/* ===== CSS 变量 ===== */
:root {
  --primary: #1a73e8;
  --primary-dark: #1558b0;
  --primary-light: #4a9ef8;
  --accent: #ff6b35;
  --bg: #f5f7fa;
  --bg-card: #ffffff;
  --text: #1a1a2e;
  --text-muted: #666;
  --text-light: #999;
  --border: #e8eaed;
  --shadow-sm: 0 2px 8px rgba(0,0,0,0.08);
  --shadow: 0 4px 20px rgba(0,0,0,0.1);
  --shadow-hover: 0 8px 30px rgba(0,0,0,0.15);
  --radius: 12px;
  --radius-sm: 8px;
  --navbar-h: 56px;
  --sidebar-w: 160px;
  --transition: 0.25s ease;
}

/* ===== Reset ===== */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
body { font-family: -apple-system, BlinkMacSystemFont, 'PingFang SC', 'Microsoft YaHei', sans-serif; background: var(--bg); color: var(--text); line-height: 1.6; }
a { text-decoration: none; color: inherit; }
img { max-width: 100%; height: auto; display: block; }

/* ===== Progress Bar ===== */
.progress-bar { position: fixed; top: 0; left: 0; height: 3px; width: 0; background: linear-gradient(90deg, var(--primary), var(--primary-light)); z-index: 9999; transition: width 0.1s; }

/* ===== Navbar ===== */
#navbar {
  position: fixed; top: 0; left: 0; right: 0; height: var(--navbar-h);
  background: rgba(255,255,255,0.98); backdrop-filter: blur(10px);
  border-bottom: 1px solid transparent;
  z-index: 1000; transition: all var(--transition);
}
#navbar.scrolled { border-bottom-color: var(--border); box-shadow: var(--shadow-sm); }
.nav-con { max-width: 100%; margin: 0 auto; padding: 0 16px; height: 100%; display: flex; align-items: center; gap: 12px; }
.nav-sidebar-toggle { display: none; background: none; border: none; font-size: 20px; cursor: pointer; padding: 4px 8px; color: var(--text); }
.nav-logo { display: flex; align-items: center; gap: 8px; font-weight: 700; font-size: 16px; color: var(--primary); }
.nav-logo-icon { width: 30px; height: 30px; background: var(--primary); border-radius: 6px; display: flex; align-items: center; justify-content: center; color: #fff; font-size: 14px; }
.nav-links { display: flex; align-items: center; gap: 4px; margin-left: auto; }
.nav-links a { padding: 6px 12px; border-radius: 6px; font-size: 13px; color: var(--text-muted); transition: all var(--transition); }
.nav-links a:hover, .nav-links a.active { background: #e8f0fe; color: var(--primary); }
.nav-hamburger { display: none; flex-direction: column; gap: 4px; cursor: pointer; padding: 4px; }
.nav-hamburger span { width: 20px; height: 2px; background: var(--text); border-radius: 2px; transition: all var(--transition); display: block; }

/* ===== Mobile Menu ===== */
.mobile-menu { display: none; position: fixed; top: 0; left: 0; right: 0; bottom: 0; background: #fff; z-index: 2000; padding: 20px; overflow-y: auto; }
.mobile-menu.open { display: block; }
.mobile-close { position: absolute; top: 16px; right: 16px; background: none; border: none; font-size: 22px; cursor: pointer; color: var(--text); }
.mobile-nav-links { margin-top: 50px; display: flex; flex-direction: column; gap: 4px; }
.mobile-nav-links a { display: block; padding: 12px 16px; font-size: 16px; border-radius: var(--radius-sm); color: var(--text); border-bottom: 1px solid var(--border); }
.mobile-nav-links a:hover { background: #e8f0fe; color: var(--primary); }

/* ===== Sidebar ===== */
.sidebar {
  position: fixed;
  top: var(--navbar-h);
  left: 0;
  width: var(--sidebar-w);
  height: calc(100vh - var(--navbar-h));
  background: var(--bg-card);
  border-right: 1px solid var(--border);
  overflow-y: auto;
  z-index: 900;
}
.sidebar-header {
  padding: 12px;
  border-bottom: 1px solid var(--border);
}
.sidebar-title {
  font-size: 11px;
  font-weight: 600;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}
.sidebar-list {
  padding: 6px 0;
}
.sidebar-item {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 10px 12px;
  cursor: pointer;
  transition: all var(--transition);
  border-left: 3px solid transparent;
}
.sidebar-item:hover {
  background: #f0f6ff;
}
.sidebar-item.active {
  background: #e8f0fe;
  border-left-color: var(--primary);
}
.sidebar-item-icon {
  font-size: 14px;
  width: 20px;
  text-align: center;
}
.sidebar-item-name {
  flex: 1;
  font-size: 13px;
  font-weight: 500;
  color: var(--text);
  white-space: normal;
  overflow: visible;
  text-overflow: unset;
}
.sidebar-item.active .sidebar-item-name {
  color: var(--primary);
  font-weight: 600;
}
.sidebar-item-count {
  display: none;
}

/* ===== Content Wrap ===== */
.content-wrap {
  margin-left: var(--sidebar-w);
  margin-top: var(--navbar-h);
  min-height: calc(100vh - var(--navbar-h));
}

/* ===== Search Bar ===== */
.search-wrap {
  background: var(--bg-card);
  padding: 16px 20px;
  border-bottom: 1px solid var(--border);
}
.search-inner {
  max-width: 600px;
  display: flex;
  gap: 8px;
}
.search-input {
  flex: 1;
  padding: 10px 16px;
  border: 1.5px solid var(--border);
  border-radius: 24px;
  font-size: 14px;
  outline: none;
  transition: border-color var(--transition);
}
.search-input:focus {
  border-color: var(--primary);
}
.search-btn {
  width: 42px;
  height: 42px;
  background: var(--primary);
  color: #fff;
  border: none;
  border-radius: 50%;
  font-size: 16px;
  cursor: pointer;
  transition: background var(--transition);
  display: flex;
  align-items: center;
  justify-content: center;
}
.search-btn:hover {
  background: var(--primary-dark);
}

/* ===== Course List ===== */
.main {
  padding: 20px;
}
.course-list-header {
  font-size: 13px;
  color: var(--text-muted);
  margin-bottom: 12px;
  padding-left: 4px;
}
.course-item-list {
  background: var(--bg-card);
  border-radius: var(--radius);
  border: 1px solid var(--border);
  overflow: hidden;
}
.course-item {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 14px 16px;
  border-bottom: 1px solid var(--border);
  transition: background var(--transition);
  cursor: pointer;
}
.course-item:last-child {
  border-bottom: none;
}
.course-item:hover {
  background: #f8fbff;
}
.course-item-icon {
  width: 36px;
  height: 36px;
  background: var(--primary);
  color: #fff;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  flex-shrink: 0;
}
.course-item:hover .course-item-icon {
  background: var(--accent);
}
.course-item-info {
  flex: 1;
  min-width: 0;
}
.course-item-title {
  font-size: 14px;
  font-weight: 500;
  color: var(--text);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.course-item-arrow {
  color: var(--text-light);
  font-size: 18px;
  flex-shrink: 0;
}

/* ===== Course Grid ===== */
.course-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(280px, 1fr)); gap: 24px; }
.course-card { background: var(--bg-card); border-radius: var(--radius); overflow: hidden; box-shadow: var(--shadow-sm); transition: all var(--transition); display: block; border: 1px solid var(--border); }
.course-card:hover { transform: translateY(-4px); box-shadow: var(--shadow-hover); border-color: var(--primary); }
.course-card-thumb { position: relative; aspect-ratio: 16/9; background: linear-gradient(135deg, #e8f0fe, #c2d4f8); overflow: hidden; }
.course-card-thumb img { width: 100%; height: 100%; object-fit: cover; }
.course-thumb-icon { width: 100%; height: 100%; display: flex; align-items: center; justify-content: center; font-size: 40px; }
.course-duration { position: absolute; bottom: 8px; right: 8px; background: rgba(0,0,0,0.75); color: #fff; font-size: 11px; padding: 2px 8px; border-radius: 4px; }
.play-overlay { position: absolute; inset: 0; display: flex; align-items: center; justify-content: center; background: rgba(0,0,0,0.2); opacity: 0; transition: opacity var(--transition); }
.course-card:hover .play-overlay { opacity: 1; }
.play-btn-circle { width: 48px; height: 48px; background: rgba(255,255,255,0.9); border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 20px; }
.course-card-body { padding: 16px; }
.course-card-cat { display: inline-block; background: #e8f0fe; color: var(--primary); font-size: 11px; padding: 2px 10px; border-radius: 20px; margin-bottom: 8px; }
.course-card-title { font-size: 15px; font-weight: 600; line-height: 1.5; margin-bottom: 6px; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.course-card-desc { font-size: 12px; color: var(--text-muted); display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; margin-bottom: 10px; }
.course-card-meta { display: flex; align-items: center; gap: 12px; font-size: 12px; color: var(--text-light); }

/* ===== Course Card (Text-only list style) ===== */
.course-grid:has(.course-card-text) { display: flex; flex-direction: column; gap: 0; }
.course-card-text { display: flex; align-items: center; gap: 14px; padding: 14px 18px; border-radius: 0; border: none; border-bottom: 1px solid var(--border); box-shadow: none; background: var(--bg-card); }
.course-card-text:first-child { border-top-left-radius: var(--radius); border-top-right-radius: var(--radius); }
.course-card-text:last-child { border-bottom-left-radius: var(--radius); border-bottom-right-radius: var(--radius); border-bottom: none; }
.course-card-text:hover { transform: none; box-shadow: none; background: #f0f6ff; border-color: var(--border); }
.course-card-text .course-card-play { flex-shrink: 0; width: 32px; height: 32px; background: var(--primary); color: #fff; border-radius: 50%; display: flex; align-items: center; justify-content: center; font-size: 12px; transition: background var(--transition); }
.course-card-text:hover .course-card-play { background: var(--accent); }
.course-card-text .course-card-body { flex: 1; min-width: 0; padding: 0; }
.course-card-text .course-card-title { font-size: 15px; font-weight: 600; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; margin-bottom: 3px; display: block; -webkit-line-clamp: unset; -webkit-box-orient: unset; }
.course-card-text .course-card-meta { display: flex; flex-wrap: wrap; gap: 10px; font-size: 12px; color: var(--text-light); }
/* 把整个 grid 外层包一个白底圆角容器 */
.panel.active > .course-grid { background: var(--bg-card); border-radius: var(--radius); border: 1px solid var(--border); overflow: hidden; box-shadow: var(--shadow-sm); }

/* ===== Empty State ===== */
.empty-state { text-align: center; padding: 80px 20px; }
.empty-icon { font-size: 60px; margin-bottom: 16px; }
.empty-state p { color: var(--text-muted); font-size: 15px; }

/* ===== Course Detail Page ===== */
.course-page { max-width: 960px; margin: 0 auto; padding: calc(var(--navbar-h) + 24px) 20px 60px; }
.course-breadcrumb { font-size: 13px; color: var(--text-muted); margin-bottom: 16px; }
.course-breadcrumb a { color: var(--primary); }
.course-breadcrumb a:hover { text-decoration: underline; }
.course-title { font-size: clamp(20px, 4vw, 30px); font-weight: 700; margin-bottom: 14px; line-height: 1.4; }
.course-meta { display: flex; flex-wrap: wrap; gap: 12px; margin-bottom: 20px; align-items: center; }
.course-tag { background: var(--primary); color: #fff; padding: 4px 14px; border-radius: 20px; font-size: 12px; }
.course-meta-item { font-size: 13px; color: var(--text-muted); }
.course-video-wrap { margin-bottom: 24px; }
.video-player { width: 100%; max-height: 540px; border-radius: var(--radius); background: #000; display: block; }
.video-embed-wrap { position: relative; padding-bottom: 56.25%; border-radius: var(--radius); overflow: hidden; background: #000; }
.video-embed-wrap iframe { position: absolute; inset: 0; width: 100%; height: 100%; }
.video-placeholder { aspect-ratio: 16/9; background: linear-gradient(135deg, #e8f0fe, #c2d4f8); border-radius: var(--radius); display: flex; flex-direction: column; align-items: center; justify-content: center; gap: 12px; color: var(--text-muted); }
.video-placeholder-icon { font-size: 60px; }
.course-desc { background: var(--bg-card); border-radius: var(--radius); padding: 24px; border: 1px solid var(--border); font-size: 15px; line-height: 1.8; color: var(--text); margin-bottom: 32px; }
.course-desc p { margin-bottom: 12px; }

/* ===== Category Page ===== */
.cat-page { max-width: 1200px; margin: 0 auto; padding: calc(var(--navbar-h) + 20px) 20px 60px; }
.cat-back { margin-bottom: 16px; }
.cat-back a { color: var(--primary); font-size: 13px; }
.cat-list-header { display: flex; align-items: center; justify-content: space-between; padding: 12px 16px; background: var(--bg-card); border: 1px solid var(--border); border-radius: var(--radius-sm); margin-bottom: 12px; }
.cat-list-name { font-size: 15px; font-weight: 600; color: var(--text); }
.cat-list-count { font-size: 13px; color: var(--text-muted); }

/* ===== Related Section ===== */
.related-section { margin-top: 40px; }
.related-title { font-size: 18px; font-weight: 700; margin-bottom: 16px; padding-bottom: 12px; border-bottom: 2px solid var(--border); }
.related-grid { display: flex; flex-direction: column; gap: 12px; }
.related-card { display: flex; gap: 12px; background: var(--bg-card); border-radius: var(--radius-sm); overflow: hidden; border: 1px solid var(--border); transition: all var(--transition); }
.related-card:hover { border-color: var(--primary); box-shadow: var(--shadow-sm); }
.related-card-thumb { width: 120px; min-width: 120px; aspect-ratio: 16/9; background: linear-gradient(135deg, #e8f0fe, #c2d4f8); overflow: hidden; display: flex; align-items: center; justify-content: center; }
.related-card-thumb img { width: 100%; height: 100%; object-fit: cover; }
.related-card-body { padding: 10px 12px; flex: 1; display: flex; flex-direction: column; justify-content: center; }
.related-card-title { font-size: 14px; font-weight: 600; display: -webkit-box; -webkit-line-clamp: 2; -webkit-box-orient: vertical; overflow: hidden; }
.related-card-meta { font-size: 12px; color: var(--text-muted); margin-top: 4px; }

/* ===== Footer ===== */
footer { background: #1a1a2e; color: rgba(255,255,255,0.6); text-align: center; padding: 32px 20px; font-size: 13px; }
footer .footer-logo { color: var(--primary-light); font-size: 18px; font-weight: 700; margin-bottom: 6px; }
footer p { margin-top: 4px; }

/* ===== Back to Top ===== */
.back-top { position: fixed; bottom: 32px; right: 24px; width: 42px; height: 42px; background: var(--primary); color: #fff; border: none; border-radius: 50%; cursor: pointer; font-size: 18px; box-shadow: 0 4px 14px rgba(26,115,232,0.4); opacity: 0; transform: translateY(20px); transition: all var(--transition); z-index: 500; }
.back-top.show { opacity: 1; transform: translateY(0); }
.back-top:hover { background: var(--primary-dark); transform: translateY(-3px); }

/* ===== Admin ===== */
.admin-wrap { max-width: 1100px; margin: 0 auto; padding: calc(var(--navbar-h) + 24px) 20px 60px; }
.admin-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 24px; flex-wrap: wrap; gap: 12px; }
.admin-title { font-size: 22px; font-weight: 700; }
.admin-tabs { display: flex; gap: 8px; margin-bottom: 24px; border-bottom: 2px solid var(--border); }
.admin-tab { padding: 10px 20px; font-size: 14px; cursor: pointer; color: var(--text-muted); border-bottom: 3px solid transparent; margin-bottom: -2px; font-weight: 500; transition: all var(--transition); }
.admin-tab.active { color: var(--primary); border-bottom-color: var(--primary); }
.admin-panel { display: none; }
.admin-panel.active { display: block; }
.admin-table-wrap { background: var(--bg-card); border-radius: var(--radius); overflow: hidden; border: 1px solid var(--border); overflow-x: auto; }
table { width: 100%; border-collapse: collapse; }
th { background: #f8f9fa; padding: 12px 16px; text-align: left; font-size: 13px; color: var(--text-muted); font-weight: 600; white-space: nowrap; }
td { padding: 14px 16px; border-top: 1px solid var(--border); font-size: 14px; vertical-align: middle; }
tr:hover td { background: #fafbff; }
.td-thumb { width: 80px; height: 45px; border-radius: 4px; object-fit: cover; background: linear-gradient(135deg, #e8f0fe, #c2d4f8); display: flex; align-items: center; justify-content: center; font-size: 20px; }
.badge { display: inline-block; padding: 2px 10px; border-radius: 20px; font-size: 11px; font-weight: 600; }
.badge-green { background: #e6f4ea; color: #1e8e3e; }
.badge-gray { background: #f1f3f4; color: #888; }

/* ===== Buttons ===== */
.btn { display: inline-flex; align-items: center; gap: 6px; padding: 8px 18px; border-radius: var(--radius-sm); font-size: 14px; cursor: pointer; border: none; transition: all var(--transition); font-weight: 500; }
.btn-primary { background: var(--primary); color: #fff; }
.btn-primary:hover { background: var(--primary-dark); }
.btn-danger { background: #fce8e6; color: #c62828; }
.btn-danger:hover { background: #c62828; color: #fff; }
.btn-text { background: none; color: var(--primary); padding: 4px 8px; }
.btn-text:hover { background: #e8f0fe; }
.btn-sm { padding: 5px 12px; font-size: 12px; }
.btn-block { width: 100%; justify-content: center; padding: 12px; }

/* ===== Form ===== */
.modal-mask { display: none; position: fixed; inset: 0; background: rgba(0,0,0,0.5); z-index: 3000; align-items: center; justify-content: center; padding: 20px; }
.modal-mask.open { display: flex; }
.modal { background: #fff; border-radius: var(--radius); padding: 28px; width: 100%; max-width: 560px; max-height: 90vh; overflow-y: auto; }
.modal-header { display: flex; align-items: center; justify-content: space-between; margin-bottom: 20px; }
.modal-title { font-size: 18px; font-weight: 700; }
.modal-close { background: none; border: none; font-size: 20px; cursor: pointer; color: var(--text-muted); padding: 4px; }
.form-group { margin-bottom: 16px; }
.form-label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 6px; color: var(--text); }
.form-label span { color: #c62828; }
.form-control { width: 100%; padding: 10px 14px; border: 1.5px solid var(--border); border-radius: var(--radius-sm); font-size: 14px; outline: none; transition: border-color var(--transition); }
.form-control:focus { border-color: var(--primary); }
textarea.form-control { resize: vertical; min-height: 100px; }
.form-row { display: grid; grid-template-columns: 1fr 1fr; gap: 12px; }
.form-hint { font-size: 11px; color: var(--text-muted); margin-top: 4px; }
.radio-group { display: flex; gap: 16px; }
.radio-group label { display: flex; align-items: center; gap: 6px; font-size: 14px; cursor: pointer; }

/* ===== Upload Area ===== */
.upload-area { border: 2px dashed var(--border); border-radius: var(--radius-sm); padding: 24px; text-align: center; cursor: pointer; transition: all var(--transition); }
.upload-area:hover, .upload-area.drag { border-color: var(--primary); background: #f0f6ff; }
.upload-area-icon { font-size: 32px; margin-bottom: 8px; }
.upload-area-text { font-size: 14px; color: var(--text-muted); }
.upload-progress { margin-top: 10px; }
.upload-progress-bar { height: 6px; background: #e8f0fe; border-radius: 3px; overflow: hidden; }
.upload-progress-fill { height: 100%; background: var(--primary); transition: width 0.2s; border-radius: 3px; }
.upload-progress-text { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.preview-thumb { width: 120px; height: 68px; object-fit: cover; border-radius: 6px; margin-top: 8px; }
.preview-video-name { font-size: 12px; color: var(--primary); margin-top: 6px; background: #e8f0fe; padding: 4px 10px; border-radius: 4px; display: inline-block; }

/* ===== Build Panel ===== */
.build-card { background: var(--bg-card); border-radius: var(--radius); padding: 28px; border: 1px solid var(--border); }
.build-stats { display: grid; grid-template-columns: repeat(auto-fill, minmax(140px, 1fr)); gap: 16px; margin: 20px 0; }
.build-stat { background: #f8f9fa; border-radius: var(--radius-sm); padding: 16px; text-align: center; }
.build-stat-num { font-size: 26px; font-weight: 700; color: var(--primary); }
.build-stat-label { font-size: 12px; color: var(--text-muted); margin-top: 4px; }
.build-log { background: #1a1a2e; color: #aef; border-radius: var(--radius-sm); padding: 16px; font-family: monospace; font-size: 13px; max-height: 200px; overflow-y: auto; margin-top: 16px; display: none; }
.build-log.show { display: block; }

/* ===== Toast ===== */
.toast { position: fixed; bottom: 80px; left: 50%; transform: translateX(-50%) translateY(20px); background: #1a1a2e; color: #fff; padding: 10px 24px; border-radius: 30px; font-size: 14px; z-index: 9999; opacity: 0; transition: all 0.3s; pointer-events: none; white-space: nowrap; }
.toast.show { opacity: 1; transform: translateX(-50%) translateY(0); }
.toast-msg { position: fixed; bottom: 80px; left: 50%; transform: translateX(-50%) translateY(20px); background: #1a1a2e; color: #fff; padding: 10px 24px; border-radius: 30px; font-size: 14px; z-index: 9999; opacity: 0; transition: all 0.3s; pointer-events: none; white-space: nowrap; }
.toast-msg.fade { opacity: 0; transform: translateX(-50%) translateY(-10px); }
.toast-msg { animation: toastIn 0.3s ease forwards; }
@keyframes toastIn { from { opacity: 0; transform: translateX(-50%) translateY(20px); } to { opacity: 1; transform: translateX(-50%) translateY(0); } }

/* ===== Share Bar ===== */
.share-bar { display: flex; align-items: center; gap: 10px; margin-bottom: 20px; flex-wrap: wrap; }
.share-label { font-size: 13px; color: var(--text-muted); font-weight: 500; }
.share-btn { display: inline-flex; align-items: center; gap: 6px; padding: 7px 16px; border-radius: 20px; font-size: 13px; cursor: pointer; border: 1.5px solid var(--border); background: #fff; color: var(--text); transition: all var(--transition); font-weight: 500; }
.share-btn:hover { border-color: var(--primary); color: var(--primary); background: #f0f6ff; }
.share-wechat { border-color: #07c160; color: #07c160; }
.share-wechat:hover { background: #07c160; color: #fff; }
.share-wechat svg { width: 18px; height: 18px; }
.share-copy svg { width: 16px; height: 16px; }

/* ===== Responsive ===== */
@media (max-width: 768px) {
  /* Navbar - 简约 */
  .nav-links { display: none; }
  .nav-hamburger { display: flex; }
  .nav-logo span { display: none; }

  /* Sidebar - 固定宽度不缩小 */
  .sidebar { width: 90px; }
  .sidebar-item-name { font-size: 12px; white-space: normal; overflow: visible; text-overflow: unset; max-width: none; }
  .sidebar-item-icon { display: none; }
  .sidebar-item-count { display: none; }
  .sidebar-header { padding: 10px 8px; }
  .sidebar-item { padding: 10px 8px; text-align: center; }

  /* Content - 课程列表贴着边栏 */
  .content-wrap { margin-left: 90px; }
  .main { padding: 12px 10px; }
  .course-item { padding: 12px 10px; }
  .course-item-title { font-size: 14px; white-space: nowrap; overflow: hidden; text-overflow: ellipsis; }
  .course-item-arrow { font-size: 16px; }
  .course-list-header { font-size: 12px; padding: 8px 10px; }

  /* Search */
  .search-wrap { padding: 10px 10px; }
  .search-inner { max-width: 100%; }
  .search-input { padding: 8px 12px; font-size: 13px; }

  /* Category page - 简约 */
  .cat-page { padding: calc(var(--navbar-h) + 12px) 10px 40px; }
  .cat-list-header { padding: 10px 12px; }
  .cat-list-name { font-size: 14px; }

  /* Others */
  .admin-wrap { padding: calc(var(--navbar-h) + 12px) 10px 40px; }
  .course-page { padding: calc(var(--navbar-h) + 12px) 10px 40px; }
  .course-title { font-size: 18px; }
  .course-breadcrumb { font-size: 12px; }
  .share-bar { margin-bottom: 16px; }
}
@media (max-width: 480px) {
  .sidebar { width: 60px; }
  .sidebar-item-name { font-size: 11px; }
  .sidebar-item-count { display: none; }
  .sidebar-header { display: none; }
  .content-wrap { margin-left: 60px; }
}