:root {
  color-scheme: light;
  font-family: "Segoe UI", "Microsoft YaHei", sans-serif;
  --bg: #f4f7fb;
  --card: #ffffff;
  --line: #e5ebf3;
  --text: #1f2937;
  --muted: #6b7280;
  --primary: #155eef;
  --primary-soft: #e9f0ff;
  --danger: #dc2626;
  --danger-soft: #fee2e2;
}

* { box-sizing: border-box; }

body { margin: 0; background: var(--bg); color: var(--text); }

.app-shell { min-height: 100vh; display: grid; grid-template-columns: 260px 1fr; }

.sidebar { background: #0f172a; color: #fff; padding: 24px; }

.brand { display: flex; gap: 12px; align-items: center; margin-bottom: 36px; }
.brand-mark { width: 44px; height: 44px; border-radius: 14px; display: grid; place-items: center; background: #2563eb; font-weight: 800; }
.brand small { display: block; margin-top: 4px; color: #cbd5e1; }

.nav-item {
  width: 100%; border: 0; border-radius: 12px; background: transparent;
  color: #cbd5e1; cursor: pointer; display: block; margin-bottom: 8px;
  padding: 12px 14px; text-align: left; font-size: 15px;
}
.nav-item.active, .nav-item:hover { background: rgba(255, 255, 255, 0.1); color: #fff; }

.content { padding: 28px; }

.topbar { display: flex; justify-content: space-between; align-items: center; margin-bottom: 22px; }

h1, h2, h3 { margin: 0; }

.topbar p, .card p { color: var(--muted); }

.card { background: var(--card); border: 1px solid var(--line); border-radius: 18px; box-shadow: 0 10px 30px rgba(15, 23, 42, 0.06); padding: 20px; }

.login-card { max-width: 460px; }
.login-card code { background: var(--primary-soft); color: var(--primary); padding: 2px 6px; border-radius: 6px; }

label { display: block; color: var(--muted); margin: 14px 0; }
label.check { display: flex; align-items: center; gap: 8px; margin: 8px 0; }
label.check input[type="checkbox"] { width: auto; margin: 0; }

input, select, textarea {
  width: 100%; border: 1px solid var(--line); border-radius: 10px;
  font: inherit; margin-top: 6px; padding: 10px 12px;
}

button {
  background: #f3f4f6; border: 1px solid var(--line); border-radius: 8px;
  padding: 8px 14px; cursor: pointer; font: inherit;
}
button:hover { background: #e5e7eb; }
button.primary { background: var(--primary); border: 0; color: white; padding: 11px 18px; border-radius: 10px; }
button.primary:hover { background: #0f4ec9; }
button.danger { background: var(--danger-soft); color: var(--danger); border-color: #fecaca; }
button.danger:hover { background: #fecaca; }

.hidden { display: none !important; }

.stats { display: grid; grid-template-columns: repeat(4, minmax(0, 1fr)); gap: 14px; margin-bottom: 18px; }
.stat-card { background: var(--card); border: 1px solid var(--line); border-radius: 16px; padding: 18px; }
.stat-card strong { display: block; font-size: 30px; margin-top: 8px; }

.toolbar { align-items: center; display: flex; justify-content: space-between; margin-bottom: 14px; gap: 12px; }

.table { width: 100%; border-collapse: collapse; overflow: hidden; }
.table th, .table td { border-bottom: 1px solid var(--line); padding: 12px; text-align: left; vertical-align: middle; }
.table th { color: var(--muted); font-weight: 600; }

.tag {
  background: var(--primary-soft); border-radius: 999px; color: var(--primary);
  display: inline-block; padding: 4px 10px; font-size: 13px;
}
.tag.muted { background: #f3f4f6; color: var(--muted); }

.user-box { display: flex; align-items: center; gap: 10px; }
.user-box .user-name { font-weight: 600; }

.message { color: var(--muted); min-height: 24px; }
.empty { padding: 22px; text-align: center; color: var(--muted); }

.modal-mask {
  position: fixed; inset: 0; background: rgba(15, 23, 42, 0.4);
  display: grid; place-items: center; z-index: 999;
}
.modal {
  width: min(720px, 92vw); max-height: 86vh; overflow-y: auto;
  background: var(--card); border-radius: 16px; box-shadow: 0 20px 50px rgba(15, 23, 42, 0.18);
}
.modal-head { display: flex; justify-content: space-between; align-items: center; padding: 16px 22px; border-bottom: 1px solid var(--line); }
.modal-head h3 { margin: 0; }
.modal-head .close { background: transparent; border: 0; font-size: 22px; cursor: pointer; color: var(--muted); }
.modal-body { padding: 18px 22px; }
.modal-foot { display: flex; gap: 10px; align-items: center; padding: 14px 22px; border-top: 1px solid var(--line); }

.perm-matrix { display: grid; grid-template-columns: repeat(2, 1fr); gap: 12px; max-height: 50vh; overflow-y: auto; }
.perm-group { border: 1px solid var(--line); border-radius: 12px; padding: 12px; }
.perm-group legend { padding: 0 6px; color: var(--primary); font-weight: 600; }
.perm-group code { color: var(--muted); font-size: 12px; }

@media (max-width: 860px) {
  .app-shell { grid-template-columns: 1fr; }
  .sidebar { position: static; }
  .stats { grid-template-columns: 1fr; }
  .perm-matrix { grid-template-columns: 1fr; }
}