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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, Cantarell, sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #fff;
}

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

/* Header */
.navbar {
    background: #fff;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 20px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo {
    width: 40px;
    height: 40px;
}

.brand-text {
    font-size: 1.5rem;
    font-weight: bold;
    color: #2c5aa0;
}

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

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: #2c5aa0;
}

/* Main Content */
main {
    margin-top: 80px;
}

/* Hero Section */
.hero {
    position: relative;
    height: 60vh;
    display: flex;
    align-items: center;
    color: white;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, #2c5aa0 0%, #1e3a5f 100%);
    z-index: -1;
}

.hero-content {
    text-align: center;
    max-width: 600px;
    margin: 0 auto;
}

.hero h1 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero p {
    font-size: 1.25rem;
    margin-bottom: 2rem;
    opacity: 0.9;
}

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 5px;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: #ff6b35;
    color: white;
}

.btn-primary:hover {
    background: #e55a2b;
    transform: translateY(-2px);
}

.btn-secondary {
    background: transparent;
    color: #2c5aa0;
    border: 2px solid #2c5aa0;
}

.btn-secondary:hover {
    background: #2c5aa0;
    color: white;
}

/* Sections */
section {
    padding: 4rem 0;
}

section h2 {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: #333;
}

/* Video Grid */
.video-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.video-card {
    background: white;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    overflow: hidden;
    transition: transform 0.3s, box-shadow 0.3s;
}

.video-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 10px 25px rgba(0,0,0,0.15);
}

.video-thumbnail {
    width: 100%;
    height: 200px;
    object-fit: cover;
}

.video-info {
    padding: 1.5rem;
}

.video-title {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: 0.5rem;
    color: #333;
}

.video-channel {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: 0.5rem;
}

.video-meta {
    display: flex;
    justify-content: space-between;
    font-size: 0.85rem;
    color: #888;
    margin-bottom: 1rem;
}

.video-description {
    color: #666;
    font-size: 0.9rem;
    line-height: 1.4;
    margin-bottom: 1rem;
}

.video-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
}

.tag {
    background: #f0f0f0;
    padding: 0.25rem 0.5rem;
    border-radius: 15px;
    font-size: 0.8rem;
    color: #666;
}

/* Category Grid */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
}

.category-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    text-align: center;
    transition: transform 0.3s;
}

.category-card:hover {
    transform: translateY(-5px);
}

.category-card h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
    color: #2c5aa0;
}

.category-card p {
    color: #666;
    margin-bottom: 1.5rem;
}

.category-card a {
    color: #ff6b35;
    text-decoration: none;
    font-weight: 600;
}

/* Search and Filters */
.search-filters {
    background: #f8f9fa;
    padding: 2rem 0;
    margin-bottom: 2rem;
}

.search-bar {
    display: flex;
    gap: 1rem;
    margin-bottom: 1rem;
    flex-wrap: wrap;
}

.search-input {
    flex: 1;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

.filter-group {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
}

.filter-select {
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 0.9rem;
}

/* Video Detail Page */
.video-detail {
    max-width: 1000px;
    margin: 0 auto;
    padding: 2rem 20px;
}

.video-embed {
    width: 100%;
    height: 500px;
    border: none;
    border-radius: 10px;
    margin-bottom: 2rem;
}

.video-detail-info h1 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: #333;
}

.video-detail-meta {
    display: flex;
    gap: 2rem;
    margin-bottom: 1.5rem;
    flex-wrap: wrap;
}

.video-detail-meta span {
    color: #666;
    font-size: 0.9rem;
}

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

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 600;
    color: #333;
}

.form-group input,
.form-group textarea,
.form-group select {
    width: 100%;
    padding: 12px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 1rem;
}

.form-group textarea {
    height: 120px;
    resize: vertical;
}

/* Footer */
footer {
    background: #333;
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-section h4 {
    margin-bottom: 1rem;
    color: #ff6b35;
}

.footer-section ul {
    list-style: none;
}

.footer-section ul li {
    margin-bottom: 0.5rem;
}

.footer-section a {
    color: #ccc;
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section a:hover {
    color: #ff6b35;
}

.footer-bottom {
    border-top: 1px solid #555;
    padding-top: 1rem;
    text-align: center;
    color: #ccc;
}

/* Utility Classes */
.text-center {
    text-align: center;
}

.mb-2 {
    margin-bottom: 2rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .navbar .container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav-menu {
        gap: 1rem;
    }

    .hero h1 {
        font-size: 2rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .video-grid {
        grid-template-columns: 1fr;
    }

    .category-grid {
        grid-template-columns: 1fr;
    }

    .search-bar {
        flex-direction: column;
    }

    .filter-group {
        justify-content: center;
    }

    .video-embed {
        height: 300px;
    }

    .video-detail-meta {
        flex-direction: column;
        gap: 0.5rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }

    section {
        padding: 2rem 0;
    }

    section h2 {
        font-size: 2rem;
    }

    .hero {
        height: 50vh;
    }

    .video-info {
        padding: 1rem;
    }
}