:root {
  color-scheme: dark;
  --bg: #070a12;
  --panel: #0f1420;
  --panel-2: #141b2a;
  --line: rgba(151, 174, 219, 0.15);
  --text: #f5f8ff;
  --muted: #8f9bb3;
  --cyan: #20d9ff;
  --blue: #4d7cff;
  --green: #35e1aa;
  --danger: #ff6d82;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  min-width: 320px;
  min-height: 100vh;
  color: var(--text);
  background:
    radial-gradient(circle at 85% -10%, rgba(23, 93, 205, 0.24), transparent 35%),
    var(--bg);
  font-family: Inter, "PingFang SC", "Microsoft YaHei", system-ui, sans-serif;
}
button, input { font: inherit; }
button { color: inherit; }

/* display:grid/flex 会覆盖原生 hidden，必须强制隐藏 */
[hidden] { display: none !important; }

.admin-shell { display: grid; grid-template-columns: 248px minmax(0, 1fr); min-height: 100vh; }
.admin-sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 28px 20px;
  border-right: 1px solid var(--line);
  background: rgba(8, 11, 19, 0.9);
  backdrop-filter: blur(18px);
  display: flex;
  flex-direction: column;
}
.admin-brand {
  display: flex;
  align-items: center;
  gap: 11px;
  color: var(--text);
  font-size: 17px;
  font-weight: 750;
  text-decoration: none;
}
.admin-brand img { width: 36px; height: 36px; border-radius: 11px; }
.admin-nav { display: grid; gap: 8px; margin-top: 44px; }
.nav-item {
  border: 1px solid transparent;
  border-radius: 12px;
  padding: 12px 14px;
  text-align: left;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
}
.nav-item:hover, .nav-item.active {
  color: var(--text);
  background: linear-gradient(135deg, rgba(32, 217, 255, 0.12), rgba(77, 124, 255, 0.12));
  border-color: rgba(32, 217, 255, 0.18);
}
.logout-btn {
  margin-top: auto;
  border: 1px solid var(--line);
  border-radius: 12px;
  padding: 10px 12px;
  background: transparent;
  color: var(--muted);
  cursor: pointer;
  text-align: left;
}
.logout-btn:hover { color: var(--text); border-color: rgba(32, 217, 255, 0.28); }
.back-link { margin-top: 12px; color: var(--muted); text-decoration: none; font-size: 14px; }
.back-link:hover { color: var(--cyan); }

.login-gate {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 24px;
  background:
    radial-gradient(circle at 20% 10%, rgba(32, 217, 255, 0.16), transparent 28%),
    radial-gradient(circle at 80% 0%, rgba(77, 124, 255, 0.18), transparent 32%),
    var(--bg);
}
.login-card {
  width: min(100%, 420px);
  display: grid;
  gap: 14px;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: linear-gradient(145deg, rgba(20, 27, 42, 0.96), rgba(10, 14, 24, 0.96));
  box-shadow: 0 24px 60px rgba(0, 0, 0, 0.28);
}
.login-card img { width: 48px; height: 48px; border-radius: 14px; }
.login-card h1 { margin: 0; font-size: 28px; letter-spacing: -0.04em; }
.login-card p { margin: 0; color: var(--muted); line-height: 1.6; }
.login-error { color: var(--danger); font-size: 13px; }

.admin-main { width: 100%; max-width: 1440px; padding: 34px clamp(22px, 4vw, 58px) 64px; }
.admin-header { display: flex; justify-content: space-between; align-items: flex-end; gap: 24px; margin-bottom: 28px; }
.eyebrow { margin: 0 0 8px; color: var(--cyan); font-size: 11px; letter-spacing: 0.2em; }
.admin-header h1 { margin: 0; font-size: clamp(28px, 4vw, 42px); letter-spacing: -0.04em; }
.account { display: grid; gap: 4px; text-align: right; }
.account span { color: var(--muted); font-size: 12px; }
.account strong { font-size: 14px; font-weight: 600; }

.notice {
  margin-bottom: 18px;
  padding: 12px 15px;
  border: 1px solid rgba(53, 225, 170, 0.25);
  border-radius: 12px;
  color: var(--green);
  background: rgba(53, 225, 170, 0.08);
}
.notice.error { color: var(--danger); border-color: rgba(255, 109, 130, 0.25); background: rgba(255, 109, 130, 0.08); }

.panel { display: none; }
.panel.active { display: block; }
.range-switch { display: flex; gap: 8px; margin-bottom: 18px; }
.range-switch button {
  border: 1px solid var(--line);
  border-radius: 999px;
  padding: 8px 15px;
  background: var(--panel);
  color: var(--muted);
  cursor: pointer;
}
.range-switch button.active { color: #031119; border-color: transparent; background: var(--cyan); font-weight: 700; }

.metric-grid { display: grid; grid-template-columns: repeat(3, minmax(0, 1fr)); gap: 16px; }
.metric-card, .dashboard-card {
  border: 1px solid var(--line);
  border-radius: 18px;
  background: linear-gradient(145deg, rgba(20, 27, 42, 0.94), rgba(12, 17, 28, 0.94));
  box-shadow: 0 20px 55px rgba(0, 0, 0, 0.18);
}
.metric-card { padding: 22px; display: grid; gap: 8px; }
.metric-card span, .metric-card small { color: var(--muted); }
.metric-card strong { font-size: clamp(32px, 5vw, 50px); letter-spacing: -0.05em; }
.metric-card small { font-size: 12px; }

.dashboard-card { padding: 22px; }
.chart-card { margin-top: 16px; }
.card-heading { display: flex; align-items: center; justify-content: space-between; gap: 20px; margin-bottom: 20px; }
.card-heading h2, .help-card h2 { margin: 0; font-size: 18px; }
.card-heading p { margin: 5px 0 0; color: var(--muted); font-size: 13px; }
.traffic-chart {
  min-height: 220px;
  display: flex;
  align-items: flex-end;
  gap: 10px;
  padding-top: 18px;
  overflow-x: auto;
}
.chart-column { min-width: 42px; flex: 1; display: grid; justify-items: center; gap: 8px; }
.chart-bars { height: 160px; width: 100%; display: flex; align-items: flex-end; justify-content: center; gap: 4px; }
.chart-bar { width: min(16px, 38%); min-height: 3px; border-radius: 5px 5px 2px 2px; background: linear-gradient(180deg, var(--cyan), var(--blue)); }
.chart-bar.visitors { background: linear-gradient(180deg, var(--green), #168b7d); opacity: 0.8; }
.chart-column small { color: var(--muted); font-size: 10px; white-space: nowrap; }

.dashboard-columns { display: grid; grid-template-columns: 1.15fr 0.85fr; gap: 16px; margin-top: 16px; }
.rank-list { display: grid; gap: 2px; }
.rank-row { display: grid; grid-template-columns: minmax(0, 1fr) auto; gap: 16px; padding: 11px 0; border-top: 1px solid var(--line); }
.rank-row:first-child { border-top: 0; }
.rank-row span { min-width: 0; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; color: #d9e2f7; font-size: 13px; }
.rank-row strong { color: var(--cyan); font-size: 13px; }
.empty-row { padding: 28px 0; color: var(--muted); text-align: center; }

.settings-card { max-width: 900px; }
.switch { display: flex; align-items: center; gap: 9px; color: var(--muted); cursor: pointer; }
.switch input { position: absolute; opacity: 0; }
.switch span { position: relative; width: 42px; height: 24px; border-radius: 999px; background: #283247; transition: 0.2s; }
.switch span::after { content: ""; position: absolute; top: 3px; left: 3px; width: 18px; height: 18px; border-radius: 50%; background: white; transition: 0.2s; }
.switch input:checked + span { background: var(--green); }
.switch input:checked + span::after { transform: translateX(18px); }
.form-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 18px; }
.field { display: grid; gap: 8px; }
.field.full { grid-column: 1 / -1; }
.field span { font-size: 13px; color: #dce6fa; }
.field small { color: var(--muted); font-size: 11px; }
.field input {
  width: 100%;
  border: 1px solid var(--line);
  border-radius: 11px;
  padding: 12px 13px;
  color: var(--text);
  background: #0a0f1a;
  outline: none;
}
.field input:focus { border-color: rgba(32, 217, 255, 0.6); box-shadow: 0 0 0 3px rgba(32, 217, 255, 0.08); }
.form-actions { display: flex; align-items: center; justify-content: flex-end; gap: 18px; margin-top: 24px; }
.updated-text { margin-right: auto; color: var(--muted); font-size: 12px; }
.primary-btn { border: 0; border-radius: 11px; padding: 11px 18px; color: #041116; background: var(--cyan); font-weight: 750; cursor: pointer; }
.primary-btn:disabled { opacity: 0.55; cursor: wait; }
.help-card { max-width: 900px; margin-top: 16px; }
.help-card ul { margin: 14px 0 0; padding-left: 20px; color: var(--muted); line-height: 1.9; font-size: 13px; }

@media (max-width: 860px) {
  .admin-shell { display: block; }
  .admin-sidebar { position: static; width: 100%; height: auto; padding: 16px 18px; flex-direction: row; align-items: center; gap: 16px; }
  .admin-brand span, .back-link { display: none; }
  .admin-nav { margin: 0; display: flex; }
  .nav-item { padding: 9px 11px; }
  .admin-main { padding-top: 24px; }
  .metric-grid, .dashboard-columns { grid-template-columns: 1fr; }
}
@media (max-width: 560px) {
  .admin-header { align-items: flex-start; }
  .account { display: none; }
  .form-grid { grid-template-columns: 1fr; }
  .field.full { grid-column: auto; }
  .card-heading { align-items: flex-start; flex-direction: column; }
}