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

:root {
  --accent:       #4f6ef7;
  --accent-light: rgba(79, 110, 247, 0.12);
  --bg:           #f5f6fa;
  --sidebar-bg:   #1e1e2e;
  --sidebar-text: #a6adc8;
  --card-bg:      #ffffff;
  --text:         #2d3748;
  --text-muted:   #718096;
  --border:       #e2e8f0;
  --radius:       12px;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC',
               'Microsoft YaHei', sans-serif;
  background: var(--bg);
  color: var(--text);
  display: flex;
  height: 100vh;
  overflow: hidden;
}

/* Sidebar */
.sidebar {
  width: 220px;
  background: var(--sidebar-bg);
  color: var(--sidebar-text);
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
  overflow-y: auto;
}

.sidebar-logo {
  padding: 22px 20px 18px;
  font-size: 1.15rem;
  font-weight: 700;
  color: #fff;
  border-bottom: 1px solid rgba(255,255,255,0.07);
  letter-spacing: .5px;
  user-select: none;
}

.sidebar-logo span { color: var(--accent); }

.sidebar-nav { padding: 10px 0; flex: 1; }

.nav-item {
  display: flex;
  align-items: center;
  gap: 9px;
  padding: 10px 20px;
  cursor: pointer;
  font-size: .88rem;
  transition: background .15s, color .15s;
  color: var(--sidebar-text);
  user-select: none;
  border-left: 3px solid transparent;
}

.nav-item:hover { background: rgba(255,255,255,0.06); color: #fff; }

.nav-item.active {
  background: rgba(79,110,247,0.16);
  color: #fff;
  border-left-color: var(--accent);
}

.nav-count {
  margin-left: auto;
  background: rgba(255,255,255,0.1);
  color: var(--sidebar-text);
  font-size: .72rem;
  padding: 1px 7px;
  border-radius: 10px;
}

/* Main */
.main {
  flex: 1;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.header {
  background: #fff;
  border-bottom: 1px solid var(--border);
  padding: 14px 28px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-shrink: 0;
}

.header-title {
  font-size: 1rem;
  font-weight: 600;
  white-space: nowrap;
}

.search-wrap {
  flex: 1;
  max-width: 380px;
  position: relative;
}

.search-wrap input {
  width: 100%;
  padding: 8px 14px 8px 36px;
  border: 1px solid var(--border);
  border-radius: 8px;
  font-size: .88rem;
  outline: none;
  background: var(--bg);
  color: var(--text);
  transition: border-color .2s, box-shadow .2s;
}

.search-wrap input:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 3px var(--accent-light);
}

.search-icon {
  position: absolute;
  left: 11px;
  top: 50%;
  transform: translateY(-50%);
  font-size: .88rem;
  pointer-events: none;
}

.tools-count {
  margin-left: auto;
  font-size: .82rem;
  color: var(--text-muted);
  white-space: nowrap;
}

.content {
  flex: 1;
  overflow-y: auto;
  padding: 28px;
}

.section { margin-bottom: 36px; }

.section-title {
  font-size: .95rem;
  font-weight: 600;
  margin-bottom: 14px;
  display: flex;
  align-items: center;
  gap: 6px;
}

.section-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--border);
  margin-left: 8px;
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(210px, 1fr));
  gap: 14px;
}

.card {
  background: var(--card-bg);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 18px;
  display: flex;
  flex-direction: column;
  gap: 7px;
  text-decoration: none;
  color: inherit;
  transition: transform .15s, box-shadow .15s, border-color .15s;
}

.card:hover {
  transform: translateY(-3px);
  box-shadow: 0 8px 24px rgba(79,110,247,0.13);
  border-color: var(--accent);
}

.card-icon { font-size: 2rem; line-height: 1; }

.card-name { font-size: .92rem; font-weight: 600; margin-top: 2px; }

.card-desc { font-size: .8rem; color: var(--text-muted); line-height: 1.55; flex: 1; }

.card-open {
  margin-top: 6px;
  font-size: .78rem;
  color: var(--accent);
  font-weight: 500;
}

.state-msg {
  text-align: center;
  padding: 80px 20px;
  color: var(--text-muted);
}

.state-icon { font-size: 2.8rem; margin-bottom: 14px; }

.state-msg p { font-size: .88rem; line-height: 1.8; }

.state-msg code {
  background: var(--border);
  padding: 1px 6px;
  border-radius: 4px;
  font-size: .84rem;
}

mark {
  background: rgba(79,110,247,0.15);
  color: var(--accent);
  border-radius: 2px;
}

::-webkit-scrollbar { width: 5px; }

::-webkit-scrollbar-track { background: transparent; }

::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

@media (max-width: 600px) {
  .sidebar { width: 64px; }
  .sidebar-logo, .nav-item span:not(.nav-count), .nav-count { display: none; }
  .nav-item { justify-content: center; padding: 12px; }
  .content { padding: 16px; }
  .header { padding: 12px 16px; }
}