@import url('https://fonts.googleapis.com/css2?family=Noto+Sans+SC:wght@400;500;700;900&display=swap');

/* ============ 气泡花园 · 贴图聊天(LINE 绿 · 浅色) ============ */
:root{
  --bg0:#f5faf7; --bg1:#ffffff; --bg2:#eef7f1;
  --card:#ffffff; --card2:#eef7f1;
  --stroke:#e2efe8; --stroke2:#cfe6da;
  --fg:#17301f; --fg-soft:#3d5447; --muted:#6f8a7a;
  --acc:#06c755; --acc-deep:#04a342; --acc-soft:rgba(6,199,85,.12);
  --acc2:#ffb020; --acc2-soft:rgba(255,176,32,.14);
  --grad:linear-gradient(135deg,#06c755,#04a342);
  --grad2:linear-gradient(135deg,#06c755,#ffb020);
  --good:#06c755; --danger:#e23a5c;
  --shadow:0 22px 55px rgba(18,86,52,.12); --shadow-sm:0 8px 26px rgba(18,86,52,.08);
  --r:18px; --rl:26px;
  --font-d:'Noto Sans SC','PingFang SC','Microsoft YaHei',system-ui,sans-serif;
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg0);color:var(--fg);font:16px/1.75 var(--font-d);-webkit-font-smoothing:antialiased}
img{max-width:100%}
a{color:var(--acc);text-decoration:none}
h1,h2,h3,h4{font-family:var(--font-d);line-height:1.3;color:var(--fg);margin:0 0 12px}
h2{font-size:29px;letter-spacing:-.3px}
p{margin:0 0 14px}
.wrap{max-width:1160px;margin:0 auto;padding:0 22px}
::selection{background:rgba(6,199,85,.22)}

/* ---------- 基元 ---------- */
.glass{background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);box-shadow:var(--shadow-sm)}

/* ---------- 按钮:胶囊(主=LINE 绿渐变,副=描边) ---------- */
.btn{display:inline-flex;align-items:center;justify-content:center;gap:9px;border-radius:999px;font-family:var(--font-d);font-weight:700;font-size:15.5px;padding:14px 26px;border:1px solid transparent;cursor:pointer;text-decoration:none;transition:.22s;white-space:nowrap}
.btn svg{flex:none}
.btn-primary{background:var(--grad);color:#fff;border:none;box-shadow:0 10px 28px rgba(6,199,85,.34)}
.btn-primary:hover{transform:translateY(-2px);box-shadow:0 16px 38px rgba(6,199,85,.46);color:#fff}
.btn-ghost{background:var(--card);color:var(--fg);border-color:var(--stroke2);box-shadow:var(--shadow-sm)}
.btn-ghost:hover{border-color:var(--acc);color:var(--acc)}
.btn-outline{background:transparent;color:var(--acc-deep);border-color:rgba(6,199,85,.5)}
.btn-outline:hover{background:var(--acc-soft)}
.btn-lg{padding:17px 34px;font-size:17px}
.btn-sm{padding:10px 18px;font-size:14px}

/* ---------- 顶导航:白底悬浮条 ---------- */
.masthead{position:sticky;top:0;z-index:70;background:rgba(255,255,255,.9);backdrop-filter:blur(14px);-webkit-backdrop-filter:blur(14px);border-bottom:1px solid var(--stroke)}
.masthead .wrap{display:flex;align-items:center;gap:18px;height:66px}
.wordmark{display:flex;align-items:center;gap:11px;text-decoration:none;color:var(--fg)}
.wm-mark{width:40px;height:40px;object-fit:contain;flex:0 0 auto}
.wm-text{display:flex;flex-direction:column;line-height:1.15}
.wm-name{font-family:var(--font-d);font-weight:900;font-size:18px;color:var(--fg)}
.wm-sub{font-size:9.5px;letter-spacing:2px;color:var(--acc);font-weight:700}
.nav-wrap{margin-left:auto;display:flex;align-items:center;gap:4px}
.nav-wrap>a{position:relative;padding:8px 13px;color:var(--fg-soft);text-decoration:none;font-size:14.5px;border-radius:999px}
.nav-wrap>a:hover,.nav-wrap>a.on{color:var(--acc-deep);background:var(--acc-soft)}
.dd{position:relative}
.dd>button{background:none;border:none;color:var(--fg-soft);font:inherit;font-size:14.5px;padding:8px 13px;border-radius:999px;cursor:pointer}
.dd>button:hover{color:var(--acc-deep);background:var(--acc-soft)}
.dd-menu{position:absolute;top:calc(100% + 8px);left:0;min-width:200px;padding:8px;border-radius:16px;background:#fff;border:1px solid var(--stroke);box-shadow:var(--shadow);display:flex;flex-direction:column;opacity:0;visibility:hidden;transform:translateY(-6px);transition:.2s}
.dd:hover .dd-menu{opacity:1;visibility:visible;transform:none}
.dd-menu a{padding:9px 13px;color:var(--fg-soft);border-radius:10px;font-size:14px}
.dd-menu a:hover{color:var(--acc-deep);background:var(--acc-soft)}
.nav-cta{margin-left:4px}
.nav-toggle{display:none;background:none;border:1px solid var(--stroke2);color:var(--fg);border-radius:10px;width:40px;height:40px;font-size:20px;cursor:pointer}

/* ---------- 分屏 hero(浅色) ---------- */
.hero{position:relative;padding:104px 0 96px;overflow:hidden;background:radial-gradient(1000px 520px at 82% 8%,rgba(6,199,85,.14),transparent 60%),radial-gradient(720px 420px at 12% 96%,rgba(255,176,32,.10),transparent 60%),var(--bg0)}
.hero-bg{display:none}
.hero-veil{display:none}
.hero .wrap{position:relative;z-index:2}
.hero-grid{display:grid;grid-template-columns:1.1fr .9fr;gap:54px;align-items:center}
.hero-left{min-width:0}
.hero-side{min-width:0;display:flex;justify-content:flex-end}
.hero-kicker{display:inline-flex;align-items:center;gap:9px;font-size:12.5px;letter-spacing:3px;color:var(--acc-deep);font-weight:700;margin-bottom:20px}
.hero-kicker .dot{width:8px;height:8px;border-radius:50%;background:var(--acc);box-shadow:0 0 0 5px rgba(6,199,85,.16)}
.hero-title{font-size:54px;font-weight:900;letter-spacing:-1.5px;margin:0 0 20px;line-height:1.12}
.hero-title .hl{background:var(--grad);-webkit-background-clip:text;background-clip:text;-webkit-text-fill-color:transparent}
.hero-sub{font-size:17px;color:var(--fg-soft);max-width:540px;margin:0 0 30px}
.hero-cta{display:flex;flex-direction:column;align-items:flex-start;gap:14px}
.hero-cta .btn-lg{min-width:280px}
.hero-links{display:flex;gap:12px;flex-wrap:wrap}
.hero-links a{font-size:14.5px;color:var(--fg-soft);text-decoration:none;border:1px solid var(--stroke2);padding:9px 16px;border-radius:999px;background:var(--card)}
.hero-links a:hover{color:var(--acc-deep);border-color:var(--acc)}
.hero-note{font-size:13px;color:var(--muted);margin:0}
.plat-chips{display:flex;gap:10px;flex-wrap:wrap;margin-top:22px}
.plat-chips a{display:inline-flex;align-items:center;gap:8px;font-size:13.5px;color:var(--fg-soft);text-decoration:none;background:var(--card);border:1px solid var(--stroke);padding:8px 15px;border-radius:999px;box-shadow:var(--shadow-sm)}
.plat-chips a:hover{color:var(--acc-deep);border-color:rgba(6,199,85,.5)}
.plat-chips svg{color:var(--acc)}

/* 贴图对话卡(招牌沉浸块) */
.chatcard{position:relative;max-width:420px;margin-left:auto;background:var(--card);border:1px solid var(--stroke);border-radius:24px;padding:22px;box-shadow:var(--shadow)}
.chatcard .cc-head{display:flex;align-items:center;gap:11px;margin-bottom:16px;padding-bottom:12px;border-bottom:1px solid var(--stroke)}
.cc-avatar{width:40px;height:40px;flex:none;border-radius:50%;background:var(--grad);display:flex;align-items:center;justify-content:center;color:#fff}
.cc-avatar svg{width:20px;height:20px}
.cc-name{font-size:14.5px;font-weight:700;color:var(--fg);display:block;line-height:1.3}
.cc-status{font-size:11.5px;color:var(--acc-deep)}
.bubble{max-width:82%;padding:10px 14px;border-radius:15px;font-size:13.5px;line-height:1.5;margin-bottom:10px}
.bubble.in{background:var(--card2);color:var(--fg-soft);border-bottom-left-radius:4px}
.bubble.out{background:var(--grad);color:#fff;margin-left:auto;border-bottom-right-radius:4px}
.bubble .t{display:block;font-size:10.5px;opacity:.6;margin-top:4px}
.sticker-row{display:flex;gap:12px;margin:14px 0 6px}
.sticker{width:58px;height:58px;border-radius:18px;display:flex;align-items:center;justify-content:center;box-shadow:var(--shadow-sm)}
.sticker svg{width:36px;height:36px}
.sticker.s1{background:#e6f9ee;color:#06c755}
.sticker.s2{background:#fff3dc;color:#ff9d00}
.sticker.s3{background:#ffe9ec;color:#ff5d7a}
.cc-typing{display:inline-flex;align-items:center;gap:7px;font-size:12px;color:var(--muted)}
.cc-typing .dots{display:inline-flex;gap:3px}
.cc-typing .dots i{width:5px;height:5px;border-radius:50%;background:var(--acc);animation:blink 1.2s infinite}
.cc-typing .dots i:nth-child(2){animation-delay:.2s}
.cc-typing .dots i:nth-child(3){animation-delay:.4s}
@keyframes blink{0%,100%{opacity:.25}50%{opacity:1}}

/* ---------- 数据条 ---------- */
.stats-band{margin-top:-40px;position:relative;z-index:3}
.stat-strip{display:grid;grid-template-columns:repeat(4,1fr);gap:14px}
.stat-card{display:flex;align-items:center;gap:14px;padding:20px 22px;border-radius:var(--r);background:var(--card);border:1px solid var(--stroke);box-shadow:var(--shadow-sm)}
.stat-card .stat-ic{width:46px;height:46px;flex:none;display:flex;align-items:center;justify-content:center;border-radius:13px;font-size:22px;background:var(--acc-soft);color:var(--acc-deep)}
.stat-card.good .stat-ic{background:var(--acc2-soft);color:var(--acc2)}
.stat-num{font-family:var(--font-d);font-weight:700;font-size:19px;color:var(--fg);display:block;line-height:1.3}
.stat-lbl{font-size:13px;color:var(--muted)}

/* ---------- 区块 ---------- */
.section{padding:74px 0}
.section.alt{background:var(--bg2)}
.sec-head{max-width:720px;margin:0 auto 46px;text-align:center}
.sec-head.left{text-align:left;margin-left:0}
.sec-head p{color:var(--muted);margin:0}
.kicker{display:inline-block;font-size:12px;letter-spacing:3px;color:var(--acc-deep);font-weight:700;text-transform:uppercase;margin-bottom:10px}

/* mosaic 画廊 */
.mosaic{display:grid;grid-template-columns:1.6fr 1fr;grid-auto-rows:210px;gap:16px}
.m-item{position:relative;border-radius:var(--r);overflow:hidden;box-shadow:var(--shadow-sm)}
.m-item.big{grid-row:span 2}
.m-item img{width:100%;height:100%;object-fit:cover;transition:.4s}
.m-item:hover img{transform:scale(1.05)}
.m-item .m-cap{position:absolute;left:0;right:0;bottom:0;padding:20px;background:linear-gradient(transparent,rgba(10,40,25,.72));color:#fff}
.m-cap h4{margin:0;color:#fff;font-size:18px}
.m-cap p{margin:0;font-size:13px;color:rgba(255,255,255,.85)}

/* 左右图文 cap-split */
.cap-split{display:grid;grid-template-columns:1fr 1fr;gap:34px;align-items:center}
.cap-split .photo{position:relative;border-radius:var(--rl);overflow:hidden;box-shadow:var(--shadow)}
.cap-split .photo img{width:100%;height:320px;object-fit:cover;display:block}
.cap-split .photo .cap{position:absolute;left:0;right:0;bottom:0;padding:18px;background:linear-gradient(transparent,rgba(10,40,25,.72));color:#fff}
.cap-split .photo .cap h4{margin:0;color:#fff;font-size:17px}
.cap-split .photo .cap p{margin:0;font-size:13px;color:rgba(255,255,255,.85)}
.cap-list{display:flex;flex-direction:column;gap:16px}
.cap-row{display:flex;gap:14px;padding:14px 16px;border-radius:var(--r);background:var(--card);border:1px solid var(--stroke)}
.cap-row .ic{width:44px;height:44px;flex:none;display:flex;align-items:center;justify-content:center;border-radius:12px;background:var(--acc-soft);color:var(--acc-deep);font-size:22px}
.cap-row h4{margin:0 0 3px;font-size:16px}
.cap-row p{margin:0;font-size:14px;color:var(--muted)}

/* band 横条 */
.band{position:relative;padding:84px 0;overflow:hidden;background:var(--grad)}
.band .wrap{position:relative;z-index:2;text-align:center}
.band h2{color:#fff;font-size:36px;margin-bottom:14px}
.band p{color:rgba(255,255,255,.9);max-width:620px;margin:0 auto 26px}
.band .kicker{color:rgba(255,255,255,.85)}
.band-links{display:flex;gap:14px;justify-content:center;flex-wrap:wrap}
.band .btn-ghost{background:rgba(255,255,255,.15);color:#fff;border-color:rgba(255,255,255,.4)}
.band .btn-ghost:hover{background:rgba(255,255,255,.25);color:#fff}

/* steps */
.steps{display:grid;grid-template-columns:repeat(3,1fr);gap:20px}
.steps-h{grid-template-columns:repeat(3,1fr)}
.step{background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);padding:26px 22px;box-shadow:var(--shadow-sm)}
.step .n{width:40px;height:40px;border-radius:50%;background:var(--grad);color:#fff;font-weight:900;font-size:18px;display:flex;align-items:center;justify-content:center;margin-bottom:16px}
.step h4{margin:0 0 8px;font-size:18px}
.step p{margin:0;font-size:14px;color:var(--muted)}

/* 横滑场景卡 */
.sc-strip{display:flex;gap:16px;overflow-x:auto;padding:6px 2px 14px;scroll-snap-type:x mandatory}
.sc-card{flex:0 0 260px;scroll-snap-align:start;border-radius:var(--r);overflow:hidden;background:var(--card);border:1px solid var(--stroke);box-shadow:var(--shadow-sm);text-decoration:none;color:inherit}
.sc-card img{width:100%;height:160px;object-fit:cover;display:block}
.sc-cap{padding:14px 16px}
.sc-cap h4{margin:0 0 4px;font-size:16px;color:var(--fg)}
.sc-cap p{margin:0;font-size:13px;color:var(--muted)}

/* 下载行 */
.dl-rows{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.dl-row{display:flex;align-items:center;gap:16px;padding:18px 20px;border-radius:var(--r);background:var(--card);border:1px solid var(--stroke);text-decoration:none;color:inherit;box-shadow:var(--shadow-sm);transition:.2s}
.dl-row:hover{border-color:var(--acc);transform:translateY(-2px)}
.dl-row .ic{width:46px;height:46px;flex:none;display:flex;align-items:center;justify-content:center;border-radius:13px;background:var(--acc-soft);color:var(--acc-deep);font-size:22px}
.dl-t{flex:1;min-width:0}
.dl-t b{display:block;font-size:16px;color:var(--fg)}
.dl-t span{font-size:13px;color:var(--muted)}
.dl-row .go{color:var(--acc-deep);font-weight:700;font-size:14px}

/* FAQ */
.faq-group{max-width:760px;margin:0 auto}
.faq-group details{background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);margin-bottom:12px;padding:0 20px;box-shadow:var(--shadow-sm)}
.faq-group summary{cursor:pointer;font-weight:700;padding:18px 0;color:var(--fg);font-size:16px;list-style:none}
.faq-group summary::-webkit-details-marker{display:none}
.faq-group summary::after{content:"+";float:right;color:var(--acc);font-size:20px}
.faq-group details[open] summary::after{content:"−"}
.faq-a{padding:0 0 18px;color:var(--fg-soft);font-size:15px}

/* CTA */
.cta-band{text-align:center;padding:56px 30px;border-radius:var(--rl);background:var(--grad);color:#fff;box-shadow:var(--shadow)}
.cta-band h2{color:#fff;font-size:30px;margin-bottom:10px}
.cta-band p{color:rgba(255,255,255,.9);margin-bottom:24px}
.cta-band .btn-primary{background:#fff;color:var(--acc-deep);box-shadow:none}
.cta-band .btn-primary:hover{color:var(--acc-deep)}

/* 表格 */
.table-wrap{overflow-x:auto;border-radius:var(--r);border:1px solid var(--stroke);background:var(--card);box-shadow:var(--shadow-sm)}
.table-wrap table{width:100%;border-collapse:collapse;font-size:15px}
.table-wrap th{background:var(--card2);color:var(--fg);text-align:left;padding:14px 18px;font-weight:700}
.table-wrap td{padding:13px 18px;border-top:1px solid var(--stroke);color:var(--fg-soft)}
.table-wrap tr:hover td{background:var(--bg0)}

/* bento */
.bento{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.bento-card{background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);padding:24px 22px;box-shadow:var(--shadow-sm)}
.bento-card .ic{width:46px;height:46px;display:flex;align-items:center;justify-content:center;border-radius:13px;background:var(--acc-soft);color:var(--acc-deep);font-size:22px;margin-bottom:14px}
.bento-card h3{margin:0 0 8px;font-size:17px}
.bento-card p{margin:0;font-size:14px;color:var(--muted)}

/* 正文 prose(文章/关于) */
.prose{max-width:760px;font-size:16.5px;color:var(--fg-soft)}
.prose h2{font-size:24px;margin:32px 0 14px;color:var(--fg)}
.prose p{margin:0 0 16px}
.prose ul,.prose ol{margin:0 0 18px;padding-left:24px}
.prose li{margin-bottom:6px}
.prose blockquote{margin:0 0 18px;padding:14px 18px;border-left:4px solid var(--acc);background:var(--acc-soft);border-radius:0 12px 12px 0;color:var(--fg-soft)}
.prose figure{margin:0 0 20px}
.prose figure img{border-radius:var(--r);width:100%;box-shadow:var(--shadow-sm)}
.prose figcaption{font-size:13px;color:var(--muted);text-align:center;margin-top:8px}
.tip{background:var(--acc-soft);border:1px solid rgba(6,199,85,.3);color:var(--fg-soft);padding:14px 18px;border-radius:12px;margin:0 0 18px}
.callout{background:var(--acc2-soft);border:1px solid rgba(255,176,32,.4);color:var(--fg-soft);padding:14px 18px;border-radius:12px;margin:0 0 18px}

/* 文章页 */
.article-hero{padding:64px 0 40px;background:radial-gradient(900px 400px at 50% 0%,rgba(6,199,85,.10),transparent 60%),var(--bg0)}
.article-hero h1{font-size:40px;font-weight:900;letter-spacing:-.8px;margin:14px 0 14px}
.article-hero p{color:var(--fg-soft);max-width:720px;font-size:16.5px}
.article-meta{display:flex;gap:22px;flex-wrap:wrap;font-size:13.5px;color:var(--muted);margin-top:16px}
.article-meta span{display:inline-flex;align-items:center;gap:6px}
.article-body{padding:34px 0 70px}
.article-layout{display:grid;grid-template-columns:240px 1fr;gap:44px;max-width:1080px;margin:0 auto;padding:0 22px}
.toc{position:sticky;top:90px;align-self:start;background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);padding:20px;box-shadow:var(--shadow-sm)}
.toc h4{margin:0 0 12px;font-size:14px;letter-spacing:1px;color:var(--muted)}
.toc a{display:block;padding:7px 0;font-size:14px;color:var(--fg-soft);border-bottom:1px dashed var(--stroke)}
.toc a:last-child{border-bottom:none}
.toc a:hover{color:var(--acc-deep)}

/* 相关卡片 */
.rel-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;max-width:1080px;margin:0 auto;padding:0 22px}
.rel-card{display:block;background:var(--card);border:1px solid var(--stroke);border-radius:var(--r);padding:20px;text-decoration:none;color:inherit;box-shadow:var(--shadow-sm);transition:.2s}
.rel-card:hover{border-color:var(--acc);transform:translateY(-2px)}
.rel-card .tag{display:inline-block;font-size:11.5px;letter-spacing:1px;color:var(--acc-deep);background:var(--acc-soft);padding:3px 10px;border-radius:999px;margin-bottom:12px;font-weight:700}
.rel-card h4{margin:0 0 6px;font-size:16px;color:var(--fg)}
.rel-card p{margin:0;font-size:13.5px;color:var(--muted)}
.related{max-width:1080px;margin:44px auto 0;padding:0 22px}
.related .sec-head{max-width:none;margin:0 0 24px}
.related .rel-grid{max-width:none;margin:0;padding:0}

/* 面包屑 */
.breadcrumb{font-size:14px;color:var(--muted);margin-bottom:8px}
.breadcrumb a{color:var(--acc-deep);text-decoration:none}
.breadcrumb a:hover{text-decoration:underline}
.breadcrumb .sep{margin:0 8px;color:var(--muted)}

/* page-hero(内页顶部) */
.page-hero{padding:64px 0 40px;background:radial-gradient(900px 400px at 50% 0%,rgba(6,199,85,.10),transparent 60%),var(--bg0)}
.page-hero h1{font-size:40px;font-weight:900;letter-spacing:-.8px;margin-bottom:14px}
.page-hero p{color:var(--fg-soft);max-width:760px;font-size:16.5px;margin:0}

/* split 左右图文 */
.split{display:grid;grid-template-columns:1fr 1fr;gap:36px;align-items:center}
.split .img{border-radius:var(--r);overflow:hidden;box-shadow:var(--shadow)}
.split .img img{width:100%;height:280px;object-fit:cover;display:block}

/* center-hero(404/search) */
.center-hero{min-height:60vh;display:flex;align-items:center;justify-content:center;text-align:center;padding:60px 22px}
.center-hero h1{font-size:72px;font-weight:900;color:var(--acc);margin-bottom:8px}
.center-hero p{color:var(--muted);margin-bottom:26px}

/* search */
.search-box{display:flex;gap:10px;max-width:520px;margin:0 auto}
.search-box input{flex:1;padding:14px 18px;border:1px solid var(--stroke2);border-radius:999px;font:inherit;font-size:15px;color:var(--fg);background:var(--card)}
.search-box input:focus{outline:none;border-color:var(--acc)}

/* sitemap */
.sitemap-list h2{font-size:20px;margin:28px 0 12px;color:var(--acc-deep)}
.sitemap-list>div{display:flex;flex-direction:column;gap:8px}
.sitemap-list>div a{color:var(--fg-soft);padding:10px 14px;border:1px solid var(--stroke);border-radius:10px;background:var(--card)}
.sitemap-list>div a:hover{color:var(--acc-deep);border-color:var(--acc)}

/* 页脚 */
.mastfoot{background:#123523;color:#dfeee5;padding:60px 0 0;margin-top:0}
.mastfoot a{color:#dfeee5;text-decoration:none}
.mastfoot a:hover{color:#06c755}
.mf-grid{display:grid;grid-template-columns:1.6fr 1fr 1fr 1fr;gap:34px;padding-bottom:44px}
.mf-brand .wordmark{color:#fff}
.mf-brand .wm-name{color:#fff}
.mf-brand p{color:#b8d3c3;font-size:14px;max-width:320px;margin-top:14px}
.mf-col{display:flex;flex-direction:column;gap:10px}
.mf-col h4{color:#fff;font-size:15px;margin:0 0 6px}
.mf-col a{font-size:14px;color:#b8d3c3}
.foot-line{border-top:1px solid rgba(255,255,255,.12);padding:20px 0;text-align:center;color:#9dbbab;font-size:13.5px}

/* 返回顶部 */
.backtop{position:fixed;right:24px;bottom:24px;width:46px;height:46px;border-radius:50%;background:var(--grad);color:#fff;border:none;font-size:20px;cursor:pointer;box-shadow:var(--shadow);opacity:0;visibility:hidden;transition:.25s;z-index:80}
.backtop.show{opacity:1;visibility:visible}

/* 响应式 */
@media(max-width:960px){
  .hero-grid,.cap-split,.split,.article-layout{grid-template-columns:1fr}
  .hero{padding:64px 0}
  .hero-title{font-size:38px}
  .hero-side{justify-content:center}
  .stat-strip,.steps,.steps-h,.bento,.dl-rows,.rel-grid,.mf-grid,.mosaic{grid-template-columns:1fr 1fr}
  .mosaic{grid-auto-rows:170px}
  .toc{position:static}
}
@media(max-width:640px){
  .stat-strip,.steps,.steps-h,.bento,.dl-rows,.rel-grid,.mf-grid,.mosaic{grid-template-columns:1fr}
  .nav-wrap{position:fixed;top:66px;left:0;right:0;background:#fff;flex-direction:column;align-items:stretch;padding:16px;border-bottom:1px solid var(--stroke);display:none}
  .nav-wrap.open{display:flex}
  .nav-toggle{display:block}
  .dd-menu{position:static;box-shadow:none;display:none}
  .dd:hover .dd-menu{display:flex}
  .hero-title{font-size:32px}
  .article-hero h1,.page-hero h1{font-size:30px}
  .chatcard{max-width:100%}
}