/* Learning Platform Main Styles */

:root {
    --primary-color: #2563eb;
    --secondary-color: #1e40af;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --danger-color: #ef4444;
    --dark-color: #1f2937;
    --light-color: #f8fafc;
    --border-color: #e2e8f0;
    --text-dark: #334155;
    --text-light: #64748b;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--light-color);
}

/* Header Styles */
.header {
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    padding: 1rem 0;
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.header-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

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

.nav-menu a {
    color: white;
    text-decoration: none;
    transition: opacity 0.3s ease;
}

.nav-menu a:hover {
    opacity: 0.8;
}

/* Container */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

/* Cards */
.card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    padding: 2rem;
    margin-bottom: 2rem;
}

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

.card-title {
    font-size: 1.5rem;
    color: var(--dark-color);
    margin-bottom: 0.5rem;
}

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

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

.form-control {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
    transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.form-control:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.1);
}

.form-select {
    width: 100%;
    padding: 0.75rem;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 1rem;
    background-color: white;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 4px;
    text-decoration: none;
    font-size: 1rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s ease;
    text-align: center;
}

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

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

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

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

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

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

/* Tables */
.table {
    width: 100%;
    border-collapse: collapse;
    margin-top: 1rem;
}

.table th,
.table td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

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

.table tr:hover {
    background-color: rgba(37, 99, 235, 0.05);
}

/* Dashboard Grid */
.dashboard-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.stat-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    text-align: center;
}

.stat-number {
    font-size: 3rem;
    font-weight: bold;
    color: var(--primary-color);
    margin-bottom: 0.5rem;
}

.stat-label {
    font-size: 1.1rem;
    color: var(--text-light);
}

/* Video Player */
.video-container {
    position: relative;
    width: 100%;
    padding-bottom: 56.25%; /* 16:9 aspect ratio */
    background-color: #000;
    border-radius: 8px;
    overflow: hidden;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
}

/* Course Grid */
.course-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.course-card {
    background: white;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    overflow: hidden;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.course-card-image {
    width: 100%;
    height: 200px;
    background-color: var(--light-color);
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--text-light);
}

.course-card-content {
    padding: 1.5rem;
}

.course-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: var(--dark-color);
}

.course-description {
    color: var(--text-light);
    margin-bottom: 1rem;
    font-size: 0.9rem;
}

.course-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 1rem;
    font-size: 0.875rem;
    color: var(--text-light);
}

/* Alerts */
.alert {
    padding: 1rem;
    border-radius: 4px;
    margin-bottom: 1rem;
}

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

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

.alert-warning {
    background-color: #fef3c7;
    border: 1px solid #fde68a;
    color: #92400e;
}

/* Sidebar */
.sidebar {
    width: 250px;
    background: white;
    height: 100vh;
    position: fixed;
    left: 0;
    top: 0;
    box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
    z-index: 999;
    padding-top: 80px;
}

.sidebar-menu {
    list-style: none;
    padding: 0;
}

.sidebar-menu li {
    border-bottom: 1px solid var(--border-color);
}

.sidebar-menu a {
    display: block;
    padding: 1rem 1.5rem;
    color: var(--text-dark);
    text-decoration: none;
    transition: background-color 0.3s ease;
}

.sidebar-menu a:hover,
.sidebar-menu a.active {
    background-color: var(--primary-color);
    color: white;
}

.main-content {
    margin-left: 250px;
    padding-top: 80px;
    min-height: 100vh;
}

/* Progress Bar */
.progress {
    width: 100%;
    height: 8px;
    background-color: var(--border-color);
    border-radius: 4px;
    overflow: hidden;
}

.progress-bar {
    height: 100%;
    background-color: var(--success-color);
    transition: width 0.3s ease;
}

/* Loading Spinner */
.spinner {
    border: 4px solid var(--border-color);
    border-top: 4px 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); }
}

/* Responsive Design */
@media (max-width: 768px) {
    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.3s ease;
    }
    
    .sidebar.show {
        transform: translateX(0);
    }
    
    .main-content {
        margin-left: 0;
    }
    
    .header-content {
        padding: 0 1rem;
    }
    
    .container {
        padding: 1rem;
    }
    
    .dashboard-grid {
        grid-template-columns: 1fr;
    }
    
    .course-grid {
        grid-template-columns: 1fr;
    }
    
    .nav-menu {
        flex-direction: column;
        gap: 1rem;
    }
}

/* Utility Classes */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }
.mb-1 { margin-bottom: 0.5rem; }
.mb-2 { margin-bottom: 1rem; }
.mb-3 { margin-bottom: 1.5rem; }
.mt-1 { margin-top: 0.5rem; }
.mt-2 { margin-top: 1rem; }
.mt-3 { margin-top: 1.5rem; }
.d-flex { display: flex; }
.justify-between { justify-content: space-between; }
.align-center { align-items: center; }
.gap-1 { gap: 0.5rem; }
.gap-2 { gap: 1rem; }
.w-100 { width: 100%; }
.h-100 { height: 100%; }

/* Badge Styles */
.badge {
    display: inline-block;
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
    font-weight: 500;
    line-height: 1;
    text-align: center;
    white-space: nowrap;
    vertical-align: baseline;
    border-radius: 0.375rem;
}

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

.badge-secondary {
    color: white;
    background-color: var(--text-light);
}

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

.badge-warning {
    color: #212529;
    background-color: var(--warning-color);
}

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

/* Button Size Variants */
.btn-sm {
    padding: 0.375rem 0.75rem;
    font-size: 0.875rem;
    border-radius: 0.25rem;
}

.btn-lg {
    padding: 0.75rem 1.5rem;
    font-size: 1.125rem;
    border-radius: 0.5rem;
}