:root {
    --primary: #2563eb;
    --primary-hover: #1d4ed8;
    --primary-light: #eff6ff;
    --success: #059669;
    --danger: #dc2626;
    --text: #1e293b;
    --text-muted: #64748b;
    --bg: #f8fafc;
    --card-bg: #ffffff;
    --radius: 12px;
    --shadow: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', -apple-system, sans-serif;
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.6;
}

.container {
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem;
}

/* Navbar */
.admin-nav {
    background: white;
    padding: 1rem 2rem;
    box-shadow: 0 1px 3px rgba(0,0,0,0.1);
    position: sticky;
    top: 0;
    z-index: 1000;
}
.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}
.nav-brand {
    font-weight: 800;
    font-size: 1.25rem;
    color: var(--primary);
}
.nav-links {
    display: flex;
    gap: 1.5rem;
    align-items: center;
}
.nav-links a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.95rem;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    transition: all 0.2s;
}
.nav-links a:hover, .nav-links a.active {
    color: var(--primary);
    background: var(--primary-light);
}
.logout-link {
    background: #fee2e2;
    color: #991b1b;
    border: none;
    padding: 0.5rem 1rem;
    border-radius: 8px;
    cursor: pointer;
    font-weight: 600;
}

/* Header */
header {
    margin-bottom: 2.5rem;
    text-align: center;
}

h1 { font-weight: 800; font-size: 2.25rem; margin-bottom: 0.5rem; letter-spacing: -0.025em; }
.subtitle { color: var(--text-muted); font-size: 1.1rem; }

/* Cards */
.card {
    background-color: var(--card-bg);
    border-radius: var(--radius);
    padding: 2.5rem;
    box-shadow: var(--shadow);
    margin-bottom: 2rem;
}

/* Form Styles */
.form-section { margin-bottom: 2.5rem; }
.form-section h3 { margin-bottom: 1.5rem; font-weight: 700; display: flex; align-items: center; gap: 0.5rem; }

.form-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 1.5rem;
}

.form-group.full-width { grid-column: span 2; }

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    font-size: 0.875rem;
    color: var(--text);
}

input, select, textarea {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    font-size: 1rem;
    transition: all 0.2s;
    background: #fcfcfc;
}

input:focus, select:focus, textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
    background: white;
}

textarea { min-height: 100px; resize: vertical; }

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.75rem 1.5rem;
    border-radius: 10px;
    font-weight: 700;
    cursor: pointer;
    border: none;
    transition: all 0.2s;
    font-size: 1rem;
    text-decoration: none;
}

.btn-primary { background-color: var(--primary); color: white; }
.btn-primary:hover { background-color: var(--primary-hover); transform: translateY(-1px); box-shadow: 0 10px 15px -3px rgba(37, 99, 235, 0.2); }

.btn-block { width: 100%; }

.badge {
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.75rem;
    font-weight: 700;
    text-transform: uppercase;
    background: var(--primary-light);
    color: var(--primary);
}

.alert {
    padding: 1rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
    display: none;
    font-weight: 600;
}

.hidden { display: none; }

/* QR View */
#qr-container img {
    max-width: 250px;
    height: auto;
}

@media (max-width: 768px) {
    .form-grid { grid-template-columns: 1fr; }
    .form-group.full-width { grid-column: span 1; }
    .nav-links { display: none; } /* Could add a hamburger menu if needed */
}