/* Estilos generales */
:root {
    --primary-color: #3498db;
    --secondary-color: #2c3e50;
    --success-color: #27ae60;
    --warning-color: #f39c12;
    --danger-color: #e74c3c;
    --light-color: #ecf0f1;
    --dark-color: #34495e;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f8f9fa;
}

/* Header */
.navbar-brand {
    font-weight: bold;
    font-size: 1.5rem;
}

.user-avatar {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    object-fit: cover;
}

/* Auth pages */
.auth-container {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
}

.auth-card {
    background: white;
    border-radius: 10px;
    padding: 2rem;
    box-shadow: 0 10px 40px rgba(0, 0, 0, 0.1);
    width: 100%;
    max-width: 450px;
}

/* Dashboard */
.sidebar {
    min-height: calc(100vh - 56px);
    background: var(--secondary-color);
    padding: 0;
}

.sidebar .nav-link {
    color: #bdc3c7;
    padding: 15px 20px;
    border-left: 3px solid transparent;
}

.sidebar .nav-link:hover {
    color: white;
    background: rgba(255, 255, 255, 0.1);
}

.sidebar .nav-link.active {
    color: white;
    background: rgba(255, 255, 255, 0.2);
    border-left-color: var(--primary-color);
}

/* Course cards */
.course-card {
    transition: transform 0.3s, box-shadow 0.3s;
    border: none;
    border-radius: 10px;
    overflow: hidden;
}

.course-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.1);
}

.course-thumbnail {
    height: 200px;
    object-fit: cover;
}

.course-badge {
    position: absolute;
    top: 10px;
    right: 10px;
}

.price-tag {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--success-color);
}

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

/* Progress bars */
.progress-circle {
    width: 60px;
    height: 60px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    background: conic-gradient(var(--primary-color) 75%, #eee 0%);
    position: relative;
}

.progress-circle::before {
    content: attr(data-progress) '%';
    position: absolute;
    background: white;
    width: 50px;
    height: 50px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
}

/* Video player */
.video-container {
    position: relative;
    padding-bottom: 56.25%; /* 16:9 */
    height: 0;
    overflow: hidden;
}

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

/* Payment QR */
.qr-container {
    text-align: center;
    padding: 20px;
    background: white;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.1);
}

.qr-image {
    max-width: 300px;
    margin: 20px auto;
}

/* Notifications */
.notification-badge {
    position: relative;
}

.notification-badge::after {
    content: attr(data-count);
    position: absolute;
    top: -5px;
    right: -5px;
    background: var(--danger-color);
    color: white;
    border-radius: 50%;
    width: 20px;
    height: 20px;
    font-size: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
}

/* Responsive */
@media (max-width: 768px) {
    .sidebar {
        min-height: auto;
        margin-bottom: 20px;
    }
    
    .auth-card {
        margin: 20px;
        padding: 1.5rem;
    }
    
    .course-thumbnail {
        height: 150px;
    }
}