:root {
  --cream: #fdf8e7;
  --yellow: #f5d060;
  --yellow-dark: #d9a900;
  --ink: #2d2d2d;
  --muted: #727272;
  --line: #ece6d5;
  --danger: #b42318;
  --success: #16803a;
  font-family: Inter, "PingFang SC", "Microsoft YaHei", sans-serif;
  color: var(--ink);
  background: var(--cream);
}
* { box-sizing: border-box; }
body { margin: 0; min-height: 100vh; background: var(--cream); }
button, input, textarea, select { font: inherit; }
a { color: inherit; text-decoration: none; }
.admin-layout { display: grid; grid-template-columns: 236px 1fr; min-height: 100vh; }
.sidebar { display: flex; flex-direction: column; background: #fff; border-right: 1px solid var(--line); padding: 24px 16px; }
.brand { display: flex; align-items: center; gap: 12px; padding: 0 8px 24px; }
.brand strong, .brand small { display: block; }
.brand small { color: var(--muted); margin-top: 3px; }
.brand-mark { display: inline-grid; place-items: center; width: 38px; height: 38px; border-radius: 12px; background: var(--yellow); font-weight: 800; }
.nav-list { display: grid; gap: 6px; }
.nav-item { padding: 11px 14px; border-radius: 10px; color: #555; }
.nav-item:hover, .nav-item.active { background: #fff4bd; color: #5f4900; font-weight: 650; }
.sidebar-footer { display: flex; justify-content: space-between; align-items: center; margin-top: auto; padding: 18px 8px 0; border-top: 1px solid var(--line); color: var(--muted); }
.link-button { border: 0; background: transparent; color: #8b6b00; cursor: pointer; }
.main-content { min-width: 0; }
.page-header { min-height: 84px; padding: 24px 32px 18px; display: flex; align-items: center; justify-content: space-between; }
.page-header h1 { margin: 0; font-size: 26px; }
.page-body { padding: 0 32px 40px; }
.toolbar { display: flex; gap: 10px; margin-bottom: 16px; }
.search-input { min-width: 320px; }
input, textarea, select { width: 100%; border: 1px solid #d8d2c2; border-radius: 9px; background: #fff; padding: 10px 12px; outline: none; }
input:focus, textarea:focus, select:focus { border-color: var(--yellow-dark); box-shadow: 0 0 0 3px rgba(245, 208, 96, .25); }
.btn { display: inline-flex; justify-content: center; align-items: center; border: 1px solid transparent; border-radius: 9px; padding: 9px 15px; cursor: pointer; white-space: nowrap; }
.btn-primary { background: var(--yellow); color: #2d2400; font-weight: 700; }
.btn-primary:hover { background: #edc43d; }
.btn-secondary { background: #fff; border-color: #d8d2c2; }
.btn-ghost { background: transparent; border-color: transparent; color: #7b6410; }
.btn-danger { background: #fff; border-color: #f1b7b2; color: var(--danger); }
.btn-small { padding: 6px 10px; font-size: 13px; }
.btn-block { width: 100%; }
.table-card, .empty-panel { background: #fff; border: 1px solid var(--line); border-radius: 16px; overflow: hidden; box-shadow: 0 8px 28px rgba(59, 49, 20, .04); }
.data-table { width: 100%; border-collapse: collapse; }
.data-table th, .data-table td { padding: 14px 16px; text-align: left; border-bottom: 1px solid #f1ede3; vertical-align: middle; }
.data-table th { color: var(--muted); font-size: 13px; background: #fffdf7; }
.data-table tr:last-child td { border-bottom: 0; }
.subline { display: block; margin-top: 4px; max-width: 230px; overflow: hidden; text-overflow: ellipsis; color: #999; }
.badge { display: inline-flex; border-radius: 99px; padding: 4px 9px; font-size: 12px; }
.badge-success { background: #e6f6ea; color: var(--success); }
.badge-muted { background: #f0f0f0; color: #777; }
.badge-danger { background: #fff0ef; color: var(--danger); }
.empty-state, .empty-panel { padding: 64px 24px; text-align: center; color: var(--muted); }
.empty-panel.compact { padding: 28px 20px; }
.pagination { display: flex; justify-content: center; align-items: center; gap: 12px; padding-top: 18px; color: var(--muted); }
.login-body { display: grid; place-items: center; padding: 24px; }
.login-card { width: min(400px, 100%); padding: 34px; border-radius: 20px; background: #fff; box-shadow: 0 16px 48px rgba(63, 50, 8, .12); }
.login-brand { display: flex; justify-content: center; }
.login-card h1 { text-align: center; margin: 16px 0 6px; }
.login-card > p { text-align: center; color: var(--muted); margin: 0 0 24px; }
.form-stack { display: grid; gap: 16px; }
.form-stack label { display: grid; gap: 7px; font-size: 14px; font-weight: 600; }
.alert { padding: 10px 12px; margin-bottom: 16px; border-radius: 9px; }
.alert-error { background: #fff0ef; color: var(--danger); }
.alert-success { background: #edf9f0; color: var(--success); }
.form-card, .upload-card { padding: 24px; border: 1px solid var(--line); border-radius: 16px; background: #fff; box-shadow: 0 8px 28px rgba(59, 49, 20, .04); }
.form-grid { display: grid; grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 18px; }
.field { display: grid; align-content: start; gap: 7px; font-size: 14px; font-weight: 650; }
.field-wide { grid-column: 1 / -1; }
.field textarea { resize: vertical; line-height: 1.6; }
.checkbox-field { display: flex; align-items: center; gap: 9px; align-self: end; min-height: 42px; color: #555; font-size: 14px; }
.checkbox-field input { width: 18px; height: 18px; }
.form-actions, .inline-actions, .upload-heading, .detail-header, .section-heading { display: flex; align-items: center; gap: 10px; }
.form-actions { justify-content: flex-end; padding-top: 4px; }
.detail-header, .section-heading, .upload-heading { justify-content: space-between; }
.detail-header { margin-bottom: 16px; }
.detail-header h2, .section-heading h2, .upload-heading h2 { margin: 4px 0 0; }
.eyebrow { color: #9c7a0b; font-size: 11px; font-weight: 750; letter-spacing: .12em; text-transform: uppercase; }
.section-heading { margin: 34px 0 14px; }
.first-section { margin-top: 0; }
.table-spaced { margin-top: 16px; }
.compact-form-grid { display: grid; grid-template-columns: minmax(180px, .8fr) minmax(260px, 1.4fr) auto; align-items: end; gap: 14px; }
.tag-list { display: flex; flex-wrap: wrap; gap: 5px; }
.tag { display: inline-flex; padding: 3px 8px; border-radius: 99px; background: #fff4bd; color: #6f5700; font-size: 12px; }
.lesson-list { display: grid; gap: 12px; }
.lesson-card { overflow: hidden; border: 1px solid var(--line); border-radius: 14px; background: #fff; }
.lesson-card summary, .add-panel > summary { display: flex; align-items: center; gap: 10px; padding: 15px 18px; cursor: pointer; }
.lesson-card summary { border-bottom: 1px solid var(--line); }
.order-bubble { display: inline-grid; place-items: center; width: 27px; height: 27px; border-radius: 9px; background: var(--yellow); font-size: 12px; font-weight: 800; }
.lesson-media-state { margin-left: auto; color: var(--muted); font-size: 13px; }
.lesson-form { padding: 18px; }
.add-panel { margin-top: 14px; padding: 0; }
.add-panel .lesson-form { border-top: 1px solid var(--line); }
.callout { display: flex; gap: 8px; margin-bottom: 16px; padding: 13px 16px; border: 1px solid #ead88e; border-radius: 12px; background: #fff9d9; color: #655623; font-size: 14px; }
.inline-form { display: inline-block; margin-left: 5px; }
.danger-text { color: var(--danger); }
.narrow-card { max-width: 680px; }
.rename-form { display: grid; grid-template-columns: minmax(0, 1fr) auto; align-items: end; gap: 10px; margin: 18px 0; }
.form-help { color: var(--muted); font-size: 14px; line-height: 1.6; }
.drop-zone { display: grid; gap: 8px; margin: 20px 0 14px; padding: 30px; border: 2px dashed #d8c469; border-radius: 14px; background: #fffdf4; cursor: pointer; }
.drop-zone span { color: var(--muted); font-size: 14px; }
.drop-zone input { margin-top: 8px; padding: 0; border: 0; background: transparent; }
.progress-track { overflow: hidden; height: 8px; border-radius: 99px; background: #eee9dc; }
.progress-track span { display: block; width: 0; height: 100%; background: var(--yellow-dark); transition: width .2s ease; }
@media (max-width: 760px) {
  .admin-layout { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .nav-list { grid-template-columns: repeat(2, minmax(0, 1fr)); }
  .sidebar-footer { margin-top: 20px; }
  .page-header, .page-body { padding-left: 18px; padding-right: 18px; }
  .search-input { min-width: 0; }
  .table-card { overflow-x: auto; }
  .form-grid { grid-template-columns: 1fr; }
  .field-wide { grid-column: auto; }
  .detail-header, .section-heading, .upload-heading { align-items: flex-start; flex-direction: column; }
  .inline-actions { flex-wrap: wrap; }
  .callout { flex-direction: column; }
  .rename-form { grid-template-columns: 1fr; }
  .compact-form-grid { grid-template-columns: 1fr; }
}