:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --secondary: #10b981;
    --secondary-hover: #059669;
    --bg-color: #f3f4f6;
    --sidebar-bg: #111827;
    --sidebar-text: #9ca3af;
    --sidebar-text-hover: #ffffff;
    --card-bg: #ffffff;
    --text-main: #1f2937;
    --text-muted: #6b7280;
    --border-color: #e5e7eb;
    --danger: #ef4444;
    --danger-hover: #dc2626;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --radius-md: 0.5rem;
    --radius-lg: 1rem;
}

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

body {
    font-family: 'Sarabun', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-main);
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    width: 260px;
    background-color: var(--sidebar-bg);
    color: var(--sidebar-text);
    display: flex;
    flex-direction: column;
    transition: all 0.3s ease;
    box-shadow: var(--shadow-lg);
    z-index: 10;
}

.sidebar .logo {
    padding: 2rem 1.5rem;
    display: flex;
    align-items: center;
    gap: 1rem;
    border-bottom: 1px solid rgba(255, 255, 255, 0.1);
}

.sidebar .logo i {
    font-size: 2rem;
    color: var(--primary);
}

.sidebar .logo h2 {
    color: #fff;
    font-size: 1.25rem;
    line-height: 1.2;
    font-weight: 600;
}

.sidebar nav {
    flex: 1;
    padding: 1.5rem 0;
}

.sidebar nav ul {
    list-style: none;
}

.sidebar nav ul li a {
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 1rem 1.5rem;
    color: var(--sidebar-text);
    text-decoration: none;
    font-weight: 500;
    transition: all 0.2s ease;
    border-left: 4px solid transparent;
}

.sidebar nav ul li a:hover, .sidebar nav ul li a.active {
    color: var(--sidebar-text-hover);
    background-color: rgba(255, 255, 255, 0.05);
    border-left-color: var(--primary);
}

.sidebar nav ul li a i {
    width: 20px;
    text-align: center;
    font-size: 1.1rem;
}

/* Main Content */
.main-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

header {
    background-color: var(--card-bg);
    padding: 1.5rem 2rem;
    box-shadow: var(--shadow-sm);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

header h1 {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--text-main);
}

.content-wrapper {
    padding: 2rem;
    flex: 1;
}

/* Cards */
.card {
    background-color: var(--card-bg);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    padding: 1.5rem;
    margin-bottom: 1.5rem;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    box-shadow: var(--shadow-lg);
}

.card-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1.5rem;
    border-bottom: 1px solid var(--border-color);
    padding-bottom: 1rem;
}

.card-header h2 {
    font-size: 1.25rem;
    font-weight: 600;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.6rem 1.2rem;
    border-radius: var(--radius-md);
    font-size: 0.95rem;
    font-weight: 500;
    cursor: pointer;
    border: none;
    transition: all 0.2s ease;
    text-decoration: none;
    font-family: inherit;
}

.btn-primary {
    background-color: var(--primary);
    color: white;
}

.btn-primary:hover {
    background-color: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-secondary {
    background-color: var(--secondary);
    color: white;
}

.btn-secondary:hover {
    background-color: var(--secondary-hover);
    transform: translateY(-1px);
}

.btn-danger {
    background-color: var(--danger);
    color: white;
}

.btn-danger:hover {
    background-color: var(--danger-hover);
}

/* Forms */
.form-group {
    margin-bottom: 1rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--text-main);
}

.form-control {
    width: 100%;
    padding: 0.6rem 1rem;
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    font-size: 1rem;
    font-family: inherit;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(79, 70, 229, 0.2);
}

/* Tables */
.table-responsive {
    overflow-x: auto;
}

.table {
    width: 100%;
    border-collapse: collapse;
    text-align: left;
}

.table th, .table td {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
}

.table th {
    background-color: #f9fafb;
    font-weight: 600;
    color: var(--text-muted);
    text-transform: uppercase;
    font-size: 0.85rem;
    letter-spacing: 0.05em;
}

.table tbody tr {
    transition: background-color 0.2s ease;
}

.table tbody tr:hover {
    background-color: #f9fafb;
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: var(--radius-md);
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.75rem;
}

.alert-success {
    background-color: #d1fae5;
    color: #065f46;
    border: 1px solid #a7f3d0;
}

.alert-danger {
    background-color: #fee2e2;
    color: #991b1b;
    border: 1px solid #fecaca;
}

/* Dashboard Stats */
.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-hover) 100%);
    color: white;
    padding: 1.5rem;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: 1.5rem;
    transition: transform 0.3s ease;
}

.stat-card:hover {
    transform: translateY(-5px);
}

.stat-card.secondary {
    background: linear-gradient(135deg, var(--secondary) 0%, var(--secondary-hover) 100%);
}

.stat-card.accent {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.stat-icon {
    background-color: rgba(255, 255, 255, 0.2);
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.75rem;
}

.stat-info h3 {
    font-size: 0.9rem;
    font-weight: 500;
    opacity: 0.9;
    margin-bottom: 0.25rem;
}

.stat-info p {
    font-size: 1.8rem;
    font-weight: 700;
}