/* assets/style.css */
:root {
    --primary: #0d6efd;
    --secondary: #6c757d;
    --success: #198754;
    --danger: #dc3545;
    --light: #f8f9fa;
    --dark: #212529;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    margin: 0;
    padding: 0;
    background-color: #f0f2f5;
    color: var(--dark);
}

.navbar {
    background-color: white;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.brand {
    font-weight: bold;
    font-size: 1.2rem;
    color: var(--primary);
}

.container {
    padding: 1rem;
    max-width: 800px;
    margin: 0 auto;
}

.view {
    display: none;
    padding: 1rem;
}

.view.active {
    display: block;
}

.card {
    background: white;
    border-radius: 8px;
    padding: 1.5rem;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    margin-bottom: 1rem;
}

.login-card {
    max-width: 400px;
    margin: 2rem auto;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
}

.form-group input {
    width: 100%;
    padding: 0.5rem;
    border: 1px solid #ced4da;
    border-radius: 4px;
}

.btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 1rem;
}

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

.stats-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.stat-card h3 { margin: 0; font-size: 0.9rem; color: var(--secondary); }
.stat-card p { margin: 0.5rem 0 0; font-size: 1.5rem; font-weight: bold; color: var(--primary); }

.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 1rem;
}

.course-card {
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
    cursor: pointer;
    transition: transform 0.2s;
}

.course-card:hover {
    transform: translateY(-2px);
}

.course-thumb {
    height: 140px;
    background: #eee;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #aaa;
}

.course-info {
    padding: 1rem;
}

.course-title {
    font-weight: bold;
    margin-bottom: 0.5rem;
}

#offline-indicator {
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: var(--danger);
    color: white;
    text-align: center;
    padding: 0.5rem;
    font-size: 0.8rem;
}

/* Admin Styles */
.tabs {
    display: flex;
    border-bottom: 2px solid #ddd;
    margin-bottom: 1rem;
}

.tab-btn {
    padding: 0.5rem 1rem;
    border: none;
    background: none;
    cursor: pointer;
    font-size: 1rem;
    color: var(--secondary);
}

.tab-btn.active {
    border-bottom: 2px solid var(--primary);
    color: var(--primary);
    font-weight: bold;
}

.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
}

.data-table {
    width: 100%;
    border-collapse: collapse;
    background: white;
    box-shadow: 0 2px 4px rgba(0,0,0,0.05);
}

.data-table th, .data-table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid #eee;
}

.data-table th {
    background: #f8f9fa;
    font-weight: bold;
}

/* Modal */
.modal {
    display: none;
    position: fixed;
    top: 0; left: 0; width: 100%; height: 100%;
    background: rgba(0,0,0,0.5);
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal.active {
    display: flex;
}

.modal-content {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    width: 90%;
    max-width: 500px;
}