/* 51吃瓜外部CSS：高饱和度撞色、年轻街头、响应式视频卡片 */
:root{
  --blue:#0037ff;
  --pink:#ff00a8;
  --orange:#ffb400;
  --green:#6dff00;
  --black:#07070b;
  --white:#ffffff;
  --ink:#10101a;
  --muted:#6f7285;
  --panel:rgba(255,255,255,.88);
  --radius:28px;
  --shadow:0 24px 70px rgba(0,0,0,.22);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth;background:#050508}
body{margin:0;font-family:"Arial","Microsoft YaHei","PingFang SC",sans-serif;color:var(--ink);background:radial-gradient(circle at 10% 0%,rgba(0,55,255,.42),transparent 28%),radial-gradient(circle at 88% 8%,rgba(255,0,168,.42),transparent 25%),linear-gradient(135deg,#fff 0%,#f5f7ff 42%,#fff6df 100%);line-height:1.75;overflow-x:hidden}
a{color:inherit;text-decoration:none}
img,video{max-width:100%;display:block}
img{height:auto}
.visually-hidden{position:absolute;left:-9999px;width:1px;height:1px;overflow:hidden}
.site-header{position:relative;z-index:10;padding:18px clamp(16px,4vw,58px) 22px;background:linear-gradient(120deg,rgba(0,0,0,.92),rgba(0,55,255,.86),rgba(255,0,168,.88));color:#fff;overflow:hidden}
.header-glow{position:absolute;inset:-80px;background:radial-gradient(circle at 18% 30%,rgba(109,255,0,.38),transparent 18%),radial-gradient(circle at 75% 10%,rgba(255,180,0,.46),transparent 25%);filter:blur(6px);animation:drift 8s linear infinite alternate;pointer-events:none}
.nav-shell{position:relative;display:flex;align-items:center;justify-content:space-between;gap:24px;flex-wrap:wrap}
.brand-logo{display:inline-flex;align-items:center;gap:8px;font-weight:950;letter-spacing:.02em;text-transform:uppercase}
.logo-mark{display:inline-grid;place-items:center;width:58px;height:58px;border-radius:18px;background:linear-gradient(135deg,var(--green),var(--orange));color:#000;box-shadow:0 0 22px rgba(109,255,0,.7);font-size:28px;transform:rotate(-5deg)}
.logo-text{font-size:30px;text-shadow:3px 3px 0 var(--pink),-2px -2px 0 var(--blue)}
.brand-logo em{font-style:normal;font-size:12px;background:#fff;color:#000;border-radius:99px;padding:4px 8px;box-shadow:0 0 12px rgba(255,255,255,.72)}
.main-nav{display:flex;gap:10px;flex-wrap:wrap;align-items:center;justify-content:flex-end}
.main-nav a{padding:10px 14px;border:1px solid rgba(255,255,255,.36);border-radius:999px;background:rgba(255,255,255,.12);backdrop-filter:blur(10px);font-weight:800;transition:.22s ease}
.main-nav a:hover,.main-nav a:focus-visible{transform:translateY(-3px) rotate(-1deg);background:var(--orange);color:#000;box-shadow:0 0 0 4px rgba(255,255,255,.18),0 0 30px rgba(255,180,0,.7)}
.search-shell{position:relative;margin:18px auto 0;display:grid;grid-template-columns:1fr auto;gap:8px;max-width:980px;background:rgba(255,255,255,.17);padding:10px;border:1px solid rgba(255,255,255,.36);border-radius:26px;backdrop-filter:blur(12px);box-shadow:0 14px 36px rgba(0,0,0,.25)}
.search-shell input{border:0;border-radius:18px;padding:16px 18px;font-size:16px;outline:none;background:#fff;color:#08080b;font-weight:700}
.search-shell button,.cta,.pill-button{border:0;border-radius:18px;padding:15px 20px;font-size:16px;font-weight:950;background:linear-gradient(135deg,var(--orange),var(--green));color:#000;cursor:pointer;box-shadow:0 0 22px rgba(109,255,0,.5);transition:.2s ease}
.search-shell button:hover,.cta:hover,.pill-button:hover{transform:translateY(-2px) scale(1.03);filter:saturate(1.35)}
.search-note{grid-column:1/-1;margin:0;color:#fff;font-size:14px}
main{position:relative;z-index:1}
section{padding:clamp(46px,7vw,92px) clamp(16px,5vw,70px)}
.hero{display:grid;grid-template-columns:minmax(0,1.05fr) minmax(320px,.95fr);gap:28px;align-items:center;min-height:720px;background:linear-gradient(145deg,#050508,#101cff 48%,#ff00a8);color:#fff;position:relative;overflow:hidden}
.hero:before{content:"";position:absolute;inset:0;background-image:radial-gradient(circle,rgba(255,255,255,.34) 1px,transparent 2px);background-size:34px 34px;mask-image:linear-gradient(#000,transparent);animation:sparkle 12s linear infinite;pointer-events:none}
.hero-copy,.hero-card{position:relative;z-index:1}
.breadcrumb{display:flex;gap:9px;flex-wrap:wrap;margin-bottom:18px;color:rgba(255,255,255,.78);font-size:14px}
.eyebrow{display:inline-flex;align-items:center;gap:8px;padding:8px 12px;border-radius:999px;background:#fff;color:#000;font-weight:950;box-shadow:8px 8px 0 rgba(0,0,0,.45)}
h1,h2,h3,h4,h5,h6{line-height:1.12;margin:0 0 16px;font-weight:950;letter-spacing:-.03em}
h1{font-size:clamp(42px,8.4vw,110px);text-shadow:5px 5px 0 var(--pink),10px 10px 0 rgba(0,0,0,.28)}
h2{font-size:clamp(30px,5vw,64px)}
h3{font-size:clamp(22px,2.5vw,32px)}
h4{font-size:20px}
.lead{font-size:clamp(18px,2.2vw,25px);max-width:760px;color:rgba(255,255,255,.9)}
.hero-actions{display:flex;gap:14px;flex-wrap:wrap;margin-top:28px}
.cta.secondary{background:#fff;color:#000;box-shadow:0 0 22px rgba(255,255,255,.45)}
.hero-card{background:rgba(0,0,0,.44);border:2px solid rgba(255,255,255,.24);border-radius:38px;padding:16px;box-shadow:var(--shadow);transform:rotate(1.5deg)}
.video-card{position:relative;overflow:hidden;border-radius:32px;background:#08080d;color:#fff;box-shadow:var(--shadow);border:2px solid rgba(255,255,255,.15);isolation:isolate}
.video-card:before{content:"";position:absolute;inset:-2px;background:linear-gradient(135deg,var(--blue),var(--pink),var(--orange),var(--green));opacity:.0;transition:.25s ease;z-index:-1;filter:blur(20px)}
.video-card:hover:before{opacity:.9;animation:huePop .5s steps(2,end) infinite alternate}
.video-card:hover{transform:translateY(-8px) rotate(-1deg);box-shadow:0 0 0 5px rgba(255,255,255,.2),0 30px 90px rgba(255,0,168,.38)}
.video-card video,.video-card img{width:100%;aspect-ratio:16/9;object-fit:cover;filter:saturate(1.18);transition:.3s ease}
.video-card:hover video,.video-card:hover img{transform:scale(1.06);filter:saturate(1.65) contrast(1.12)}
.play-btn{position:absolute;inset:0;display:grid;place-items:center;opacity:0;transition:.22s ease;background:linear-gradient(transparent,rgba(0,0,0,.5))}
.play-btn span{display:grid;place-items:center;width:88px;height:88px;border-radius:50%;background:#fff;color:#000;font-size:40px;box-shadow:0 0 32px rgba(255,255,255,.85)}
.video-card:hover .play-btn{opacity:1}
.video-body{padding:20px}
.video-meta{display:flex;gap:10px;flex-wrap:wrap;color:#fff;font-weight:850;font-size:14px}
.video-meta span{padding:6px 10px;border-radius:999px;background:rgba(255,255,255,.14);border:1px solid rgba(255,255,255,.2)}
.tags{display:flex;gap:8px;flex-wrap:wrap;margin-top:12px}
.tags span{padding:5px 9px;border-radius:999px;background:rgba(109,255,0,.18);border:1px solid rgba(109,255,0,.48);color:#dfffca;font-weight:800;font-size:13px}
.section-head{display:flex;align-items:end;justify-content:space-between;gap:22px;flex-wrap:wrap;margin-bottom:28px}
.section-head p{max-width:720px;margin:0;color:#5e6274;font-size:18px}
.panel-light{background:rgba(255,255,255,.72);backdrop-filter:blur(15px);border:1px solid rgba(255,255,255,.8);border-radius:36px;box-shadow:0 20px 70px rgba(0,0,0,.12)}
.grid{display:grid;gap:22px}
.grid-3{grid-template-columns:repeat(3,minmax(0,1fr))}
.grid-4{grid-template-columns:repeat(4,minmax(0,1fr))}
.card{position:relative;background:var(--panel);border-radius:30px;padding:24px;border:1px solid rgba(255,255,255,.82);box-shadow:0 18px 48px rgba(0,0,0,.12);overflow:hidden}
.card:after{content:"";position:absolute;width:150px;height:150px;border-radius:50%;background:linear-gradient(135deg,var(--pink),var(--orange));right:-70px;top:-70px;opacity:.18}
.card strong{color:var(--blue)}
.card p{color:#5e6274;margin-bottom:0}
.card:hover{transform:translateY(-6px);box-shadow:0 24px 64px rgba(0,55,255,.18)}
.hot-section{background:#fff}
.community{background:linear-gradient(135deg,#fff6df,#f0fff4)}
.topic-stream{display:grid;grid-template-columns:1fr 1fr;gap:20px}
.topic-card{padding:20px;border-radius:24px;background:#08080d;color:#fff;border:1px solid rgba(255,255,255,.12);position:relative;overflow:hidden}
.topic-card b{color:var(--green)}
.topic-card:before{content:"弹幕";position:absolute;right:18px;top:12px;color:rgba(255,255,255,.12);font-size:48px;font-weight:950}
.ai-section{background:linear-gradient(135deg,#0a0a10,#141bff);color:#fff}
.ai-section .section-head p{color:rgba(255,255,255,.72)}
.ai-tool{background:rgba(255,255,255,.1);border-color:rgba(255,255,255,.16);color:#fff}
.ai-tool p{color:rgba(255,255,255,.76)}
.creator-card{display:grid;grid-template-columns:86px 1fr;gap:16px;align-items:center}
.avatar{width:86px;height:86px;border-radius:26px;background:linear-gradient(135deg,var(--blue),var(--pink),var(--orange));display:grid;place-items:center;color:#fff;font-size:28px;font-weight:950;box-shadow:0 0 28px rgba(255,0,168,.28)}
.reviews{background:#050508;color:#fff}
.reviews .section-head p{color:rgba(255,255,255,.74)}
.review-card{background:linear-gradient(145deg,rgba(255,255,255,.12),rgba(255,255,255,.05));color:#fff;border-color:rgba(255,255,255,.14)}
.review-card p{color:rgba(255,255,255,.76)}
.partners{background:#fff}
.logo-wall{display:grid;grid-template-columns:repeat(6,1fr);gap:12px;margin:22px 0}
.partner-logo{padding:18px 12px;border-radius:18px;background:linear-gradient(135deg,#f4f6ff,#fff7df);font-weight:950;text-align:center;border:1px solid #eceefa}
.faq-list{display:grid;gap:12px}
details{background:#fff;border:1px solid #edf0f8;border-radius:20px;padding:16px 18px;box-shadow:0 12px 32px rgba(0,0,0,.06)}
summary{font-weight:950;cursor:pointer}
.contact-section{background:linear-gradient(135deg,var(--orange),var(--pink));color:#fff}
.contact-section .card{color:#10101a}
.qr-row{display:flex;gap:18px;flex-wrap:wrap}
.qr-row figure{margin:0;background:#fff;color:#000;padding:12px;border-radius:22px;box-shadow:0 12px 30px rgba(0,0,0,.18);text-align:center;font-weight:850}
.qr-row img{width:150px;border-radius:14px}
.page-hero{min-height:420px;display:grid;align-items:center;background:linear-gradient(135deg,#07070b,#0037ff,#ff00a8);color:#fff;position:relative;overflow:hidden}
.page-hero:before{content:"";position:absolute;inset:0;background:radial-gradient(circle at 80% 10%,rgba(109,255,0,.42),transparent 26%),radial-gradient(circle at 20% 80%,rgba(255,180,0,.38),transparent 24%);pointer-events:none}
.page-hero>*{position:relative}
.content-split{display:grid;grid-template-columns:1fr .82fr;gap:28px;align-items:start}
.figure-card{margin:0;border-radius:34px;overflow:hidden;background:#fff;box-shadow:var(--shadow)}
.figure-card figcaption{padding:16px 20px;font-weight:800;color:#5e6274}
.site-footer{padding:48px clamp(16px,5vw,70px);background:#06060b;color:#fff}
.footer-top{display:grid;gap:12px;margin-bottom:26px}
.footer-top p{margin:0;color:rgba(255,255,255,.75)}
.footer-grid{display:grid;grid-template-columns:1fr auto;gap:24px;align-items:start}
.footer-links{list-style:none;padding:0;margin:0;display:flex;gap:10px;flex-wrap:wrap}
.footer-links a{display:inline-flex;padding:10px 12px;border-radius:999px;background:rgba(255,255,255,.1);border:1px solid rgba(255,255,255,.16);font-weight:800}
.back-top{display:inline-flex;margin-top:28px;padding:12px 16px;border-radius:999px;background:var(--green);color:#000;font-weight:950}
.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%) translateY(20px);opacity:0;background:#07070b;color:#fff;border:1px solid rgba(255,255,255,.22);border-radius:18px;padding:14px 18px;box-shadow:0 18px 42px rgba(0,0,0,.3);z-index:99;transition:.25s ease;font-weight:850}
.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
@keyframes drift{from{transform:translate3d(-1%,0,0)}to{transform:translate3d(2%,1%,0)}}
@keyframes sparkle{from{background-position:0 0}to{background-position:120px 240px}}
@keyframes huePop{from{filter:hue-rotate(0deg) blur(20px)}to{filter:hue-rotate(80deg) blur(22px)}}
@media (max-width:1000px){.hero,.content-split{grid-template-columns:1fr}.grid-4{grid-template-columns:repeat(2,1fr)}.grid-3{grid-template-columns:repeat(2,1fr)}.topic-stream{grid-template-columns:1fr}.logo-wall{grid-template-columns:repeat(3,1fr)}.footer-grid{grid-template-columns:1fr}.hero{min-height:auto}.main-nav{justify-content:flex-start}}
@media (max-width:640px){section{padding:42px 16px}.site-header{padding:14px}.search-shell{grid-template-columns:1fr}.grid-4,.grid-3{grid-template-columns:1fr}.logo-wall{grid-template-columns:repeat(2,1fr)}.logo-text{font-size:25px}.logo-mark{width:50px;height:50px}.main-nav a{font-size:14px;padding:8px 10px}h1{font-size:44px}.lead{font-size:17px}.hero-card{transform:none}.qr-row img{width:124px}}