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

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-color: #1f2937;
    --light-color: #f3f4f6;
    --white: #ffffff;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f5f5f5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

/* Header */
header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: var(--white);
    padding: 1rem 0;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 600;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 2rem;
}

nav a {
    color: var(--white);
    text-decoration: none;
    font-weight: 500;
    transition: opacity 0.3s;
}

nav a:hover {
    opacity: 0.8;
}

/* Cards */
.card {
    background: var(--white);
    border-radius: 10px;
    padding: 1.5rem;
    box-shadow: 0 2px 10px rgba(0,0,0,0.08);
    margin-bottom: 1.5rem;
}

.card-header {
    border-bottom: 2px solid var(--light-color);
    padding-bottom: 1rem;
    margin-bottom: 1rem;
}

.card-header h2 {
    color: var(--dark-color);
    font-size: 1.5rem;
}

/* Forms */
.form-group {
    margin-bottom: 1.5rem;
}

label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark-color);
}

input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
input[type="date"],
input[type="tel"],
input[type="file"],
textarea,
select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid #d1d5db;
    border-radius: 6px;
    font-size: 1rem;
    transition: border-color 0.3s;
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--primary-color);
}

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

.checkbox-group {
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.checkbox-group input[type="checkbox"] {
    width: auto;
    cursor: pointer;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 6px;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    text-decoration: none;
    transition: all 0.3s;
    text-align: center;
}

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

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

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

.btn-success:hover {
    background: #059669;
}

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

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

.btn-danger:hover {
    background: #dc2626;
}

.btn-sm {
    padding: 0.5rem 1rem;
    font-size: 0.875rem;
}

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

table {
    width: 100%;
    border-collapse: collapse;
    background: var(--white);
}

th, td {
    padding: 1rem;
    text-align: left;
    border-bottom: 1px solid var(--light-color);
}

th {
    background: var(--light-color);
    font-weight: 600;
    color: var(--dark-color);
}

tr:hover {
    background: #fafafa;
}

/* 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-color), var(--secondary-color));
    color: var(--white);
    padding: 1.5rem;
    border-radius: 10px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.1);
}

.stat-card h3 {
    font-size: 0.9rem;
    opacity: 0.9;
    margin-bottom: 0.5rem;
}

.stat-card .value {
    font-size: 2rem;
    font-weight: 700;
}

.stat-card.success {
    background: linear-gradient(135deg, var(--success-color), #059669);
}

.stat-card.warning {
    background: linear-gradient(135deg, var(--warning-color), #d97706);
}

.stat-card.danger {
    background: linear-gradient(135deg, var(--danger-color), #dc2626);
}

/* Badges */
.badge {
    display: inline-block;
    padding: 0.25rem 0.75rem;
    border-radius: 20px;
    font-size: 0.875rem;
    font-weight: 500;
}

.badge-success {
    background: #d1fae5;
    color: #065f46;
}

.badge-warning {
    background: #fed7aa;
    color: #92400e;
}

.badge-danger {
    background: #fee2e2;
    color: #991b1b;
}

.badge-primary {
    background: #dbeafe;
    color: #1e40af;
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: 6px;
    margin-bottom: 1rem;
}

.alert-success {
    background: #d1fae5;
    color: #065f46;
    border-left: 4px solid var(--success-color);
}

.alert-error {
    background: #fee2e2;
    color: #991b1b;
    border-left: 4px solid var(--danger-color);
}

.alert-warning {
    background: #fed7aa;
    color: #92400e;
    border-left: 4px solid var(--warning-color);
}

/* Login Page */
.login-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
}

.login-box {
    background: var(--white);
    padding: 2.5rem;
    border-radius: 10px;
    box-shadow: 0 10px 40px rgba(0,0,0,0.2);
    width: 100%;
    max-width: 400px;
}

.login-box h2 {
    text-align: center;
    margin-bottom: 2rem;
    color: var(--dark-color);
}

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

.grid-3 {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 1.5rem;
}

/* Image Preview */
.image-preview {
    max-width: 200px;
    max-height: 200px;
    margin-top: 0.5rem;
    border-radius: 6px;
    border: 1px solid var(--light-color);
}

/* Actions */
.actions {
    display: flex;
    gap: 0.5rem;
}

/* Responsive */
@media (max-width: 768px) {
    .grid-2,
    .grid-3 {
        grid-template-columns: 1fr;
    }
    
    nav ul {
        flex-direction: column;
        gap: 1rem;
    }
    
    .stats-grid {
        grid-template-columns: 1fr;
    }
    
    .table-container {
        overflow-x: scroll;
    }
}

/* Loading Spinner */
.spinner {
    border: 3px solid var(--light-color);
    border-top: 3px solid var(--primary-color);
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 20px auto;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}