45; cursor: not-allowed; }
.button.full { width: 100%; }
.button.danger { color: var(--red); }
.button.danger:hover { background: var(--red-soft); border-color: transparent; }

/* ----------------------------- Темы-фильтры ----------------------------- */
.topic-panel { padding: 4px 0; }
.topic-list { display: flex; flex-wrap: wrap; gap: 8px; }
.topic-chip {
  padding: 7px 14px;
  border: 1px solid var(--border);
  border-radius: 99px;
  color: var(--secondary);
  background: var(--card);
  cursor: pointer;
  font-size: 14px;
  font-weight: 500;
  transition: border-color .15s, color .15s, background .15s;
}
.topic-chip:hover { color: var(--text); border-color: var(--border-strong); }
.topic-chip.active {
  color: var(--blue);
  border-color: var(--blue-line);
  background: var(--blue-soft);
  font-weight: 600;
}

/* ---------------------------- Страница уроков --------------------------- */
.lesson-list { display: grid; gap: 10px; margin-bottom: 12px; }
.lesson-card {
  position: relative;
  cursor: pointer;
  padding: 22px 24px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
}
.lesson-card:hover { border-color: var(--border-strong); background: var(--card-hover); }
.lesson-card:focus-within { border-color: var(--blue-line); box-shadow: 0 0 0 3px var(--blue-soft); }
.lesson-index { display: none; }
.lesson-card.active { border-color: var(--blue-line); }
.lesson-topic { display: block; color: var(--secondary); font-size: 13.5px; font-weight: 600; margin-bottom: 8px; }
.lesson-card h3 { font-size: 18.5px; line-height: 1.4; margin: 0; }
.lesson-card p { margin: 12px 0 0; color: var(--secondary); font-size: 15px; line-height: 1.6; max-width: 880px; }
.lesson-foot { display: flex; align-items: center; justify-content: space-between; gap: 12px; margin-top: 16px; }
.lesson-foot small { color: var(--muted); font-size: 13.5px; }
/* Текстовый action вместо кнопки-«формы»; кликабельна вся карточка */
.lesson-link {
  border: 0;
  background: none;
  padding: 4px 0;
  color: var(--blue);
  font-size: 14.5px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}
.lesson-link::after { content: ''; position: absolute; inset: 0; }
.lesson-link:hover { color: var(--blue-hover); text-decoration: underline; }
.lesson-link:focus-visible { outline: none; }

/* ----------------------- Страница урока: чтение ------------------------- */
/* Широкая «бумага» внутри широкого контейнера; текст — колонкой ~68ch.
   Никаких карточек-в-карточке: иерархия держится на типографике. */
.theory-page {
  max-width: 1200px;
  margin: 0 auto;
  background: var(--content);
  border: 1px solid var(--border);
  border-radius: 18px;
  padding: clamp(44px, 7vw, 92px) clamp(20px, 6vw, 96px);
}
/* Одна общая вертикальная ось. Каждый смысловой блок занимает всю «бумагу»,
   а его содержимое центрируется в единой колонке. Ширина колонки = 68ch
   текста статьи (19px Georgia ≈ 49.5rem) — задаётся в rem, а не в ch,
   чтобы у разных по кеглю элементов (H1/H2/врезки) колонка была ОДНОЙ. */
.theory-page > * { width: 100%; margin-inline: auto; }
.theory-hero > *, .theory-section > * {
  width: 100%;
  max-width: min(100%, 49.5rem);
  margin-inline: auto;
}
.theory-hero { padding: 0 0 10px; margin-bottom: 8px; }
.theory-hero .lead { font-size: 18px; }
.related-questions { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 24px; }
.related-questions span {
  padding: 4px 10px;
  border: 1px solid var(--border);
  border-radius: 99px;
  color: var(--muted);
  background: var(--card);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
}
/* Разделы статьи — поток текста, без рамок */
.theory-section {
  background: transparent;
  border: 0;
  border-radius: 0;
  padding: 0;
  margin: 0 0 20px;
}
.theory-section h2 {
  font-size: 30px;
  margin: 56px auto 18px;
}
.theory-section h2:first-child { margin-top: 28px; }
.theory-section h3 { font-size: 22px; margin: 36px auto 12px; }
.theory-section > p {
  color: var(--body);
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 400;
  line-height: 1.7;
  letter-spacing: 0;
  margin: 0 auto 1.25em;
  width: 100%;
}
/* Inline emphasis (Markdown **…**) меняет только насыщенность:
   шрифт, кегль, интерлиньяж и цвет наследуются от окружающего текста. */
.theory-section p strong, .theory-section p b,
.theory-section h3 strong, .theory-section h3 b,
.theory-section li strong, .theory-section li b {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  letter-spacing: inherit;
  color: inherit;
  font-weight: 600;
}
.theory-list { margin: 0 auto 1.25em; padding-left: 1.4em; }
.theory-list li {
  margin: 0 0 .7em;
  color: var(--body);
  font-family: var(--serif);
  font-size: 19px;
  line-height: 1.7;
}
/* Блоки-примеры и схемы: спокойный серый фон */
.theory-figure {
  margin: 20px auto 26px;
  padding: 18px 20px;
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--secondary);
  background: var(--well);
  font: 13.5px/1.7 var(--mono);
  white-space: pre;
}
/* Памятки — лёгкий callout: почти нейтральный фон + тонкая полоса слева.
   Текст памятки — тот же serif и кегль, что и у статьи. */
.memory-note {
  margin: 28px auto 30px;
  padding: 18px 22px;
  border-left: 3px solid var(--note-line);
  border-radius: 0 10px 10px 0;
  background: var(--note-bg);
  width: 100%;
}
.memory-note > strong {
  display: block;
  font: 600 14px/1.4 var(--sans);
  letter-spacing: 0;
  color: var(--heading);
  margin: 0 0 8px;
}
.memory-note > span {
  display: block;
  color: var(--body);
  font-family: var(--serif);
  font-size: 19px;
  font-weight: 400;
  line-height: 1.7;
}
.memory-note > span strong, .memory-note > span b {
  font-family: inherit;
  font-size: inherit;
  line-height: inherit;
  letter-spacing: inherit;
  color: inherit;
  font-weight: 600;
}
.theory-actions {
  max-width: min(100%, 49.5rem);
  margin: 44px auto 0;
  display: flex; justify-content: space-between; gap: 12px; flex-wrap: wrap;
}
/* Таблицы — в общей текстовой колонке (покрыты правилом .theory-section > *);
   на узких экранах шапки переносятся, скролл остаётся только как запасной. */
.table-scroll {
  margin: 24px auto 28px;
  overflow-x: auto;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
}
.theory-table { width: 100%; border-collapse: collapse; font-size: 14.5px; line-height: 1.55; }
.theory-table th, .theory-table td { padding: 11px 14px; border-bottom: 1px solid var(--border); text-align: left; vertical-align: top; }
.theory-table thead th { background: var(--well); color: var(--secondary); font-weight: 600; font-size: 13px; }
@media (max-width: 800px) {
  .theory-table th, .theory-table td { padding: 9px 10px; }
  .theory-table thead th { white-space: normal; }
  .theory-table td:first-child { white-space: normal; }
}
.theory-table tbody tr:last-child td { border-bottom: 0; }
.theory-table td:first-child { color: var(--heading); font-weight: 600; white-space: nowrap; }
.theory-table td:not(:first-child) { color: var(--secondary); }
.theory-table td:first-child + td { color: var(--muted); }

/* Термины-тултипы: обычный текст с пунктирным подчёркиванием */
.glossary-term {
  position: relative;
  color: inherit;
  border-bottom: 1px dotted var(--quiet);
  cursor: help;
  outline: none;
}
.glossary-term:hover, .glossary-term:focus { border-bottom-color: var(--blue); }
.glossary-tooltip {
  position: absolute;
  left: 50%; bottom: calc(100% + 8px);
  z-index: 30;
  width: min(320px, 80vw);
  padding: 11px 13px;
  border: 1px solid var(--tip-border);
  border-radius: var(--radius-sm);
  color: var(--tip-text);
  background: var(--tip-bg);
  box-shadow: 0 10px 30px rgba(20, 30, 50, .14);
  font-size: 13.5px;
  font-weight: 400;
  line-height: 1.55;
  font-family: var(--sans);
  transform: translate(-50%, 4px);
  opacity: 0;
  visibility: hidden;
  pointer-events: none;
  transition: opacity .14s, transform .14s, visibility .14s;
}
.glossary-tooltip strong { display: block; margin-bottom: 3px; color: var(--heading); font-size: 14px; }
.glossary-term:hover .glossary-tooltip, .glossary-term:focus .glossary-tooltip {
  opacity: 1; visibility: visible; transform: translate(-50%, 0);
}

/* ------------------------------ Словарик --------------------------------- */
.glossary-search {
  width: 100%;
  padding: 12px 16px;
  color: var(--text);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 10px;
  font-size: 15px;
  outline: none;
  margin-bottom: 18px;
  box-shadow: none;
}
.glossary-search:focus { border-color: var(--blue); box-shadow: 0 0 0 3px var(--blue-soft); }
.glossary-search::placeholder { color: var(--quiet); }
.glossary-list { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.glossary-entry {
  padding: 15px 17px;
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  background: var(--card);
}
.glossary-entry:hover { border-color: var(--border-strong); }
.glossary-entry h3 { font-size: 17px; font-weight: 650; margin: 0 0 5px; }
.glossary-entry p { margin: 0; color: var(--secondary); font-size: 15px; line-height: 1.55; }
.glossary-none { color: var(--muted); padding: 20px 0; text-align: center; grid-column: 1 / -1; }

/* --------------------------- Обучение / вопрос --------------------------- */
.quiz-header { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 16px; }
.quiz-meta { display: flex; align-items: baseline; gap: 10px; color: var(--secondary); font-size: 15px; }
.quiz-meta > span:first-child { font-weight: 650; color: var(--text); }
.quiz-meta .meta-count { color: var(--muted); font-variant-numeric: tabular-nums; font-weight: 550; }
.back-button { border: 0; background: none; color: var(--muted); padding: 6px 0; cursor: pointer; font-size: 15px; }
.back-button:hover { color: var(--blue); }
.progress-bar { margin-bottom: 18px; }
.progress-block .progress-bar { margin-bottom: 0; flex: 1; }

.quiz-layout { display: grid; grid-template-columns: minmax(0, 1fr) 250px; gap: 16px; align-items: start; }
.question-card {
  padding: clamp(24px, 4vw, 36px);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
}
.question-tags {
  display: flex; justify-content: space-between; gap: 12px;
  margin-bottom: 18px;
  color: var(--muted);
  font-size: 13.5px;
}
.question-text {
  font-size: 24px;
  font-weight: 600;
  line-height: 1.4;
  letter-spacing: -.2px;
  color: var(--heading);
  max-width: 720px;
}
.question-image { display: block; max-width: 100%; max-height: 360px; margin: 20px auto; border-radius: 8px; }
.question-card > * { max-width: 840px; margin-inline: auto; }
.answers { display: grid; gap: 12px; margin-top: 30px; }
.answer {
  width: 100%;
  display: flex;
  gap: 14px;
  align-items: center;
  position: relative;
  padding: 15px 20px;
  min-height: 56px;
  border: 1.5px solid var(--border);
  border-radius: 12px;
  color: var(--text);
  text-align: left;
  background: var(--card);
  cursor: pointer;
  line-height: 1.5;
  font-size: 17px;
  transition: border-color .12s, background .12s, box-shadow .12s;
}
.answer:hover { border-color: var(--blue); background: var(--blue-soft); }
.answer.selected { border-color: var(--blue); background: var(--blue-soft); }
.answer.correct { border-color: var(--green); background: var(--green-soft); }
.answer.correct::after { content: "✓"; margin-left: auto; color: var(--green); font-size: 19px; font-weight: 700; }
.answer.wrong { border-color: var(--red); background: var(--red-soft); }
.answer.wrong::after { content: "✕"; margin-left: auto; color: var(--red); font-size: 17px; font-weight: 700; }
.answer-key {
  width: 30px; height: 30px;
  flex: 0 0 auto;
  display: grid; place-items: center;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--secondary);
  font-size: 13px;
  font-weight: 650;
  background: var(--card);
}
.answer.correct .answer-key { border-color: var(--green); color: var(--green); }
.answer.wrong .answer-key { border-color: var(--red); color: var(--red); }
.feedback {
  margin-top: 16px;
  padding: 13px 17px;
  border-radius: 10px;
  font-size: 15.5px;
  line-height: 1.6;
  border: 1px solid transparent;
}
.feedback.good { color: var(--green); background: var(--green-soft); border-color: var(--green-line); }
.feedback.bad { color: var(--red); background: var(--red-soft); border-color: var(--red-line); }
.feedback strong { font-weight: 650; }
.question-actions { display: flex; justify-content: space-between; gap: 12px; margin-top: 22px; }

/* Боковая панель */
.side-panel { padding: 20px; position: sticky; top: 90px; background: var(--card); }
.side-panel h3 { margin-bottom: 10px; font-size: 14px; font-weight: 650; color: var(--heading); }
.side-panel p { color: var(--secondary); font-size: 13.5px; line-height: 1.6; }
.side-panel b { color: var(--text); font-weight: 600; }
.timer { font-size: 26px; font-weight: 650; letter-spacing: -.4px; margin: 4px 0 10px; color: var(--heading); font-variant-numeric: tabular-nums; }
.timer.urgent { color: var(--red); }
.exam-note { margin-top: 12px; color: var(--muted); font-size: 13px; line-height: 1.55; }
.side-panel .exam-note { margin: 14px 0 0; font-size: 12.5px; border-top: 1px solid var(--border); padding-top: 14px; }
.question-map { display: grid; grid-template-columns: repeat(5, 1fr); gap: 6px; }
.map-button {
  aspect-ratio: 1;
  border: 1px solid var(--border);
  border-radius: 7px;
  background: var(--card);
  color: var(--muted);
  font-size: 13px;
  font-variant-numeric: tabular-nums;
  cursor: pointer;
}
.map-button.answered { color: var(--blue); border-color: var(--blue-line); background: var(--blue-soft); font-weight: 600; }
.map-button.current { outline: 2px solid var(--blue); outline-offset: 1px; }

/* ------------------------------ Результаты ------------------------------ */
.result-card {
  max-width: 660px;
  margin: 30px auto;
  padding: 40px;
  text-align: center;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  background: var(--card);
}
.result-score { font-size: 62px; font-weight: 700; letter-spacing: -2px; margin: 16px 0 4px; }
.result-card.pass .result-score { color: var(--green); }
.result-card.fail .result-score { color: var(--red); }
.result-card > p { color: var(--secondary); line-height: 1.6; font-size: 15px; }
.result-card > .exam-note { max-width: 460px; margin: 14px auto 0; }
.result-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 10px; margin: 22px 0; }
.result-grid div { padding: 14px; border-radius: var(--radius-sm); background: var(--well); }
.result-grid strong { display: block; font-size: 22px; font-weight: 650; color: var(--heading); font-variant-numeric: tabular-nums; }
.result-grid span { color: var(--muted); font-size: 13px; }

.empty { padding: 60px 24px; text-align: center; }
.empty h2 { margin-bottom: 10px; }
.empty p { color: var(--secondary); font-size: 15px; }
.empty .button { margin-top: 16px; }

/* ------------------------------ Авторизация ------------------------------ */
.auth-wrap { display: grid; place-items: center; padding-top: 6vh; }
.auth-card { width: min(440px, 100%); padding: 36px; background: var(--card); }
.auth-card h2 { font-size: 28px; margin: 0 0 6px; }
.auth-card .lead { font-size: 15px; }
.auth-field { display: block; margin-top: 16px; color: var(--secondary); font-size: 14px; font-weight: 550; }
.auth-field input {
  width: 100%;
  margin-top: 6px;
  padding: 11px 14px;
  color: var(--text);
  background: var(--content);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  font-size: 16px;
  outline: none;
  font-weight: 400;
}
.auth-field input:focus { border-color: var(--blue); box-shadow: 0 0 0 3px var(--blue-soft); }
.auth-field input::placeholder { color: var(--quiet); }
.auth-error {
  margin: 14px 0 0; padding: 11px 13px;
  border-radius: var(--radius-sm);
  color: var(--red); background: var(--red-soft);
  border: 1px solid var(--red-line);
  font-size: 14px; line-height: 1.5;
}
.auth-card form button { margin-top: 20px; }
.auth-switch { display: block; margin: 16px auto 0; border: 0; background: none; color: var(--blue); cursor: pointer; font-size: 14.5px; }
.auth-switch:hover { text-decoration: underline; }

/* ------------------------------ Диалог ----------------------------------- */
dialog {
  position: relative;
  width: min(560px, calc(100% - 32px));
  color: var(--text);
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 30px;
  box-shadow: 0 24px 70px rgba(20, 30, 50, .2);
}
dialog::backdrop { background: rgba(25, 30, 40, .4); backdrop-filter: blur(3px); }
dialog h2 { margin-bottom: 12px; font-size: 24px; }
dialog p { color: var(--secondary); line-height: 1.65; font-size: 15px; }
dialog .muted { color: var(--muted); font-size: 13.5px; }
.dialog-close { position: absolute; right: 16px; top: 16px; }
.settings-row { display: flex; gap: 10px; align-items: center; margin-top: 14px; }
.settings-row select { flex: 1; color: var(--secondary); background: var(--content); border: 1px solid var(--border); border-radius: var(--radius-sm); padding: 9px; }

/* ------------------------------ Футер и правовые страницы ---------------- */
.site-footer {
  margin-top: 12px;
  padding: 20px 28px 26px;
  border-top: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  gap: 5px;
  align-items: center;
  color: var(--muted);
  font-size: 13.5px;
  text-align: center;
}
.footer-copy { color: var(--quiet); font-size: 12.5px; max-width: 720px; line-height: 1.5; }
.footer-links { display: inline-flex; gap: 14px; }
.footer-links button, .auth-consent button {
  border: 0; background: none; padding: 2px 0;
  color: var(--secondary); cursor: pointer; font-size: 13.5px;
}
.footer-links button:hover { color: var(--blue); text-decoration: underline; }
.legal-page { max-width: 860px; }
.legal-section h2 { font-size: 22px; margin: 34px 0 12px; }
.legal-section p {
  color: var(--body);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
  margin: 0 0 1em;
  max-width: 740px;
}
.legal-list { margin: 0 0 1em; padding-left: 22px; max-width: 740px; }
.legal-list li { color: var(--body); font-family: var(--sans); font-size: 16px; line-height: 1.65; margin-bottom: .55em; }
.legal-page .memory-note { max-width: 740px; }
.legal-page .memory-note > span {
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.65;
}
.auth-consent {
  margin: 14px auto 0;
  color: var(--muted);
  font-size: 13px;
  line-height: 1.55;
  text-align: center;
  max-width: 360px;
}
.auth-consent button { font-size: 13px; }
.auth-consent button:hover { color: var(--blue); text-decoration: underline; }

/* ------------------------------ Адаптив ---------------------------------- */
@media (max-width: 1100px) {
  .stats-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 900px) {
  .mode-grid { grid-template-columns: 1fr; }
  .mode-card { min-height: 0; }
  .glossary-list { grid-template-columns: 1fr; }
  .quiz-layout { grid-template-columns: 1fr; }
  .side-panel { position: static; }
}
@media (max-width: 800px) {
  .theory-page { padding: 34px 24px; }
  .theory-section h2 { font-size: 26px; }
  .question-text { font-size: 22px; }
}
@media (max-width: 560px) {
  .topbar { height: 58px; padding: 0 10px; }
  .sync-state, .user-chip { display: none; }
  .avatar-button { width: 30px; height: 30px; font-size: 13px; }
  .brand { gap: 7px; }
  .brand-mark { width: 31px; height: 31px; }
  .brand-text strong { font-size: 13.5px; }
  .brand-text small { display: none; }
  .nav-button { padding: 5px 10px; font-size: 13px; }
  .icon-button { width: 30px; height: 30px; }
  .top-actions { gap: 5px; }
  main { width: min(100% - 32px, 1200px); padding-top: 28px; }
  .stats-grid { gap: 8px; }
  .stat-card { padding: 14px; }
  .question-card { padding: 20px 16px; }
  .question-card > * { max-width: none; }
  .answer { padding: 13px 16px; font-size: 17px; min-height: 54px; }
  .question-text { font-size: 21px; line-height: 1.4; }
  .quiz-header { align-items: flex-start; }
  .result-card { padding: 26px 18px; }
  .theory-actions { flex-direction: column-reverse; }
  .theory-actions .button { width: 100%; }
  .theory-section > p, .theory-list li { font-size: 17px; line-height: 1.65; }
  .theory-page { padding: 26px 18px; border-radius: 14px; }
  .site-footer { padding: 18px 16px 22px; text-align: center; }
}
@media (max-width: 370px) {
  .brand-text { display: none; }
  .topbar { padding: 0 10px; }
}