:root {
  --bg: #f5f6fa;
  --bg-elev: #ffffff;
  --bg-soft: #eef0f6;
  --text: #1a1d29;
  --text-soft: #5b6072;
  --text-mut: #9498a8;
  --border: #e6e8f0;
  --brand: #6c5ce7;
  --brand-2: #00b894;
  --brand-grad: linear-gradient(135deg, #6c5ce7 0%, #a66bff 50%, #00b8d4 100%);
  --shadow-sm: 0 1px 2px rgba(20,24,40,.06), 0 2px 8px rgba(20,24,40,.04);
  --shadow-md: 0 6px 24px rgba(76,80,160,.12);
  --radius: 16px;
  --radius-sm: 12px;
  --sidebar-w: 248px;
  --topbar-h: 64px;
  --font: "PingFang SC", "Microsoft YaHei", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
}

[data-theme="dark"] {
  --bg: #0f1117;
  --bg-elev: #181b24;
  --bg-soft: #1f2330;
  --text: #e8eaf2;
  --text-soft: #a8adc0;
  --text-mut: #6b7185;
  --border: #272b39;
  --shadow-sm: 0 1px 2px rgba(0,0,0,.3);
  --shadow-md: 0 8px 28px rgba(0,0,0,.45);
}

* { box-sizing: border-box; margin: 0; padding: 0; }

html { scroll-behavior: smooth; }

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--text);
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
  display: flex;
  min-height: 100vh;
}

a { color: inherit; text-decoration: none; }

/* ===== Sidebar ===== */
.sidebar {
  width: var(--sidebar-w);
  flex-shrink: 0;
  background: var(--bg-elev);
  border-right: 1px solid var(--border);
  position: fixed;
  top: 0; left: 0; bottom: 0;
  display: flex;
  flex-direction: column;
  z-index: 40;
}

.sidebar-brand {
  height: var(--topbar-h);
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 0 22px;
  font-size: 20px;
  font-weight: 800;
  letter-spacing: .5px;
  border-bottom: 1px solid var(--border);
}
.brand-logo {
  width: 30px; height: 30px;
  display: grid; place-items: center;
  background: var(--brand-grad);
  color: #fff; border-radius: 9px;
  font-size: 15px;
  box-shadow: var(--shadow-sm);
}
.brand-name em { font-style: normal; color: var(--brand); }
[data-theme="dark"] .brand-name em { color: #a66bff; }

.cat-nav {
  flex: 1;
  overflow-y: auto;
  padding: 14px 12px;
  display: flex;
  flex-direction: column;
  gap: 2px;
}
.cat-nav::-webkit-scrollbar { width: 6px; }
.cat-nav::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

.cat-link {
  display: flex;
  align-items: center;
  gap: 11px;
  padding: 9px 14px;
  border-radius: 10px;
  color: var(--text-soft);
  font-size: 14.5px;
  font-weight: 500;
  cursor: pointer;
  transition: background .15s, color .15s;
  white-space: nowrap;
}
.cat-link:hover { background: var(--bg-soft); color: var(--text); }
.cat-link.active {
  background: var(--brand);
  color: #fff;
  box-shadow: var(--shadow-sm);
}
.cat-link.active .cat-count { background: rgba(255,255,255,.22); color:#fff; }
.cat-emoji { font-size: 16px; width: 20px; text-align: center; }
.cat-label { flex: 1; overflow: hidden; text-overflow: ellipsis; }
.cat-count {
  font-size: 11.5px;
  background: var(--bg-soft);
  color: var(--text-mut);
  padding: 1px 8px;
  border-radius: 20px;
  font-weight: 600;
}

.sidebar-foot {
  padding: 14px 22px;
  font-size: 12px;
  color: var(--text-mut);
  border-top: 1px solid var(--border);
}

/* ===== Main ===== */
.main {
  flex: 1;
  margin-left: var(--sidebar-w);
  min-width: 0;
}

.topbar {
  position: sticky;
  top: 0;
  height: var(--topbar-h);
  background: color-mix(in srgb, var(--bg-elev) 88%, transparent);
  backdrop-filter: saturate(180%) blur(14px);
  border-bottom: 1px solid var(--border);
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 0 26px;
  z-index: 30;
}

.search-wrap {
  flex: 1;
  max-width: 620px;
  position: relative;
  display: flex;
  align-items: center;
}
.search-icon {
  position: absolute; left: 15px;
  color: var(--text-mut);
}
#searchInput {
  width: 100%;
  height: 42px;
  padding: 0 44px 0 44px;
  border: 1.5px solid var(--border);
  background: var(--bg-soft);
  border-radius: 12px;
  font-size: 14.5px;
  color: var(--text);
  font-family: inherit;
  transition: border-color .15s, background .15s;
}
#searchInput:focus {
  outline: none;
  border-color: var(--brand);
  background: var(--bg-elev);
}
.search-kbd {
  position: absolute; right: 14px;
  font-size: 12px; color: var(--text-mut);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 1px 7px;
  background: var(--bg-elev);
}

.topbar-actions { display: flex; gap: 8px; }
.icon-btn {
  width: 42px; height: 42px;
  display: grid; place-items: center;
  border: 1.5px solid var(--border);
  background: var(--bg-soft);
  color: var(--text-soft);
  border-radius: 12px;
  cursor: pointer;
  transition: all .15s;
}
.icon-btn:hover { color: var(--brand); border-color: var(--brand); }
.menu-btn { display: none; }

.ic-moon { display: none; }
[data-theme="dark"] .ic-sun { display: none; }
[data-theme="dark"] .ic-moon { display: block; }

/* ===== Content ===== */
.content { padding: 30px 34px 60px; max-width: 1400px; margin: 0 auto; }

.hero {
  padding: 28px 32px;
  border-radius: 20px;
  background:
    radial-gradient(1200px 200px at 0% 0%, rgba(108,92,231,.16), transparent 60%),
    radial-gradient(900px 220px at 100% 100%, rgba(0,184,212,.14), transparent 55%),
    var(--bg-elev);
  border: 1px solid var(--border);
  margin-bottom: 28px;
  box-shadow: var(--shadow-sm);
}
.hero-title { font-size: 30px; font-weight: 800; letter-spacing: .5px; }
.grad {
  background: var(--brand-grad);
  -webkit-background-clip: text; background-clip: text;
  -webkit-text-fill-color: transparent;
}
.hero-sub { margin-top: 8px; color: var(--text-soft); font-size: 15px; max-width: 680px; }
.hero-sub b { color: var(--brand); font-size: 17px; }
.hero-tags { margin-top: 16px; display: flex; flex-wrap: wrap; gap: 8px; }
.hero-tag {
  font-size: 13px; padding: 5px 13px;
  border-radius: 20px;
  background: var(--bg-soft);
  color: var(--text-soft);
  border: 1px solid var(--border);
  cursor: pointer;
  transition: all .15s;
}
.hero-tag:hover { color: #fff; background: var(--brand); border-color: var(--brand); }

.search-result-bar {
  display: flex; align-items: center; justify-content: space-between;
  padding: 12px 18px; margin-bottom: 20px;
  background: var(--bg-elev); border: 1px solid var(--border);
  border-radius: 12px; font-size: 14px; color: var(--text-soft);
}
.clear-btn {
  border: none; background: var(--bg-soft); color: var(--text-soft);
  padding: 5px 12px; border-radius: 8px; cursor: pointer; font-size: 13px;
}
.clear-btn:hover { color: var(--brand); }

/* ===== Sections ===== */
.cat-section { margin-bottom: 38px; scroll-margin-top: 80px; }
.cat-head {
  display: flex; align-items: center; gap: 10px;
  margin-bottom: 16px;
}
.cat-head .bar { width: 4px; height: 20px; border-radius: 4px; background: var(--brand-grad); }
.cat-head h2 { font-size: 19px; font-weight: 700; }
.cat-head .num { color: var(--text-mut); font-size: 13.5px; font-weight: 500; }

.tool-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(232px, 1fr));
  gap: 14px;
}

.tool-card {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 15px;
  background: var(--bg-elev);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  transition: transform .16s ease, box-shadow .16s ease, border-color .16s;
  position: relative;
  overflow: hidden;
}
.tool-card::before {
  content: "";
  position: absolute; inset: 0 auto 0 0;
  width: 3px; background: var(--brand-grad);
  transform: scaleY(0); transform-origin: bottom;
  transition: transform .18s ease;
}
.tool-card:hover {
  transform: translateY(-3px);
  box-shadow: var(--shadow-md);
  border-color: color-mix(in srgb, var(--brand) 40%, var(--border));
}
.tool-card:hover::before { transform: scaleY(1); }

.tool-ico {
  width: 42px; height: 42px;
  border-radius: 11px;
  flex-shrink: 0;
  object-fit: cover;
  background: var(--bg-soft);
  border: 1px solid var(--border);
}
.tool-ico-fallback {
  width: 42px; height: 42px;
  border-radius: 11px; flex-shrink: 0;
  display: grid; place-items: center;
  color: #fff; font-weight: 700; font-size: 17px;
  background: var(--brand-grad);
}
.tool-body { min-width: 0; flex: 1; }
.tool-name {
  font-size: 14.5px; font-weight: 600;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
  display: flex; align-items: center; gap: 6px;
}
.tool-name .src-dot {
  width: 6px; height: 6px; border-radius: 50%; flex-shrink: 0;
  background: var(--brand-2);
}
.tool-desc {
  font-size: 12.5px; color: var(--text-soft);
  margin-top: 4px;
  display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical;
  overflow: hidden;
  min-height: 34px;
}

.empty-state {
  text-align: center; padding: 80px 20px; color: var(--text-mut);
}
.empty-state .big { font-size: 48px; margin-bottom: 12px; }

.site-footer {
  margin-top: 50px; padding-top: 26px;
  border-top: 1px solid var(--border);
  text-align: center; color: var(--text-mut); font-size: 13px;
}
.footer-meta { margin-top: 6px; font-size: 12px; }

.to-top {
  position: fixed; right: 28px; bottom: 28px;
  width: 46px; height: 46px; border-radius: 50%;
  border: none; cursor: pointer;
  background: var(--brand); color: #fff;
  font-size: 20px;
  box-shadow: var(--shadow-md);
  z-index: 25;
  transition: transform .15s, opacity .2s;
}
.to-top:hover { transform: translateY(-3px); }

.overlay {
  display: none;
  position: fixed; inset: 0;
  background: rgba(0,0,0,.45);
  z-index: 38;
}

/* skeleton */
.skeleton { animation: pulse 1.4s ease-in-out infinite; background: var(--bg-soft); border-radius: 8px; }
@keyframes pulse { 0%,100%{opacity:1} 50%{opacity:.5} }

/* ===== Responsive ===== */
@media (max-width: 900px) {
  .sidebar { transform: translateX(-100%); transition: transform .25s ease; }
  .sidebar.open { transform: translateX(0); }
  .main { margin-left: 0; }
  .menu-btn { display: grid; }
  .overlay.show { display: block; }
  .search-kbd { display: none; }
  .content { padding: 22px 18px 50px; }
  .hero { padding: 22px; }
  .hero-title { font-size: 24px; }
}
@media (max-width: 520px) {
  .tool-grid { grid-template-columns: 1fr 1fr; gap: 10px; }
  .tool-desc { display: none; }
  .tool-card { flex-direction: column; gap: 8px; padding: 12px; }
}