/* ===== CSS Variables / Theme ===== */
:root {
  --clr-primary: #1a56db;
  --clr-primary-dark: #1040b0;
  --clr-primary-light: #e8f0fe;
  --clr-accent: #f59e0b;
  --clr-bg: #f4f6fb;
  --clr-surface: #ffffff;
  --clr-surface-2: #f0f4ff;
  --clr-border: #e2e8f0;
  --clr-text: #1a202c;
  --clr-text-sub: #64748b;
  --clr-text-muted: #94a3b8;
  --clr-hero-from: #0f2d6e;
  --clr-hero-to: #1a56db;
  --clr-sidebar-bg: #ffffff;
  --clr-sidebar-hover: #f0f4ff;
  --clr-sidebar-active-bg: #e8f0fe;
  --clr-sidebar-active-text: #1a56db;
  --clr-tag-featured: #1a56db;
  --clr-tag-popular: #059669;
  --clr-tag-hot: #dc2626;
  --clr-tag-new: #7c3aed;
  --clr-tag-enterprise: #b45309;
  --clr-tag-free: #0891b2;
  --radius-card: 12px;
  --radius-btn: 8px;
  --shadow-card: 0 1px 4px rgba(0,0,0,0.07), 0 4px 16px rgba(26,86,219,0.06);
  --shadow-card-hover: 0 8px 32px rgba(26,86,219,0.13);
  --sidebar-width: 220px;
  --header-height: 60px;
  --transition: 0.18s ease;
  --font-sans: 'Noto Sans SC', 'PingFang SC', 'Microsoft YaHei', sans-serif;
  --font-display: 'Outfit', 'Noto Sans SC', sans-serif;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  background: var(--clr-bg);
  color: var(--clr-text);
  display: flex;
  flex-direction: column;
  min-height: 100vh;
  font-size: 15px;
}
a { text-decoration: none; color: inherit; }
img { display: block; max-width: 100%; }
ul { list-style: none; }
button { cursor: pointer; font-family: inherit; }

/* ===== Layout ===== */
.layout {
  display: flex;
  flex: 1;
  min-height: calc(100vh - var(--header-height));
}

/* ===== Header ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  height: var(--header-height);
  background: var(--clr-surface);
  border-bottom: 1px solid var(--clr-border);
  display: flex;
  align-items: center;
  padding: 0 20px;
  gap: 16px;
  box-shadow: 0 1px 8px rgba(0,0,0,0.06);
}
.logo-area {
  display: flex;
  align-items: center;
  gap: 10px;
  flex-shrink: 0;
  width: var(--sidebar-width);
}
.logo-icon {
  width: 36px;
  height: 36px;
  background: linear-gradient(135deg, var(--clr-primary), #4f8ef7);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: #fff;
  font-size: 18px;
}
.logo-text {
  font-family: var(--font-display);
  font-size: 13.5px;
  font-weight: 700;
  color: var(--clr-text);
  line-height: 1.3;
}
.logo-text span { color: var(--clr-primary); }

.search-wrap {
  flex: 1;
  max-width: 520px;
  position: relative;
}
.search-wrap svg {
  position: absolute;
  left: 13px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--clr-text-muted);
  pointer-events: none;
}
#search-input {
  width: 100%;
  height: 40px;
  border: 1.5px solid var(--clr-border);
  border-radius: 20px;
  padding: 0 16px 0 40px;
  font-size: 14px;
  background: var(--clr-bg);
  color: var(--clr-text);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition);
}
#search-input:focus {
  border-color: var(--clr-primary);
  box-shadow: 0 0 0 3px rgba(26,86,219,0.12);
  background: #fff;
}
#search-input::placeholder { color: var(--clr-text-muted); }

.header-actions {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 10px;
}

.btn-mobile-menu {
  display: none;
  width: 36px;
  height: 36px;
  background: var(--clr-bg);
  border: 1px solid var(--clr-border);
  border-radius: 8px;
  align-items: center;
  justify-content: center;
  color: var(--clr-text);
}

/* ===== Sidebar ===== */
.sidebar {
  width: var(--sidebar-width);
  background: var(--clr-sidebar-bg);
  border-right: 1px solid var(--clr-border);
  flex-shrink: 0;
  padding: 16px 0;
  position: sticky;
  top: var(--header-height);
  height: calc(100vh - var(--header-height));
  overflow-y: auto;
}
.sidebar-nav { display: flex; flex-direction: column; gap: 2px; padding: 0 10px; }
.nav-item {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 10px 12px;
  border-radius: 8px;
  font-size: 14px;
  font-weight: 500;
  color: var(--clr-text-sub);
  cursor: pointer;
  transition: background var(--transition), color var(--transition);
  border: none;
  background: transparent;
  width: 100%;
  text-align: left;
}
.nav-item:hover { background: var(--clr-sidebar-hover); color: var(--clr-text); }
.nav-item.active {
  background: var(--clr-sidebar-active-bg);
  color: var(--clr-sidebar-active-text);
  font-weight: 700;
}
.nav-item .nav-icon { font-size: 16px; width: 20px; text-align: center; }
.sidebar-divider { height: 1px; background: var(--clr-border); margin: 10px 12px; }

/* ===== Main Content ===== */
.main-content {
  flex: 1;
  min-width: 0;
  padding: 0 0 40px;
}

/* ===== Hero Banner ===== */
.hero {
  background: linear-gradient(135deg, var(--clr-hero-from) 0%, var(--clr-hero-to) 60%, #3b82f6 100%);
  padding: 52px 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
}
.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.04'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}
.hero-content { position: relative; z-index: 1; }
.hero h1 {
  font-family: var(--font-display);
  font-size: clamp(24px, 4vw, 38px);
  font-weight: 800;
  color: #fff;
  letter-spacing: -0.5px;
  margin-bottom: 14px;
}
.hero p {
  font-size: 15px;
  color: rgba(255,255,255,0.82);
  max-width: 540px;
  margin: 0 auto;
  line-height: 1.7;
}

/* ===== Sort Bar ===== */
.sort-bar {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  gap: 8px;
  padding: 16px 32px;
  border-bottom: 1px solid var(--clr-border);
  background: var(--clr-surface);
}
.sort-bar label { font-size: 13px; color: var(--clr-text-sub); }
#sort-select {
  border: 1px solid var(--clr-border);
  border-radius: 6px;
  padding: 5px 10px;
  font-size: 13px;
  background: var(--clr-bg);
  color: var(--clr-text);
  outline: none;
  cursor: pointer;
}
.result-count {
  font-size: 13px;
  color: var(--clr-text-muted);
  margin-right: auto;
}

/* ===== Sections ===== */
.section { padding: 28px 32px; }
.section-title {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  color: var(--clr-text);
  margin-bottom: 18px;
  display: flex;
  align-items: center;
  gap: 8px;
}
.section-title::after {
  content: '';
  flex: 1;
  height: 1px;
  background: var(--clr-border);
}

/* ===== Cards Grid ===== */
.cards-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
}

/* ===== Card ===== */
.card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-card);
  padding: 18px 16px 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
  transition: box-shadow var(--transition), transform var(--transition), border-color var(--transition);
  cursor: pointer;
  position: relative;
  overflow: hidden;
}
.card:hover {
  box-shadow: var(--shadow-card-hover);
  transform: translateY(-3px);
  border-color: rgba(26,86,219,0.2);
}
.card-header {
  display: flex;
  align-items: flex-start;
  gap: 10px;
}
.card-logo {
  width: 44px;
  height: 44px;
  border: 1px solid var(--clr-border);
  border-radius: 10px;
  padding: 6px;
  object-fit: contain;
  flex-shrink: 0;
  background: #fff;
}
.card-logo-fallback {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  background: var(--clr-primary-light);
  flex-shrink: 0;
  font-weight: 700;
  color: var(--clr-primary);
}
.card-name {
  font-size: 14px;
  font-weight: 700;
  color: var(--clr-text);
  line-height: 1.4;
  flex: 1;
  margin-top: 2px;
}
.card-desc {
  font-size: 13px;
  color: var(--clr-text-sub);
  line-height: 1.6;
  flex: 1;
}
.card-footer {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-top: auto;
}
.card-tag {
  display: inline-block;
  padding: 2px 8px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.3px;
  color: #fff;
}
.tag-featured { background: var(--clr-tag-featured); }
.tag-popular  { background: var(--clr-tag-popular); }
.tag-hot      { background: var(--clr-tag-hot); }
.tag-new      { background: var(--clr-tag-new); }
.tag-enterprise { background: var(--clr-tag-enterprise); }
.tag-free     { background: var(--clr-tag-free); }

.card-views {
  font-size: 12px;
  color: var(--clr-text-muted);
  display: flex;
  align-items: center;
  gap: 4px;
}
.card-views svg { width: 13px; height: 13px; }

.card-link-btn {
  display: block;
  width: 100%;
  margin-top: 8px;
  height: 32px;
  border: 1.5px solid var(--clr-primary);
  color: var(--clr-primary);
  background: transparent;
  border-radius: 6px;
  font-size: 13px;
  font-weight: 600;
  transition: background var(--transition), color var(--transition);
  text-align: center;
  line-height: 29px;
}
.card-link-btn:hover {
  background: var(--clr-primary);
  color: #fff;
}

/* ===== Empty State ===== */
.empty-state {
  grid-column: 1 / -1;
  text-align: center;
  padding: 60px 20px;
  color: var(--clr-text-muted);
}
.empty-state .empty-icon { font-size: 48px; margin-bottom: 12px; }
.empty-state p { font-size: 15px; }

/* ===== Skeleton Loader ===== */
.skeleton {
  background: linear-gradient(90deg, var(--clr-border) 25%, #e8ecf4 50%, var(--clr-border) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.4s infinite;
  border-radius: 8px;
}
@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}
.skeleton-card {
  background: var(--clr-surface);
  border: 1px solid var(--clr-border);
  border-radius: var(--radius-card);
  padding: 18px 16px;
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.sk-logo { width: 44px; height: 44px; border-radius: 10px; }
.sk-title { height: 14px; width: 70%; }
.sk-desc { height: 12px; width: 100%; }
.sk-desc2 { height: 12px; width: 80%; }
.sk-btn { height: 32px; width: 100%; border-radius: 6px; }

/* ===== Footer ===== */
.site-footer {
  background: var(--clr-surface);
  border-top: 1px solid var(--clr-border);
  padding: 24px 32px;
  text-align: center;
  color: var(--clr-text-muted);
  font-size: 13px;
  line-height: 2;
}
.footer-icp { margin-top: 4px; font-size: 12px; }
.footer-icp a { color: var(--clr-text-muted); }
.footer-icp a:hover { color: var(--clr-primary); }

/* ===== Mobile Overlay ===== */
.sidebar-overlay {
  display: none;
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.4);
  z-index: 200;
}
.sidebar-overlay.active { display: block; }

/* ===== Responsive ===== */
@media (max-width: 1100px) {
  .cards-grid { grid-template-columns: repeat(3, 1fr); }
}
@media (max-width: 900px) {
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
  .hero { padding: 36px 24px; }
  .section { padding: 22px 20px; }
  .sort-bar { padding: 12px 20px; }
}
@media (max-width: 768px) {
  :root { --sidebar-width: 240px; }
  .sidebar {
    position: fixed;
    top: var(--header-height);
    left: 0;
    height: calc(100vh - var(--header-height));
    z-index: 201;
    transform: translateX(-100%);
    transition: transform 0.26s ease;
  }
  .sidebar.open { transform: translateX(0); }
  .main-content { width: 100%; }
  .logo-area { width: auto; }
  .btn-mobile-menu { display: flex; }
  .cards-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 480px) {
  .hero { padding: 28px 16px; }
  .section { padding: 18px 16px; }
  .sort-bar { padding: 10px 16px; }
  .cards-grid { grid-template-columns: 1fr; }
}