:root {
    --bg-color: #f3f4f6;
    --sidebar-bg: #1f2937;
    --primary: #2563eb;
    --text-main: #111827;
    --text-muted: #6b7280;
    --border: #e5e7eb;
}
* { box-sizing: border-box; margin: 0; padding: 0; font-family: system-ui, sans-serif; }
body { background-color: var(--bg-color); color: var(--text-main); }
.hidden { display: none !important; }

/* Auth Screen */
.auth-container { display: flex; height: 100vh; align-items: center; justify-content: center; background: #e2e8f0; }
.auth-box { background: white; padding: 40px; border-radius: 8px; box-shadow: 0 10px 25px rgba(0,0,0,0.1); width: 350px; text-align: center; }
.auth-box input { width: 100%; padding: 12px; margin: 10px 0; border: 1px solid var(--border); border-radius: 4px; }

/* Buttons */
button { padding: 10px 16px; border: none; border-radius: 4px; cursor: pointer; font-weight: 600; }
.btn-primary { background: var(--primary); color: white; }
.btn-secondary { background: #4b5563; color: white; }
.btn-danger { background: #dc2626; color: white; }
.btn-small { padding: 5px 10px; font-size: 12px; }

/* Main App Layout */
.app-layout { display: flex; height: 100vh; }
.sidebar { width: 250px; background: var(--sidebar-bg); color: white; display: flex; flex-direction: column; padding: 20px 0; }
.brand { font-size: 20px; font-weight: bold; padding: 0 20px 20px 20px; border-bottom: 1px solid #374151; margin-bottom: 10px; }
.nav-item { background: none; color: #9ca3af; text-align: left; padding: 15px 20px; font-size: 15px; border-radius: 0; display: block; width: 100%; }
.nav-item:hover, .nav-item.active { background: #374151; color: white; }
.nav-item i { width: 25px; }
.nav-header { padding: 15px 20px 5px 20px; font-size: 12px; text-transform: uppercase; color: #6b7280; font-weight: bold; }
.logout-btn { margin: auto 20px 0 20px; }

/* Content Area */
.content-area { flex: 1; padding: 30px; overflow-y: auto; background: white; border-radius: 12px 0 0 12px; box-shadow: -5px 0 15px rgba(0,0,0,0.05); }
.header-row { display: flex; justify-content: space-between; align-items: center; margin-bottom: 20px; }
.add-bar { display: flex; gap: 10px; width: 50%; }
.add-bar input { flex: 1; padding: 10px; border: 1px solid var(--border); border-radius: 4px; }

/* Tables */
.data-table { width: 100%; border-collapse: collapse; margin-top: 15px; }
.data-table th, .data-table td { padding: 12px; border-bottom: 1px solid var(--border); text-align: left; }
.data-table th { background: #f9fafb; font-weight: 600; color: var(--text-muted); }
.action-group { display: flex; gap: 5px; }

/* Alerts & UI Elements */
.alert-banner { background: #fef3c7; color: #92400e; padding: 15px; border-radius: 8px; margin-bottom: 20px; display: flex; align-items: center; justify-content: space-between; border: 1px solid #fcd34d; }
.box-outline { border: 1px solid var(--border); padding: 20px; border-radius: 8px; margin-top: 15px; }
.card { border: 1px solid var(--border); padding: 20px; border-radius: 8px; box-shadow: 0 2px 5px rgba(0,0,0,0.05); }
.full-width { width: 100%; padding: 10px; margin: 15px 0; }

/* Modal */
.modal { position: fixed; top: 0; left: 0; width: 100%; height: 100%; background: rgba(0,0,0,0.5); display: flex; align-items: center; justify-content: center; }
.modal-content { background: white; padding: 30px; border-radius: 8px; width: 400px; }
.modal-actions { display: flex; justify-content: flex-end; gap: 10px; }