/* ========== AI 技术免费分享站 · Mobile-First 样式 ========== */
:root{
  --brand:#2b6cff;
  --brand-2:#0ea5e9;
  --ink:#1a2233;
  --ink-2:#5b667c;
  --line:#e6ebf2;
  --bg:#f5f7fa;
  --card:#fff;
  --radius:14px;
  --shadow:0 2px 12px rgba(24,39,75,.06);
  --wrap:1080px;
}
*{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html{-webkit-text-size-adjust:100%}
body{
  font-family:system-ui,-apple-system,"Segoe UI","Microsoft YaHei",sans-serif;
  background:var(--bg);color:var(--ink);line-height:1.75;font-size:16px;
  overflow-x:hidden;
}
p,li,dd,td,h1,h2,h3{overflow-wrap:anywhere}
img,svg,video{max-width:100%}
a{color:var(--brand);text-decoration:none}
img{max-width:100%;display:block}
.wrap{width:100%;max-width:var(--wrap);margin:0 auto;padding:0 16px}

/* ---------- 顶栏 ---------- */
.site-header{
  background:linear-gradient(135deg,#2c3e50,#2b6cff);
  color:#fff;position:sticky;top:0;z-index:50;box-shadow:0 1px 10px rgba(0,0,0,.12)
}
.header-inner{display:flex;align-items:center;justify-content:space-between;height:56px}
.brand{display:flex;align-items:center;gap:8px;color:#fff;font-weight:700;font-size:16px}
.brand-mark{
  width:28px;height:28px;border-radius:8px;background:rgba(255,255,255,.22);
  display:grid;place-items:center;font-size:13px;letter-spacing:.5px
}
.brand-text{max-width:56vw;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}
.nav{display:flex;gap:18px}
.nav a{color:rgba(255,255,255,.82);font-size:15px}
.nav a.on{color:#fff;font-weight:600}
.nav a.on::after{content:"";display:block;height:2px;background:#fff;border-radius:2px;margin-top:2px}

/* ---------- 主体 ---------- */
.main{padding-top:20px;padding-bottom:48px;min-height:60vh}
.flash{background:#fff7e6;border:1px solid #ffd591;color:#8c5a00;padding:10px 14px;border-radius:10px;margin-bottom:16px}

/* ---------- 首页 hero ---------- */
.hero{
  background:linear-gradient(135deg,#2c3e50,#2b6cff);color:#fff;border-radius:var(--radius);
  padding:28px 20px;margin-bottom:22px
}
.hero h1{font-size:23px;line-height:1.4;margin-bottom:8px}
.hero p{color:rgba(255,255,255,.86);font-size:14px}
.hero-tags{display:flex;flex-wrap:wrap;gap:8px;margin-top:16px}
.hero-tags span{background:rgba(255,255,255,.16);padding:4px 10px;border-radius:20px;font-size:12px}

/* ---------- 区块标题 ---------- */
.sec-title{display:flex;align-items:center;justify-content:space-between;margin:26px 0 14px}
.sec-title h1,.sec-title h2{font-size:18px}
.sec-title a{font-size:13px;color:var(--ink-2)}

/* ---------- 卡片列表 ---------- */
.grid{display:grid;gap:14px;grid-template-columns:1fr}
@media(min-width:680px){.grid{grid-template-columns:1fr 1fr}}
@media(min-width:960px){.grid{grid-template-columns:repeat(3,1fr)}}

.card{
  background:var(--card);border-radius:var(--radius);box-shadow:var(--shadow);
  overflow:hidden;display:flex;flex-direction:column;transition:transform .16s,box-shadow .16s
}
.card:active{transform:scale(.99)}
@media(hover:hover){.card:hover{transform:translateY(-3px);box-shadow:0 8px 22px rgba(24,39,75,.1)}}
.card-cover{
  height:132px;background:linear-gradient(135deg,#eef3ff,#dbe7ff);
  display:grid;place-items:center;color:#8ea6d8;font-size:13px;font-weight:600
}
.card-body{padding:14px;display:flex;flex-direction:column;gap:8px;flex:1}
.card-title{font-size:16px;font-weight:600;line-height:1.45}
.card-sum{font-size:13px;color:var(--ink-2);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}
.card-meta{display:flex;flex-wrap:wrap;gap:6px;margin-top:auto;padding-top:6px}
.chip{font-size:11px;background:#eef3ff;color:#3b5bdb;padding:2px 8px;border-radius:20px}
.chip.gray{background:#f0f2f5;color:var(--ink-2)}

/* ---------- 分类条 ---------- */
.cats{display:flex;gap:8px;overflow-x:auto;padding:4px 0 10px;-webkit-overflow-scrolling:touch}
.cats::-webkit-scrollbar{display:none}
.cats a{
  flex:0 0 auto;background:#fff;border:1px solid var(--line);border-radius:20px;
  padding:6px 14px;font-size:13px;color:var(--ink-2)
}
.cats a.on{background:var(--brand);border-color:var(--brand);color:#fff}

/* ---------- 详情页 ---------- */
.detail-head{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;margin-bottom:16px}
.detail-head h1{font-size:21px;line-height:1.4;margin-bottom:10px}
.detail-tags{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:12px}
.detail-sum{color:var(--ink-2);font-size:14px}
.info-list{border-top:1px solid var(--line);margin-top:14px;padding-top:12px;font-size:13px}
.info-list div{display:flex;gap:10px;padding:4px 0}
.info-list dt{color:var(--ink-2);flex:0 0 76px}
.info-list dd{flex:1 1 auto;min-width:0;word-break:break-all;overflow-wrap:anywhere}

/* ---------- 下载区（变现核心） ---------- */
.dl-box{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;margin-bottom:16px}
.dl-title{font-size:15px;font-weight:600;margin-bottom:12px;display:flex;align-items:center;gap:8px}
.dl-title::before{content:"";width:4px;height:16px;background:var(--brand);border-radius:3px}

.btn-dl{
  display:flex;align-items:center;justify-content:center;gap:8px;
  width:100%;padding:16px;border-radius:12px;font-size:17px;font-weight:700;color:#fff;
  background:linear-gradient(135deg,#2b6cff,#0ea5e9);
  box-shadow:0 6px 18px rgba(43,108,255,.28)
}
.btn-dl:active{transform:scale(.99)}
.dl-sub{text-align:center;font-size:12px;color:var(--ink-2);margin-top:10px}
.dl-free{display:flex;justify-content:center;gap:14px;flex-wrap:wrap;font-size:12px;color:var(--ink-2);margin-top:10px}

/* PC 端扫码桥接：默认隐藏，JS 判定为 PC 才显示 */
.dl-pc{display:none}
body.is-pc .dl-pc{display:block}
body.is-pc .dl-mobile{display:none}
.qr-flex{display:flex;align-items:center;gap:18px}
.qr-img{width:132px;height:132px;flex:0 0 132px;border:1px solid var(--line);border-radius:10px;padding:6px;background:#fff}
.qr-txt strong{display:block;font-size:16px;margin-bottom:6px}
.qr-txt p{font-size:13px;color:var(--ink-2);margin-bottom:10px}
.qr-txt .alt{font-size:12px;color:#9aa5b8}

/* Netdisk 提示块 */
.nd-note{background:#f0f7ff;border:1px solid #cfe2ff;border-radius:10px;padding:12px;font-size:13px;color:#2b4a7d;margin-top:12px}

/* ---------- 正文 ---------- */
.article{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:18px}
.article h2{font-size:18px;margin:22px 0 10px;padding-left:10px;border-left:4px solid var(--brand)}
.article h3{font-size:16px;margin:18px 0 8px}
.article p{margin:10px 0;color:#2c3547}
.article ul,.article ol{margin:10px 0 10px 22px;color:#2c3547}
.article li{margin:4px 0}
.article code{background:#f3f5f9;padding:2px 6px;border-radius:5px;font-size:13px;color:#c7254e}
.article pre{background:#1e2430;color:#e6edf3;padding:14px;border-radius:10px;overflow-x:auto;margin:12px 0}
.article pre code{background:none;color:inherit;padding:0}
.article blockquote{border-left:3px solid var(--line);padding-left:12px;color:var(--ink-2);margin:12px 0}
.article table{width:100%;border-collapse:collapse;margin:12px 0;font-size:13px;display:block;overflow-x:auto}
.article th,.article td{border:1px solid var(--line);padding:8px 10px;text-align:left}
.article th{background:#f7f9fc}

/* ---------- 页脚（备案合规） ---------- */
.site-footer{background:#1e2430;color:#9aa5b8;padding:24px 0;font-size:13px}
.foot-links{margin-bottom:8px}
.foot-links a{color:#c3ccdb}
.foot-note{font-size:12px;color:#6b7688;margin-bottom:10px;line-height:1.7}
.foot-beian{font-size:12px;color:#8b96a8;display:flex;gap:8px;align-items:center;flex-wrap:wrap}
.foot-beian a{color:#a8b3c4}
.foot-beian .sep{color:#3a4356}

/* ---------- 站内搜索 ---------- */
.searchbar{display:flex;gap:8px;padding:0 0 12px}
.search-h1{font-size:20px;margin:4px 0 14px}
.searchbar input[type=search]{
  flex:1 1 auto;min-width:0;border:1px solid rgba(255,255,255,.28);background:rgba(255,255,255,.14);
  color:#fff;border-radius:10px;padding:9px 13px;font-size:15px;font-family:inherit;outline:none
}
.searchbar input[type=search]::placeholder{color:rgba(255,255,255,.62)}
.searchbar input[type=search]:focus{background:rgba(255,255,255,.22);border-color:rgba(255,255,255,.5)}
.searchbar button{
  flex:0 0 auto;border:0;border-radius:10px;padding:9px 18px;cursor:pointer;
  background:#fff;color:var(--brand);font-size:15px;font-weight:600;font-family:inherit
}
.search-head{margin-bottom:6px}
.search-head .searchbar{padding-bottom:10px}
.search-head .searchbar input[type=search]{
  border:1px solid var(--line);background:#fff;color:var(--ink);box-shadow:var(--shadow)
}
.search-head .searchbar input[type=search]::placeholder{color:#9aa5b8}
.search-head .searchbar input[type=search]:focus{border-color:var(--brand);background:#fff}
.search-head .searchbar button{background:var(--brand);color:#fff}
.search-stat{font-size:14px;color:var(--ink-2);margin:4px 0 6px}
.search-tips{font-size:13px;color:#9aa5b8;margin-top:10px}

.foot-services{display:flex;flex-wrap:wrap;gap:8px 16px;margin:10px 0}
.foot-services a{color:#c3ccdb}

/* ---------- 提示页 ---------- */
.empty{text-align:center;padding:56px 20px;color:var(--ink-2)}

/* ---------- 后台 ---------- */
.adm-bar{background:#1e2430;color:#fff;padding:0}
.adm-bar .wrap{display:flex;align-items:center;gap:16px;height:50px;flex-wrap:nowrap;overflow-x:auto}
.adm-bar a{color:#b9c4d6;font-size:14px;white-space:nowrap}
.adm-bar a.on,.adm-bar a:hover{color:#fff}
.adm-bar .sp{margin-left:auto}
.adm-quick{border-top:1px solid rgba(255,255,255,.12);padding-top:7px;padding-bottom:7px;gap:14px;height:auto;flex-wrap:wrap}
.adm-quick-label{color:#7c8798;font-size:12px}
.adm-quick a{font-size:13px;color:#8fd0ff}
.adm-quick a:hover{color:#fff}
.adm-card{background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;margin-bottom:16px}
.adm-stats{display:grid;grid-template-columns:repeat(2,1fr);gap:12px}
@media(min-width:680px){.adm-stats{grid-template-columns:repeat(4,1fr)}}
.stat{background:linear-gradient(135deg,#f7f9ff,#eef3ff);border-radius:12px;padding:14px}
.stat b{display:block;font-size:24px;color:var(--brand)}
.stat span{font-size:12px;color:var(--ink-2)}

.tbl{width:100%;border-collapse:collapse;font-size:14px}
.tbl th,.tbl td{border-bottom:1px solid var(--line);padding:10px 8px;text-align:left}
.tbl th{color:var(--ink-2);font-weight:600;font-size:13px;background:#f7f9fc}
.tbl-wrap{overflow-x:auto}

.field{margin-bottom:14px}
.field label{display:block;font-size:13px;font-weight:600;margin-bottom:6px;color:#2c3547}
.field input[type=text],.field input[type=password],.field input[type=number],
.field select,.field textarea{
  width:100%;border:1px solid var(--line);border-radius:10px;padding:10px 12px;
  font-size:15px;font-family:inherit;background:#fff;color:var(--ink)
}
.field textarea{min-height:200px;line-height:1.7;font-family:ui-monospace,Consolas,monospace;font-size:13px}
.field .hint{font-size:12px;color:var(--ink-2);margin-top:5px}
.field-row{display:grid;gap:12px;grid-template-columns:1fr}
@media(min-width:680px){.field-row{grid-template-columns:1fr 1fr}}
.btn{
  display:inline-block;padding:10px 20px;border-radius:10px;border:0;cursor:pointer;
  font-size:15px;font-weight:600;background:var(--brand);color:#fff
}
.btn.ghost{background:#eef2f8;color:#33415c}
.btn.danger{background:#ff4d4f}
.btn.sm{padding:6px 12px;font-size:13px;border-radius:8px}
.btn-row{display:flex;gap:10px;flex-wrap:wrap;margin-top:6px}
.switch{display:flex;align-items:center;gap:8px;font-size:14px}
.login-box{max-width:360px;margin:40px auto;background:#fff;border-radius:var(--radius);box-shadow:var(--shadow);padding:24px}