:root {
    --primary-blue: #2563eb;
    --dark-blue: #1e40af;
    --light-blue: #3b82f6;
    --bg-dark: #0f172a;
    --bg-light: #1e293b;
    --text-light: #f1f5f9;
    --text-gray: #94a3b8;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 100%);
    color: var(--text-light);
    min-height: 100vh;
    padding-top: 70px;
}

/* Navigation */
.navbar {
    background: rgba(15, 23, 42, 0.95) !important;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid rgba(37, 99, 235, 0.3);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
}

.navbar-brand {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--primary-blue) !important;
}

.navbar-brand i {
    color: var(--light-blue);
}

.nav-link {
    color: var(--text-light) !important;
    margin: 0 10px;
    transition: color 0.3s;
}

.nav-link:hover {
    color: var(--light-blue) !important;
}

.nav-link.btn-primary {
    background: var(--primary-blue);
    border: none;
    padding: 8px 20px;
    border-radius: 5px;
}

.nav-link.btn-primary:hover {
    background: var(--dark-blue);
    color: white !important;
}

/* Hero Section */
.hero-section {
    padding: 80px 0;
    text-align: center;
    background: linear-gradient(135deg, rgba(37, 99, 235, 0.1) 0%, rgba(30, 64, 175, 0.1) 100%);
    border-radius: 15px;
    margin: 30px 0;
}

.hero-section h1 {
    font-size: 3rem;
    font-weight: bold;
    margin-bottom: 20px;
    background: linear-gradient(135deg, var(--light-blue), var(--primary-blue));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-section p {
    font-size: 1.2rem;
    color: var(--text-gray);
    margin-bottom: 30px;
}

/* Cards */
.card {
    background: rgba(30, 41, 59, 0.8);
    border: 1px solid rgba(37, 99, 235, 0.2);
    border-radius: 10px;
    transition: transform 0.3s, box-shadow 0.3s;
    color: var(--text-light);

}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(37, 99, 235, 0.3);
    border-color: var(--primary-blue);
}

.card-img-top {
    border-radius: 10px 10px 0 0;
    height: 200px;
    object-fit: cover;
}

.card-title {
    color: var(--light-blue);
    font-weight: 600;
}

.card-text {
    color: var(--text-gray);
}

/* Buttons */
.btn-primary {
    background: var(--primary-blue);
    border: none;
    padding: 10px 25px;
    border-radius: 5px;
    transition: background 0.3s;
}

.btn-primary:hover {
    background: var(--dark-blue);
}

.btn-outline-primary {
    border-color: var(--primary-blue);
    color: var(--primary-blue);
}

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

/* Forms */
.form-control, .form-select {
    background: rgba(30, 41, 59, 0.8);
    border: 1px solid rgba(37, 99, 235, 0.3);
    color: var(--text-light);
    padding: 12px;
    border-radius: 5px;
}

.form-control:focus, .form-select:focus {
    background: rgba(30, 41, 59, 0.9);
    border-color: var(--primary-blue);
    color: var(--text-light);
    box-shadow: 0 0 0 0.2rem rgba(37, 99, 235, 0.25);
}

.form-control::placeholder {
    color: var(--text-gray);
}

.form-label {
    color: var(--text-light);
    font-weight: 500;
}

/* Footer */
.footer {
    background: rgba(15, 23, 42, 0.95);
    padding: 40px 0 20px;
    margin-top: 80px;
    border-top: 1px solid rgba(37, 99, 235, 0.3);
    clear: both;
    position: relative;
    z-index: 1;
}

.footer h5 {
    color: var(--light-blue);
    margin-bottom: 20px;
}

.footer a {
    color: var(--text-gray);
    text-decoration: none;
    display: block;
    padding: 5px 0;
    transition: color 0.3s;
}

.footer a:hover {
    color: var(--light-blue);
}

/* Price Badge */
.price-badge {
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--light-blue);
}

/* Alert */
.alert {
    border-radius: 8px;
    border: none;
}

.alert-success {
    background: rgba(34, 197, 94, 0.2);
    color: #86efac;
    border: 1px solid rgba(34, 197, 94, 0.3);
}

.alert-danger {
    background: rgba(239, 68, 68, 0.2);
    color: #fca5a5;
    border: 1px solid rgba(239, 68, 68, 0.3);
}

.alert-info {
    background: rgba(37, 99, 235, 0.2);
    color: #93c5fd;
    border: 1px solid rgba(37, 99, 235, 0.3);
}

/* Video Player */
.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 10px;
    background: #000;
}

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

/* Dashboard */
.dashboard-card {
    background: rgba(30, 41, 59, 0.6);
    border: 1px solid rgba(37, 99, 235, 0.2);
    border-radius: 10px;
    padding: 20px;
    margin-bottom: 20px;
}

/* Responsive */
@media (max-width: 768px) {
    .hero-section h1 {
        font-size: 2rem;
    }
    
    .hero-section p {
        font-size: 1rem;
    }
}

/* Admin Styles */
.admin-sidebar {
    background: rgba(30, 41, 59, 0.9);
    min-height: calc(100vh - 70px);
    border-right: 1px solid rgba(37, 99, 235, 0.3);
}

.admin-sidebar .nav-link {
    color: var(--text-light);
    padding: 12px 20px;
    margin: 5px 0;
    border-radius: 5px;
}

.admin-sidebar .nav-link:hover,
.admin-sidebar .nav-link.active {
    background: var(--primary-blue);
    color: white !important;
}

.table {
    color: var(--text-light);
}

.table-dark {
    --bs-table-bg: rgba(30, 41, 59, 0.8);
    --bs-table-border-color: rgba(37, 99, 235, 0.2);
}

.table-hover tbody tr:hover {
    background: rgba(37, 99, 235, 0.1);
}

/* Course Description Styling */
.course-description {
    line-height: 1.8;
    font-size: 1.05rem;
}

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

.course-description ul.custom-list {
    list-style: none;
    padding-left: 0;
    margin-bottom: 1.5rem;
}

.course-description ul.custom-list li {
    padding: 10px 0;
    border-bottom: 1px solid rgba(37, 99, 235, 0.1);
    color: var(--text-light);
    font-size: 1rem;
}

.course-description ul.custom-list li:last-child {
    border-bottom: none;
}

.course-description ul.custom-list li i {
    font-size: 0.9rem;
}

/* Container Bottom Spacing - Prevents Footer Overlap */
body > .container,
.container.mt-5 {
    margin-bottom: 100px !important;
}

/* Course Details Page Responsive */
@media (max-width: 991px) {
    .sticky-top {
        position: relative !important;
        top: 0 !important;
    }
    
    .course-description {
        font-size: 1rem;
    }
    
    .course-description ul.custom-list li {
        padding: 8px 0;
        font-size: 0.95rem;
    }
}

@media (max-width: 576px) {
    .course-description {
        font-size: 0.95rem;
    }
    
    .course-description ul.custom-list li {
        padding: 6px 0;
        font-size: 0.9rem;
    }
    
    .container {
        padding-bottom: 80px;
    }
}