:root {
  --bg: #f4f5f7; --panel: #ffffff; --side: #1c2333; --side-active: #2c355a;
  --text: #1f2430; --muted: #6b7280; --brand: #2f6fed; --danger: #d64545;
  --border: #e3e6ec; --radius: 10px;
}
* { box-sizing: border-box; margin: 0; }
body { font-family: "PingFang TC", "Microsoft JhengHei", system-ui, sans-serif; background: var(--bg); color: var(--text); font-size: 15px; }

/* layout */
.layout { display: flex; min-height: 100vh; }
.sidebar { width: 210px; background: var(--side); color: #cdd3e1; padding: 18px 12px; flex-shrink: 0; }
.sidebar h1 { font-size: 17px; color: #fff; padding: 0 10px 16px; }
.sidebar a { display: block; color: inherit; text-decoration: none; padding: 9px 12px; border-radius: 8px; margin-bottom: 2px; font-size: 14px; }
.sidebar a.active, .sidebar a:hover { background: rgba(255,255,255,.1); color: #fff; }
.sidebar .user { margin-top: 18px; border-top: 1px solid rgba(255,255,255,.15); padding: 12px 10px 0; font-size: 13px; }
.sidebar button { margin-top: 8px; width: 100%; background: none; border: 1px solid rgba(255,255,255,.3); color: #cdd3e1; border-radius: 8px; padding: 6px; cursor: pointer; }
.main { flex: 1; padding: 24px; min-width: 0; }
.main h2 { font-size: 20px; margin-bottom: 16px; }

/* toolbar & table */
.toolbar { display: flex; gap: 10px; margin-bottom: 14px; flex-wrap: wrap; }
.toolbar input { flex: 1; min-width: 160px; max-width: 320px; padding: 8px 12px; border: 1px solid var(--border); border-radius: 8px; }
.btn { background: var(--brand); color: #fff; border: 0; border-radius: 8px; padding: 8px 16px; cursor: pointer; font-size: 14px; }
.btn.secondary { background: #fff; color: var(--text); border: 1px solid var(--border); }
.btn.danger { background: var(--danger); }
.panel { background: var(--panel); border: 1px solid var(--border); border-radius: var(--radius); overflow: auto; }
table { width: 100%; border-collapse: collapse; font-size: 14px; }
th, td { text-align: left; padding: 10px 14px; border-bottom: 1px solid var(--border); white-space: nowrap; }
th { color: var(--muted); font-weight: 500; background: #fafbfc; }
tr:hover td { background: #f7f9ff; }
.empty { padding: 30px; text-align: center; color: var(--muted); }
.pager { display: flex; gap: 8px; align-items: center; padding: 12px; color: var(--muted); font-size: 13px; }

/* modal & form */
.modal-bg { position: fixed; inset: 0; background: rgba(20,24,35,.45); display: none; align-items: center; justify-content: center; z-index: 50; }
.modal-bg.open { display: flex; }
.modal { background: #fff; border-radius: 12px; width: min(520px, 92vw); max-height: 88vh; overflow: auto; padding: 22px; }
.modal h3 { margin-bottom: 14px; font-size: 17px; }
.field { margin-bottom: 12px; }
.field label { display: block; font-size: 13px; color: var(--muted); margin-bottom: 4px; }
.field input, .field select, .field textarea { width: 100%; padding: 8px 10px; border: 1px solid var(--border); border-radius: 8px; font: inherit; }
.modal .actions { display: flex; gap: 10px; justify-content: flex-end; margin-top: 16px; }
.error-msg { color: var(--danger); font-size: 13px; margin-top: 8px; min-height: 18px; }

/* login */
.login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center; background: var(--side); }
.login-card { background: #fff; border-radius: 14px; padding: 34px; width: min(380px, 92vw); }
.login-card h1 { font-size: 20px; margin-bottom: 20px; text-align: center; }

@media (max-width: 760px) {
  .layout { flex-direction: column; }
  .sidebar { width: 100%; display: flex; flex-wrap: wrap; align-items: center; gap: 4px; padding: 10px; }
  .sidebar h1 { padding: 0 8px; width: 100%; }
  .sidebar .user { margin: 0; border: 0; padding: 0 8px; }
  .main { padding: 14px; }
}