/* ---------- theme variables ---------- */

:root {
  --bg: #0f1115;
  --sidebar-bg: #12151b;
  --panel: #171a21;
  --panel-2: #1f242e;
  --border: #2a2f37;
  --border-soft: #232830;
  --text: #e6e6e6;
  --muted: #9aa0a6;
  --faint: #6f767e;
  --accent: #4c8dff;
  --accent-hover: #3a7ae8;
  --accent-text: #ffffff;
  --green: #2e7d4f;
  --green-hover: #276a44;
  --amber: #d9a441;
  --error: #ff6b6b;
  --active-bg: #2b3b58;
  --shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
  --np-cover-grad: linear-gradient(135deg, #4c8dff, #7b5cff);
  /* Слайды и меню — тёмная «слайдовая» палитра в dark-теме */
  --s-bg: #0b1217;
  --s-panel: #121e26;
  --s-panel2: #192a33;
  --s-accent: #8fe3bf;
  --s-accent-a35: rgba(143, 227, 191, 0.35);
  --s-accent-a4: rgba(143, 227, 191, 0.4);
  --s-accent-a45: rgba(143, 227, 191, 0.45);
  --s-text: #f0f5f3;
  --s-muted: #9baeb6;
  --s-border: #30444e;
  --s-amber: #f1be72;
  --s-amber-a45: rgba(241, 190, 114, 0.45);
  --s-amber-bg: #3a2b1d;
  --s-green: #193a32;
  /* Подсветка синтаксиса Rust на слайдах */
  --s-blue: #82b8e8;
  --s-violet: #c9a7f0;
  --s-red: #ee8d86;
  /* «чёрные» узлы схем (красно-чёрные деревья) и текст на них */
  --s-ink: #05090c;
  --s-onink: #f0f5f3;
}

:root[data-theme="light"] {
  --bg: #f5f6f8;
  --sidebar-bg: #ffffff;
  --panel: #ffffff;
  --panel-2: #eef1f5;
  --border: #e2e6eb;
  --border-soft: #e8ebef;
  --text: #1c2026;
  --muted: #6b7280;
  --faint: #9aa1ab;
  --accent: #3a7ae8;
  --accent-hover: #2d66c9;
  --accent-text: #ffffff;
  --green: #27965c;
  --green-hover: #1f7d4b;
  --amber: #c98f1f;
  --error: #d93025;
  --active-bg: #dfe9ff;
  --shadow: 0 12px 40px rgba(16, 24, 40, 0.14);
  --np-cover-grad: linear-gradient(135deg, #5b95ff, #8f6fff);
  /* Слайды и меню — светлые значения той же палитры */
  --s-bg: #f6f8f7;
  --s-panel: #ffffff;
  --s-panel2: #e9f0ec;
  --s-accent: #177a4e;
  --s-accent-a35: rgba(23, 122, 78, 0.3);
  --s-accent-a4: rgba(23, 122, 78, 0.35);
  --s-accent-a45: rgba(23, 122, 78, 0.4);
  --s-text: #17232b;
  --s-muted: #5e6d75;
  --s-border: #d3dee2;
  --s-amber: #a5720e;
  --s-amber-a45: rgba(165, 114, 14, 0.4);
  --s-amber-bg: #f8eed9;
  --s-green: #dff0e8;
  /* Подсветка синтаксиса Rust на слайдах */
  --s-blue: #2f6bb0;
  --s-violet: #7d4fc9;
  --s-red: #c24842;
  --s-ink: #17232b;
  --s-onink: #f6f8f7;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family:
    system-ui,
    -apple-system,
    sans-serif;
  background: var(--bg);
  color: var(--text);
}

button {
  font-family: inherit;
}

.app {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ---------- topbar ---------- */

.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 0.7rem 1.4rem;
  background: var(--sidebar-bg);
  border-bottom: 1px solid var(--border);
}

.logo {
  border: none;
  background: transparent;
  color: var(--text);
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  cursor: pointer;
  padding: 0.25rem 0.5rem;
  border-radius: 8px;
}

.logo:hover {
  background: var(--panel-2);
}

.topbar-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

/* ---------- layout ---------- */

.layout {
  display: flex;
  flex: 1;
  min-height: 0;
}

/* ---------- sidebar ---------- */

.sidebar {
  width: 300px;
  flex-shrink: 0;
  background: var(--s-bg);
  border-right: 1px solid var(--s-border);
  padding: 1.2rem 0.8rem;
  overflow-y: auto;
  max-height: 100vh;
  position: sticky;
  top: 0;
}

.sidebar .s-label {
  padding: 4px 10px 8px;
  color: var(--s-accent);
}

.sidebar {
  transition:
    width 0.2s ease,
    padding 0.2s ease;
}

.sidebar.collapsed {
  width: 64px;
  padding-left: 0;
  padding-right: 0;
}

.aside-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.sidebar.collapsed .aside-head {
  justify-content: flex-start;
  padding-left: 16px;
  margin-bottom: 8px;
}

.aside-toggle,
.aside-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  padding: 0;
  border: 1px solid var(--s-border);
  border-radius: 10px;
  background: var(--s-panel);
  color: var(--s-muted);
  cursor: pointer;
  transition:
    color 0.15s,
    border-color 0.15s,
    background 0.15s;
}

.aside-toggle {
  width: 30px;
  height: 30px;
  margin-bottom: 6px;
  border-radius: 8px;
}

.sidebar.collapsed .aside-toggle {
  margin-bottom: 0;
}

.aside-toggle:hover,
.aside-icon:hover {
  color: var(--s-text);
  border-color: var(--s-accent-a45);
}

.aside-icon.on {
  color: var(--s-accent);
  border-color: var(--s-accent);
  background: var(--s-green);
}

.sidebar.collapsed .menu {
  align-items: flex-start;
  gap: 8px;
  padding-left: 13px;
}

.btn-icon {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  padding: 0;
  border: 1px solid var(--s-border);
  border-radius: 8px;
  background: var(--s-bg);
  color: var(--s-text);
  cursor: pointer;
  text-decoration: none;
  transition:
    background 0.15s,
    border-color 0.15s;
}

.btn-icon svg {
  width: 16px;
  height: 16px;
}

.btn-icon:hover {
  background: var(--s-panel2);
}

.btn-icon.on {
  border-color: var(--s-accent);
  color: var(--s-accent);
}

.menu {
  align-items: center;
  gap: 8px;
}

.menu {
  display: flex;
  flex-direction: column;
  gap: 0.2rem;
}

/* пункты меню разделов — по левому краю, номера в один столбец */
.sidebar:not(.collapsed) .menu /* дерево слева в полноэкранном режиме: разделы → главы → слайды */

.fst-sec {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin-bottom: 6px;
}

.fst-sec-head {
  display: flex;
  align-items: center;
  gap: 6px;
  padding: 6px 8px;
  background: transparent;
  border: none;
  color: var(--s-accent);
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  letter-spacing: 1.2px;
  text-transform: uppercase;
  text-align: left;
  cursor: pointer;
}

.fst-chev {
  display: inline-block;
  width: 10px;
  transition: transform 0.15s;
}

.fst-chev.open {
  transform: rotate(90deg);
}

.fst-slides {
  display: flex;
  flex-direction: column;
  gap: 1px;
  margin: 2px 0 6px 14px;
  padding-left: 8px;
  border-left: 1px solid var(--s-border);
}

.fst-slide {
  display: flex;
  align-items: baseline;
  gap: 8px;
  padding: 5px 8px;
  background: transparent;
  border: none;
  border-radius: 6px;
  color: var(--s-muted);
  font-family: "Inter", sans-serif;
  font-size: 12.5px;
  text-align: left;
  cursor: pointer;
  transition:
    background 0.15s,
    color 0.15s;
}

.fst-slide:hover {
  color: var(--s-text);
  background: var(--s-panel2);
}

.fst-slide.on {
  color: var(--s-accent);
  background: var(--s-green);
}

.fst-slide-num {
  flex-shrink: 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  opacity: 0.7;
}

/* плеер остаётся виден и поверх полноэкранных слайдов (см. .np-card) */
body:has(.np-card) .slide-fs {
  padding-bottom: 112px;
}

.slide-fs-toc-item {
  justify-content: flex-start;
  width: 100%;
  text-align: left;
}

.sidebar:not(.collapsed) .menu .slide-fs-toc-num {
  width: 18px;
}

.sidebar:not(.collapsed) .menu .slide-fs-toc-name {
  text-align: left;
}

/* ---------- home — стилистика слайдов ---------- */

.home h2 {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--s-muted);
  margin: 0 0 1rem;
}

/* ---------- content ---------- */

.content {
  flex: 1;
  min-width: 0;
  padding: 1.6rem 2rem 8rem;
  max-width: 980px;
}

h2 {
  font-size: 1.25rem;
  margin: 0 0 1rem;
}

.crumbs {
  margin: 0 0 0.3rem;
  color: var(--muted);
  font-size: 0.85rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}

.error {
  color: var(--error);
  margin: 0.6rem 0 0;
}

.empty {
  color: var(--muted);
}

/* ---------- now playing card — стилистика слайдов ---------- */

.np-card {
  position: fixed;
  bottom: 1rem;
  left: 50%;
  transform: translateX(-50%);
  width: min(720px, calc(100vw - 2rem));
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  padding: 0.9rem 1.1rem 0.8rem;
  z-index: 1100;
}

.np-main {
  display: flex;
  align-items: center;
  gap: 0.9rem;
}

.np-cover {
  width: 56px;
  height: 56px;
  flex-shrink: 0;
  border-radius: 10px;
  background: var(--s-green);
  border: 1px solid var(--s-accent-a35);
  color: var(--s-accent);
  font-family: "IBM Plex Mono", monospace;
  font-size: 1.3rem;
  font-weight: 500;
  display: flex;
  align-items: center;
  justify-content: center;
}

.np-info {
  min-width: 0;
  flex: 1;
}

.np-title {
  margin: 0;
  font-weight: 600;
  color: var(--s-text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.np-subtitle {
  margin: 0.2rem 0 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  letter-spacing: 0.3px;
  color: var(--s-muted);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.np-controls {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  flex-shrink: 0;
}

.np-btn {
  width: 40px;
  height: 34px;
  border-radius: 7px;
  border: 1px solid var(--s-border);
  background: var(--s-panel);
  color: var(--s-muted);
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition:
    color 0.2s,
    border-color 0.2s;
}

.np-btn:hover {
  color: var(--s-accent);
  border-color: var(--s-accent-a45);
}

.np-play {
  width: 48px;
  height: 38px;
  background: var(--s-green);
  border-color: var(--s-accent-a45);
  color: var(--s-accent);
}

.np-play:hover {
  background: var(--s-green);
  border-color: var(--s-accent);
}

.np-slider-row {
  display: flex;
  align-items: center;
  gap: 0.7rem;
  margin-top: 0.75rem;
}

.np-time {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  color: var(--s-muted);
  min-width: 2.6rem;
  text-align: center;
  font-variant-numeric: tabular-nums;
}

.np-slider {
  flex: 1;
  height: 8px;
  border-radius: 4px;
  background: var(--s-panel2);
  border: 1px solid var(--s-border);
  cursor: pointer;
  position: relative;
}

.np-slider-fill {
  height: 100%;
  border-radius: 2px;
  background: var(--s-accent);
  pointer-events: none;
}

.np-slider-knob {
  position: absolute;
  top: 50%;
  width: 12px;
  height: 12px;
  border-radius: 50%;
  background: var(--s-accent);
  border: 2px solid var(--s-panel);
  transform: translate(-50%, -50%);
  pointer-events: none;
}

/* ---------- narrow screens ---------- */

@media (max-width: 760px) {
  .topbar {
    padding: 0.6rem 0.8rem;
  }

  .layout {
    flex-direction: column;
  }

  .sidebar {
    width: 100%;
    max-height: 40vh;
    position: static;
    border-right: none;
    border-bottom: 1px solid var(--border);
  }

  .content {
    padding: 1.2rem;
  }

  .np-card {
    bottom: 0.5rem;
  }
}

/* ---------- lessons menu (layout column) ---------- */

.lessons-menu {
  width: 300px;
  flex-shrink: 0;
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 1.2rem 0.8rem;
  overflow-y: auto;
  max-height: 100vh;
  position: sticky;
  top: 0;
  background: var(--s-bg);
  border-right: 1px solid var(--s-border);
}

.lessons-menu .s-label {
  padding: 4px 10px 8px;
  color: var(--s-accent);
}

.lessons-group {
  display: flex;
  flex-direction: column;
  gap: 4px;
  margin-bottom: 12px;
}

.lessons-sec {
  padding: 6px 10px 4px;
  opacity: 0.85;
}

.lessons-menu .slide-fs-toc-item {
  text-align: left;
  font-size: 12.5px;
  padding: 7px 10px;
}

@media (max-width: 760px) {
  .lessons-menu {
    width: 100%;
    position: static;
    max-height: 40vh;
    border-right: none;
    border-bottom: 1px solid var(--s-border);
  }
}

.slide-panel {
  display: flex;
  flex-direction: column;
  gap: 10px;
  width: 100%;
  max-width: 860px;
  margin: 0 auto;
  max-height: calc(100vh - 140px);
  overflow-y: auto;
  padding: 14px;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 16px;
}

.slide-panel-head {
  display: flex;
  align-items: center;
  gap: 8px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  letter-spacing: 1px;
  color: var(--s-muted);
}

.slide-panel-head .slide-panel-num {
  margin-right: auto;
}

.slide-panel-num {
  color: var(--s-accent);
}

.s-time-mono {
  font-family: "IBM Plex Mono", monospace;
  font-variant-numeric: tabular-nums;
}

.slide-stage {
  display: flex;
  justify-content: center;
}

.slide-stage .slide {
  width: 100%;
  max-width: 780px;
}

.slide-dots {
  display: flex;
  flex-wrap: wrap;
  gap: 7px;
  justify-content: center;
  padding-top: 4px;
}

.slide-dot {
  width: 9px;
  height: 9px;
  border-radius: 50%;
  border: none;
  padding: 0;
  cursor: pointer;
  background: var(--s-border);
  transition:
    background 0.2s,
    transform 0.2s;
}

.slide-dot:hover {
  background: var(--s-muted);
}

.slide-dot.on {
  background: var(--s-accent);
  transform: scale(1.25);
}

/* ---------- slide internals ---------- */

.slide {
  display: flex;
  flex-direction: column;
  gap: 10px;
  padding: 16px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 14px;
  color: var(--s-text);
  font-family: "Inter", sans-serif;
  animation: slide-in 0.3s ease both;
}

@keyframes slide-in {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.s-rubric {
  display: flex;
  justify-content: space-between;
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 1.5px;
  color: var(--s-muted);
}

.s-title {
  margin: 0;
  font-size: 17px;
  font-weight: 600;
  color: var(--s-text);
}

.s-sub {
  margin: 0;
  font-size: 12px;
  color: var(--s-muted);
}

.s-divider {
  height: 1px;
  background: var(--s-border);
}

.s-body {
  display: flex;
  flex-direction: column;
  gap: 12px;
  font-size: 13px;
  line-height: 1.45;
}

.s-main {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 10px 12px;
  background: var(--s-green);
  border: 1px solid var(--s-accent-a35);
  border-radius: 10px;
}

.s-main-label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 9px;
  letter-spacing: 2px;
  color: var(--s-accent);
}

.s-main-text {
  font-size: 13px;
  font-weight: 500;
}

.s-grid2 {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

.s-topic {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 12px;
  background: var(--s-panel2);
  border: 1px solid var(--s-border);
  border-radius: 10px;
}

.s-topic-big {
  font-family: "IBM Plex Mono", monospace;
  font-size: 16px;
  color: var(--s-accent);
}

.s-cols {
  display: flex;
  align-items: center;
  gap: 10px;
}

.s-cols > * {
  min-width: 0;
}

.s-node {
  display: flex;
  flex-direction: column;
  gap: 3px;
  flex: 1;
  min-width: 0;
  padding: 10px 12px;
  background: var(--s-panel2);
  border: 1px solid var(--s-border);
  border-radius: 10px;
}

.s-node.green {
  background: var(--s-green);
  border-color: var(--s-accent-a45);
}

.s-node.amber {
  background: var(--s-amber-bg);
  border-color: var(--s-amber-a45);
}

.s-node-title {
  font-size: 13px;
  font-weight: 600;
  color: var(--s-text);
}

.s-node-sub {
  font-size: 11.5px;
  color: var(--s-muted);
}

.s-node-mono {
  font-family: "IBM Plex Mono", monospace;
  font-size: 13px;
  color: var(--s-accent);
}

.s-cmd {
  padding: 10px 12px;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
}

/* ---------- Rust code с подсветкой синтаксиса ---------- */

.rs-code {
  margin: 0;
  padding: 12px 14px;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 13px;
  line-height: 1.55;
  color: var(--s-text);
  overflow-x: auto;
  white-space: pre;
}

.rs-kw {
  color: var(--s-accent);
}

.rs-ty {
  color: var(--s-amber);
}

.rs-str {
  color: var(--s-blue);
}

.rs-num {
  color: var(--s-violet);
}

.rs-life {
  color: var(--s-violet);
  font-style: italic;
}

.rs-com {
  color: var(--s-muted);
  font-style: italic;
}

.rs-mac {
  color: var(--s-amber);
}

.rs-fn {
  color: var(--s-text);
  font-weight: 500;
}

.s-cmd pre {
  margin: 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  color: var(--s-accent);
  white-space: pre-wrap;
  word-break: break-word;
}

.s-arr {
  align-self: center;
  flex-shrink: 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 16px;
  color: var(--s-accent);
}

.s-label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--s-muted);
}

.s-table {
  display: flex;
  flex-direction: column;
}

.s-table > div {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: 12px;
  padding: 6px 4px;
  border-bottom: 1px solid var(--s-border);
}

.s-table > div:last-child {
  border-bottom: none;
}

.s-table span:first-child {
  text-align: left;
}

.s-table span:last-child {
  text-align: right;
}

.s-note {
  padding: 10px 12px;
  background: var(--s-panel);
  border-left: 3px solid var(--s-accent);
  border-radius: 8px;
  font-size: 12.5px;
  color: var(--s-muted);
}

.s-note.amber {
  border-left-color: var(--s-amber);
}

.s-path {
  display: inline-block;
  padding: 2px 8px;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 6px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  color: var(--s-text);
}

.s-path.accent {
  color: var(--s-accent);
  border-color: var(--s-accent-a4);
}

.s-hint {
  margin: 0;
  font-size: 12px;
  color: var(--s-muted);
}

/* ---------- fullscreen slides — always dark ---------- */

.slide-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  padding: 5px 9px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 7px;
  color: var(--s-muted);
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  letter-spacing: 0.5px;
  cursor: pointer;
  transition:
    color 0.2s,
    border-color 0.2s;
}

.slide-btn:hover {
  color: var(--s-accent);
  border-color: var(--s-accent-a45);
}

.slide-fs {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  gap: 20px;
  padding: 24px clamp(16px, 3vw, 40px) 20px;
  background: var(--s-bg);
  overflow: hidden;
}

.slide-fs-main {
  flex: 1;
  min-width: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
  overflow: hidden;
}

.slide-fs-body {
  flex: 1;
  min-height: 0;
  overflow-y: auto;
}

.slide-fs-body .quiz,
.slide-fs-body .pr {
  max-width: 1000px;
  margin-left: auto;
  margin-right: auto;
}

.slide-fs-body .quiz {
  margin-top: 0;
}

.slide-fs-slot {
  display: inline-flex;
  align-items: center;
  flex-shrink: 0;
  gap: 12px;
  white-space: nowrap;
}

.slide-fs-head .ch-tabs {
  margin: 0;
  border-bottom: none;
  align-items: center;
}

.slide-fs-head .ch-tab {
  margin-bottom: 0;
  border-radius: 8px;
  padding: 5px 12px;
  border-bottom: 1px solid transparent;
}

.slide-fs-head .ch-tab.on {
  border-bottom-color: var(--s-border);
}

.ch-tabs {
  align-items: flex-end;
}

.ch-expand {
  align-self: center;
  margin-left: auto;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 30px;
  height: 30px;
  background: transparent;
  border: 1px solid var(--s-border);
  border-radius: 8px;
  color: var(--s-muted);
  cursor: pointer;
}

.ch-expand:hover {
  color: var(--s-text);
  border-color: var(--s-accent-a45);
}

.pr-body.single {
  grid-template-columns: minmax(0, 1fr);
}

.fst-slide.ok .fst-slide-num {
  color: var(--s-accent);
  opacity: 1;
}

.fst-slide.bad .fst-slide-num {
  color: var(--s-amber);
  opacity: 1;
}

.slide-fs-toc {
  flex-shrink: 0;
  width: min(400px, 34vw);
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 10px;
  overflow-y: auto;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 14px;
}

.slide-fs-toc-item {
  display: flex;
  align-items: baseline;
  gap: 10px;
  padding: 8px 10px;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--s-muted);
  font-family: "Inter", sans-serif;
  font-size: 13.5px;
  text-align: left;
  cursor: pointer;
  transition:
    background 0.15s,
    color 0.15s;
}

.slide-fs-toc-item:hover {
  color: var(--s-text);
  background: var(--s-panel2);
}

.slide-fs-toc-item.on {
  color: var(--s-accent);
  background: var(--s-green);
  border-color: var(--s-accent-a35);
}

.slide-fs-toc-num {
  flex-shrink: 0;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  opacity: 0.7;
}

.slide-fs-head {
  display: flex;
  align-items: center;
  gap: 16px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  letter-spacing: 1px;
  color: var(--s-muted);
}

.slide-fs-caption {
  flex: 1;
  min-width: 0;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-family: "Inter", sans-serif;
  font-size: 14px;
  font-weight: 600;
  letter-spacing: 0;
  color: var(--s-text);
}

.slide-fs-stage {
  display: flex;
}

.slide-fs-stage .slide {
  width: min(1200px, 100%);
  margin: auto;
  padding: 32px;
  gap: 16px;
}

/* typography scale-up in fullscreen */

.slide-fs .s-rubric {
  font-size: 13px;
}

.slide-fs .s-title {
  font-size: 32px;
}

.slide-fs .s-sub {
  font-size: 17px;
}

.slide-fs .s-body {
  gap: 18px;
  font-size: 18px;
}

.slide-fs .s-topic-big {
  font-size: 26px;
}

.slide-fs .s-node-title {
  font-size: 19px;
}

.slide-fs .s-node-sub {
  font-size: 16px;
}

.slide-fs .s-node-mono {
  font-size: 19px;
}

.slide-fs .s-cmd pre {
  font-size: 17px;
}

.slide-fs .s-main-label {
  font-size: 12px;
}

.slide-fs .s-main-text {
  font-size: 18px;
}

.slide-fs .s-label {
  font-size: 13px;
}

.slide-fs .s-note {
  font-size: 17px;
}

.slide-fs .s-hint {
  font-size: 16px;
}

.slide-fs .s-path {
  font-size: 16px;
}

.slide-fs .s-table {
  font-size: 17px;
}

.slide-fs .s-arr {
  font-size: 22px;
}

.slide-fs .s-topic,
.slide-fs .s-node {
  padding: 16px 18px;
}

.slide-fs .s-node {
  gap: 6px;
}

.slide-fs .s-grid2 {
  gap: 16px;
}

.slide-fs .s-cmd {
  padding: 12px 14px;
}

@media (max-width: 900px) {
  .slide-fs {
    flex-direction: column;
  }

  .slide-fs-toc {
    width: 100%;
    max-height: 200px;
  }
}

@media (max-width: 760px) {
  .slide-fs {
    padding: 14px;
  }
}

/* ── Квиз ─────────────────────────────────────────────── */

.quiz {
  margin-top: 18px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
  padding: 16px 18px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.quiz-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.quiz-head h3 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--s-text);
}

.quiz-lang {
  font-size: 11px;
  color: var(--s-muted);
  white-space: nowrap;
}

.quiz-actions {
  display: flex;
  gap: 8px;
}

.quiz-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 6px 14px;
  border-radius: 8px;
  border: 1px solid var(--s-accent);
  background: var(--s-accent);
  color: var(--s-bg);
  font-size: 12.5px;
  font-weight: 600;
  cursor: pointer;
}

.quiz-btn:hover {
  filter: brightness(1.08);
}

.quiz-btn:disabled {
  opacity: 0.55;
  cursor: default;
}

.quiz-btn.ghost {
  background: transparent;
  color: var(--s-accent);
}

.quiz-result {
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 12.5px;
  line-height: 1.6;
}

.quiz-result p {
  margin: 2px 0;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 12px;
}

.quiz-result.ok {
  background: var(--s-green);
  color: var(--s-text);
}

.quiz-result.fail {
  background: var(--s-amber-bg);
  color: var(--s-text);
}

.quiz-ok-line {
  font-weight: 600;
}

/* Вопросы теоретического квиза */

.quiz-q {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.quiz-q-text {
  margin: 0;
  font-size: 13px;
  line-height: 1.5;
  color: var(--s-text);
}

.quiz-opts {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.quiz-opt {
  text-align: left;
  padding: 8px 12px;
  border-radius: 8px;
  border: 1px solid var(--s-border);
  background: var(--s-bg);
  color: var(--s-text);
  font-size: 12.5px;
  line-height: 1.45;
  cursor: pointer;
}

.quiz-opt:hover:not(:disabled) {
  border-color: var(--s-accent-a45);
}

.quiz-opt.on {
  border-color: var(--s-accent);
  background: var(--s-panel2);
}

.quiz-opt.right {
  border-color: var(--s-accent);
  background: var(--s-green);
}

.quiz-opt.wrong {
  border-color: var(--error);
  color: var(--error);
}

.quiz-opt:disabled {
  cursor: default;
  opacity: 0.92;
}

.quiz-q-expl {
  margin: 0;
  font-size: 11.5px;
  line-height: 1.55;
  color: var(--s-muted);
}

/* Упражнения с вводом ответа */

.ex-row {
  display: flex;
  gap: 8px;
}

.ex-input {
  flex: 1;
  min-width: 0;
  width: 100%;
  box-sizing: border-box;
  background: var(--s-bg);
  color: var(--s-text);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  padding: 6px 12px;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 13px;
  outline: none;
  transition: border-color 0.15s ease;
}

.ex-input:focus {
  border-color: var(--s-accent-a45);
}

.ex-input.right {
  border-color: var(--s-accent);
  color: var(--s-accent);
}

.ex-input.wrong {
  border-color: var(--s-amber);
}

.ex-note {
  margin: 0;
  font-size: 11.5px;
  color: var(--s-amber);
}

.ex-hint-row {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.ex-hint-row .small {
  align-self: flex-start;
  padding: 3px 10px;
  font-size: 11px;
}

.ex-hint {
  margin: 0;
  font-size: 11.5px;
  line-height: 1.55;
  color: var(--s-muted);
}

/* Упражнения с проверкой кода в Docker */

.cx-cm {
  box-sizing: border-box;
  width: 100%;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  overflow: hidden;
}

.cx-cm:focus-within {
  border-color: var(--s-accent-a45);
}

.cx-cm.right {
  border-color: var(--s-accent);
}

.cx-cm .cm-editor {
  min-height: 6.5em;
}

.cx-mark {
  flex-shrink: 0;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.pr-test.ok .cx-mark {
  color: var(--s-accent);
}

.pr-test.bad .cx-mark {
  color: var(--s-amber);
}

.cx-args {
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  color: var(--s-muted);
  margin-right: 8px;
}

.cx-error {
  margin: 0;
  padding: 8px 10px;
  background: var(--s-panel);
  border-left: 3px solid var(--s-amber);
  border-radius: 8px;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 11px;
  line-height: 1.5;
  color: var(--s-amber);
  white-space: pre-wrap;
  word-break: break-word;
}

/* ---------- дашборд на главной ---------- */

.content.home {
  max-width: 1100px;
}

.dash-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 12px;
}

.dash-head h2,
.home h2.dash-sub {
  margin-bottom: 0;
}

.dash-all {
  font-family: "IBM Plex Mono", monospace;
  font-size: 12px;
  color: var(--s-accent);
}

.dash-totals {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
  margin-bottom: 26px;
}

.dash-stat {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 18px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
}

.dash-stat-title {
  font-size: 12px;
  color: var(--s-muted);
}

.dash-stat-num {
  font-size: 28px;
  font-weight: 700;
  line-height: 1.1;
  color: var(--s-text);
}

.dash-stat-num small {
  font-size: 14px;
  font-weight: 500;
  color: var(--s-muted);
}

.dash-stat-hint {
  font-size: 11.5px;
  color: var(--s-muted);
}

.home h2.dash-sub {
  margin: 0 0 12px;
}

.dash-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 12px;
}

.dash-card {
  display: flex;
  flex-direction: column;
  gap: 8px;
  padding: 16px 18px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
}

.dash-card-head {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0;
  margin-bottom: 4px;
  background: transparent;
  border: none;
  color: var(--s-text);
  text-align: left;
  cursor: pointer;
}

.dash-card-head:hover .dash-title {
  color: var(--s-accent);
}

.dash-ico {
  flex-shrink: 0;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 32px;
  height: 32px;
  border: 1px solid var(--s-border);
  border-radius: 8px;
  color: var(--s-accent);
  background: var(--s-bg);
}

.dash-title {
  flex: 1;
  font-size: 14.5px;
  font-weight: 600;
  transition: color 0.15s;
}

.dash-meta {
  font-size: 11px;
  color: var(--s-muted);
  white-space: nowrap;
}

.dash-bar {
  display: grid;
  grid-template-columns: 82px 1fr 54px;
  align-items: center;
  gap: 10px;
  font-size: 11.5px;
  color: var(--s-muted);
}

.dash-bar-num {
  font-family: "IBM Plex Mono", monospace;
  text-align: right;
  color: var(--s-text);
}

.dash-chapters {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  margin-top: 6px;
}

.dash-ch {
  width: 24px;
  height: 24px;
  padding: 0;
  border-radius: 6px;
  border: 1px solid var(--s-border);
  background: var(--s-panel2);
  color: var(--s-muted);
  font-family: "IBM Plex Mono", monospace;
  font-size: 10px;
  cursor: pointer;
  transition:
    border-color 0.15s,
    transform 0.15s;
}

.dash-ch:hover {
  border-color: var(--s-accent);
  transform: translateY(-1px);
}

.dash-ch.l1 {
  background: var(--s-amber-bg);
  border-color: var(--s-amber-a45);
  color: var(--s-amber);
}

.dash-ch.l2 {
  background: var(--s-green);
  border-color: var(--s-accent-a45);
  color: var(--s-accent);
}

.dash-ch.l3 {
  background: var(--s-accent);
  border-color: var(--s-accent);
  color: var(--s-bg);
  font-weight: 700;
}

@media (max-width: 900px) {
  .dash-totals {
    grid-template-columns: 1fr;
  }
}

/* ---------- вход и регистрация ---------- */

.boot {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 100vh;
  color: var(--s-muted);
  background: var(--s-bg);
}

.auth-page {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--s-bg);
}

.auth-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 0.7rem 1.4rem;
  border-bottom: 1px solid var(--s-border);
}

.auth-logo {
  font-size: 1.15rem;
  font-weight: 700;
  letter-spacing: 0.02em;
  color: var(--s-text);
}

.auth-card {
  width: min(420px, calc(100vw - 32px));
  margin: 8vh auto 0;
  padding: 22px 26px 26px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 14px;
}

.auth-tabs {
  display: flex;
  gap: 4px;
  margin-bottom: 18px;
  padding: 4px;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 10px;
}

.auth-tab {
  flex: 1;
  padding: 7px 0;
  border: none;
  border-radius: 7px;
  background: transparent;
  color: var(--s-muted);
  font-size: 13.5px;
  font-weight: 600;
  cursor: pointer;
}

.auth-tab.on {
  background: var(--s-green);
  color: var(--s-accent);
}

.auth-form {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.auth-field {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-size: 12px;
  color: var(--s-muted);
}

.auth-field input {
  box-sizing: border-box;
  width: 100%;
  padding: 9px 12px;
  background: var(--s-bg);
  color: var(--s-text);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  font-family: inherit;
  font-size: 14px;
  outline: none;
  transition: border-color 0.15s;
}

.auth-field input:focus {
  border-color: var(--s-accent-a45);
}

.auth-submit {
  justify-content: center;
  padding: 9px 14px;
  font-size: 14px;
}

.auth-error {
  margin: 0;
  font-size: 12.5px;
  color: var(--s-amber);
}

.auth-quick {
  display: flex;
  flex-direction: column;
  gap: 8px;
  margin-top: 6px;
  padding-top: 14px;
  border-top: 1px dashed var(--s-border);
}

.auth-quick-label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--s-muted);
}

.auth-quick .quiz-btn {
  justify-content: center;
}

.user-chip {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  height: 36px;
  padding: 0 12px 0 6px;
  border: 1px solid var(--s-border);
  border-radius: 8px;
  background: var(--s-bg);
  color: var(--s-text);
  font-size: 13px;
}

.user-ava {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 24px;
  height: 24px;
  border-radius: 6px;
  background: var(--s-green);
  color: var(--s-accent);
  font-size: 12px;
  font-weight: 700;
}

/* история попыток в упражнении */

.pr-hist {
  display: flex;
  flex-direction: column;
  gap: 6px;
  margin-top: 4px;
  padding-top: 12px;
  border-top: 1px dashed var(--s-border);
}

.pr-hist-list {
  list-style: none;
  margin: 0;
  padding: 0;
  max-height: 200px;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  gap: 3px;
}

.pr-hist-item {
  display: grid;
  grid-template-columns: 34px 16px 36px minmax(0, 1fr) auto;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding: 5px 8px;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--s-muted);
  font-size: 11.5px;
  text-align: left;
  cursor: pointer;
}

.pr-hist-item:hover {
  background: var(--s-panel2);
  color: var(--s-text);
}

.pr-hist-item.on {
  border-color: var(--s-accent-a45);
  color: var(--s-text);
}

.pr-hist-item.ok .pr-hist-mark {
  color: var(--s-accent);
}

.pr-hist-item.bad .pr-hist-mark {
  color: var(--s-amber);
}

.pr-hist-n,
.pr-hist-score,
.pr-hist-time {
  font-family: "IBM Plex Mono", monospace;
}

.pr-hist-code {
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

/* ---------- страница настроек ---------- */

.set-page {
  flex: 1;
  padding: 1.6rem 2rem 4rem;
  max-width: 780px;
  width: 100%;
  margin: 0 auto;
  box-sizing: border-box;
}

.set-card {
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
  padding: 22px 26px 8px;
}

.set-card h2 {
  margin: 0 0 4px;
  font-size: 1.35rem;
  color: var(--s-text);
}

.set-sub {
  margin: 0 0 18px;
  font-size: 13px;
  color: var(--s-muted);
}

.set-group {
  margin: 20px 0 0;
  padding-bottom: 8px;
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 1.5px;
  text-transform: uppercase;
  color: var(--s-muted);
  border-bottom: 1px solid var(--s-border);
}

.set-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 24px;
  padding: 16px 0;
  border-bottom: 1px solid var(--s-border);
}

.set-row:last-child {
  border-bottom: none;
}

.set-row-text {
  display: flex;
  flex-direction: column;
  gap: 6px;
  max-width: 560px;
}

.set-row-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--s-text);
}

.set-row-desc {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--s-muted);
}

.set-done {
  color: var(--s-accent);
  font-weight: 600;
}

.set-switch {
  flex-shrink: 0;
  position: relative;
  width: 40px;
  height: 22px;
  padding: 0;
  margin-top: 2px;
  border: 1px solid var(--s-border);
  border-radius: 999px;
  background: var(--s-panel2);
  cursor: pointer;
  transition:
    background 0.2s,
    border-color 0.2s;
}

.set-switch i {
  position: absolute;
  top: 2px;
  left: 2px;
  width: 16px;
  height: 16px;
  border-radius: 50%;
  background: var(--s-muted);
  transition:
    transform 0.2s,
    background 0.2s;
}

.set-switch.on {
  background: var(--s-green);
  border-color: var(--s-accent);
}

.set-switch.on i {
  transform: translateX(18px);
  background: var(--s-accent);
}

/* ---------- вкладки главы и вкладка «Практика» ---------- */

.ch-tabs {
  display: flex;
  gap: 4px;
  margin: 0 0 14px;
  border-bottom: 1px solid var(--s-border);
}

.ch-tab {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 16px;
  margin-bottom: -1px;
  border: 1px solid transparent;
  border-bottom: none;
  border-radius: 10px 10px 0 0;
  color: var(--s-muted);
  font-size: 13.5px;
  font-weight: 600;
  text-decoration: none;
  transition:
    color 0.15s,
    background 0.15s;
}

.ch-tab:hover {
  color: var(--s-text);
}

.ch-tab.on {
  color: var(--s-accent);
  background: var(--s-panel);
  border-color: var(--s-border);
}

.ch-tab-badge {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  font-weight: 500;
  padding: 1px 7px;
  border-radius: 999px;
  background: var(--s-panel2);
  color: var(--s-muted);
}

.ch-tab.on .ch-tab-badge {
  background: var(--s-green);
  color: var(--s-accent);
}

.pr {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.pr-top {
  display: flex;
  align-items: center;
  gap: 12px;
  font-size: 12px;
  color: var(--s-muted);
}

.pr-top-label {
  white-space: nowrap;
}

.pr-bar {
  flex: 1;
  height: 8px;
  border-radius: 999px;
  background: var(--s-panel2);
  border: 1px solid var(--s-border);
  overflow: hidden;
}

.pr-bar i {
  display: block;
  height: 100%;
  background: var(--s-accent);
  border-radius: 999px;
  transition: width 0.4s ease;
}

.pr-body {
  display: grid;
  grid-template-columns: 210px minmax(0, 1fr);
  gap: 14px;
  align-items: start;
}

.pr-list {
  display: flex;
  flex-direction: column;
  gap: 4px;
  padding: 8px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
  position: sticky;
  top: 12px;
  max-height: calc(100vh - 140px);
  overflow-y: auto;
}

.pr-item {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 7px 8px;
  text-align: left;
  background: transparent;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--s-muted);
  font-family: inherit;
  font-size: 12.5px;
  cursor: pointer;
}

.pr-item:hover {
  background: var(--s-panel2);
  color: var(--s-text);
}

.pr-item.on {
  background: var(--s-panel2);
  border-color: var(--s-accent-a45);
  color: var(--s-text);
}

.pr-mark {
  flex-shrink: 0;
  width: 22px;
  height: 22px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: 50%;
  border: 1.5px solid var(--s-border);
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
}

.pr-item.ok .pr-mark {
  background: var(--s-green);
  border-color: var(--s-accent);
  color: var(--s-accent);
}

.pr-item.bad .pr-mark {
  border-color: var(--s-amber);
  color: var(--s-amber);
}

.pr-name {
  line-height: 1.3;
}

.pr-main {
  display: flex;
  flex-direction: column;
  gap: 10px;
  min-width: 0;
  padding: 16px 18px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
}

.pr-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 12px;
}

.pr-head h3 {
  margin: 0;
  font-size: 15px;
  font-weight: 600;
  color: var(--s-text);
}

.pr-badge {
  flex-shrink: 0;
  font-size: 11px;
  padding: 2px 9px;
  border-radius: 999px;
  border: 1px solid var(--s-border);
  color: var(--s-muted);
}

.pr-badge.ok {
  border-color: var(--s-accent);
  color: var(--s-accent);
}

.pr-badge.bad {
  border-color: var(--s-amber);
  color: var(--s-amber);
}

.pr-statement {
  margin: 0;
  font-weight: 400;
  font-size: 13.5px;
  line-height: 1.55;
  color: var(--s-text);
  white-space: pre-wrap;
}

.pr-tests {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.pr-test-head {
  display: flex;
  align-items: baseline;
  gap: 8px;
  font-size: 12px;
  color: var(--s-text);
}

.pr-diff {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 8px;
  margin-top: 6px;
}

.pr-diff pre {
  margin: 4px 0 0;
  padding: 8px 10px;
  max-height: 180px;
  overflow: auto;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--s-text);
  white-space: pre-wrap;
  word-break: break-word;
}

.pr-diff > div:last-child pre {
  border-color: var(--s-amber);
}

.pr-res {
  display: flex;
  flex-direction: column;
  gap: 12px;
  margin-top: 4px;
  padding-top: 12px;
  border-top: 1px dashed var(--s-border);
}

.pr-res-block {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.pr-res-head {
  display: flex;
  align-items: center;
  gap: 10px;
}

.pr-res-sum {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11.5px;
}

.pr-res-sum.ok {
  color: var(--s-accent);
}

.pr-res-sum.bad {
  color: var(--s-amber);
}

.pr-res-time {
  margin-left: auto;
  font-size: 10.5px;
  color: var(--s-muted);
}

.pr-empty {
  margin: 0;
  font-size: 12px;
  color: var(--s-muted);
}

.pr-log {
  margin: 0;
  padding: 8px 10px;
  max-height: 240px;
  overflow: auto;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
  font-family: "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  font-size: 11.5px;
  line-height: 1.5;
  color: var(--s-text);
  white-space: pre-wrap;
  word-break: break-word;
}

/* ширина считается по самой вкладке, а не по окну: слева ещё два меню */
.pr {
  container-type: inline-size;
}

@container (max-width: 640px) {
  .pr-body {
    grid-template-columns: 1fr;
  }

  .pr-list {
    position: static;
    max-height: none;
    flex-direction: row;
    flex-wrap: wrap;
  }
}

/* ---------- анимированные схемы на слайдах (slides/anim/*) ---------- */

.a-stage {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  /* сцена невидима первые кадры и всплывает: прозрачность с задержкой */
  animation: a-rise 0.5s ease 0.35s both;
}

@keyframes a-rise {
  from {
    opacity: 0;
    transform: translateY(10px);
  }
  to {
    opacity: 1;
    transform: none;
  }
}

@keyframes a-fade {
  from {
    opacity: 0;
  }
  to {
    opacity: 1;
  }
}

.a-chips {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px;
}

.a-chip {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1px;
  padding: 5px 12px;
  background: var(--s-panel2);
  border: 1px solid var(--s-border);
  border-radius: 10px;
  color: var(--s-muted);
  font-family: inherit;
  cursor: pointer;
  transition:
    background 0.25s,
    border-color 0.25s,
    color 0.25s,
    transform 0.25s;
}

.a-chip:hover {
  border-color: var(--s-accent-a45);
}

.a-chip.on {
  background: var(--s-green);
  border-color: var(--s-accent);
  color: var(--s-text);
  transform: translateY(-1px);
}

.a-chip-big {
  font-family: "IBM Plex Mono", monospace;
  font-size: 14px;
  color: var(--s-accent);
}

.a-chip-name {
  font-size: 10.5px;
}

.a-svg {
  width: 100%;
  max-width: 520px;
  height: auto;
  /* схема проявляется чуть позже и медленнее остальной сцены */
  animation: a-fade 0.8s ease 0.5s both;
}

.a-ring {
  fill: none;
  stroke-width: 2;
}

.a-ring.a {
  stroke: var(--s-accent);
}

.a-ring.b {
  stroke: var(--s-blue);
}

.a-circle {
  transition: transform 0.9s cubic-bezier(0.3, 0.9, 0.3, 1);
}

.a-circle.a-left {
  transform: translateX(-70px);
}

.a-circle.a-right {
  transform: translateX(70px);
}

.a-circle.joined {
  transform: none;
}

.a-fills {
  opacity: 0;
  transition: opacity 0.4s 0.7s;
}

.a-fills.on {
  opacity: 1;
}

.a-fill {
  opacity: 0;
  transition: opacity 0.5s;
}

.a-fill.on {
  opacity: 0.42;
}

.a-fill.acc {
  fill: var(--s-accent);
}

.a-fill.amb {
  fill: var(--s-amber);
}

.a-fill.blu {
  fill: var(--s-blue);
}

.a-set-label {
  font-family: "IBM Plex Mono", monospace;
  font-size: 15px;
  fill: var(--s-muted);
  transition: transform 0.9s cubic-bezier(0.3, 0.9, 0.3, 1);
}

.a-set-label.a-label-a {
  transform: translateX(-70px);
}

.a-set-label.a-label-b {
  transform: translateX(70px);
}

.a-set-label.joined {
  transform: none;
}

.a-dot {
  transition:
    transform 0.9s cubic-bezier(0.3, 0.9, 0.3, 1),
    opacity 0.6s;
}

.a-dot circle {
  fill: var(--s-panel);
  stroke: var(--s-border);
  stroke-width: 1.5;
  transition:
    stroke 0.4s,
    fill 0.4s,
    r 0.4s;
}

.a-dot text {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  fill: var(--s-text);
}

.a-dot.hit circle {
  stroke: var(--s-accent);
  r: 12.5px;
}

.a-dot.common circle {
  stroke: var(--s-amber);
  fill: var(--s-amber-bg);
}

.a-dot.dim {
  opacity: 0.28;
}

.a-dot.gone {
  opacity: 0;
}

.a-dot.pulse circle {
  animation: a-pulse 0.9s ease both;
}

@keyframes a-pulse {
  0% {
    r: 11px;
  }
  40% {
    r: 17px;
  }
  100% {
    r: 12.5px;
  }
}

.a-result {
  display: flex;
  flex-wrap: wrap;
  align-items: baseline;
  justify-content: center;
  gap: 6px 10px;
  min-height: 22px;
  font-size: 12px;
  color: var(--s-muted);
  animation: slide-in 0.35s ease both;
}

.a-result-expr,
.a-result-set {
  font-family: "IBM Plex Mono", monospace;
  font-size: 14px;
  color: var(--s-accent);
}

.a-result-eq {
  color: var(--s-muted);
}

@media (prefers-reduced-motion: reduce) {
  .a-stage {
    animation-name: a-fade;
  }

  .a-circle,
  .a-fills,
  .a-fill,
  .a-dot,
  .a-dot circle,
  .a-set-label,
  .a-chip,
  .a-result {
    transition: none !important;
    animation: none !important;
  }
}

.a-chip-lbl {
  font-size: 11px;
  white-space: nowrap;
}

/* узлы пошаговых схем: всё, что меняется, меняется плавно */
.a-t,
.a-t * {
  transition:
    transform 0.9s cubic-bezier(0.3, 0.9, 0.3, 1),
    opacity 0.6s,
    fill 0.5s,
    stroke 0.5s,
    fill-opacity 0.5s,
    stroke-opacity 0.5s,
    width 0.7s,
    height 0.7s,
    x 0.7s,
    y 0.7s,
    d 0.9s cubic-bezier(0.3, 0.9, 0.3, 1),
    stroke-dashoffset 1.2s ease;
}

.a-t {
  transform-box: fill-box;
  transform-origin: center;
}

.a-mono {
  font-family: "IBM Plex Mono", monospace;
  fill: var(--s-text);
  font-size: 11px;
}

.a-cap {
  font-size: 9.5px;
  fill: var(--s-muted);
}

.a-hull {
  fill: none;
  stroke: var(--s-accent);
  stroke-width: 1.6;
  stroke-dasharray: 5 4;
  animation: a-march 1.6s linear infinite;
}

@keyframes a-flash {
  0% {
    fill-opacity: 0.08;
  }
  30% {
    fill-opacity: 0.9;
  }
  100% {
    fill-opacity: 0.25;
  }
}

.a-scan {
  fill-opacity: 0.08;
  animation: a-flash 0.6s ease both;
  animation-play-state: paused;
}

@keyframes a-march {
  to {
    stroke-dashoffset: -18;
  }
}

@media (prefers-reduced-motion: reduce) {
  .a-t,
  .a-t * {
    transition: none !important;
    animation: none !important;
  }
}

html {
  scrollbar-gutter: stable;
}

/* ---------- корень раздела: карточки тем ---------- */

.topics-sec {
  margin-bottom: 26px;
}

.topics-title {
  margin-bottom: 10px;
  font-size: 13px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--s-muted);
}

.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(220px, 1fr));
  gap: 10px;
}

.topic-card {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
  padding: 14px 16px;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 12px;
  color: var(--s-text);
  text-align: left;
  cursor: pointer;
  transition:
    border-color 0.15s,
    transform 0.15s;
}

.topic-card:hover {
  border-color: var(--s-accent);
  transform: translateY(-1px);
}

.topic-num {
  font-family: "IBM Plex Mono", monospace;
  font-size: 11px;
  color: var(--s-accent);
}

.topic-name {
  flex: 1;
  font-size: 14px;
  font-weight: 600;
  line-height: 1.35;
}

.topic-meta {
  font-size: 11px;
  color: var(--s-muted);
}

.topic-prog {
  display: grid;
  grid-template-columns: 1fr auto;
  align-items: center;
  gap: 8px;
  width: 100%;
}

.topic-pct {
  font-family: "IBM Plex Mono", monospace;
  font-size: 10.5px;
  color: var(--s-muted);
}

/* ---------- текст озвучки: окно снизу (пока звука нет, абзац «читается» по таймеру) ---------- */

.voice-pop {
  position: fixed;
  bottom: 1rem;
  left: var(--vp-x, 50%);
  transform: translateX(-50%);
  width: min(720px, var(--vp-w, calc(100vw - 2rem)));
  display: flex;
  flex-direction: column;
  gap: 0.35rem;
  align-items: stretch;
  background: var(--s-panel);
  border: 1px solid var(--s-border);
  border-radius: 14px;
  box-shadow: var(--shadow);
  padding: 0.7rem 1.1rem;
  z-index: 1090;
}

.voice-pop-grip {
  position: absolute;
  top: -9px;
  left: 50%;
  width: 64px;
  height: 16px;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--s-border);
  border-radius: 8px;
  background: var(--s-panel);
  cursor: ns-resize;
  touch-action: none;
}

.voice-pop-grip i {
  width: 28px;
  height: 4px;
  border-top: 1.5px solid var(--s-muted);
  border-bottom: 1.5px solid var(--s-muted);
}

.voice-pop-grip:hover,
.voice-pop-grip:hover i {
  border-color: var(--s-accent);
}

.voice-pop-tag {
  flex-shrink: 0;
  font-size: 10.5px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--s-accent);
}

.voice-pop-text {
  margin: 0;
  max-height: 12em;
  overflow-y: auto;
  position: relative;
  font-size: 14px;
  line-height: 1.55;
  color: var(--s-text);
  scrollbar-width: thin;
}

.voice-pop-text .past {
  opacity: 0.55;
}

.voice-pop-text .next {
  opacity: 0.9;
}

.voice-pop-text .now {
  color: var(--s-accent);
  font-weight: 600;
}

/* плеер встаёт над окном текста, а содержимое страниц не прячется под ними */
body:has(.voice-pop) .np-card {
  bottom: calc(1rem + var(--voice-h, 11rem) + 0.6rem);
}

body:has(.voice-pop) .content {
  padding-bottom: calc(var(--voice-h, 11rem) + 2rem);
}

body:has(.voice-pop) .slide-fs {
  padding-bottom: calc(var(--voice-h, 11rem) + 2rem);
}

body:has(.voice-pop):has(.np-card) .slide-fs {
  padding-bottom: calc(var(--voice-h, 11rem) + 9rem);
}

@media (max-width: 768px) {
  .voice-pop {
    bottom: 0.5rem;
  }
}

/* ───── SQL-упражнения: виджет «База данных» (ERD и данные) и сравнение результатов ───── */
.sx {
  margin: 4px 0 10px;
  border: 1px solid var(--s-border);
  border-radius: 10px;
  background: var(--s-panel);
  overflow: hidden;
}

.sx-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  padding: 6px 8px 6px 10px;
}

.sx-fold {
  display: inline-flex;
  align-items: baseline;
  gap: 8px;
  padding: 2px 0;
  border: 0;
  background: transparent;
  color: var(--s-text);
  font-size: 12.5px;
  font-weight: 600;
  cursor: pointer;
}

.sx-fold em {
  font-style: normal;
  font-weight: 400;
  color: var(--s-muted);
  font-size: 11.5px;
}

.sx-chev {
  display: inline-block;
  color: var(--s-muted);
  transition: transform 0.15s;
}

.sx-chev.on {
  transform: rotate(90deg);
}

.sx-seg {
  display: inline-flex;
  border: 1px solid var(--s-border);
  border-radius: 7px;
  overflow: hidden;
}

.sx-seg button {
  padding: 3px 11px;
  border: 0;
  background: transparent;
  color: var(--s-muted);
  font-size: 11.5px;
  font-weight: 600;
  cursor: pointer;
}

.sx-seg button + button {
  border-left: 1px solid var(--s-border);
}

.sx-seg button.on {
  background: var(--s-accent);
  color: var(--s-bg);
}

.sx-erd {
  padding: 4px 10px 8px;
  border-top: 1px solid var(--s-border);
  background: var(--s-bg);
  overflow: auto;
}

.sx-erd svg {
  display: block;
  touch-action: none;
  user-select: none;
}

.sx-tbl {
  cursor: grab;
}

.sx-tbl:active {
  cursor: grabbing;
}

.sx-frame {
  fill: var(--s-panel);
  stroke: var(--s-border);
  stroke-width: 1.2;
}

.sx-head {
  fill: var(--s-panel2);
}

.sx-tbl.on .sx-frame,
.sx-tbl.linked .sx-frame {
  stroke: var(--s-accent);
  stroke-width: 1.6;
}

.sx-tbl.view .sx-frame {
  stroke-dasharray: 4 3;
}

.sx-name {
  fill: var(--s-text);
  font: 700 11.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-count {
  fill: var(--s-muted);
  font: 400 10px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-col {
  fill: var(--s-text);
  font: 400 11px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-type {
  fill: var(--s-muted);
  font: 400 9.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-key {
  font: 700 8.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

g.pk .sx-key {
  fill: var(--s-amber);
}

g.pk .sx-col {
  font-weight: 700;
}

g.fk .sx-key {
  fill: var(--s-blue);
}

.sx-rel path {
  stroke: var(--s-muted);
  stroke-width: 1.3;
  opacity: 0.7;
}

.sx-rel.on path {
  stroke: var(--s-accent);
  stroke-width: 2;
  opacity: 1;
}

.sx-card {
  fill: var(--s-muted);
  font: 700 9.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-rel.on .sx-card {
  fill: var(--s-accent);
}

.sx-erd-foot {
  display: flex;
  justify-content: space-between;
  gap: 10px;
  margin-top: 4px;
  color: var(--s-muted);
  font-size: 11px;
}

.sx-link {
  padding: 0;
  border: 0;
  background: transparent;
  color: var(--s-accent);
  font-size: 11px;
  cursor: pointer;
}

.sx-data {
  border-top: 1px solid var(--s-border);
}

.sx-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 4px;
  padding: 6px 8px 0;
}

.sx-tab {
  padding: 4px 10px;
  border: 1px solid var(--s-border);
  border-bottom: 0;
  border-radius: 7px 7px 0 0;
  background: transparent;
  color: var(--s-muted);
  font: 600 11.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
  cursor: pointer;
}

.sx-tab em {
  margin-left: 6px;
  font-style: normal;
  font-weight: 400;
  font-size: 10px;
  opacity: 0.8;
}

.sx-tab.on {
  background: var(--s-bg);
  color: var(--s-text);
}

.sx-scroll {
  max-height: 260px;
  overflow: auto;
  background: var(--s-bg);
  border-top: 1px solid var(--s-border);
}

.sx-grid {
  width: 100%;
  border-collapse: collapse;
  font: 400 11.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sx-grid th {
  position: sticky;
  top: 0;
  padding: 5px 10px;
  text-align: left;
  white-space: nowrap;
  background: var(--s-panel2);
  color: var(--s-text);
  border-bottom: 1px solid var(--s-border);
}

.sx-grid th b {
  margin-right: 5px;
  font-size: 8.5px;
  color: var(--s-amber);
}

.sx-grid th.fk b {
  color: var(--s-blue);
}

.sx-grid th small {
  margin-left: 6px;
  font-weight: 400;
  font-size: 9.5px;
  color: var(--s-muted);
}

.sx-grid td {
  padding: 3px 10px;
  white-space: nowrap;
  border-bottom: 1px solid var(--s-border);
  color: var(--s-text);
}

.sx-grid tr:last-child td {
  border-bottom: 0;
}

.sx-num {
  display: block;
  text-align: right;
}

.sx-null {
  color: var(--s-muted);
  font-size: 10.5px;
}

.sx-empty {
  color: var(--s-muted);
  text-align: center;
}

.sx-more {
  margin: 0;
  padding: 4px 10px 6px;
  color: var(--s-muted);
  font-size: 11px;
  background: var(--s-bg);
}

/* сравнение результата с эталоном */
.sd {
  margin-top: 6px;
}

.sd-sum {
  margin: 0 0 6px;
  color: var(--s-amber);
  font-size: 12px;
}

.sd-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 10px;
}

@media (max-width: 900px) {
  .sd-grid {
    grid-template-columns: 1fr;
  }
}

.sd-title {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  margin-bottom: 4px;
}

.sd-count {
  color: var(--s-muted);
  font-size: 11px;
}

.sd-side.exp .sd-scroll {
  border-color: var(--s-accent-a45);
}

.sd-scroll {
  max-height: 260px;
  overflow: auto;
  background: var(--s-bg);
  border: 1px solid var(--s-border);
  border-radius: 8px;
}

.sd-t {
  width: 100%;
  border-collapse: collapse;
  font: 400 11.5px "SF Mono", "JetBrains Mono", Menlo, Consolas, monospace;
}

.sd-t th,
.sd-t td {
  padding: 3px 9px;
  white-space: nowrap;
  text-align: left;
  border-bottom: 1px solid var(--s-border);
  color: var(--s-text);
}

.sd-t th {
  position: sticky;
  top: 0;
  background: var(--s-panel2);
}

.sd-t .num {
  text-align: right;
}

.sd-t .sd-n {
  width: 1%;
  color: var(--s-muted);
  font-size: 10px;
  text-align: right;
}

.sd-t tr:last-child td {
  border-bottom: 0;
}

.sd-t td.extra,
.sd-t th.extra {
  background: color-mix(in srgb, var(--s-red) 24%, transparent);
  color: var(--s-red);
  font-weight: 700;
}

.sd-t td.missing,
.sd-t th.missing {
  background: color-mix(in srgb, var(--s-amber) 26%, transparent);
  color: var(--s-amber);
  font-weight: 700;
}

.sd-t tr.sd-extra td:first-child {
  box-shadow: inset 3px 0 0 var(--s-red);
}

.sd-t tr.sd-missing td:first-child {
  box-shadow: inset 3px 0 0 var(--s-amber);
}

.sd-empty {
  color: var(--s-muted);
  text-align: center;
}

.sd-more {
  margin: 3px 0 0;
  color: var(--s-muted);
  font-size: 11px;
}

.sd-legend {
  margin: 8px 0 0;
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 4px 14px;
  color: var(--s-muted);
  font-size: 11.5px;
}

.sd-key {
  display: inline-block;
  width: 10px;
  height: 10px;
  margin-right: 5px;
  border-radius: 3px;
  vertical-align: -1px;
}

.sd-key.extra {
  background: var(--s-red);
}

.sd-key.missing {
  background: var(--s-amber);
}

.sd-note {
  flex-basis: 100%;
}