/* roulang page: index */
:root {
      --color-brand-deep: #132a24;
      --color-brand-darker: #0b1a16;
      --color-brand-gold: #c8a165;
      --color-brand-amber: #d4af37;
      --color-bg-stone: #fcfbf9;
      --color-bg-card: #f5f4ef;
      --color-text-charcoal: #232725;
      --color-text-muted: #6b726d;
    }
    * {
      box-sizing: border-box;
      scroll-behavior: smooth;
    }
    body {
      background-color: var(--color-bg-stone);
      color: var(--color-text-charcoal);
      font-family: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
      overflow-x: hidden;
    }
    .academic-title {
      font-family: "Noto Serif SC", "Songti SC", "STSong", serif;
      letter-spacing: -0.025em;
    }
    .hero-glow {
      box-shadow: 0 0 35px rgba(200, 161, 101, 0.25);
    }
    .card-border {
      border: 1px solid rgba(19, 42, 36, 0.08);
      transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    }
    .card-border:hover {
      border-color: rgba(200, 161, 101, 0.45);
      transform: translateY(-4px);
      box-shadow: 0 16px 32px rgba(11, 26, 22, 0.08);
    }
    .gold-gradient-text {
      background: linear-gradient(135deg, #d4af37 0%, #c8a165 50%, #f6e6b4 100%);
      -webkit-background-clip: text;
      -webkit-text-fill-color: transparent;
    }
    .sticky-bottom-bar {
      transition: transform 0.35s ease-in-out, opacity 0.35s ease-in-out;
    }
    .sticky-bottom-bar.hidden-bar {
      transform: translateY(120%);
      opacity: 0;
      pointer-events: none;
    }