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

:root {
    --primary-color: #0f3460;
    --secondary-color: #16213e;
    --accent-color: #00d4ff;
    --accent-glow: #00d4ff;
    --text-primary: #e9ecef;
    --text-secondary: #adb5bd;
    --card-bg: rgba(22, 33, 62, 0.4);
    --card-border: rgba(0, 212, 255, 0.1);
    --button-shadow: 0 8px 32px rgba(0, 212, 255, 0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Poppins', sans-serif;
    background: linear-gradient(135deg, #0f3460 0%, #16213e 50%, #0f1f38 100%);
    background-attachment: fixed;
    color: var(--text-primary);
    overflow-x: hidden;
    position: relative;
}

/* Subtle background pattern */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background-image: 
        radial-gradient(circle at 20% 50%, rgba(0, 212, 255, 0.03) 0%, transparent 50%),
        radial-gradient(circle at 80% 80%, rgba(0, 212, 255, 0.03) 0%, transparent 50%);
    pointer-events: none;
    z-index: -1;
}

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

/* Navigation Bar */
.navbar {
    position: sticky;
    top: 0;
    z-index: 1000;
    background: rgba(15, 52, 96, 0.8);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--card-border);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 1rem 20px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: clamp(1rem, 3vw, 1.5rem);
    font-weight: 700;
    color: var(--accent-color);
    text-decoration: none;
    white-space: nowrap;
}

.logo-icon {
    font-size: 2rem;
    animation: bobbing 2s infinite ease-in-out;
}

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

.nav-link {
    color: var(--text-primary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

.nav-link::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: linear-gradient(90deg, var(--accent-color), transparent);
    transition: width 0.3s ease;
}

.nav-link:hover {
    color: var(--accent-color);
}

.nav-link:hover::after {
    width: 100%;
}

.hamburger {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 6px;
}

.hamburger span {
    width: 25px;
    height: 3px;
    background: var(--accent-color);
    border-radius: 2px;
    transition: var(--transition);
}

/* Home Section */
.home {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    overflow: hidden;
    padding: 2rem 0;
}

.home-content {
    text-align: center;
    z-index: 2;
    animation: slideUp 0.8s ease-out;
}

.hero-icons {
    display: flex;
    justify-content: center;
    gap: 2rem;
    margin-bottom: 2rem;
    flex-wrap: wrap;
}

.icon {
    font-size: 4rem;
    opacity: 0.8;
}

.animate-icon {
    animation: float 3s ease-in-out infinite;
}

.hero-title {
    font-family: 'Montserrat', sans-serif;
    font-size: clamp(2.5rem, 8vw, 4rem);
    margin-bottom: 1rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--accent-color), #00a8cc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    letter-spacing: -1px;
}

.hero-subtitle {
    font-size: clamp(1rem, 3vw, 1.5rem);
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.btn {
    padding: 0.75rem 1.5rem;
    border: none;
    border-radius: 50px;
    font-family: 'Poppins', sans-serif;
    font-weight: 600;
    cursor: pointer;
    text-decoration: none;
    display: inline-block;
    transition: var(--transition);
    font-size: 1rem;
    text-transform: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent-color), #00a8cc);
    color: #0f3460;
    box-shadow: 0 8px 32px rgba(0, 212, 255, 0.3);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 48px rgba(0, 212, 255, 0.5);
}

.btn-secondary {
    background: rgba(0, 212, 255, 0.1);
    color: var(--accent-color);
    border: 2px solid var(--accent-color);
}

.btn-secondary:hover {
    background: var(--accent-color);
    color: #0f3460;
    box-shadow: var(--button-shadow);
    transform: translateY(-2px);
}

.btn-accent {
    background: rgba(0, 212, 255, 0.15);
    color: var(--accent-color);
    border: 1px solid var(--accent-color);
}

.btn-accent:hover {
    background: var(--accent-color);
    color: #0f3460;
    transform: translateY(-2px);
}

.btn-outline {
    background: transparent;
    color: var(--accent-color);
    border: 2px solid var(--accent-color);
}

.btn-outline:hover {
    background: var(--accent-color);
    color: #0f3460;
    transform: translateY(-2px);
}

.btn-large {
    padding: 1rem 3rem;
    font-size: 1.1rem;
}

.btn-small {
    padding: 0.5rem 1rem;
    font-size: 0.9rem;
}

/* Section Styles */
section {
    padding: 5rem 0;
}

.section-title {
    font-family: 'Montserrat', sans-serif;
    font-size: clamp(2rem, 5vw, 3rem);
    text-align: center;
    margin-bottom: 0.5rem;
    background: linear-gradient(135deg, var(--accent-color), #00a8cc);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    font-weight: 700;
}

.section-subtitle {
    text-align: center;
    color: var(--text-secondary);
    font-size: 1.1rem;
    margin-bottom: 3rem;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* Tests Section */
.tests {
    background: linear-gradient(135deg, rgba(15, 52, 96, 0.5), rgba(22, 33, 62, 0.5));
}

.tests-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.test-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2rem;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease-out;
}

.test-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 212, 255, 0.3);
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
}

.card-header {
    text-align: center;
    margin-bottom: 1.5rem;
}

.university-logo {
    font-size: 3rem;
    margin-bottom: 1rem;
    display: inline-block;
}

.card-header h3 {
    font-size: 1.5rem;
    margin-bottom: 0.5rem;
}

.test-code {
    color: var(--accent-color);
    font-weight: 600;
    font-size: 0.9rem;
}

.card-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    line-height: 1.6;
}

.card-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1rem;
}

/* Materials Section */
.materials {
    background: linear-gradient(135deg, rgba(22, 33, 62, 0.5), rgba(15, 52, 96, 0.5));
}

.materials-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 2rem;
}

.material-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2rem;
    text-align: center;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease-out;
}

.material-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 212, 255, 0.3);
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
}

.material-header {
    margin-bottom: 1rem;
}

.material-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: 1rem;
}

.material-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.5rem;
}

.material-description {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

.material-buttons {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.75rem;
}

/* WhatsApp Community Section */
.whatsapp-section {
    background: linear-gradient(135deg, rgba(37, 211, 102, 0.15), rgba(0, 212, 255, 0.08));
    position: relative;
    overflow: hidden;
}

.whatsapp-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: radial-gradient(circle at 20% 50%, rgba(37, 211, 102, 0.1) 0%, transparent 50%),
                radial-gradient(circle at 80% 80%, rgba(0, 212, 255, 0.05) 0%, transparent 50%);
    pointer-events: none;
}

.whatsapp-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 2rem 0;
    position: relative;
    z-index: 1;
}

.whatsapp-card {
    background: linear-gradient(135deg, rgba(37, 211, 102, 0.2), rgba(22, 33, 62, 0.5));
    backdrop-filter: blur(10px);
    border: 2px solid rgba(37, 211, 102, 0.3);
    border-radius: 20px;
    padding: 3rem;
    text-align: center;
    max-width: 600px;
    width: 100%;
    animation: slideUp 0.8s ease-out;
    transition: var(--transition);
    box-shadow: 0 20px 60px rgba(37, 211, 102, 0.1);
}

.whatsapp-card:hover {
    transform: translateY(-10px);
    border-color: rgba(37, 211, 102, 0.5);
    box-shadow: 0 30px 80px rgba(37, 211, 102, 0.2);
}

.whatsapp-header {
    margin-bottom: 1.5rem;
}

.whatsapp-icon {
    font-size: 3.5rem;
    display: block;
    margin-bottom: 1rem;
    animation: float 3s ease-in-out infinite;
}

.whatsapp-card h2 {
    font-size: 2rem;
    color: #25d366;
    margin-bottom: 0.5rem;
    font-weight: 700;
}

.whatsapp-description {
    color: var(--text-secondary);
    font-size: 1.05rem;
    line-height: 1.7;
    margin-bottom: 1.5rem;
}

.whatsapp-features {
    background: rgba(37, 211, 102, 0.1);
    border-left: 4px solid #25d366;
    padding: 1.5rem;
    border-radius: 8px;
    margin-bottom: 2rem;
    color: var(--text-secondary);
    text-align: left;
    display: inline-block;
    line-height: 2;
    font-size: 0.95rem;
}

.whatsapp-features strong {
    color: #25d366;
    margin-right: 0.5rem;
}

/* Resources Section */
.resources {
    background: linear-gradient(135deg, rgba(15, 52, 96, 0.5), rgba(22, 33, 62, 0.5));
}

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

.resource-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2.5rem 2rem;
    text-align: center;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease-out;
}

.resource-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 212, 255, 0.3);
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
}

.resource-icon {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    display: block;
}

.resource-card h3 {
    font-size: 1.3rem;
    margin-bottom: 0.75rem;
}

.resource-card p {
    color: var(--text-secondary);
    margin-bottom: 1.5rem;
    font-size: 0.95rem;
}

/* About Section */
.about {
    background: linear-gradient(135deg, rgba(22, 33, 62, 0.5), rgba(15, 52, 96, 0.5));
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 4rem;
    align-items: center;
    margin-top: 3rem;
}

.about-image {
    text-align: center;
    position: relative;
}

.creator-photo {
    width: 250px;
    height: 250px;
    object-fit: cover;
    border-radius: 16px;
    border: 2px solid var(--accent-color);
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
    animation: float 3s ease-in-out infinite;
    display: block;
    margin: 0 auto;
}

.profile-placeholder {
    width: 250px;
    height: 250px;
    margin: 0 auto;
    background: linear-gradient(135deg, rgba(0, 212, 255, 0.2), rgba(0, 212, 255, 0.1));
    border: 2px solid var(--accent-color);
    border-radius: 16px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 5rem;
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
    animation: float 3s ease-in-out infinite;
}

.about-text h3 {
    font-size: 2rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.about-text h4 {
    font-size: 1.2rem;
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
    color: #00a8cc;
}

.about-text p {
    color: var(--text-secondary);
    line-height: 1.8;
    margin-bottom: 1.5rem;
    font-size: 1rem;
}

.social-links {
    display: flex;
    gap: 1.5rem;
    flex-wrap: wrap;
    margin-top: 2rem;
}

.social-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    padding: 0.75rem 1.5rem;
    background: rgba(0, 212, 255, 0.1);
    border: 2px solid var(--accent-color);
    border-radius: 50px;
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
    font-weight: 500;
}

.social-link:hover {
    background: var(--accent-color);
    color: #0f3460;
    transform: translateY(-3px);
}

/* Footer */
.footer {
    background: rgba(15, 52, 96, 0.9);
    border-top: 1px solid var(--card-border);
    padding: 2rem 0;
    text-align: center;
    color: var(--text-secondary);
    margin-top: 2rem;
}

.footer a {
    color: var(--accent-color);
    text-decoration: none;
    transition: var(--transition);
}

.footer a:hover {
    color: #00a8cc;
    text-decoration: underline;
}

/* Animations */
@keyframes float {
    0%, 100% {
        transform: translateY(0px);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes bobbing {
    0%, 100% {
        transform: translateY(0px) rotate(0deg);
    }
    50% {
        transform: translateY(-10px) rotate(5deg);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(40px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.9);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

/* Maths Tricks Section */
.maths-tricks {
    background: linear-gradient(135deg, rgba(15, 52, 96, 0.5), rgba(22, 33, 62, 0.5));
}

.single-tricks-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 2rem;
}

.single-tricks-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2.5rem;
    text-align: center;
    max-width: 800px;
    width: 100%;
    animation: fadeInUp 0.6s ease-out;
    transition: var(--transition);
}

.single-tricks-card:hover {
    transform: translateY(-8px);
    border-color: rgba(0, 212, 255, 0.3);
    box-shadow: 0 20px 50px rgba(0, 212, 255, 0.15);
}

.tricks-content {
    margin-bottom: 2rem;
}

.tricks-main-icon {
    font-size: 3rem;
    display: block;
    margin-bottom: 1rem;
}

.single-tricks-card h3 {
    font-size: 1.8rem;
    margin-bottom: 0.75rem;
    color: var(--accent-color);
}

.tricks-main-description {
    color: var(--text-secondary);
    font-size: 1rem;
    line-height: 1.6;
}

.tricks-links {
    display: flex;
    gap: 1rem;
    flex-wrap: wrap;
    justify-content: center;
}

/* Calculator Section */
.calculator {
    background: linear-gradient(135deg, rgba(22, 33, 62, 0.5), rgba(15, 52, 96, 0.5));
}

.calculator-wrapper {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-top: 2rem;
}

.calculator-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 2px solid var(--accent-color);
    border-radius: 16px;
    padding: 3rem 2rem;
    text-align: center;
    max-width: 500px;
    animation: scaleIn 0.6s ease-out;
}

.calculator-card h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
    color: var(--accent-color);
}

.calculator-description {
    color: var(--text-secondary);
    margin-bottom: 2rem;
    font-size: 1rem;
    line-height: 1.6;
}

.calculator-buttons {
    display: flex;
    gap: 1rem;
    justify-content: center;
}

/* YouTube Channels Section */
.youtube-channels {
    background: linear-gradient(135deg, rgba(15, 52, 96, 0.5), rgba(22, 33, 62, 0.5));
}

.youtube-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.youtube-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 2rem;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease-out;
}

.youtube-card:hover {
    transform: translateY(-8px);
    border-color: rgba(255, 0, 0, 0.3);
    box-shadow: 0 20px 50px rgba(255, 0, 0, 0.1);
}

.youtube-header {
    text-align: center;
    margin-bottom: 1.5rem;
}

.youtube-icon {
    font-size: 2.5rem;
    display: inline-block;
    margin-bottom: 1rem;
}

.youtube-card h3 {
    font-size: 1.5rem;
    color: #ff0000;
    margin-bottom: 0.5rem;
}

.youtube-description {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    font-size: 0.95rem;
    line-height: 1.6;
}

.youtube-topics {
    color: var(--accent-color);
    font-size: 0.9rem;
    margin-bottom: 1.5rem;
    font-weight: 500;
}

/* University Links Section */
.university-links {
    background: linear-gradient(135deg, rgba(22, 33, 62, 0.5), rgba(15, 52, 96, 0.5));
}

.links-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 1.5rem;
}

.link-card {
    background: var(--card-bg);
    backdrop-filter: blur(10px);
    border: 1px solid var(--card-border);
    border-radius: 16px;
    padding: 1.5rem;
    text-align: center;
    transition: var(--transition);
    animation: fadeInUp 0.6s ease-out;
}

.link-card:hover {
    transform: translateY(-6px);
    border-color: rgba(0, 212, 255, 0.3);
    box-shadow: 0 15px 40px rgba(0, 212, 255, 0.1);
    background: rgba(22, 33, 62, 0.6);
}

.link-header {
    margin-bottom: 1rem;
}

.link-icon {
    font-size: 2.5rem;
    display: block;
    margin-bottom: 0.5rem;
}

.link-card h3 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
    color: var(--accent-color);
}

.link-card p {
    color: var(--text-secondary);
    font-size: 0.85rem;
    line-height: 1.5;
    margin-bottom: 1rem;
}

/* Scroll Reveal Animation */
.scroll-reveal {
    opacity: 0;
    transform: translateY(30px);
}

.scroll-reveal.revealed {
    animation: fadeInUp 0.6s ease-out forwards;
}

/* Responsive Design - Ultra Small Phones (320px and below) */
@media (max-width: 360px) {
    html {
        font-size: 14px;
    }

    .container {
        padding: 0 15px;
    }

    .nav-container {
        padding: 0.75rem 15px;
    }

    .logo-text {
        font-size: 1.1rem;
    }

    .hero-title {
        font-size: 1.75rem;
        line-height: 1.3;
    }

    .hero-subtitle {
        font-size: 0.9rem;
        line-height: 1.4;
    }

    .btn-large {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }

    .btn-small {
        padding: 0.5rem 0.75rem;
        font-size: 0.8rem;
    }

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

    .section-subtitle {
        font-size: 0.9rem;
    }

    .hero-icons {
        gap: 0.5rem;
    }

    .icon {
        font-size: 2rem;
    }

    .university-logo,
    .material-icon,
    .tricks-icon,
    .resource-icon,
    .youtube-icon,
    .link-icon {
        font-size: 2rem;
    }

    .test-card,
    .material-card,
    .resource-card,
    .tricks-card,
    .youtube-card,
    .link-card,
    .calculator-card {
        padding: 1rem;
    }

    .card-buttons,
    .material-buttons {
        grid-template-columns: 1fr;
        gap: 0.5rem;
    }

    .tricks-links {
        gap: 0.5rem;
    }

    .single-tricks-card {
        padding: 1.5rem;
    }

    .single-tricks-card h3 {
        font-size: 1.3rem;
    }

    .tricks-main-icon {
        font-size: 2rem;
    }

    .whatsapp-card {
        padding: 1.5rem;
    }

    .whatsapp-card h2 {
        font-size: 1.5rem;
    }

    .whatsapp-description {
        font-size: 0.95rem;
    }

    .whatsapp-icon {
        font-size: 2.5rem;
    }

    .whatsapp-features {
        padding: 1rem;
        font-size: 0.9rem;
        line-height: 1.7;
    }

    .about-image {
        margin-bottom: 1rem;
    }

    .profile-placeholder {
        width: 150px;
        height: 150px;
        font-size: 3rem;
    }

    .about-text h3 {
        font-size: 1.3rem;
    }

    .about-text h4 {
        font-size: 0.95rem;
    }

    .about-text p {
        font-size: 0.9rem;
    }

    .social-links {
        flex-direction: column;
        gap: 0.75rem;
    }

    .social-link {
        width: 100%;
        padding: 0.6rem 1rem;
        font-size: 0.85rem;
    }

    .footer {
        padding: 1.5rem 0;
        font-size: 0.85rem;
    }
}

/* Responsive Design - Small Phones (361px to 480px) */
@media (min-width: 361px) and (max-width: 480px) {
    .container {
        padding: 0 18px;
    }

    .btn-large {
        padding: 0.875rem 2rem;
        font-size: 1rem;
    }

    .btn-small {
        padding: 0.5rem 0.9rem;
        font-size: 0.85rem;
    }

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

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

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

    .hero-icons {
        gap: 0.75rem;
    }

    .icon {
        font-size: 2.5rem;
    }

    .test-card,
    .material-card,
    .resource-card,
    .tricks-card,
    .youtube-card,
    .link-card {
        padding: 1.25rem;
    }

    .card-buttons,
    .material-buttons {
        grid-template-columns: 1fr;
    }

    .about-text h3 {
        font-size: 1.5rem;
    }

    .about-text h4 {
        font-size: 1rem;
    }

    .about-text p {
        font-size: 0.95rem;
    }

    .social-links {
        flex-direction: column;
    }

    .social-link {
        width: 100%;
        justify-content: center;
        padding: 0.7rem 1.2rem;
    }

    .profile-placeholder {
        width: 180px;
        height: 180px;
        font-size: 3.5rem;
    }

    section {
        padding: 2.5rem 0;
    }
}

/* Responsive Design - Tablets and Medium Devices (481px to 768px) */
@media (min-width: 481px) and (max-width: 768px) {
    .container {
        padding: 0 20px;
    }

    .hamburger {
        display: flex;
    }

    .nav-menu {
        position: fixed;
        left: -100%;
        top: 70px;
        flex-direction: column;
        background: rgba(15, 52, 96, 0.95);
        width: 100%;
        text-align: center;
        transition: 0.3s;
        gap: 0;
        padding: 1rem 0;
        max-height: calc(100vh - 70px);
        overflow-y: auto;
    }

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

    .nav-link {
        display: block;
        padding: 0.85rem 0;
        font-size: 0.95rem;
    }

    .nav-link::after {
        display: none;
    }

    .nav-link:hover {
        background: rgba(0, 212, 255, 0.1);
    }

    section {
        padding: 3rem 0;
    }

    .hero-title {
        font-size: 2.5rem;
    }

    .hero-subtitle {
        font-size: 1.2rem;
    }

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

    .tests-grid,
    .materials-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .youtube-grid,
    .links-grid,
    .resources-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }

    .about-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }

    .profile-placeholder {
        width: 220px;
        height: 220px;
        font-size: 4.5rem;
    }

    .card-buttons,
    .material-buttons,
    .tricks-buttons {
        grid-template-columns: 1fr 1fr;
        gap: 0.8rem;
    }

    .social-links {
        justify-content: center;
        gap: 1rem;
    }

    .social-link {
        padding: 0.75rem 1.25rem;
        font-size: 0.95rem;
    }

    .hero-icons {
        gap: 1rem;
    }

    .icon {
        font-size: 2.5rem;
    }

    .btn-small {
        padding: 0.55rem 1rem;
        font-size: 0.9rem;
    }

    .test-card,
    .material-card,
    .resource-card,
    .tricks-card,
    .youtube-card,
    .link-card {
        padding: 1.75rem;
    }
}

/* Responsive Design - Large Tablets (769px to 1024px) */
@media (min-width: 769px) and (max-width: 1024px) {
    .container {
        padding: 0 25px;
    }

    .section-title {
        font-size: 2.5rem;
    }

    .tests-grid,
    .materials-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }

    .youtube-grid,
    .links-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 2rem;
    }

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

    .about-content {
        grid-template-columns: 1fr 1fr;
        gap: 3rem;
    }

    .profile-placeholder {
        width: 230px;
        height: 230px;
    }

    .hero-title {
        font-size: 3rem;
    }

    .hero-subtitle {
        font-size: 1.3rem;
    }

    section {
        padding: 4rem 0;
    }
}

/* Responsive Design - Desktop (1025px and above) */
@media (min-width: 1025px) {
    .container {
        padding: 0 20px;
        max-width: 1200px;
    }

    .tests-grid,
    .materials-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }

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

    .links-grid {
        grid-template-columns: repeat(3, 1fr);
        gap: 2rem;
    }

    .resources-grid {
        grid-template-columns: repeat(4, 1fr);
        gap: 2rem;
    }

    .about-content {
        grid-template-columns: 1fr 1fr;
        gap: 4rem;
    }

    section {
        padding: 5rem 0;
    }
}

/* Landscape Mode Optimization */
@media (max-height: 600px) and (orientation: landscape) {
    .home {
        min-height: auto;
        padding: 2rem 0;
    }

    .hero-title {
        font-size: clamp(1.5rem, 4vw, 2.5rem);
    }

    .hero-icons {
        gap: 0.5rem;
    }

    .icon {
        font-size: clamp(1.5rem, 3vw, 2rem);
    }

    .btn-large {
        padding: 0.75rem 1.5rem;
        font-size: 0.9rem;
    }

    section {
        padding: 2rem 0;
    }
}

/* High DPI / Retina Displays */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    body {
        -webkit-font-smoothing: antialiased;
        -moz-osx-font-smoothing: grayscale;
    }
}

/* Touch Device Optimization */
@media (hover: none) and (pointer: coarse) {
    .btn {
        min-height: 44px;
        min-width: 44px;
        padding: 0.75rem 1.5rem;
    }

    .btn-small {
        min-height: 40px;
        padding: 0.65rem 1rem;
    }

    .nav-link {
        padding: 0.75rem 1rem;
    }

    .test-card,
    .material-card,
    .resource-card,
    .tricks-card,
    .youtube-card,
    .link-card {
        transition: all 0.2s ease;
    }

    .test-card:active,
    .material-card:active,
    .resource-card:active,
    .tricks-card:active,
    .youtube-card:active,
    .link-card:active {
        transform: translateY(-4px);
    }
}

/* Loading Spinner Animation (for future use) */
@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

.loading {
    animation: spin 1s linear infinite;
}