/* Responsive Design */
@media (max-width: 1024px) {
    .about-layout {
        grid-template-columns: 280px 1fr;
        gap: var(--spacing-lg);
    }

    .profile-image {
        height: 280px;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .hero-slideshow {
        height: calc(100vh - 150px);
        min-height: 490px;
    }

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

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

    .section-header h2 {
        font-size: 1.625rem;
    }

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

    .service-card {
        padding: var(--spacing-md);
    }

    .service-card h3 {
        font-size: 1.25rem;
    }

    .service-icon {
        width: 60px;
        height: 60px;
    }

    .navbar .container {
        flex-wrap: wrap;
    }

    .nav-brand {
        flex: 0 0 auto;
    }

    .logo {
        height: 50px;
    }

    /* Mobile Navigation */
    .hamburger {
        display: flex;
        order: 2;
    }

    .language-selector {
        order: 3;
    }

    .nav-links {
        position: fixed;
        top: 0;
        left: -100%;
        width: 80%;
        max-width: 300px;
        height: 100vh;
        background-color: var(--white);
        flex-direction: column;
        align-items: flex-start;
        padding: 5rem 2rem 2rem;
        margin: 0;
        box-shadow: 2px 0 10px rgba(0, 0, 0, 0.1);
        transition: left 0.3s ease;
        z-index: 1000;
        overflow-y: auto;
    }

    .nav-links.active {
        left: 0;
    }

    .nav-link {
        width: 100%;
        padding: 1rem 0;
        border-radius: 0;
        border-bottom: 1px solid var(--border-color);
    }

    body.menu-open {
        overflow: hidden;
    }

    body.menu-open::before {
        content: '';
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100%;
        background-color: rgba(0, 0, 0, 0.5);
        z-index: 999;
    }

    section {
        padding: var(--spacing-lg) 0;
    }

    .stats-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .stat-number {
        font-size: 2.5rem;
    }

    .about-layout {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }

    .about-sidebar {
        position: relative;
        top: 0;
    }

    .profile-card {
        max-width: 400px;
        margin: 0 auto;
    }

    .contact-layout {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }

    .course-hero-title {
        font-size: 1.75rem;
    }

    .course-hero-subtitle {
        font-size: 1rem;
    }

    .flashcard {
        height: 250px;
    }

    .card-text {
        font-size: 1.25rem;
    }

    .card-lang {
        font-size: 0.75rem;
    }

    .flashcard-controls {
        flex-direction: column;
    }

    .control-btn {
        width: 100%;
    }

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

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

    .course-item {
        flex-direction: column;
        align-items: flex-start;
    }

    .course-item .primary-btn {
        width: 100%;
        text-align: center;
    }
}

@media (max-width: 480px) {
    .hero-slideshow {
        height: calc(100vh - 160px);
        min-height: 440px;
    }

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

    .container {
        padding: 0 var(--spacing-sm);
    }

    .service-card {
        padding: var(--spacing-sm);
    }

    .slideshow-dots {
        bottom: 15px;
    }

    .dot {
        height: 10px;
        width: 10px;
    }

    .flashcard {
        height: 220px;
    }

    .card-lang {
        font-size: 0.75rem;
    }

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

    .confidence-controls {
        flex-direction: column;
    }

    .confidence-btn {
        max-width: 100%;
    }
}

/* Smooth Transitions */
section,
.service-card,
.lang-btn {
    transition: all 0.3s ease;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.reveal {
    opacity: 0;
    transform: translateY(30px);
    transition: all 0.8s cubic-bezier(0.5, 0, 0, 1);
}

.reveal.active {
    opacity: 1;
    transform: translateY(0);
}

.delay-100 {
    transition-delay: 0.1s;
}

.delay-200 {
    transition-delay: 0.2s;
}

.delay-300 {
    transition-delay: 0.3s;
}