* { box-sizing: border-box; margin: 0; padding: 0; font-family: Arial, sans-serif; }
body { background: #f4f6f8; color: #1f2937; }
.app { display: flex; min-height: calc(100vh - 56px); }
.sidebar { width: 250px; background: #111827; color: #fff; transition: width .2s ease; min-height: calc(100vh - 56px); }
.sidebar.collapsed { width: 72px; }
.sidebar-top { display: flex; align-items: center; justify-content: space-between; padding: 16px; border-bottom: 1px solid #374151; }
.logo { font-weight: bold; font-size: 18px; }
.collapse-btn { border: none; background: #374151; color: #fff; padding: 8px 10px; border-radius: 6px; cursor: pointer; }
.menu { display: flex; flex-direction: column; padding: 12px; gap: 8px; }
.menu a { color: #e5e7eb; text-decoration: none; padding: 10px 12px; border-radius: 6px; }
.menu a:hover { background: #1f2937; }
.content { flex: 1; padding: 24px; }
.card { background: #fff; border-radius: 10px; padding: 20px; box-shadow: 0 1px 4px rgba(0,0,0,.08); margin-bottom: 18px; }
h1 { margin-bottom: 16px; }
form .grid { display: grid; grid-template-columns: repeat(2,minmax(0,1fr)); gap: 12px; }
label { font-size: 14px; margin-bottom: 6px; display: block; }
input, select, textarea { width: 100%; padding: 10px; border: 1px solid #d1d5db; border-radius: 8px; }
button { background: #2563eb; color: #fff; border: none; padding: 10px 14px; border-radius: 8px; cursor: pointer; }
button.secondary { background: #374151; }
table { width: 100%; border-collapse: collapse; background: #fff; }
th, td { padding: 10px; border-bottom: 1px solid #e5e7eb; text-align: left; }
.alert { padding: 10px; border-radius: 8px; margin-bottom: 10px; }
.alert.success { background: #dcfce7; color: #166534; }
.alert.error { background: #fee2e2; color: #991b1b; }
.site-footer { height: 56px; display: flex; align-items: center; justify-content: center; background: #111827; color: #fff; }
.login-wrap { min-height: 100vh; display: flex; align-items: center; justify-content: center; }
.login-box { width: 360px; background: #fff; border-radius: 12px; padding: 24px; box-shadow: 0 2px 8px rgba(0,0,0,.1); }
.items-table input { min-width: 120px; }
.total-box { text-align: right; font-size: 20px; font-weight: bold; margin-top: 10px; }
@media (max-width: 900px) {
  form .grid { grid-template-columns: 1fr; }
}