/* roulang page: index */
:root{
      --bg:#06101f;
      --bg-2:#081a35;
      --panel:rgba(16, 38, 74, .58);
      --panel-strong:rgba(20, 48, 92, .78);
      --text:#eef6ff;
      --muted:#9fb4d0;
      --soft:#dbeafe;
      --line:rgba(148, 163, 184, .20);
      --primary:#3b82f6;
      --primary-2:#22d3ee;
      --accent:#a78bfa;
      --green:#34d399;
      --warning:#fbbf24;
      --danger:#fb7185;
      --radius-sm:12px;
      --radius:20px;
      --radius-lg:30px;
      --shadow:0 24px 80px rgba(2, 8, 23, .40);
      --shadow-glow:0 0 38px rgba(34, 211, 238, .22), 0 18px 70px rgba(59, 130, 246, .20);
      --container:1180px;
    }

    *{box-sizing:border-box;}
    html{scroll-behavior:smooth;}
    body{
      margin:0;
      min-height:100vh;
      font-family:Inter, "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", system-ui, sans-serif;
      color:var(--text);
      background:
        radial-gradient(circle at 18% 8%, rgba(59,130,246,.25), transparent 33%),
        radial-gradient(circle at 85% 12%, rgba(34,211,238,.22), transparent 28%),
        radial-gradient(circle at 55% 72%, rgba(167,139,250,.16), transparent 30%),
        linear-gradient(180deg, #051024 0%, #081a35 45%, #050b18 100%);
      line-height:1.7;
      overflow-x:hidden;
    }

    body::before{
      content:"";
      position:fixed;
      inset:0;
      pointer-events:none;
      background-image:
        linear-gradient(rgba(255,255,255,.035) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255,255,255,.035) 1px, transparent 1px);
      background-size:48px 48px;
      mask-image:linear-gradient(to bottom, rgba(0,0,0,.9), transparent 78%);
      z-index:-2;
    }

    a{color:inherit;text-decoration:none;}
    img{max-width:100%;display:block;}
    button,input,select,textarea{font:inherit;}
    button{cursor:pointer;}
    ::selection{background:rgba(34,211,238,.28);color:#fff;}

    .site-container{
      width:min(var(--container), calc(100% - 40px));
      margin-inline:auto;
    }

    .glass{
      background:linear-gradient(145deg, rgba(15, 35, 70, .72), rgba(8, 24, 50, .50));
      border:1px solid var(--line);
      box-shadow:var(--shadow);
      backdrop-filter:blur(18px);
      -webkit-backdrop-filter:blur(18px);
    }

    .soft-card{
      position:relative;
      overflow:hidden;
      border-radius:var(--radius);
      border:1px solid var(--line);
      background:linear-gradient(160deg, rgba(255,255,255,.08), rgba(255,255,255,.035));
      box-shadow:0 16px 48px rgba(2, 8, 23, .22);
      transition:transform .25s ease, border-color .25s ease, box-shadow .25s ease, background .25s ease;
    }

    .soft-card:hover{
      transform:translateY(-4px);
      border-color:rgba(34,211,238,.42);
      box-shadow:var(--shadow-glow);
      background:linear-gradient(160deg, rgba(255,255,255,.105), rgba(255,255,255,.045));
    }

    .badge{
      display:inline-flex;
      align-items:center;
      gap:.45rem;
      min-height:34px;
      padding:6px 12px;
      border-radius:999px;
      border:1px solid rgba(34,211,238,.28);
      background:rgba(34,211,238,.10);
      color:#baf4ff;
      font-size:13px;
      font-weight:700;
      letter-spacing:.02em;
    }

    .badge::before{
      content:"";
      width:7px;
      height:7px;
      border-radius:999px;
      background:var(--primary-2);
      box-shadow:0 0 14px rgba(34,211,238,.8);
    }

    .btn{
      display:inline-flex;
      align-items:center;
      justify-content:center;
      gap:.55rem;
      min-height:46px;
      padding:12px 18px;
      border-radius:999px;
      border:1px solid transparent;
      font-weight:800;
      letter-spacing:.01em;
      transition:transform .22s ease, box-shadow .22s ease, background .22s ease, border-color .22s ease, color .22s ease;
      outline:none;
      user-select:none;
      white-space:nowrap;
    }

    .btn:focus-visible,
    .nav-link:focus-visible,
    .search-input:focus-visible,
    input:focus-visible,
    select:focus-visible,
    textarea:focus-visible{
      outline:3px solid rgba(34,211,238,.35);
      outline-offset:3px;
    }

    .btn-primary{
      color:#04111f;
      background:linear-gradient(135deg, #67e8f9 0%, #60a5fa 45%, #a78bfa 100%);
      box-shadow:0 0 34px rgba(34,211,238,.34), 0 16px 34px rgba(59,130,246,.28);
    }

    .btn-primary:hover{
      transform:translateY(-2px);
      box-shadow:0 0 46px rgba(34,211,238,.50), 0 22px 42px rgba(59,130,246,.34);
    }

    .btn-ghost{
      color:var(--soft);
      background:rgba(255,255,255,.06);
      border-color:rgba(148,163,184,.24);
    }

    .btn-ghost:hover{
      transform:translateY(-2px);
      border-color:rgba(34,211,238,.42);
      background:rgba(34,211,238,.10);
    }

    .section{
      padding:88px 0;
      position:relative;
    }

    .section-tight{padding:64px 0;}
    .section-title{
      font-size:clamp(28px, 4vw, 46px);
      line-height:1.15;
      letter-spacing:-.04em;
      font-weight:900;
      color:#fff;
    }

    .section-desc{
      margin-top:16px;
      color:var(--muted);
      font-size:16px;
      max-width:760px;
    }

    .header{
      position:sticky;
      top:0;
      z-index:50;
      border-bottom:1px solid rgba(148,163,184,.18);
      background:rgba(5, 13, 29, .70);
      backdrop-filter:blur(22px);
      -webkit-backdrop-filter:blur(22px);
    }

    .nav-shell{
      height:76px;
      display:flex;
      align-items:center;
      justify-content:space-between;
      gap:18px;
    }

    .brand{
      display:flex;
      align-items:center;
      gap:12px;
      min-width:max-content;
    }

    .brand-mark{
      width:42px;
      height:42px;
      display:grid;
      place-items:center;
      border-radius:14px;
      background:linear-gradient(135deg, #1d4ed8, #22d3ee);
      box-shadow:0 0 26px rgba(34,211,238,.35);
      font-weight:950;
      color:#fff;
      letter-spacing:-.05em;
    }

    .brand-text{
      display:flex;
      flex-direction:column;
      line-height:1.15;
    }

    .brand-name{
      font-weight:950;
      letter-spacing:-.03em;
      font-size:16px;
    }

    .brand-sub{
      color:var(--muted);
      font-size:12px;
      margin-top:3px;
    }

    .nav-center{
      display:flex;
      align-items:center;
      justify-content:center;
      padding:6px;
      border-radius:999px;
      background:rgba(255,255,255,.045);
      border:1px solid rgba(148,163,184,.16);
    }

    .nav-link{
      display:inline-flex;
      align-items:center;
      min-height:36px;
      padding:8px 16px;
      border-radius:999px;
      color:#c7d7ee;
      font-weight:750;
      font-size:14px;
      transition:background .2s ease, color .2s ease, box-shadow .2s ease;
    }

    .nav-link:hover,
    .nav-link.active{
      color:#fff;
      background:rgba(34,211,238,.12);
      box-shadow:inset 0 0 0 1px rgba(34,211,238,.18);
    }

    .nav-actions{
      display:flex;
      align-items:center;
      justify-content:flex-end;
      gap:10px;
      min-width:310px;
    }

    .command-search{
      height:42px;
      width:210px;
      display:flex;
      align-items:center;
      gap:8px;
      border-radius:999px;
      padding:0 12px;
      color:#8ea4c2;
      background:rgba(255,255,255,.055);
      border:1px solid rgba(148,163,184,.18);
      transition:border-color .2s ease, background .2s ease, box-shadow .2s ease;
    }

    .command-search:hover{
      border-color:rgba(34,211,238,.34);
      background:rgba(255,255,255,.075);
    }

    .search-input{
      width:100%;
      color:#fff;
      background:transparent;
      border:0;
      outline:0;
      font-size:13px;
    }

    .search-input::placeholder{color:#8ea4c2;}

    .kbd{
      flex:0 0 auto;
      padding:1px 7px;
      border-radius:7px;
      border:1px solid rgba(148,163,184,.22);
      background:rgba(2,8,23,.32);
      color:#b8c6dc;
      font-size:11px;
    }

    .mobile-toggle{
      display:none;
      width:44px;
      height:44px;
      border-radius:14px;
      border:1px solid rgba(148,163,184,.20);
      background:rgba(255,255,255,.06);
      color:#fff;
    }

    .hero{
      min-height:calc(100vh - 76px);
      display:flex;
      align-items:center;
      padding:72px 0 92px;
      overflow:hidden;
    }

    .hero-wrap{
      display:grid;
      grid-template-columns:1.05fr .95fr;
      gap:42px;
      align-items:center;
    }

    .hero-copy{
      max-width:720px;
      position:relative;
      z-index:2;
    }

    .hero h1{
      margin:22px 0 0;
      max-width:820px;
      font-size:clamp(42px, 7vw, 84px);
      line-height:.98;
      letter-spacing:-.075em;
      font-weight:950;
      color:#fff;
      text-wrap:balance;
    }

    .hero-lead{
      margin-top:24px;
      max-width:680px;
      color:#c5d4ea;
      font-size:clamp(16px, 2vw, 20px);
      line-height:1.85;
    }

    .hero-actions{
      margin-top:32px;
      display:flex;
      flex-wrap:wrap;
      gap:14px;
      align-items:center;
    }

    .hero-metrics{
      margin-top:34px;
      display:grid;
      grid-template-columns:repeat(3, minmax(0, 1fr));
      gap:14px;
      max-width:680px;
    }

    .metric{
      padding:18px;
      border-radius:18px;
      background:rgba(255,255,255,.055);
      border:1px solid rgba(148,163,184,.16);
    }

    .metric strong{
      display:block;
      font-size:24px;
      color:#fff;
      line-height:1;
    }

    .metric span{
      display:block;
      margin-top:8px;
      color:var(--muted);
      font-size:13px;
    }

    .vertical-stage{
      position:relative;
      min-height:610px;
      display:grid;
      place-items:center;
      isolation:isolate;
    }

    .vertical-stage::before{
      content:"";
      position:absolute;
      width:430px;
      height:430px;
      border-radius:999px;
      background:radial-gradient(circle, rgba(34,211,238,.22), transparent 67%);
      filter:blur(6px);
      z-index:-1;
    }

    .video-card{
      position:absolute;
      width:245px;
      min-height:430px;
      padding:18px;
      border-radius:34px;
      border:1px solid rgba(255,255,255,.17);
      background:
        linear-gradient(180deg, rgba(255,255,255,.13), rgba(255,255,255,.045)),
        radial-gradient(circle at 30% 8%, rgba(34,211,238,.28), transparent 34%),
        radial-gradient(circle at 78% 60%, rgba(167,139,250,.25), transparent 36%);
      box-shadow:0 30px 90px rgba(0,0,0,.38);
      backdrop-filter:blur(18px);
      overflow:hidden;
      transition:transform .25s ease, box-shadow .25s ease;
    }

    .video-card:hover{
      box-shadow:0 0 46px rgba(34,211,238,.20), 0 40px 100px rgba(0,0,0,.46);
    }

    .video-card.main{
      transform:translateY(0) rotate(0deg);
      z-index:3;
    }

    .video-card.left{
      transform:translateX(-145px) translateY(42px) rotate(-10deg) scale(.88);
      opacity:.75;
      z-index:1;
    }

    .video-card.right{
      transform:translateX(145px) translateY(-34px) rotate(9deg) scale(.90);
      opacity:.82;
      z-index:2;
    }

    .short-cover{
      height:210px;
      border-radius:24px;
      background:
        linear-gradient(160deg, rgba(2,8,23,.15), rgba(2,8,23,.55)),
        radial-gradient(circle at 32% 30%, rgba(103,232,249,.50), transparent 22%),
        radial-gradient(circle at 68% 68%, rgba(96,165,250,.45), transparent 28%),
        linear-gradient(135deg, #123566, #0e1d3a);
      border:1px solid rgba(255,255,255,.14);
      position:relative;
      overflow:hidden;
    }

    .short-cover::after{
      content:"";
      position:absolute;
      inset:auto 16px 16px 16px;
      height:46px;
      border-radius:18px;
      background:rgba(255,255,255,.10);
      border:1px solid rgba(255,255,255,.12);
    }

    .play-dot{
      position:absolute;
      top:50%;
      left:50%;
      width:58px;
      height:58px;
      transform:translate(-50%,-50%);
      border-radius:999px;
      display:grid;
      place-items:center;
      color:#04111f;
      background:linear-gradient(135deg, #67e8f9, #a78bfa);
      box-shadow:0 0 34px rgba(34,211,238,.36);
      font-weight:950;
    }

    .card-chip-row{
      display:flex;
      flex-wrap:wrap;
      gap:8px;
      margin:16px 0 14px;
    }

    .mini-chip{
      padding:5px 9px;
      border-radius:999px;
      color:#c8e8ff;
      font-size:12px;
      border:1px solid rgba(148,163,184,.18);
      background:rgba(255,255,255,.06);
    }

    .video-title{
      font-size:20px;
      line-height:1.25;
      font-weight:900;
      color:#fff;
    }

    .video-desc{
      margin-top:10px;
      color:#b8c6dc;
      font-size:13px;
      line-height:1.65;
    }

    .progress-line{
      margin-top:16px;
      height:8px;
      border-radius:999px;
      background:rgba(255,255,255,.08);
      overflow:hidden;
    }

    .progress-line span{
      display:block;
      height:100%;
      width:76%;
      border-radius:999px;
      background:linear-gradient(90deg, var(--primary-2), var(--accent));
      box-shadow:0 0 18px rgba(34,211,238,.4);
    }

    .step-list{
      display:grid;
      gap:14px;
    }

    .step-item{
      display:grid;
      grid-template-columns:48px 1fr;
      gap:16px;
      padding:18px;
      border-radius:20px;
      border:1px solid rgba(148,163,184,.18);
      background:rgba(255,255,255,.055);
    }

    .step-num{
      width:48px;
      height:48px;
      display:grid;
      place-items:center;
      border-radius:16px;
      color:#04111f;
      font-weight:950;
      background:linear-gradient(135deg, #67e8f9, #60a5fa);
    }

    .table-wrap{
      overflow:auto;
      border-radius:22px;
      border:1px solid rgba(148,163,184,.18);
      background:rgba(255,255,255,.04);
    }

    .rank-table{
      width:100%;
      min-width:720px;
      border-collapse:collapse;
      font-size:14px;
    }

    .rank-table th,
    .rank-table td{
      padding:17px 18px;
      text-align:left;
      border-bottom:1px solid rgba(148,163,184,.14);
      white-space:nowrap;
    }

    .rank-table th{
      color:#d8e9ff;
      background:rgba(255,255,255,.055);
      font-size:13px;
      letter-spacing:.03em;
    }

    .rank-table tr:last-child td{border-bottom:0;}
    .rank-table tbody tr{transition:background .2s ease;}
    .rank-table tbody tr:hover{background:rgba(34,211,238,.07);}

    .trend-up{color:var(--green);font-weight:800;}
    .trend-hot{color:#fcd34d;font-weight:800;}
    .trend-new{color:#93c5fd;font-weight:800;}

    .news-link{
      display:grid;
      grid-template-columns:96px 1fr auto;
      gap:16px;
      align-items:center;
      padding:18px;
      border-radius:18px;
      border:1px solid rgba(148,163,184,.15);
      background:rgba(255,255,255,.045);
      transition:background .2s ease, border-color .2s ease, transform .2s ease;
    }

    .news-link:hover{
      transform:translateX(4px);
      border-color:rgba(34,211,238,.35);
      background:rgba(34,211,238,.075);
    }

    .news-tag{
      display:inline-flex;
      justify-content:center;
      padding:6px 10px;
      border-radius:999px;
      color:#baf4ff;
      border:1px solid rgba(34,211,238,.24);
      background:rgba(34,211,238,.09);
      font-size:12px;
      font-weight:800;
    }

    .faq-item{
      border:1px solid rgba(148,163,184,.18);
      background:rgba(255,255,255,.045);
      border-radius:20px;
      overflow:hidden;
    }

    .faq-question{
      width:100%;
      min-height:64px;
      padding:18px 20px;
      display:flex;
      justify-content:space-between;
      align-items:center;
      gap:18px;
      color:#fff;
      text-align:left;
      background:transparent;
      border:0;
      font-weight:900;
    }

    .faq-question span:last-child{
      width:30px;
      height:30px;
      display:grid;
      place-items:center;
      border-radius:999px;
      background:rgba(34,211,238,.10);
      color:#baf4ff;
      flex:0 0 auto;
      transition:transform .2s ease;
    }

    .faq-answer{
      display:none;
      padding:0 20px 20px;
      color:#adc0da;
      font-size:15px;
      line-height:1.85;
    }

    .faq-item.open .faq-answer{display:block;}
    .faq-item.open .faq-question span:last-child{transform:rotate(45deg);}

    .form-field label{
      display:block;
      margin-bottom:8px;
      color:#dbeafe;
      font-size:14px;
      font-weight:800;
    }

    .form-field input,
    .form-field select,
    .form-field textarea{
      width:100%;
      border:1px solid rgba(148,163,184,.22);
      border-radius:16px;
      background:rgba(2,8,23,.30);
      color:#fff;
      padding:13px 14px;
      outline:0;
      transition:border-color .2s ease, box-shadow .2s ease, background .2s ease;
    }

    .form-field input::placeholder,
    .form-field textarea::placeholder{color:#7f93b2;}

    .form-field input:focus,
    .form-field select:focus,
    .form-field textarea:focus{
      border-color:rgba(34,211,238,.46);
      background:rgba(2,8,23,.42);
      box-shadow:0 0 0 4px rgba(34,211,238,.09);
    }

    .site-footer{
      padding:56px 0 34px;
      background:linear-gradient(180deg, rgba(2,8,23,.12), rgba(2,8,23,.60));
      border-top:1px solid rgba(148,163,184,.16);
    }

    .footer-link{
      color:#b8c6dc;
      transition:color .2s ease;
    }

    .footer-link:hover{color:#67e8f9;}

    .bottom-cta{
      position:fixed;
      left:50%;
      bottom:18px;
      transform:translateX(-50%);
      z-index:40;
      width:min(720px, calc(100% - 28px));
      display:flex;
      align-items:center;
      justify-content:space-between;
      gap:14px;
      padding:12px 14px 12px 18px;
      border-radius:999px;
      background:rgba(5, 16, 34, .78);
      border:1px solid rgba(34,211,238,.24);
      box-shadow:0 18px 60px rgba(2,8,23,.46), 0 0 34px rgba(34,211,238,.12);
      backdrop-filter:blur(18px);
    }

    .bottom-cta p{
      margin:0;
      color:#dbeafe;
      font-size:14px;
      font-weight:750;
    }

    @media (max-width:1024px){
      .nav-actions{min-width:auto;}
      .command-search{width:178px;}
      .hero-wrap{grid-template-columns:1fr;gap:26px;}
      .hero{padding-top:54px;}
      .vertical-stage{min-height:520px;}
      .video-card.left{transform:translateX(-118px) translateY(44px) rotate(-9deg) scale(.82);}
      .video-card.right{transform:translateX(118px) translateY(-26px) rotate(8deg) scale(.84);}
    }

    @media (max-width:768px){
      .site-container{width:min(100% - 28px, var(--container));}
      .nav-shell{height:auto;min-height:70px;flex-wrap:wrap;padding:12px 0;}
      .nav-center{
        order:3;
        width:100%;
        justify-content:flex-start;
        overflow-x:auto;
      }
      .nav-actions{display:none;}
      .nav-actions.open{
        order:4;
        width:100%;
        display:flex;
        flex-direction:column;
        align-items:stretch;
        padding:12px;
        border-radius:20px;
        border:1px solid rgba(148,163,184,.16);
        background:rgba(255,255,255,.045);
      }
      .nav-actions.open .command-search{width:100%;}
      .mobile-toggle{display:grid;place-items:center;}
      .hero{min-height:auto;padding:46px 0 70px;}
      .hero-metrics{grid-template-columns:1fr;}
      .vertical-stage{min-height:480px;transform:scale(.92);}
      .section{padding:66px 0;}
      .news-link{grid-template-columns:1fr;gap:10px;}
      .bottom-cta{
        align-items:stretch;
        flex-direction:column;
        border-radius:24px;
        padding:14px;
      }
      .bottom-cta .btn{width:100%;}
    }

    @media (max-width:520px){
      .brand-name{font-size:14px;max-width:180px;}
      .brand-sub{display:none;}
      .brand-mark{width:38px;height:38px;border-radius:13px;}
      .hero h1{font-size:42px;}
      .hero-actions .btn{width:100%;}
      .vertical-stage{min-height:440px;transform:scale(.82);margin-top:-20px;}
      .video-card{width:228px;min-height:408px;}
      .video-card.left{transform:translateX(-82px) translateY(58px) rotate(-8deg) scale(.76);}
      .video-card.right{transform:translateX(82px) translateY(-30px) rotate(8deg) scale(.78);}
      .section-title{font-size:30px;}
      .step-item{grid-template-columns:1fr;}
      .table-wrap{margin-inline:-2px;}
    }