:root {
  --bg: #f4f6fb;
  --card: #ffffff;
  --ink: #1f2330;
  --ink-soft: #6b7280;
  --line: #e6e9f0;
  --accent: #4f46e5;
  --accent-soft: #eef0ff;
  --danger: #e1466b;
  --shadow: 0 6px 22px rgba(31, 35, 48, 0.08);
  --radius: 14px;
}

* { box-sizing: border-box; }

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "PingFang SC",
    "Microsoft YaHei", Roboto, Helvetica, Arial, sans-serif;
  background: var(--bg);
  color: var(--ink);
  line-height: 1.6;
}

/* Top bar */
.topbar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 18px 28px;
  background: linear-gradient(120deg, #4f46e5, #6d5ef0);
  color: #fff;
  box-shadow: var(--shadow);
}
.brand { display: flex; align-items: center; gap: 14px; }
.logo { font-size: 34px; }
.brand-text h1 { margin: 0; font-size: 22px; font-weight: 700; }
.brand-text .sub { margin: 0; font-size: 13px; opacity: 0.9; }

.admin-btn {
  background: rgba(255, 255, 255, 0.18);
  border: 1px solid rgba(255, 255, 255, 0.45);
  color: #fff;
  padding: 9px 16px;
  border-radius: 10px;
  cursor: pointer;
  font-size: 14px;
  transition: background 0.15s;
}
.admin-btn:hover { background: rgba(255, 255, 255, 0.3); }

/* Layout */
.container { max-width: 1080px; margin: 0 auto; padding: 28px 20px 60px; }
.section-title { display: flex; align-items: baseline; gap: 12px; margin: 8px 0 18px; }
.section-title h2 { margin: 0; font-size: 18px; }
.hint { color: var(--ink-soft); font-size: 13px; }

/* Grid of cards */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
  gap: 16px;
}
.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 18px;
  text-align: center;
  cursor: pointer;
  box-shadow: var(--shadow);
  transition: transform 0.15s, box-shadow 0.15s, border-color 0.15s;
  user-select: none;
}
.card:hover { transform: translateY(-4px); border-color: var(--accent); }
.card .emoji { font-size: 38px; display: block; margin-bottom: 8px; }
.card .name { font-size: 16px; font-weight: 600; }
.card .meta { font-size: 12px; color: var(--ink-soft); margin-top: 4px; }

/* Modal */
.modal {
  position: fixed; inset: 0;
  background: rgba(20, 24, 40, 0.45);
  display: flex; align-items: center; justify-content: center;
  padding: 20px; z-index: 50;
}
.modal.hidden, .hidden { display: none !important; }
.modal-card {
  background: var(--card);
  width: min(720px, 100%);
  max-height: 82vh;
  border-radius: 18px;
  display: flex; flex-direction: column;
  box-shadow: 0 20px 60px rgba(0,0,0,0.25);
  overflow: hidden;
}
.modal-head {
  display: flex; align-items: center; justify-content: space-between;
  padding: 16px 20px; border-bottom: 1px solid var(--line);
}
.crumb { font-size: 15px; color: var(--ink-soft); }
.crumb b { color: var(--ink); }
.crumb .sep { margin: 0 8px; opacity: 0.5; }
.icon-btn {
  border: none; background: var(--accent-soft); color: var(--accent);
  width: 34px; height: 34px; border-radius: 9px; cursor: pointer; font-size: 16px;
}
.icon-btn:hover { background: #e2e5ff; }
.modal-body { padding: 20px; overflow-y: auto; }

/* Breadcrumb clickable */
.crumb a { color: var(--accent); text-decoration: none; cursor: pointer; }
.crumb a:hover { text-decoration: underline; }

/* Folder / file rows */
.row {
  display: flex; align-items: center; justify-content: space-between;
  padding: 13px 14px; border: 1px solid var(--line); border-radius: 11px;
  margin-bottom: 10px; transition: border-color 0.15s, background 0.15s;
}
.row:hover { border-color: var(--accent); background: var(--accent-soft); }
.row .left { display: flex; align-items: center; gap: 10px; }
.row .ico { font-size: 20px; }
.row .title { font-weight: 500; }
.row .size { font-size: 12px; color: var(--ink-soft); margin-left: 6px; }

.btn {
  border: 1px solid var(--line); background: #fff; color: var(--ink);
  padding: 8px 14px; border-radius: 9px; cursor: pointer; font-size: 14px;
}
.btn:hover { border-color: var(--accent); }
.btn.small { padding: 7px 12px; font-size: 13px; }
.btn.primary { background: var(--accent); color: #fff; border-color: var(--accent); width: 100%; padding: 12px; font-size: 15px; font-weight: 600; }
.btn.primary:hover { background: #4338ca; }
.btn.ghost { background: transparent; }
.btn.danger { color: var(--danger); border-color: #f3c0cd; }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.empty { text-align: center; color: var(--ink-soft); padding: 40px 0; }
.spinner { display: inline-block; width: 18px; height: 18px; border: 3px solid var(--line); border-top-color: var(--accent); border-radius: 50%; animation: spin 0.8s linear infinite; }
@keyframes spin { to { transform: rotate(360deg); } }

/* Admin panel */
.admin-panel {
  position: fixed; top: 0; right: 0; height: 100vh; width: min(380px, 92vw);
  background: var(--card); box-shadow: -10px 0 40px rgba(0,0,0,0.18);
  padding: 22px; overflow-y: auto; z-index: 60;
}
.admin-head { display: flex; align-items: center; justify-content: space-between; margin-bottom: 8px; }
.admin-head h3 { margin: 0; }
.admin-section { margin: 18px 0; }
.field-label { display: block; font-size: 13px; font-weight: 600; margin-bottom: 7px; }
.text-input, .file-input {
  width: 100%; padding: 10px 12px; border: 1px solid var(--line);
  border-radius: 9px; font-size: 14px; background: #fff; color: var(--ink);
}
.text-input:focus { outline: none; border-color: var(--accent); }
.checkbox { display: flex; align-items: center; gap: 7px; font-size: 13px; margin-top: 8px; color: var(--ink-soft); }
.token-row { display: flex; gap: 8px; }
.token-row .text-input { flex: 1; }
.token-status { font-size: 13px; margin: 8px 0 0; }
.token-status.ok { color: #1a9d63; }
.token-status.bad { color: var(--danger); }
.upload-log { margin-top: 16px; font-size: 13px; }
.upload-log .item { padding: 6px 0; border-bottom: 1px dashed var(--line); }
.upload-log .item.ok { color: #1a9d63; }
.upload-log .item.err { color: var(--danger); }

/* Toast */
.toast {
  position: fixed; bottom: 28px; left: 50%; transform: translateX(-50%);
  background: #1f2330; color: #fff; padding: 11px 20px; border-radius: 10px;
  font-size: 14px; z-index: 80; box-shadow: var(--shadow);
}
.toast.err { background: var(--danger); }

/* 年级筛选 */
.filterbar {
  display: flex; align-items: center; flex-wrap: wrap; gap: 8px;
  padding: 12px 14px; margin-bottom: 18px;
  background: var(--card); border: 1px solid var(--line); border-radius: 12px;
  box-shadow: var(--shadow);
}
.filter-label { font-size: 13px; font-weight: 600; margin-right: 2px; }
.chip {
  border: 1px solid var(--line); background: #fff; color: var(--ink-soft);
  padding: 6px 14px; border-radius: 999px; cursor: pointer; font-size: 13px;
}
.chip:hover { border-color: var(--accent); }
.chip.active { background: var(--accent); border-color: var(--accent); color: #fff; font-weight: 600; }
.filter-tip { font-size: 12px; color: var(--ink-soft); margin-left: auto; }

/* 科目卡片：未分类 */
.card-unclassified { border-style: dashed; }
.card-unclassified .name { color: var(--ink-soft); }

/* 年级徽章 */
.badge {
  font-size: 12px; padding: 2px 8px; border-radius: 999px; margin-left: 6px;
  background: var(--accent-soft); color: var(--accent); white-space: nowrap;
}
.badge-none { background: #f1f2f6; color: var(--ink-soft); }
.crumb-tag {
  font-size: 12px; padding: 2px 8px; border-radius: 999px; margin-left: 8px;
  background: #fff; color: var(--accent); border: 1px solid var(--accent);
}
.row-actions { display: flex; gap: 8px; align-items: center; flex-shrink: 0; }
.row .left { flex-wrap: wrap; }

/* 归类行内编辑 */
.row-edit { display: block; background: var(--accent-soft); }
.edit-grid { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; }
.edit-name { font-weight: 500; width: 100%; word-break: break-all; }

/* 待上传清单 */
.bulk-row { display: flex; gap: 8px; }
.text-input.small { flex: 1; padding: 8px 10px; font-size: 13px; }
.text-input.tiny { padding: 6px 8px; font-size: 12px; }
.review-box {
  border: 1px solid var(--line); border-radius: 11px; padding: 12px;
  margin: 14px 0; background: #fafbff;
}
.review-head {
  display: flex; align-items: center; justify-content: space-between;
  font-size: 13px; margin-bottom: 10px;
}
.review-head .warn { color: #c2410c; }
.review-list { max-height: 320px; overflow-y: auto; }
.rev-row {
  display: grid; grid-template-columns: 1fr 92px 96px 1fr 30px;
  gap: 6px; align-items: center; padding: 6px 0;
  border-bottom: 1px dashed var(--line);
}
.rev-row.rev-warn .rev-name { color: #c2410c; }
.rev-name {
  font-size: 12px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap;
}
.rev-row .text-input.tiny { width: 100%; min-width: 0; }

@media (max-width: 520px) {
  .topbar { padding: 14px 18px; }
  .brand-text .sub { display: none; }
  .rev-row { grid-template-columns: 1fr 30px; }
  .rev-row .text-input.tiny { grid-column: span 2; }
}