/*
 * Shared shell + components for every admin page (Dashboard, Problems,
 * Users, Admins). Consolidated here instead of duplicated inline <style>
 * blocks per page, since all four share the same sidebar/layout/table/
 * card/button system -- a tweak to one should apply everywhere.
 */

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
  min-height: 100vh;
}

.admin-shell {
  display: flex;
  min-height: 100vh;
}

/* ---------- Sidebar ---------- */

.admin-sidebar {
  width: 220px;
  flex-shrink: 0;
  background: var(--panel);
  border-right: 1px solid var(--border);
  display: flex;
  flex-direction: column;
  position: sticky;
  top: 0;
  height: 100vh;
}

.admin-sidebar-brand {
  padding: 20px 20px 16px;
  font-weight: 700;
  font-size: 16px;
  display: flex;
  align-items: baseline;
  gap: 8px;
}
.admin-sidebar-brand .accent { color: var(--accent); }
.admin-sidebar-brand .admin-tag {
  font-size: 10px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 2px 6px;
}

.admin-sidebar-nav {
  display: flex;
  flex-direction: column;
  padding: 8px 12px;
  gap: 2px;
  flex: 1;
}
.admin-sidebar-nav a {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 9px 12px;
  border-radius: 8px;
  color: var(--muted);
  text-decoration: none;
  font-size: 13.5px;
  font-weight: 500;
  border-left: 3px solid transparent;
}
.admin-sidebar-nav a:hover { background: var(--panel-2); color: var(--text); }
.admin-sidebar-nav a.active {
  background: var(--panel-2);
  color: var(--text);
  border-left-color: var(--accent);
  font-weight: 700;
}
.admin-sidebar-nav a .icon { font-size: 15px; width: 18px; text-align: center; }

.admin-sidebar-footer {
  padding: 14px 16px;
  border-top: 1px solid var(--border);
}
.admin-sidebar-footer .fallback-toggle {
  font-size: 11px;
  color: var(--muted);
  cursor: pointer;
  margin-top: 10px;
  text-decoration: underline;
  text-underline-offset: 2px;
  background: none;
  border: none;
  padding: 0;
}
.admin-token-fallback {
  display: none;
  margin-top: 8px;
  gap: 6px;
  flex-direction: column;
}
.admin-token-fallback.open { display: flex; }
.admin-token-fallback input {
  background: var(--bg);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 6px;
  padding: 6px 8px;
  font-size: 12px;
  width: 100%;
}

/* ---------- Main content ---------- */

.admin-main {
  flex: 1;
  padding: 32px 40px;
  max-width: 1160px;
}

.admin-page-header {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 28px;
  gap: 16px;
}
.admin-page-header h1 { margin: 0 0 4px; font-size: 24px; }
.admin-page-header .subtitle { color: var(--muted); font-size: 13.5px; margin: 0; }
.admin-page-header .actions { display: flex; gap: 10px; flex-shrink: 0; }

/* ---------- Buttons ---------- */

.btn {
  border: 1px solid var(--border);
  background: var(--panel-2);
  color: var(--text);
  border-radius: 8px;
  padding: 8px 16px;
  font-size: 13px;
  font-weight: 600;
  cursor: pointer;
  white-space: nowrap;
}
.btn:hover { border-color: var(--accent); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #0f1115; }
.btn-primary:hover { filter: brightness(1.08); }
.btn-danger { background: transparent; border-color: var(--red); color: var(--red); }
.btn-danger:hover { background: rgba(227,86,74,0.12); }
.btn-success { background: transparent; border-color: var(--green); color: var(--green); }
.btn-success:hover { background: rgba(56,193,114,0.12); }
.btn-sm { padding: 5px 11px; font-size: 12px; }

/* ---------- Cards / sections ---------- */

.card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px 20px;
}
.card + .card { margin-top: 16px; }

.stat-grid { display: grid; grid-template-columns: repeat(auto-fit, minmax(140px, 1fr)); gap: 14px; margin-bottom: 24px; }
.stat-card {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 18px;
}
.stat-card .num { font-size: 28px; font-weight: 700; line-height: 1.1; }
.stat-card .label { font-size: 12px; color: var(--muted); margin-top: 6px; }

.section-title {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--muted);
  font-weight: 700;
  margin: 0 0 12px;
}

/* ---------- Tabs ---------- */

.tabs { display: flex; gap: 4px; margin-bottom: 20px; border-bottom: 1px solid var(--border); }
.tabs button {
  background: none;
  border: none;
  color: var(--muted);
  font-size: 13.5px;
  font-weight: 600;
  padding: 10px 4px;
  margin-right: 20px;
  cursor: pointer;
  border-bottom: 2px solid transparent;
  position: relative;
  top: 1px;
}
.tabs button:hover { color: var(--text); }
.tabs button.active { color: var(--text); border-bottom-color: var(--accent); }

/* ---------- Tables ---------- */

.admin-table-wrap { overflow-x: auto; }
table.admin-table { width: 100%; border-collapse: collapse; font-size: 13px; }
table.admin-table th {
  text-align: left;
  color: var(--muted);
  font-weight: 600;
  font-size: 10.5px;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0 12px 10px;
  border-bottom: 1px solid var(--border);
}
table.admin-table td {
  padding: 11px 12px;
  border-bottom: 1px solid var(--border);
  vertical-align: middle;
}
table.admin-table tr:last-child td { border-bottom: none; }
table.admin-table tr.clickable { cursor: pointer; }
table.admin-table tr.clickable:hover td { background: var(--panel-2); }

/* ---------- Pills / badges ---------- */

.pill {
  display: inline-block;
  padding: 2px 9px;
  border-radius: 20px;
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.02em;
}
.pill.tier-paid { background: rgba(56,193,114,0.15); color: var(--green); }
.pill.tier-free { background: rgba(138,147,166,0.15); color: var(--muted); }
.pill.difficulty-easy { background: rgba(56,193,114,0.15); color: var(--green); }
.pill.difficulty-medium { background: rgba(217,164,65,0.18); color: var(--amber); }
.pill.difficulty-hard { background: rgba(227,86,74,0.15); color: var(--red); }
.pill.track-sql { background: rgba(79,140,255,0.15); color: var(--accent); }
.pill.track-python { background: rgba(56,193,114,0.15); color: var(--green); }
.pill.track-pandas { background: rgba(217,164,65,0.18); color: var(--amber); }
.pill.track-numpy { background: rgba(227,86,74,0.15); color: var(--red); }
.tag-pill { background: var(--panel-2); color: var(--muted); border-radius: 6px; padding: 1px 7px; font-size: 11px; margin-right: 4px; }

/* ---------- Filter row ---------- */

.filter-row { display: flex; gap: 8px; margin-bottom: 16px; }
.filter-row input, .filter-row select {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 13px;
}
.filter-row input { flex: 1; }

.category-pills { display: flex; gap: 8px; margin-bottom: 16px; flex-wrap: wrap; }
.category-pill {
  background: var(--panel);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 20px;
  padding: 6px 14px;
  font-size: 13px;
  cursor: pointer;
}
.category-pill.active { border-color: var(--accent); background: var(--panel-2); }
.category-pill .count { color: var(--muted); margin-left: 4px; }
.category-pill.clear-pill { color: var(--muted); border-style: dashed; }

/* ---------- Empty / loading / error states ---------- */

.empty-note { color: var(--muted); font-size: 13px; padding: 24px 0; text-align: center; }
.loading-dots { color: var(--muted); font-size: 13px; padding: 24px 0; text-align: center; }
.error-banner {
  background: rgba(227,86,74,0.1);
  border: 1px solid rgba(227,86,74,0.4);
  color: var(--red);
  border-radius: 8px;
  padding: 10px 14px;
  font-size: 13px;
}

/* ---------- Drafts (Problems > Pending) ---------- */

.draft-card { background: var(--panel); border: 1px solid var(--border); border-radius: 10px; padding: 16px; margin-bottom: 14px; }
.draft-card h3 { margin: 0 0 6px 0; font-size: 15px; }
.draft-meta { font-size: 12px; color: var(--muted); margin-bottom: 10px; }
.draft-actions { display: flex; gap: 8px; margin-top: 10px; }
.schema-block {
  font-family: ui-monospace, "SF Mono", Menlo, Consolas, monospace;
  font-size: 12px;
  background: var(--panel-2);
  border: 1px solid var(--border);
  border-radius: 6px;
  padding: 8px 10px;
  white-space: pre-wrap;
  margin-top: 6px;
}

/* ---------- Live problem rows ---------- */

.live-row { display: flex; justify-content: space-between; align-items: center; padding: 12px 0; border-bottom: 1px solid var(--border); }
.live-row:last-child { border-bottom: none; }
.live-row .title { font-size: 13.5px; margin-bottom: 3px; }
.live-row .meta { font-size: 11.5px; color: var(--muted); }

/* ---------- History drill-down / pie chart ---------- */

.history-panel { background: var(--panel-2); border: 1px solid var(--border); border-radius: 10px; padding: 16px; margin: 8px 0 14px; }
.history-row { display: flex; justify-content: space-between; padding: 6px 0; border-bottom: 1px solid var(--border); font-size: 13px; }
.history-row:last-child { border-bottom: none; }
.pass-mark { color: var(--green); }
.fail-mark { color: var(--red); }

.pie-chart-wrap { display: flex; align-items: center; gap: 20px; }
.legend { display: flex; flex-direction: column; gap: 6px; font-size: 13px; }
.legend-row { display: flex; align-items: center; gap: 8px; }
.legend-swatch { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }
.legend-count { color: var(--muted); margin-left: 4px; }

/* ---------- Admins page form ---------- */

.admin-form-row { display: flex; gap: 8px; align-items: center; margin-top: 14px; flex-wrap: wrap; }
.admin-form-row input {
  background: var(--panel-2);
  border: 1px solid var(--border);
  color: var(--text);
  border-radius: 8px;
  padding: 8px 12px;
  font-size: 13px;
  flex: 1;
  min-width: 220px;
}

@media (max-width: 800px) {
  .admin-shell { flex-direction: column; }
  .admin-sidebar { width: 100%; height: auto; position: static; flex-direction: row; align-items: center; overflow-x: auto; }
  .admin-sidebar-nav { flex-direction: row; }
  .admin-sidebar-footer { display: none; }
  .admin-main { padding: 20px; }
}