/* ============================================================
   zixuan.cool · 站点共享样式
   主色:暮石蓝 #0369a1 / #0ea5e9
   辅色:青绿 #0d9488(成功 / 链接)
   字体:Inter + Noto Sans SC
   ============================================================ */
:root{
  --bg:#fafafa;
  --surface:#ffffff;
  --ink:#0f172a;
  --ink-2:#475569;
  --ink-3:#94a3b8;
  --line:#e2e8f0;
  --line-2:#f1f5f9;
  --brand:#0369a1;
  --brand-2:#0ea5e9;
  --brand-soft:#e0f2fe;
  --accent:#0d9488;
  --accent-soft:#ccfbf1;
  --amber:#b45309;
  --amber-soft:#fef3c7;
  --danger:#dc2626;
  --danger-soft:#fee2e2;

  --r-sm:10px;
  --r-md:14px;
  --r-lg:18px;

  --shadow-1: 0 1px 2px rgba(15,23,42,.04), 0 1px 3px rgba(15,23,42,.05);
  --shadow-2: 0 4px 14px rgba(15,23,42,.07);
  --shadow-3: 0 12px 32px rgba(15,23,42,.12);

  --maxw:1080px;
}

*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{ scroll-behavior: smooth; }
html,body{ height:100%; }
body{
  font-family:"Inter","Noto Sans SC",-apple-system,BlinkMacSystemFont,"Segoe UI",system-ui,"PingFang SC","Microsoft YaHei",sans-serif;
  background:var(--bg);
  color:var(--ink);
  font-size:15px; line-height:1.6;
  -webkit-font-smoothing:antialiased;
  text-rendering: optimizeLegibility;
}
img,svg{display:block;max-width:100%}
a{color:inherit;text-decoration:none}
button{font:inherit;border:0;background:none;cursor:pointer;color:inherit}
input,textarea,select{font:inherit;color:inherit}

/* 统一的容器 */
.shell{ max-width: var(--maxw); margin: 0 auto; padding: 0 24px; }

/* ----- topbar ----- */
.topbar{ background:var(--surface); border-bottom:1px solid var(--line); }
.topbar-inner{
  display:flex; align-items:center; justify-content:space-between;
  height: 60px;
}
.brand{ display:flex; align-items:center; gap:10px; font-weight:700;}
.brand-mark{
  width:32px; height:32px; border-radius:8px;
  background: linear-gradient(135deg,#0ea5e9,#0369a1);
  display:grid; place-items:center; color:#fff; font-weight:800; font-size:14px;
  letter-spacing:-0.5px;
}
.brand-name{ font-size:16px;}
.brand-sub{ font-size:11px; color: var(--ink-3); margin-top:1px; font-weight:400; letter-spacing:0.05em; text-transform:uppercase;}

.topbar-nav{ display:flex; gap:4px;}
.topbar-nav a{
  padding: 7px 14px; border-radius:8px; font-size:13px; color: var(--ink-2);
  font-weight:500;
}
.topbar-nav a:hover{ color: var(--brand);}
.topbar-nav a.active{ background: var(--brand-soft); color: var(--brand); font-weight:600;}

/* ----- cards ----- */
.card{
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--r-md);
  padding: 22px;
  display: flex; flex-direction: column;
  transition: border-color .12s ease, transform .12s ease;
}
.card:hover{ border-color: var(--brand-2); transform: translateY(-2px); }
.card-head{ display:flex; align-items:center; gap:10px; margin-bottom: 12px;}
.card-icon{
  width: 36px; height:36px; border-radius:9px;
  background: var(--brand-soft); color: var(--brand);
  display:grid; place-items:center;
}
.card-icon svg{ width:20px; height:20px; }
.card-icon.accent{ background: var(--accent-soft); color: var(--accent);}
.card-icon.amber{ background: var(--amber-soft); color: var(--amber);}
.card-title{ font-size: 16px; font-weight: 600; color: var(--ink);}
.card-desc{ font-size: 14px; color: var(--ink-2); flex:1; }
.card-meta{
  display:flex; justify-content:space-between; align-items:center;
  margin-top: 16px; padding-top: 14px;
  border-top: 1px solid var(--line-2);
  font-size: 12px;
}
.tag{
  display:inline-block; padding: 2px 8px; border-radius:999px;
  background: var(--line-2); color: var(--ink-2);
  font-size: 11px; font-weight: 600;
}
.tag.brand{ background: var(--brand-soft); color: var(--brand);}
.tag.accent{ background: var(--accent-soft); color: var(--accent);}
.tag.amber{ background: var(--amber-soft); color: var(--amber);}
.card-arrow{ color: var(--ink-3); transition: color .12s ease, transform .12s ease;}
.card:hover .card-arrow{ color: var(--brand); transform: translateX(2px); }

/* ----- footer ----- */
.site-footer{
  background: var(--surface); border-top: 1px solid var(--line);
  padding: 22px 0; margin-top: 40px;
}
.footer-row{
  display:flex; justify-content:space-between; align-items:center; gap:16px; flex-wrap:wrap;
  font-size: 13px; color: var(--ink-2);
}
.footer-row a:hover{ color: var(--brand);}

/* ----- responsive ----- */
@media (max-width: 720px){
  .shell{ padding: 0 16px; }
  .topbar-nav{ display:none; }
  .topbar-inner{ height: 52px; }
  .brand-sub{ display:none; }
}

/* ----- utilities ----- */
.btn{
  display:inline-flex; align-items:center; justify-content:center; gap:6px;
  padding: 10px 16px; border-radius: 10px;
  font-weight: 600; font-size: 14px;
  background: var(--brand); color:#fff;
  transition: background .12s ease;
}
.btn:hover{ background: var(--brand-2); }

.btn-ghost{
  background: transparent;
  border:1px solid var(--line);
  color: var(--ink);
}
.btn-ghost:hover{ background: var(--line-2); border-color: var(--ink-3);}

.sr-only{ position:absolute; width:1px; height:1px; padding:0; margin:-1px; overflow:hidden; clip:rect(0,0,0,0); white-space:nowrap; border:0;}

/* dark mode (auto) */
@media (prefers-color-scheme: dark){
  :root{
    --bg:#0b1220;
    --surface:#111827;
    --ink:#f1f5f9;
    --ink-2:#cbd5e1;
    --ink-3:#64748b;
    --line:#1f2937;
    --line-2:#1e293b;
    --brand:#38bdf8;
    --brand-2:#7dd3fc;
    --brand-soft:#0c4a6e;
    --accent:#2dd4bf;
    --accent-soft:#042f2e;
    --amber:#fbbf24;
    --amber-soft:#451a03;
    --danger:#f87171;
    --danger-soft:#450a0a;
  }
  .brand-mark{ background: linear-gradient(135deg,#38bdf8,#0ea5e9);}
  .btn{ color: #0b1220; }
  .btn-ghost{ color: var(--ink); }
  .topbar-nav a.active{ color:#7dd3fc;}
}