@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:wght@400;500;600;700;800&family=JetBrains+Mono:wght@500;700&display=swap');

/* ==========================================================================
   1. ДИЗАЙН-ТОКЕНЫ И ПЕРЕМЕННЫЕ (DARK MODE BY DEFAULT)
   ========================================================================== */
:root {
  color-scheme: dark;

  --bg-app: #030508;
  --bg-surface: #0b101b;
  --bg-surface-deep: #010204;
  --bg-elevated-hover: #131d31;
  --bg-elevated-hover-2: #1e293b;
  --bg-overlay: rgba(0, 0, 0, 0.75);
  --sidebar-bg: #030508;
  --bg-pill: rgba(255, 255, 255, 0.05);

  --border-default: #1e2c4d;
  --border-subtle: #0b101b;
  --border-strong: #2563eb;

  --text-heading: #f8fafc;
  --text-body: #cbd5e1;
  --text-muted: #8ea0bd;
  --text-faint: #f8fafc;
  --text-disabled: #475569;

  --accent: #34d399;
  --accent-hover: #6ee7b7;
  --accent-soft: #a7f3d0;
  --accent-strong: #10b981;
  --accent-bg-deep: #052e16;
  --accent-text: #dcfce7;

  --accent-2: #38bdf8;
  --accent-2-soft: #7dd3fc;
  --gradient-brand: linear-gradient(135deg, var(--accent) 0%, var(--accent-2) 100%);
  --shadow-glow: 0 0 22px rgba(52, 211, 153, 0.18);
  --shadow-soft: 0 6px 20px rgba(0, 0, 0, 0.25);

  --success: #34d399;
  --warning: #fbbf24;
  --danger: #fb7185;

  --radius-sm: 8px;
  --radius-md: 10px;
  --radius-lg: 14px;
}

/* ==========================================================================
   2. СВЕТЛАЯ ТЕМА (LIGHT MODE)
   ========================================================================== */
body.light-theme {
  color-scheme: light;

  --bg-app: #f6f7fb;
  --bg-surface: #ffffff;
  --bg-surface-deep: #eef1f6;
  --bg-elevated-hover: #f4f6fa;
  --bg-elevated-hover-2: #e8ecf3;
  --sidebar-bg: #ffffff;
  --bg-pill: #eef1f7;

  --border-default: #e2e6ee;
  --border-subtle: #edf0f5;
  --border-strong: #b7c0d1;

  --text-heading: #0f172a;
  --text-body: #334155;
  --text-muted: #64748b;
  --text-faint: #0f172a;
  --text-disabled: #94a3b8;

  --shadow-glow: 0 4px 16px rgba(15, 23, 42, 0.06);
  --shadow-soft: 0 4px 16px rgba(15, 23, 42, 0.06);
}

/* ==========================================================================
   3. ГЛОБАЛЬНЫЕ СТИЛИ И ТИПОГРАФИКА
   ========================================================================== */
*:not(#desmos-calculator-container *),
*::before:not(#desmos-calculator-container *),
*::after:not(#desmos-calculator-container *) {
  box-sizing: border-box;
}

body, p, span, label, div, td, th, input, select, textarea,
button:not([class*="dcg-"]):not(#desmos-calculator-container *) {
  font-family: 'Plus Jakarta Sans', sans-serif !important;
  letter-spacing: -0.005em;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.font-mono, .am-card .font-mono, [class*="font-mono"] {
  font-family: 'JetBrains Mono', monospace !important;
  letter-spacing: normal;
}

body {
  margin: 0;
  padding: 0;
  background-color: var(--bg-app);
  color: var(--text-body);
  font-size: 13px;
  transition: background-color 0.35s ease, color 0.35s ease;
}

.hidden {
  display: none !important;
}

.logo-img {
  max-width: 65px;
  max-height: 65px;
  object-fit: contain;
}

/* ==========================================================================
   4. КОМПАКТНЫЙ САЙДБАР И ХЕДЕР
   ========================================================================== */
aside, .sidebar, nav.sidebar, [class*="sidebar"] {
  width: 170px !important;
  min-width: 170px !important;
  padding: 10px !important;
  background-color: var(--sidebar-bg) !important;
}

body.light-theme aside,
body.light-theme .sidebar,
body.light-theme nav.sidebar {
  border-right: 1px solid var(--border-default);
}

aside a, .sidebar a, nav.sidebar a,
aside button, .sidebar button, nav.sidebar button {
  font-size: 12px !important;
  padding: 6px 10px !important;
}

button:not([class*="dcg-"]):not(#desmos-calculator-container *) {
  border-radius: var(--radius-md) !important;
  transition: all 0.2s ease !important;
  font-size: 12px !important;
  padding: 6px 12px !important;
}

.rounded-xl, .rounded-2xl { border-radius: var(--radius-lg) !important; }
.rounded-lg { border-radius: var(--radius-md) !important; }

#app-screen header *,
.bg-slate-800.rounded-xl.border.border-slate-700.px-6.py-5 span,
.bg-slate-800.rounded-xl.border.border-slate-700.px-6.py-5 div,
.bg-slate-800.rounded-xl.border.border-slate-700.px-6.py-5 h2 {
  color: var(--text-heading) !important;
}

#user-welcome {
  color: var(--text-heading) !important;
  font-size: 18px !important;
}

.bg-slate-900\/90 {
  background-color: var(--bg-pill) !important;
  border-color: var(--border-default) !important;
  color: var(--text-body) !important;
  padding: 4px 10px !important;
  font-size: 12px !important;
}

.bg-slate-900\/90 *,
.bg-slate-900\/90 span { color: var(--text-body) !important; }

.bg-slate-900\/90 .font-bold,
.bg-slate-900\/90 span.font-bold,
.bg-slate-900\/90 span[id^="user-"] {
  color: var(--text-heading) !important;
}

/* ==========================================================================
   5. ДВУХКОЛОНОЧНАЯ СЕТКА И КАРТОЧКИ PRACTICE
   ========================================================================== */
.practice-container,
main .grid,
#practice-screen,
.practice-workspace {
  display: flex !important;
  gap: 16px !important;
  width: 100% !important;
  max-width: 1280px !important;
  margin: 0 auto !important;
  align-items: stretch !important;
  position: relative !important;
}

.question-container,
.question-card,
#question-box,
main .flex-1 {
  flex: 1 !important;
  min-width: 0 !important;
  max-width: 800px !important;
  display: flex !important;
  flex-direction: column !important;
  justify-content: space-between !important;
}

/* Контейнеры картинок в вопросах и объяснениях */
.question-container img,
.question-card img,
#question-box img,
#practice-main-content img,
#explanation-box img {
  max-height: 220px !important;
  width: auto !important;
  object-fit: contain !important;
  border-radius: var(--radius-md) !important;
  border: 1px solid var(--border-default) !important;
  background-color: var(--bg-surface-deep) !important;
  padding: 8px !important;
}

.answer-option,
[class*="answer-btn"],
.answers-grid button {
  padding: 8px 12px !important;
  font-size: 12px !important;
}

/* ==========================================================================
   6. TAILWIND ОВЕРРАЙДЫ И ИСПРАВЛЕНИЕ ТЕМНЫХ/СВЕТЛЫХ БЛОКОВ
   ========================================================================== */
.bg-slate-900:not(#desmos-calculator-container *) { background-color: var(--bg-app) !important; }
.bg-slate-800:not(#desmos-calculator-container *) { background-color: var(--bg-surface) !important; }
.bg-slate-950:not(#desmos-calculator-container *) { background-color: var(--bg-surface-deep) !important; }
.bg-slate-700:not(#desmos-calculator-container *) { background-color: var(--bg-elevated-hover) !important; }
.bg-slate-800\/80:not(#desmos-calculator-container *) { background-color: color-mix(in srgb, var(--bg-surface) 80%, transparent) !important; }

.bg-white:not(#desmos-calculator-container *) {
  background-color: var(--bg-surface) !important;
}

.hover\:bg-slate-600:hover:not(#desmos-calculator-container *) { background-color: var(--bg-elevated-hover-2) !important; }
.hover\:bg-slate-700:hover:not(#desmos-calculator-container *) { background-color: var(--bg-elevated-hover) !important; }
.hover\:bg-slate-800:hover:not(#desmos-calculator-container *) { background-color: var(--bg-surface) !important; }

.border-slate-700:not(#desmos-calculator-container *),
.border-slate-200:not(#desmos-calculator-container *) { border-color: var(--border-default) !important; }
.border-slate-800:not(#desmos-calculator-container *) { border-color: var(--border-subtle) !important; }
.border-slate-600:not(#desmos-calculator-container *) { border-color: var(--border-strong) !important; }

.text-white:not(#desmos-calculator-container *)     { color: var(--text-heading) !important; }
.text-slate-200:not(#desmos-calculator-container *) { color: var(--text-heading) !important; }
.text-slate-300:not(#desmos-calculator-container *) { color: var(--text-body) !important; }
.text-slate-400:not(#desmos-calculator-container *) { color: var(--text-body) !important; }
.text-slate-600:not(#desmos-calculator-container *) { color: var(--text-muted) !important; }
.text-slate-700:not(#desmos-calculator-container *),
.text-slate-800:not(#desmos-calculator-container *),
.text-slate-900:not(#desmos-calculator-container *) { color: var(--text-heading) !important; }

.text-indigo-400:not(#desmos-calculator-container *),
.text-indigo-500:not(#desmos-calculator-container *),
.text-indigo-600:not(#desmos-calculator-container *) { color: var(--accent) !important; }
.bg-indigo-600:not(#desmos-calculator-container *)   { background-color: var(--accent) !important; color: #06281c !important; }

/* ==========================================================================
   7. КАСТОМНЫЕ AM-* КОМПОНЕНТЫ
   ========================================================================== */
.am-card {
  background-color: var(--bg-surface);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-lg);
  transition: all 0.25s ease;
  padding: 12px !important;
}

.am-card:hover {
  border-color: var(--accent) !important;
  box-shadow: var(--shadow-glow);
  transform: translateY(-1px);
}

.am-gradient-text {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
}

.am-badge {
  display: inline-flex;
  align-items: center;
  gap: .35rem;
  font-weight: 600;
  border-radius: var(--radius-sm);
  padding: 0.3rem 0.6rem;
  font-size: 0.75rem !important;
  letter-spacing: 0.02em;
}

.am-badge-accent {
  background-color: rgba(52, 211, 153, 0.12);
  color: var(--accent);
  border: 1px solid rgba(52, 211, 153, 0.25);
}

.bg-slate-800.rounded-xl,
.bg-slate-800.rounded-2xl,
.bg-slate-800\/80.rounded-2xl {
  box-shadow: var(--shadow-soft);
}

/* ==========================================================================
   8. ПЕРЕКЛЮЧАТЕЛЬ ТЕМЫ
   ========================================================================== */
.theme-toggle-btn {
  position: relative;
  width: 34px;
  height: 34px;
  border-radius: var(--radius-sm);
  background-color: var(--bg-pill);
  border: 1px solid var(--border-default);
  color: var(--text-body);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all 0.2s ease;
  outline: none;
}

.theme-toggle-btn:hover {
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

.theme-toggle-btn svg {
  width: 16px;
  height: 16px;
  position: absolute;
  transition: transform 0.5s cubic-bezier(0.4, 0, 0.2, 1), opacity 0.3s ease;
}

body:not(.light-theme) .sun-icon { transform: rotate(90deg) scale(0); opacity: 0; }
body:not(.light-theme) .moon-icon { transform: rotate(0deg) scale(1); opacity: 1; color: var(--accent); }

body.light-theme .sun-icon { transform: rotate(0deg) scale(1); opacity: 1; color: #f2a93b; }
body.light-theme .moon-icon { transform: rotate(-90deg) scale(0); opacity: 0; }

/* ==========================================================================
   9. ТАБЛИЦЫ
   ========================================================================== */
table {
  border-collapse: separate !important;
  border-spacing: 0 !important;
}

table thead th {
  font-size: 0.7rem !important;
  font-weight: 600 !important;
  letter-spacing: 0.06em;
  color: var(--text-muted) !important;
  background-color: color-mix(in srgb, var(--bg-app) 60%, transparent);
  border-bottom: 1px solid var(--border-default) !important;
  padding: 6px 10px !important;
}

table tbody tr {
  transition: background-color 0.15s ease;
}

table tbody tr:not(:last-child) td {
  border-bottom: 1px solid var(--border-subtle) !important;
}

table tbody tr:hover td {
  background-color: var(--bg-elevated-hover) !important;
}

table td, table th {
  font-size: 0.85rem !important;
  padding: 6px 10px !important;
}

.overflow-x-auto table {
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-md);
  overflow: hidden;
}

table td span[class*="rounded"] {
  border-radius: 999px !important;
  font-weight: 600 !important;
  letter-spacing: 0.01em;
}

/* ==========================================================================
   10. EXPLANATION DRAWER (ПОЯСНЕНИЯ К ВОПРОСАМ)
   ========================================================================== */
#explanation-box {
  background-color: var(--bg-surface) !important;
  border-color: var(--border-default) !important;
  box-shadow: var(--shadow-soft) !important;
}

#explanation-box h2,
#explanation-box p,
#explanation-box span,
#explanation-box div {
  color: var(--text-heading) !important;
}

.am-explanation-box,
[id*="explanation-container"],
[id*="explanation-text"],
#explanation-box .overflow-y-auto > div {
  background-color: var(--bg-surface-deep) !important;
  border: 1px solid var(--border-default) !important;
  color: var(--text-heading) !important;
  padding: 1rem !important;
  border-radius: var(--radius-md) !important;
  word-break: break-word !important;
  overflow-wrap: anywhere !important;
  white-space: pre-wrap !important;
}

#explanation-box button {
  background-color: var(--bg-pill) !important;
  color: var(--text-heading) !important;
  border: 1px solid var(--border-default) !important;
}

#explanation-box button:hover {
  background-color: var(--bg-elevated-hover) !important;
  border-color: var(--accent) !important;
}

/* ==========================================================================
   11. ГЛОБАЛЬНЫЕ ФИКСЫ КНОПОК И ТАЙМЕРА (ИСКЛЮЧАЯ DESMOS)
   ========================================================================== */
body:not(.light-theme) [id*="timer"],
body:not(.light-theme) button:not([class*="dcg-"]):not(#desmos-calculator-container *),
body:not(.light-theme) .bg-white:not(#desmos-calculator-container *),
body:not(.light-theme) .bg-slate-100:not(#desmos-calculator-container *) {
  background-color: var(--bg-surface-deep) !important;
  color: var(--text-heading) !important;
  border: 1px solid var(--border-default) !important;
}

body:not(.light-theme) [id*="timer"] *,
body:not(.light-theme) button:not([class*="dcg-"]):not(#desmos-calculator-container *) * {
  color: var(--text-heading) !important;
}

body:not(.light-theme) button.bg-emerald-500:not(#desmos-calculator-container *),
body:not(.light-theme) button[class*="emerald"]:not(#desmos-calculator-container *) {
  background-color: var(--accent) !important;
  color: #06281c !important;
  border: none !important;
}

/* ==========================================================================
   12. ПОЛНАЯ ИЗОЛЯЦИЯ DESMOS ОТ САЙТА
   ========================================================================== */
#desmos-calculator-container {
  all: initial;
  display: block;
  width: 100%;
  height: 100%;
  position: relative;
}
/* ==========================================================================
   13. МАТЕМАТИЧЕСКАЯ РАЗМЕТКА (корень / дробь / степень / умножение / градус)
   Толщина линий корня и дроби увеличена намеренно — просили "не тонко".
   ========================================================================== */
.am-sqrt {
  display: inline-flex;
  align-items: stretch; /* оба потомка (галочка и содержимое) растягиваются
                            на одинаковую высоту — поэтому SVG-галочка ниже
                            всегда идеально достаёт до верхней черты, какая
                            бы ни была высота содержимого */
  vertical-align: middle;
}
.am-sqrt-tick {
  width: 0.5em;
  margin-right: -1px;
  flex-shrink: 0;
  display: block;
}
.am-sqrt-tick svg {
  width: 100%;
  height: 100%;
  display: block;
  overflow: visible;
}
/* Раньше уголок корня был прямым (просто вертикальная палочка + черта) —
   это не похоже на настоящий знак корня, у которого должна быть галочка,
   ныряющая вниз перед подъёмом к черте. SVG-путь ниже рисует именно такую
   форму: от середины высоты вниз к нижней точке, затем вверх-вправо к
   черте — как в обычном математическом наборе. */
.am-sqrt-content {
  display: inline-block;
  border-top: 2.5px solid currentColor;
  padding: 1px 4px 1px 3px;
  font-weight: 600;
}

.am-frac {
  display: inline-flex;
  flex-direction: column;
  align-items: center;
  vertical-align: middle;
  margin: 0 0.25em;
  line-height: 1.25;
  font-size: 0.92em;
}
.am-frac-num, .am-frac-den {
  padding: 0 4px;
  font-weight: 600;
  text-align: center;
  white-space: nowrap;
}
.am-frac-bar {
  width: 100%;
  height: 0;
  border-top: 2.5px solid currentColor;
  margin: 2px 0;
}

.am-sup {
  font-weight: 700;
}
.am-deg {
  font-weight: 700;
}
.am-times {
  font-weight: 700;
}
.am-pi {
  font-weight: 700;
  font-style: italic;
}

/* Маленькая цифра степени корня (cbrt/root) — сидит слева-сверху от галочки */
.am-root-index {
  align-self: flex-start;
  font-size: 0.55em;
  font-weight: 800;
  line-height: 1;
  margin-right: -0.15em;
  margin-top: -0.1em;
}