/* Reset and Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-purple: #6B46C1;
    --dark-purple: #553C9A;
    --light-purple: #8B5CF6;
    --lighter-purple: #A78BFA;
    --purple-bg: #F3E8FF;
    --text-dark: #1F2937;
    --text-light: #6B7280;
    --white: #FFFFFF;
    --shadow: rgba(107, 70, 193, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen', 'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
    background: linear-gradient(135deg, #F3E8FF 0%, #E9D5FF 100%);
    color: var(--text-dark);
    line-height: 1.6;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header Styles - Slim Design */
.header {
    background: linear-gradient(135deg, var(--primary-purple) 0%, var(--dark-purple) 100%);
    box-shadow: 0 2px 15px rgba(107, 70, 193, 0.2);
    position: sticky;
    top: 0;
    z-index: 1000;
    padding: 0.5rem 0;
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.header.scrolled {
    box-shadow: 0 4px 20px rgba(107, 70, 193, 0.3);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    flex-wrap: wrap;
    gap: 1rem;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 10px;
}

.logo {
    font-size: 2rem;
    background: var(--white);
    width: 45px;
    height: 45px;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    transition: var(--transition);
}

.logo:hover {
    transform: scale(1.05) rotate(5deg);
}

.site-title {
    color: var(--white);
    font-size: 1.5rem;
    font-weight: 700;
    text-shadow: 1px 1px 3px rgba(0, 0, 0, 0.2);
    letter-spacing: -0.5px;
}

.tags-nav {
    display: flex;
    gap: 8px;
    flex-wrap: wrap;
    align-items: center;
    max-width: 60%;
    overflow-x: auto;
    scrollbar-width: none;
    -ms-overflow-style: none;
}

.tags-nav::-webkit-scrollbar {
    display: none;
}

.tag {
    background: rgba(255, 255, 255, 0.2);
    color: var(--white);
    padding: 6px 14px;
    border-radius: 20px;
    text-decoration: none;
    font-size: 0.875rem;
    font-weight: 500;
    transition: var(--transition);
    border: 2px solid transparent;
    white-space: nowrap;
    backdrop-filter: blur(10px);
}

.tag:hover, .tag.active {
    background: var(--white);
    color: var(--primary-purple);
    transform: translateY(-2px);
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    cursor: pointer;
    padding: 6px;
    width: 30px;
    height: 30px;
    justify-content: center;
    align-items: center;
    border-radius: 6px;
    transition: var(--transition);
    position: relative;
}

.mobile-menu-toggle:hover {
    background: rgba(255, 255, 255, 0.1);
}

.mobile-menu-toggle span {
    width: 20px;
    height: 2.5px;
    background: var(--white);
    border-radius: 2px;
    transition: var(--transition);
    display: block;
}

.mobile-menu-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
}

.mobile-menu-toggle.active span:nth-child(2) {
    opacity: 0;
}

.mobile-menu-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -6px);
}

/* Main Content */
.main-content {
    padding: 2.5rem 0;
    min-height: calc(100vh - 200px);
    animation: fadeIn 0.6s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.section-title {
    color: var(--primary-purple);
    font-size: 2.25rem;
    margin-bottom: 2rem;
    text-align: center;
    font-weight: 800;
    letter-spacing: -1px;
}

/* Videos Grid */
.videos-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.video-card {
    background: var(--white);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 4px 15px var(--shadow);
    transition: var(--transition);
    cursor: pointer;
    position: relative;
}

.video-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(135deg, var(--primary-purple), var(--dark-purple));
    opacity: 0;
    transition: var(--transition);
    z-index: 1;
}

.video-card:hover {
    transform: translateY(-8px);
    box-shadow: 0 12px 30px rgba(107, 70, 193, 0.3);
}

.video-card:hover::before {
    opacity: 0.05;
}

.video-card a {
    text-decoration: none;
    color: inherit;
    display: block;
    position: relative;
    z-index: 2;
}

.video-thumbnail {
    position: relative;
    width: 100%;
    padding-top: 56.25%; /* 16:9 aspect ratio */
    background: linear-gradient(135deg, var(--lighter-purple), var(--light-purple));
    overflow: hidden;
    min-height: 200px;
}

.video-thumbnail img {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    transition: var(--transition);
}

.video-card:hover .video-thumbnail img {
    transform: scale(1.05);
}

.placeholder-thumbnail {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, var(--primary-purple), var(--dark-purple));
    padding: 2rem;
    text-align: center;
}

.thumbnail-icon {
    font-size: 5rem;
    margin-bottom: 1rem;
    opacity: 0.9;
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% {
        opacity: 0.9;
    }
    50% {
        opacity: 0.7;
    }
}

.thumbnail-text {
    color: var(--white);
    font-size: 1.1rem;
    font-weight: 600;
    line-height: 1.4;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.play-overlay {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    opacity: 0;
    transition: var(--transition);
    background: rgba(0, 0, 0, 0.7);
    border-radius: 50%;
    width: 80px;
    height: 80px;
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 10;
    backdrop-filter: blur(5px);
}

.video-card:hover .play-overlay {
    opacity: 1;
    transform: translate(-50%, -50%) scale(1.1);
}

.video-duration {
    position: absolute;
    bottom: 12px;
    right: 12px;
    background: rgba(0, 0, 0, 0.85);
    color: var(--white);
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 0.95rem;
    font-weight: 700;
    z-index: 5;
    backdrop-filter: blur(4px);
}

.video-info {
    padding: 1.25rem;
}

.video-title {
    font-size: 1.2rem;
    font-weight: 700;
    color: var(--text-dark);
    margin-bottom: 0.75rem;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
    line-height: 1.4;
    min-height: 3.2em;
    transition: var(--transition);
}

.video-card:hover .video-title {
    color: var(--primary-purple);
}

.video-meta {
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.85rem;
    color: var(--text-light);
    margin-bottom: 0.5rem;
}

.video-category {
    display: inline-block;
    background: var(--purple-bg);
    color: var(--primary-purple);
    padding: 4px 12px;
    border-radius: 12px;
    font-size: 0.75rem;
    font-weight: 600;
    margin-top: 0.5rem;
    transition: var(--transition);
}

.video-card:hover .video-category {
    background: var(--primary-purple);
    color: var(--white);
}

.no-videos {
    text-align: center;
    padding: 4rem 2rem;
    color: var(--text-light);
    font-size: 1.2rem;
    grid-column: 1 / -1;
}

/* Loading State */
.loading {
    display: inline-block;
    width: 20px;
    height: 20px;
    border: 3px solid rgba(107, 70, 193, 0.3);
    border-radius: 50%;
    border-top-color: var(--primary-purple);
    animation: spin 1s ease-in-out infinite;
}

@keyframes spin {
    to { transform: rotate(360deg); }
}

/* Footer */
.footer {
    background: linear-gradient(135deg, var(--primary-purple) 0%, var(--dark-purple) 100%);
    color: var(--white);
    padding: 3rem 0 1.5rem;
    margin-top: 4rem;
    position: relative;
}

.footer::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 1px;
    background: linear-gradient(90deg, transparent, rgba(255,255,255,0.3), transparent);
}

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

.footer-section h3 {
    margin-bottom: 1rem;
    font-size: 1.2rem;
}

.footer-section p,
.footer-section a {
    color: rgba(255, 255, 255, 0.8);
    text-decoration: none;
    display: block;
    margin-bottom: 0.5rem;
    transition: var(--transition);
}

.footer-section a:hover {
    color: var(--white);
    transform: translateX(5px);
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.9rem;
}

/* Scroll to Top Button */
.scroll-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: linear-gradient(135deg, var(--primary-purple), var(--dark-purple));
    color: var(--white);
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 1.5rem;
    box-shadow: 0 4px 15px rgba(107, 70, 193, 0.4);
    transition: var(--transition);
    z-index: 999;
}

.scroll-to-top:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 20px rgba(107, 70, 193, 0.6);
}

.scroll-to-top.show {
    display: flex;
}

/* Responsive Design */
@media (max-width: 768px) {
    .header {
        padding: 0.4rem 0;
    }

    .header-content {
        position: relative;
    }

    .logo-section {
        width: auto;
    }

    .logo {
        width: 40px;
        height: 40px;
        font-size: 1.75rem;
    }

    .site-title {
        font-size: 1.3rem;
    }

    .tags-nav {
        position: absolute;
        top: 100%;
        left: 0;
        right: 0;
        background: var(--primary-purple);
        flex-direction: column;
        align-items: stretch;
        padding: 1rem;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.3s ease;
        box-shadow: 0 4px 15px rgba(0, 0, 0, 0.2);
        max-width: 100%;
        z-index: 999;
    }

    .tags-nav.active {
        max-height: 500px;
        margin-top: 0.5rem;
    }

    .tags-nav .tag {
        width: 100%;
        text-align: center;
        padding: 10px;
    }

    .mobile-menu-toggle {
        display: flex;
        position: absolute;
        top: 50%;
        right: 20px;
        transform: translateY(-50%);
    }

    .videos-grid {
        grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
        gap: 1.5rem;
    }

    .section-title {
        font-size: 1.75rem;
    }

    .main-content {
        padding: 2rem 0;
    }

    .video-title {
        font-size: 1.1rem;
        min-height: 2.8em;
    }

    .thumbnail-icon {
        font-size: 4rem;
    }

    .thumbnail-text {
        font-size: 1rem;
    }

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .scroll-to-top {
        width: 45px;
        height: 45px;
        bottom: 20px;
        right: 20px;
    }
}

@media (max-width: 480px) {
    .videos-grid {
        grid-template-columns: 1fr;
        gap: 1rem;
    }

    .container {
        padding: 0 15px;
    }

    .video-thumbnail {
        min-height: 180px;
    }

    .thumbnail-icon {
        font-size: 3.5rem;
    }

    .thumbnail-text {
        font-size: 0.9rem;
    }

    .section-title {
        font-size: 1.5rem;
    }
}

/* Print Styles */
@media print {
    .header, .footer, .mobile-menu-toggle {
        display: none;
    }
}