:root{--radius-sm:12px;--radius-lg:18px;--transition-base:0.2s ease}h1,h2,h3,h4,h5,h6{font-weight:600;margin:0 0 .75em;color:var(--text-1)}p{margin:0 0 1em}.text-muted{color:var(--text-2)!important}.shadow-card{box-shadow:var(--shadow-sm);border-radius:var(--radius-lg);border:1px solid var(--border);background:var(--bg-card)}.badge-soft{display:inline-flex;align-items:center;justify-content:center;padding:.35rem .75rem;border-radius:999px;font-size:.75rem;font-weight:600;background:var(--accent-soft);color:var(--brand-color)}.ratio{background:#000}.language-selector button{border-radius:999px}*,::after,::before{box-sizing:border-box}body,html{margin:0;padding:0}body{font-family:Inter,"Segoe UI","Microsoft YaHei","PingFang SC",sans-serif;background:var(--bg-page);color:var(--text-1);line-height:1.6;-webkit-font-smoothing:antialiased}img,video{max-width:100%;display:block}a{text-decoration:none;color:inherit;transition:color .2s ease}a:hover{color:var(--brand-color)}ol,ul{margin:0;padding:0;list-style:none}button{font:inherit;cursor:pointer}.site-body{position:relative;background:linear-gradient(180deg,rgba(6,12,27,.95),rgba(10,17,34,.94) 45%,rgba(15,23,42,.9)),url('../image/backgroud.jpg') center/cover fixed no-repeat;min-height:100vh;display:flex;flex-direction:column}.site-main{flex:1 0 auto;display:flex;justify-content:center;padding:clamp(1rem,2.5vw,1.75rem) clamp(1rem,3vw,2.25rem) clamp(2rem,5vw,3.25rem)}.site-main>*{width:100%}.site-topbar{flex:0 0 auto;padding:.75rem clamp(1rem,3vw,2.5rem) 0}.topbar-inner{display:flex;justify-content:flex-end;max-width:min(1200px,92vw);margin:0 auto}.language-menu{display:inline-flex;align-items:center;gap:.5rem;padding:.5rem .75rem;border-radius:999px;background:rgba(15,23,42,.82);border:1px solid rgba(148,197,255,.32);backdrop-filter:blur(12px)}.language-link{display:inline-flex;align-items:center;justify-content:center;padding:.3rem .85rem;border-radius:999px;font-size:.85rem;color:rgba(226,232,240,.82);border:1px solid transparent;transition:color .2s ease,border-color .2s ease,background .2s ease}.language-link:focus,.language-link:hover{text-decoration:none;color:#f8fafc;border-color:rgba(148,197,255,.55);background:rgba(59,130,246,.22)}.language-link.is-active{color:#0b1220;background:#f8fafc}@media (max-width:575.98px){.site-topbar{padding-top:.5rem}.topbar-inner{justify-content:center}.language-menu{flex-wrap:wrap;justify-content:center}}.navbar-modern .nav-link{padding:.65rem .9rem;border-radius:999px;transition:background-color .2s ease,color .2s ease}.navbar-modern .nav-link.active,.navbar-modern .nav-link:hover{background:var(--accent-soft);color:var(--brand-color)}.navbar-actions .btn{min-width:118px}.btn-primary{background:var(--brand-color);border-color:var(--brand-color)}.btn-primary:focus,.btn-primary:hover{background:var(--brand-color-600);border-color:var(--brand-color-600)}.btn-outline-secondary{border-color:rgba(148,163,184,.45);color:rgba(226,232,240,.86)}.btn-outline-secondary:focus,.btn-outline-secondary:hover{color:#f8fafc;border-color:rgba(148,197,255,.65);background:rgba(59,130,246,.18)}.section{background:var(--bg-card);border:1px solid var(--border);border-radius:18px;padding:32px;box-shadow:var(--shadow-sm)}@media (max-width:575.98px){.section{padding:24px}}.eyebrow{font-size:.85rem;letter-spacing:.08em;color:var(--brand-color);margin-bottom:.75rem}.headline{font-size:clamp(2rem, 3vw + 1rem, 3rem);font-weight:700;margin-bottom:1rem}.lead-text{font-size:1.1rem;color:var(--text-2)}.hero-points{margin-top:1.5rem;display:grid;gap:.75rem;color:var(--text-2)}.hero-points li{display:flex;align-items:flex-start;gap:.5rem}.hero-points li::before{content:"";flex-shrink:0;height:8px;width:8px;margin-top:.45rem;border-radius:50%;background:var(--brand-color)}.tutorial-video,.video-frame{border-radius:16px;overflow:hidden;box-shadow:var(--shadow-md)}.tutorial-card{background:var(--bg-card);border:1px solid var(--border);border-radius:16px;box-shadow:var(--shadow-sm);padding:20px;height:100%;display:flex;flex-direction:column;gap:16px}.tutorial-card img{border-radius:12px}.tutorial-card figcaption{font-weight:600;font-size:1.05rem}.tutorial-card p{color:var(--text-2)}.cta-card{background:var(--accent-gradient);border:1px solid rgba(59,130,246,.28);border-radius:18px;padding:28px;box-shadow:var(--shadow-sm)}.guarantee-list{display:grid;gap:.75rem;color:var(--text-2);padding-left:0}.guarantee-list li{position:relative;padding-left:1.6rem}.guarantee-list li::before{content:"✓";position:absolute;left:0;top:0;font-weight:700;color:var(--brand-color)}.site-footer{background:var(--bg-card);border-top:1px solid var(--border)}.site-footer .record-icon{height:20px;width:20px}.site-footer .text-muted{color:var(--text-2)!important}.page-heading{display:flex;flex-direction:column;gap:.75rem}.page-heading .badge-soft{align-self:flex-start}.language-wrap .dropdown-toggle{display:inline-flex;align-items:center;justify-content:center;gap:.35rem;padding:.4rem .9rem;border-radius:999px;border:1px solid var(--border);color:var(--text-2);font-size:.85rem}.language-wrap .dropdown-toggle:focus,.language-wrap .dropdown-toggle:hover{color:var(--brand-color);border-color:var(--brand-color)}.language-wrap .dropdown-menu{border-radius:14px;border-color:var(--border);box-shadow:var(--shadow-md)}::-webkit-scrollbar{width:.475rem;height:.475rem}::-webkit-scrollbar-thumb{border-radius:10px;background-color:var(--brand-color);background-image:-webkit-linear-gradient(45deg,rgba(255,255,255,.3) 25%,transparent 25%,transparent 50%,rgba(255,255,255,.3) 50%,rgba(255,255,255,.3) 75%,transparent 75%,transparent)}::-webkit-scrollbar-track{box-shadow:inset 0 0 5px rgba(0,0,0,.2);background:#ededed;border-radius:10px}:root{--brand-color:#3b82f6;--brand-color-500:#60a5fa;--brand-color-600:#2563eb;--brand-color-700:#1d4ed8;--accent-soft:rgba(59, 130, 246, 0.18);--accent-gradient:linear-gradient(135deg, rgba(37, 99, 235, 0.22), rgba(14, 116, 144, 0.12));--text-1:#e2e8f0;--text-2:rgba(148, 163, 184, 0.82);--bg-page:#0b1220;--bg-card:rgba(15, 23, 42, 0.9);--border:rgba(148, 163, 184, 0.18);--shadow-sm:0 14px 40px rgba(8, 25, 52, 0.42);--shadow-md:0 22px 55px rgba(15, 23, 42, 0.55)}body,html{background:var(--bg-page);color:var(--text-1)}a{color:#93c5fd}a:hover{color:#bfdbfe}.site-body{background:var(--bg-page)}.navbar-modern{backdrop-filter:saturate(180%) blur(10px);background:rgba(15,23,42,.85)!important;border-bottom:1px solid var(--border)}.navbar-brand img{height:36px;width:36px;border-radius:50%;margin-right:.5rem}.navbar-nav .nav-link{font-weight:500;color:rgba(226,232,240,.78)}.navbar-nav .nav-link.active,.navbar-nav .nav-link:hover{color:var(--brand-color)}.site-footer{background:rgba(10,17,30,.95);border-top:1px solid var(--border)}.site-footer a,.site-footer p{color:rgba(203,213,225,.78)}.section{border-radius:18px;padding:32px}.muted{color:var(--text-2)}