/* === 深色主题统一设计 === */
/* @author Echo009 | @since 2026-05-25 */

@import url('https://fonts.googleapis.com/css2?family=Libre+Baskerville:ital,wght@0,400;0,700;1,400&family=Noto+Serif+SC:wght@400;700;900&display=swap');

:root {
  /* 背景层级 */
  --bg-deep: #0b0d17;
  --bg-page: #151929;
  --bg-surface: #1c2038;
  --bg-elevated: #232848;
  --bg-input: #111425;

  /* 文字层级 */
  --ink: #c9d1d9;
  --ink-bright: #e8e0d0;
  --ink-muted: #6b7a8d;
  --ink-dim: #3a4455;

  /* 强调色 */
  --accent: #5b8def;
  --accent-hover: #4a7de0;
  --accent-soft: rgba(91,141,239,0.12);
  --gold: #c9a84c;
  --gold-soft: rgba(201,168,76,0.12);
  --violet: #8b7ec8;
  --violet-soft: rgba(139,126,200,0.10);
  --teal: #4db6ac;
  --teal-soft: rgba(77,182,172,0.10);

  /* 语义色 */
  --success: #4db6ac;
  --success-soft: rgba(77,182,172,0.12);
  --error: #e55b6f;
  --error-soft: rgba(229,91,111,0.12);
  --warning: #d9a84c;
  --warning-soft: rgba(217,168,76,0.12);

  /* 功能 */
  --radius: 12px;
  --radius-sm: 8px;
  --border: rgba(255,255,255,0.06);
  --border-hover: rgba(255,255,255,0.10);
  --shadow: 0 4px 24px rgba(0,0,0,0.3);
  --shadow-hover: 0 12px 48px rgba(0,0,0,0.4);
  --transition: 0.3s ease;

  /* 字体 */
  --font-heading: 'Libre Baskerville', 'Noto Serif SC', 'Songti SC', Georgia, serif;
  --font-body: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  --font-code: Consolas, "Courier New", monospace;
}

/* === 页面背景 === */
body.page-catalog { background: var(--bg-deep); }
body.page-exam,
body.page-teacher { background: var(--bg-page); }

/* === 背景装饰层 === */
.bg-layer {
  position: fixed; inset: 0; z-index: 0; pointer-events: none;
  overflow: hidden;
}
.bg-layer::before {
  content: '';
  position: absolute;
  width: 140%; height: 140%;
  top: -20%; left: -20%;
  background:
    radial-gradient(ellipse 600px 500px at 25% 15%, rgba(139,126,200,0.07) 0%, transparent 70%),
    radial-gradient(ellipse 500px 600px at 75% 80%, rgba(77,182,172,0.05) 0%, transparent 70%),
    radial-gradient(ellipse 400px 400px at 60% 30%, rgba(201,168,76,0.04) 0%, transparent 70%);
  animation: drift 40s ease-in-out infinite alternate;
}
@keyframes drift {
  0%  { transform: translate(0, 0) rotate(0deg); }
  100%{ transform: translate(-30px, 20px) rotate(1.5deg); }
}
.bg-layer::after {
  content: '';
  position: absolute; inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)' opacity='0.03'/%3E%3C/svg%3E");
  background-size: 200px 200px;
  opacity: 0.5;
}

/* === 通用组件 === */
/* 注意：.card 的 base 样式定义在 theme.css 中，各页面特有 CSS 可覆盖 */
.card {
  background: linear-gradient(170deg, rgba(28,32,56,0.85), rgba(20,22,44,0.95));
  border: 1px solid var(--border);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  padding: 24px;
}
/* 目录页 .card 是链接元素，需要更大 padding 和圆角 */
.page-catalog .card { padding: 36px 30px 30px; border-radius: 16px; }

.btn {
  border: none;
  border-radius: var(--radius-sm);
  padding: 10px 18px;
  font-size: 0.95rem;
  cursor: pointer;
  transition: all var(--transition);
}
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent-hover); }
.btn-success { background: var(--success); color: #0b0d17; font-weight: 600; }
.btn-success:hover { opacity: 0.9; }
.btn-secondary {
  background: rgba(255,255,255,0.06);
  color: var(--ink);
  border: 1px solid var(--border);
}
.btn-secondary:hover { background: rgba(255,255,255,0.10); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

input[type="text"],
select,
textarea {
  background: var(--bg-input);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  color: var(--ink);
  padding: 10px 12px;
  font-size: 1rem;
  transition: border-color var(--transition);
}
input:focus, select:focus {
  border-color: var(--accent);
  outline: none;
}

.progress-bar-track {
  background: rgba(255,255,255,0.06);
  border-radius: 999px;
  overflow: hidden;
}
.progress-bar-fill {
  background: linear-gradient(90deg, var(--accent), var(--accent-hover));
  border-radius: 999px;
  transition: width 0.35s ease;
}

/* hint text colors for upload feedback */
.hint-ok { color: var(--success) !important; }
.hint-warn { color: var(--warning) !important; }

/* === Custom Modal === */
.modal-overlay {
  position: fixed; inset: 0; z-index: 9999;
  background: rgba(0,0,0,0.55);
  display: flex; align-items: center; justify-content: center;
  opacity: 0; visibility: hidden;
  transition: opacity 0.25s ease, visibility 0.25s ease;
}
.modal-overlay.active { opacity: 1; visibility: visible; }

.modal-card {
  background: linear-gradient(170deg, var(--bg-surface), var(--bg-page));
  border: 1px solid var(--border-hover);
  border-radius: var(--radius);
  box-shadow: 0 16px 64px rgba(0,0,0,0.5);
  padding: 28px 32px 24px;
  max-width: 420px; width: 90%;
  transform: translateY(12px) scale(0.97);
  transition: transform 0.25s ease;
}
.modal-overlay.active .modal-card { transform: translateY(0) scale(1); }

.modal-icon {
  font-size: 1.6rem; margin-bottom: 12px; display: block;
}
.modal-card.type-warn .modal-icon { color: var(--warning); }
.modal-card.type-confirm .modal-icon { color: var(--accent); }
.modal-card.type-error .modal-icon { color: var(--error); }

.modal-body {
  color: var(--ink); font-size: 0.95rem; line-height: 1.7;
  margin-bottom: 24px;
}

.modal-actions {
  display: flex; justify-content: flex-end; gap: 10px;
}
.modal-actions .btn { min-width: 80px; text-align: center; }

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0s !important;
    transition-duration: 0s !important;
  }
}