:root {
  --bg: #0f172a;
  --panel: #111827;
  --card: #1f2937;
  --text: #e5e7eb;
  --muted: #9ca3af;
  --primary: #3b82f6;
  --danger: #ef4444;
  --ok: #22c55e;
  --border: #374151;
}

* { box-sizing: border-box; }
body {
  margin: 0;
  font-family: "Segoe UI", "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--bg);
  color: var(--text);
}

.hidden { display: none !important; }

.login-wrap {
  min-height: 100vh;
  display: grid;
  place-items: center;
  padding: 20px;
}
.login-card {
  width: 100%;
  max-width: 420px;
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 28px;
}
.login-card h1 { margin: 0 0 8px; }
.sub, .hint { color: var(--muted); font-size: 14px; }

#main-view { display: grid; grid-template-columns: 240px 1fr; min-height: 100vh; }
.sidebar {
  background: var(--panel);
  border-right: 1px solid var(--border);
  padding: 20px 16px;
  display: flex;
  flex-direction: column;
}
.brand { font-weight: 700; margin-bottom: 20px; }
.nav-btn {
  width: 100%;
  text-align: left;
  background: transparent;
  color: var(--text);
  border: 0;
  padding: 12px 14px;
  border-radius: 10px;
  margin-bottom: 6px;
  cursor: pointer;
}
.nav-btn.active, .nav-btn:hover { background: var(--card); }
.user-box { margin-top: auto; font-size: 14px; color: var(--muted); }

.content { padding: 24px; }
.page-header { display: flex; justify-content: space-between; align-items: center; gap: 12px; flex-wrap: wrap; }
.actions { display: flex; gap: 8px; }

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: 12px;
  margin-bottom: 16px;
}
.stat-card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
}
.stat-card .num { font-size: 28px; font-weight: 700; margin-top: 8px; }

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 16px;
  margin-top: 12px;
}
.form-card { max-width: 520px; display: grid; gap: 8px; }

input, select, button {
  font: inherit;
  border-radius: 10px;
  border: 1px solid var(--border);
  background: #0b1220;
  color: var(--text);
  padding: 10px 12px;
}
button { cursor: pointer; background: var(--primary); border-color: var(--primary); }
button.danger { background: var(--danger); border-color: var(--danger); }
button.ghost { background: transparent; border-color: var(--border); }
.role-select { padding: 6px 8px; font-size: 13px; }

.table-wrap { overflow: auto; border: 1px solid var(--border); border-radius: 12px; margin-top: 12px; }
table { width: 100%; border-collapse: collapse; min-width: 900px; }
th, td { padding: 10px 12px; border-bottom: 1px solid var(--border); text-align: left; font-size: 14px; }
th { background: #0b1220; }
.low { color: #fbbf24; }

.scan-row { display: grid; grid-template-columns: 1fr auto; gap: 8px; }
.item-info { color: var(--muted); min-height: 24px; }
.reader { margin-top: 12px; max-width: 420px; }

.modal {
  position: fixed; inset: 0; background: rgba(0,0,0,.55);
  display: grid; place-items: center; padding: 16px; z-index: 20;
}
.modal-card {
  width: 100%; max-width: 520px; background: var(--panel);
  border: 1px solid var(--border); border-radius: 14px; padding: 20px;
}
.modal-actions { display: flex; justify-content: flex-end; gap: 8px; margin-top: 8px; }

.toast {
  position: fixed; right: 20px; bottom: 20px; background: #111827;
  border: 1px solid var(--border); padding: 12px 16px; border-radius: 10px; z-index: 30;
}

@media (max-width: 900px) {
  #main-view { grid-template-columns: 1fr; }
  .sidebar { border-right: 0; border-bottom: 1px solid var(--border); }
  nav { display: grid; grid-template-columns: repeat(3, 1fr); gap: 6px; }
}