:root{
  --bg:#ffffff; --fg:#0f172a; --muted:#64748b; --line:#e5e7eb;
  --brand:#2563eb; --brand2:#7c3aed; --soft:#f6f8fc; --card:#ffffff;
  --ink:#0b1020; --radius:14px; --shadow:0 1px 2px rgba(15,23,42,.06),0 8px 24px rgba(15,23,42,.06);
}
*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI",Roboto,"Helvetica Neue","PingFang SC","Microsoft YaHei",sans-serif;color:var(--fg);background:var(--bg);line-height:1.65;-webkit-font-smoothing:antialiased}
a{color:inherit;text-decoration:none}
h1,h2,h3{line-height:1.25;margin:0 0 .5em}
h1{font-size:clamp(1.9rem,4vw,3rem);letter-spacing:-.02em}
h2{font-size:clamp(1.4rem,2.6vw,2rem);letter-spacing:-.01em}
p{margin:0 0 1em}
.wrap{max-width:1120px;margin:0 auto;padding:0 22px}
.narrow{max-width:760px}
.center{text-align:center}
.muted{color:var(--muted)}
.small{font-size:.85rem}
.ic{width:1.15em;height:1.15em;vertical-align:-.2em;flex:0 0 auto}

/* header */
.site-header{position:sticky;top:0;z-index:50;background:rgba(255,255,255,.85);backdrop-filter:blur(10px);border-bottom:1px solid var(--line)}
.header-inner{display:flex;align-items:center;gap:22px;height:64px}
.brand{display:inline-flex;align-items:center;gap:.5em;font-weight:800;font-size:1.15rem;letter-spacing:-.01em}
.brand-dot{width:.7em;height:.7em;border-radius:50%;background:linear-gradient(135deg,var(--brand),var(--brand2));box-shadow:0 0 0 4px rgba(37,99,235,.12)}
.nav{display:flex;gap:22px;margin-left:auto;font-weight:500}
.nav a{color:#334155}
.nav a:hover{color:var(--brand)}
.header-actions{display:flex;align-items:center;gap:14px}
.lang{font-size:.9rem;color:var(--muted);border:1px solid var(--line);border-radius:999px;padding:.25em .8em}
.lang:hover{border-color:var(--brand);color:var(--brand)}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:.5em;background:var(--brand);color:#fff;border-radius:999px;padding:.6em 1.15em;font-weight:600;border:1px solid transparent;cursor:pointer;transition:.15s}
.btn:hover{background:#1d4ed8}
.btn-sm{padding:.42em .9em;font-size:.9rem}
.btn-lg{padding:.8em 1.6em;font-size:1.05rem;box-shadow:0 6px 18px rgba(37,99,235,.28)}
.btn-ghost{background:transparent;color:var(--fg);border-color:var(--line)}
.btn-ghost:hover{background:var(--soft)}

/* hero */
.hero{position:relative;overflow:hidden;background:
  radial-gradient(1200px 500px at 80% -10%,rgba(124,58,237,.12),transparent 60%),
  radial-gradient(900px 400px at 0% 0%,rgba(37,99,235,.12),transparent 55%),var(--soft)}
.hero-inner{display:grid;grid-template-columns:1.05fr .95fr;gap:40px;align-items:center;padding:64px 22px 72px}
.badge{display:inline-flex;align-items:center;gap:.5em;background:#fff;border:1px solid var(--line);color:var(--brand);border-radius:999px;padding:.35em .9em;font-size:.85rem;font-weight:600;box-shadow:var(--shadow)}
.lead{font-size:1.12rem;color:#334155}
.cta{display:flex;gap:14px;margin:22px 0}
.meta-row{display:flex;flex-wrap:wrap;gap:8px 22px;list-style:none;padding:0;margin:0;color:var(--muted);font-size:.9rem}
.hero-shot img{width:100%;height:auto;border-radius:var(--radius);border:1px solid var(--line);box-shadow:0 24px 60px rgba(15,23,42,.18)}

/* sections */
.section{padding:64px 0}
.band{background:var(--ink);color:#e5e7eb;padding:56px 0;border-radius:22px;margin:8px 0}
.band h2{text-align:center;color:#fff}
.band .card{background:rgba(255,255,255,.05);border:1px solid rgba(255,255,255,.1);color:#e5e7eb}
.band .card p{color:#c3cad8}
.band .card-ic{background:rgba(255,255,255,.1);color:#fff}

.cards{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin-top:28px}
.card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:22px;box-shadow:var(--shadow)}
.card h3{font-size:1.1rem}
.card p{margin:0;color:#475569}
.card-ic{display:inline-flex;align-items:center;justify-content:center;width:42px;height:42px;border-radius:11px;background:linear-gradient(135deg,rgba(37,99,235,.14),rgba(124,58,237,.14));color:var(--brand);margin-bottom:14px;font-size:1.3rem}

/* requirements */
.req-inner{max-width:820px}
.req-list{list-style:none;padding:0;margin:0;display:grid;grid-template-columns:1fr 1fr;gap:12px 24px}
.req-list li{display:flex;gap:.7em;align-items:flex-start;color:#334155}
.req-list .ic{color:var(--brand);margin-top:.25em;font-size:1.25rem}

/* download / cta */
.dl-cta{background:var(--soft);border-radius:22px}
.dl-item{margin:20px 0}
.dl-head{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.dl-meta{display:grid;grid-template-columns:auto 1fr;gap:4px 18px;margin:14px 0 0;font-size:.92rem}
.dl-meta dt{color:var(--muted)}
.dl-meta dd{margin:0;font-variant-numeric:tabular-nums}
.hash{font-family:ui-monospace,Menlo,Consolas,monospace;word-break:break-all;font-size:.82rem}
.dl-notes{margin-top:14px;padding-top:12px;border-top:1px dashed var(--line)}
.tag{display:inline-block;font-size:.75rem;background:var(--soft);border:1px solid var(--line);border-radius:999px;padding:.1em .6em;color:var(--muted);font-weight:600;vertical-align:middle}
.note{margin-top:22px;background:#fffbeb;border:1px solid #fde68a;color:#92400e;border-radius:10px;padding:12px 16px;font-size:.9rem}

/* guestbook */
.gb-form{margin:22px 0 34px;display:flex;flex-direction:column;gap:14px}
.gb-form .row{display:grid;grid-template-columns:1fr 1fr;gap:14px}
.gb-form label{display:flex;flex-direction:column;gap:.35em;font-size:.9rem;font-weight:600;color:#334155}
.gb-form input,.gb-form textarea{font:inherit;font-weight:400;border:1px solid var(--line);border-radius:10px;padding:.6em .75em;background:#fff;color:var(--fg)}
.gb-form input:focus,.gb-form textarea:focus{outline:2px solid rgba(37,99,235,.35);border-color:var(--brand)}
.hp{position:absolute;left:-9999px;width:1px;height:1px;opacity:0}
.form-foot{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap}
.flash{border-radius:10px;padding:10px 16px;margin:0 0 16px;font-size:.92rem;display:flex;gap:.5em;align-items:center}
.flash.ok{background:#ecfdf5;border:1px solid #a7f3d0;color:#065f46}
.flash.err{background:#fef2f2;border:1px solid #fecaca;color:#991b1b}
.comments{list-style:none;padding:0;margin:0;display:flex;flex-direction:column;gap:14px}
.comment{margin:0}
.c-head{display:flex;align-items:center;gap:10px;margin-bottom:6px}
.c-author{font-weight:700}
.c-geo{font-size:.72rem;background:var(--soft);border:1px solid var(--line);border-radius:6px;padding:.05em .45em;color:var(--muted)}
.c-head time{margin-left:auto}
.c-body{margin:0;white-space:pre-wrap;word-break:break-word}
.c-reply{margin-top:12px;padding:10px 14px;background:var(--soft);border-left:3px solid var(--brand);border-radius:8px}
.c-reply p{margin:.3em 0 0}

/* footer */
.site-footer{background:var(--ink);color:#c3cad8;padding:40px 0 26px;margin-top:40px}
.footer-inner{display:flex;justify-content:space-between;gap:24px;flex-wrap:wrap}
.footer-inner .brand{color:#fff}
.site-footer .muted{color:#8b93a7}
.foot-links{display:flex;gap:20px;flex-wrap:wrap}
.foot-links a:hover{color:#fff}
.foot-bottom{display:flex;justify-content:space-between;gap:16px;flex-wrap:wrap;margin-top:26px;padding-top:20px;border-top:1px solid rgba(255,255,255,.1);font-size:.85rem}
.foot-bottom a{text-decoration:underline}

@media (max-width:820px){
  .hero-inner{grid-template-columns:1fr;padding:40px 22px 48px}
  .hero-shot{order:-1}
  .nav{display:none}
  .req-list{grid-template-columns:1fr}
  .gb-form .row{grid-template-columns:1fr}
}

/* announce + admin */
.announce{background:#eef2ff;border-bottom:1px solid #c7d2fe;color:#3730a3;text-align:center;padding:8px 22px;font-size:.9rem}
.admin{background:#f1f3f7}
.admin-header{position:sticky;top:0;z-index:40;background:#0b1020;color:#e5e7eb}
.admin-inner{display:flex;align-items:center;gap:20px;height:56px}
.admin-inner .brand{color:#fff}
.admin-nav{display:flex;gap:16px;margin-left:auto}
.admin-nav a{color:#c3cad8;font-size:.92rem}
.admin-nav a:hover{color:#fff}
.admin-main{padding:26px 22px 60px}
.admin .card{margin-bottom:16px}
.kpis{display:grid;grid-template-columns:repeat(auto-fit,minmax(140px,1fr));gap:12px;margin:18px 0}
.kpi{background:#fff;border:1px solid var(--line);border-radius:12px;padding:14px 16px;display:flex;flex-direction:column;gap:4px}
.kpi span{color:var(--muted);font-size:.82rem}
.kpi b{font-size:1.5rem}
.two-col{display:grid;grid-template-columns:1fr 1fr;gap:16px}
.tbl{width:100%;border-collapse:collapse;font-size:.88rem}
.tbl td,.tbl th{text-align:left;padding:6px 8px;border-bottom:1px solid var(--line);vertical-align:top}
.tbl th{color:var(--muted);font-weight:600}
.wide{min-width:760px}
.scroll-x{overflow-x:auto}
.ua{max-width:320px;word-break:break-all;color:var(--muted);font-size:.78rem}
.login-box{max-width:380px;margin:8vh auto 0}
.btn-danger{background:#dc2626}
.btn-danger:hover{background:#b91c1c}
.ops,.ops-cell{display:flex;gap:8px;align-items:flex-start;flex-wrap:wrap}
/* 软删除的留言：整行变淡 + 内容划线，避免管理员误以为「删除没生效」。 */
.tbl tr.row-deleted td{background:#fef2f2;color:#94a3b8}
.tbl tr.row-deleted .c-body{text-decoration:line-through}
.tag-del{display:inline-block;font-size:.72rem;background:#fee2e2;border:1px solid #fecaca;color:#991b1b;border-radius:6px;padding:.05em .45em}
/* 「退出」按钮：.btn-ghost 默认文字是深色（--fg），放在深色顶部栏上等于看不见，
   这里给头部内的 ghost 按钮单独一套高对比配色。 */
.admin-header form{margin:0;display:flex;align-items:center}
.admin-header .btn-ghost{background:#2a3350;color:#e5e7eb;border-color:#4b5675}
.admin-header .btn-ghost:hover{background:#3a466b;color:#fff}
/* 自带确认框：不依赖 window.confirm。浏览器可以永久屏蔽原生对话框（Chrome 的
   「阻止此页面创建其他对话框」），一旦被屏蔽原生确认直接返回 false，删除就变成
   「点了没反应」，所以确认框由 admin.js 自己画。 */
.cf-mask{position:fixed;inset:0;z-index:90;display:flex;align-items:center;justify-content:center;padding:22px;background:rgba(11,16,32,.55)}
.cf-mask[hidden]{display:none}
.cf-box{width:100%;max-width:440px;background:#fff;color:var(--fg);border-radius:14px;box-shadow:0 24px 60px rgba(11,16,32,.35);padding:20px 22px}
.cf-box h3{margin:0 0 8px;font-size:1.05rem}
.cf-box p{margin:0;color:#334155;font-size:.94rem;line-height:1.65}
.cf-actions{display:flex;justify-content:flex-end;gap:10px;margin-top:18px}
/* 留言列表工具条：「已删」记录默认不列出，删完那一行立刻消失。 */
.cmt-bar{display:flex;align-items:center;gap:12px;flex-wrap:wrap;margin:0 0 12px}
.reply-form{display:flex;flex-direction:column;gap:6px}
.reply-form textarea{font:inherit;border:1px solid var(--line);border-radius:8px;padding:.4em .5em}
@media(max-width:820px){.two-col{grid-template-columns:1fr}.admin-nav{display:none}}