* { margin: 0; padding: 0; box-sizing: border-box; }

    :root {
      --bg-top: #f0fdf4;
      --bg-bottom: #ecfeff;
      --surface: rgba(255, 255, 255, 0.82);
      --surface-border: rgba(255, 255, 255, 0.9);
      --text-primary: #1e3a2f;
      --text-secondary: #5b7a6b;
      --accent: #34d399;
      --radius-lg: 24px;
      --radius-pill: 999px;
      --mask-bg: #080808;
    }

    body {
      min-height: 100vh;
      font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
      color: var(--text-primary);
      background: linear-gradient(165deg, var(--bg-top) 0%, #f7fee7 45%, var(--bg-bottom) 100%);
    }

    .page { max-width: 960px; margin: 0 auto; padding: 28px 20px 64px; }

    .top-bar {
      display: flex; justify-content: space-between; align-items: center;
      margin-bottom: 28px;
    }
    .back-link {
      padding: 10px 18px; font-size: 14px; color: var(--text-secondary);
      text-decoration: none; background: var(--surface);
      border: 1px solid var(--surface-border); border-radius: var(--radius-pill);
    }

    .intro { text-align: center; margin-bottom: 32px; }
    .intro h1 {
      font-size: clamp(28px, 5vw, 38px); font-weight: 700; margin-bottom: 10px;
      background: linear-gradient(135deg, #065f46, #0d9488, #0891b2);
      -webkit-background-clip: text; -webkit-text-fill-color: transparent;
    }
    .intro p { font-size: 15px; line-height: 1.65; color: var(--text-secondary); max-width: 600px; margin: 0 auto; }

    .tab-bar {
      display: flex; flex-wrap: wrap; gap: 8px; padding: 8px; margin-bottom: 24px;
      background: var(--surface); border: 1px solid var(--surface-border);
      border-radius: var(--radius-lg);
    }
    .tab-btn {
      flex: 1 1 100px; padding: 11px 12px; font-size: 13px;
      border: none; border-radius: 16px; cursor: pointer;
      background: transparent; color: var(--text-secondary);
    }
    .tab-btn.active { background: #fff; color: #065f46; box-shadow: 0 4px 14px rgba(16,185,129,.15); }

    .tab-panel { display: none; }
    .tab-panel.active { display: block; }

    .panel-card {
      background: var(--surface); border: 1px solid var(--surface-border);
      border-radius: var(--radius-lg); overflow: hidden;
    }
    .panel-header { padding: 22px 26px 0; }
    .panel-header h2 { font-size: 19px; margin-bottom: 8px; }
    .panel-header p { font-size: 14px; line-height: 1.65; color: var(--text-secondary); }
    .panel-header .ref { font-size: 12px; color: #94a3b8; margin-top: 6px; }

    .preview-area {
      margin: 22px auto 26px;
      width: 100%; max-width: 360px;
      aspect-ratio: 592 / 800;
      border-radius: 12px;
      position: relative;
      overflow: hidden;
      background: var(--mask-bg);
      box-shadow: 0 12px 36px rgba(0,0,0,.18);
    }

    .panel-actions { padding: 0 26px 26px; }
    .action-btn {
      padding: 11px 22px; font-size: 14px; font-weight: 600; color: #fff;
      border: none; border-radius: var(--radius-pill); cursor: pointer;
      background: linear-gradient(135deg, var(--accent), #2dd4bf);
    }

    .footer-hint { margin-top: 32px; text-align: center; font-size: 13px; color: var(--text-secondary); }

    .stage { position: absolute; inset: 0; overflow: hidden; }

    .scene-fill {
      position: absolute; inset: 0;
      background-color: var(--scene-color, #38bdf8);
      background-image: var(--scene-image, none);
      background-size: cover;
      background-position: center;
    }

    .scene-tag {
      position: absolute; left: 50%; top: 50%;
      transform: translate(-50%, -50%);
      font-size: 13px; font-weight: 600; letter-spacing: .16em;
      color: rgba(255,255,255,.9); text-shadow: 0 1px 6px rgba(0,0,0,.25);
      pointer-events: none; z-index: 9;
    }

    /* 1. 竖形百叶窗：黑底 + 竖条从左到右逐条展开 */
    .vb-root {
      position: absolute; inset: 0; z-index: 3;
      display: flex; gap: 3px; padding: 0 2px;
      background: var(--mask-bg);
    }
    .vb-col { flex: 1; height: 100%; overflow: hidden; }
    .vb-col-inner {
      width: 100%; height: 100%;
      transform: scaleX(0);
      transform-origin: left center;
    }

    /* 2. 四分之一转盘：右下角 90° 扇形放射条 */
    .qf-root {
      position: absolute; inset: 0; z-index: 3;
      background: var(--mask-bg);
      clip-path: polygon(100% 0, 100% 100%, 0 100%);
    }
    .qf-blade {
      position: absolute; right: 0; bottom: 0;
      width: 160%; height: 8.5%;
      transform-origin: 100% 100%;
      overflow: hidden;
    }
    .qf-blade-inner {
      width: 100%; height: 100%;
      transform: scaleX(0);
      transform-origin: 100% 100%;
    }

    /* 3. 斜切遮罩：单条白色斜线对角扫过 */
    .dc-cover { position: absolute; inset: 0; z-index: 2; }
    .dc-line {
      position: absolute; left: 50%; top: 50%;
      width: 220%; height: 3px;
      margin-left: -110%;
      margin-top: -1.5px;
      background: rgba(255,255,255,.95);
      box-shadow: 0 0 6px rgba(255,255,255,.6);
      transform-origin: center center;
      transform: rotate(-38deg) translateY(120%);
      z-index: 3;
      pointer-events: none;
    }

    /* 4. 扇形擦除：底边中心弧形条逐条向上展开 */
    .sw-root {
      position: absolute; inset: 0; z-index: 3;
      pointer-events: none;
    }
    .sw-fan {
      position: absolute; left: 50%; bottom: 0;
      width: 130%; height: 92%;
      transform: translateX(-50%);
    }
    .sw-blade {
      position: absolute; left: 50%; bottom: 0;
      width: 22%; height: 100%;
      transform-origin: 50% 100%;
      overflow: hidden;
    }
    .sw-blade-cap {
      width: 100%; height: 100%;
      border-radius: 50% 50% 0 0 / 28% 28% 0 0;
      transform: scaleY(0);
      transform-origin: center bottom;
    }
    .sw-blade-cap.is-gap {
      background-color: #a8a8a8 !important;
      background-image: none !important;
    }

    @media (max-width: 600px) {
      .page { padding: 18px 14px 48px; }
      .tab-btn { min-width: calc(50% - 6px); font-size: 12px; }
    }