.main-nav {
    display: flex;
    justify-content: center;
    gap: 30px;
    margin: 20px 0;
    flex-wrap: wrap;
}

.main-nav a {
    font-size: 1.2em;
    text-decoration: none;
    color: #1a237e;
    font-weight: bold;
    position: relative;
    padding: 5px 10px;
}

.main-nav a::after {
    content: '';
    position: absolute;
    left: 0;
    bottom: -2px;
    width: 100%;
    height: 2px;
    background: #1a237e;
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.main-nav a:hover::after,
.main-nav a.active::after {
    transform: scaleX(1);
}
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Comic Sans MS', cursive, sans-serif;
}

body {
    background-color: #f0f8ff;
    min-height: 100vh;
}

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

header {
    text-align: center;
    padding: 20px;
    background-color: #4CAF50;
    color: white;
    border-radius: 15px;
    margin-bottom: 30px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    position: relative;
    width: 100%;
}

header h1 {
    font-size: 2.5em;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.2);
}

.slogan {
    font-size: 1.2em;
    font-style: italic;
    margin: 0;
    padding: 10px;
    color: #fff;
    text-shadow: 1px 1px 2px rgba(0,0,0,0.2);
    animation: fadeIn 2s ease-in;
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(-10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.activities {
    display: flex;
    justify-content: center;
    gap: 20px;
    flex-wrap: wrap;
    margin: 30px 0;
}

.activity-btn {
    padding: 15px 30px;
    font-size: 1.2em;
    background-color: #FF9800;
    color: white;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.2s, background-color 0.2s;
}

.activity-btn:hover {
    transform: scale(1.05);
    background-color: #F57C00;
}

.activity-content {
    background-color: white;
    padding: 15px;
    border-radius: 15px;
    min-height: auto;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    margin: 20px 0;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
}

.activity-content:empty {
    display: none;
}

.progress-section {
    text-align: center;
    margin-top: 20px;
}

.progress-bar {
    width: 100%;
    height: 20px;
    background-color: #e0e0e0;
    border-radius: 10px;
    margin-top: 10px;
}

.progress {
    height: 100%;
    background-color: #4CAF50;
    border-radius: 10px;
    width: 0%;
    transition: width 0.3s;
}

footer {
    background-color: #f8f8f8;
    padding: 40px 0;
    margin-top: 50px;
    border-top: 1px solid #e0e0e0;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-around;
    flex-wrap: wrap;
    gap: 30px;
    padding: 0 20px;
}

.footer-section {
    min-width: 200px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.footer-section h4 {
    color: #333;
    margin-bottom: 15px;
    font-size: 1.2em;
}

.footer-section a {
    color: #666;
    text-decoration: none;
    transition: color 0.3s;
    font-size: 1em;
    padding: 5px 0;
}

.footer-section a:hover {
    color: #4CAF50;
}

.footer-section p {
    color: #666;
    font-size: 0.9em;
}

@media (max-width: 768px) {
    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
    }

    .footer-section {
        width: 100%;
        align-items: center;
    }
}

/* Nature cards styles */
.nature-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    padding: 20px;
    margin-top: 20px;
}

.nature-card {
    background-color: white;
    border-radius: 15px;
    overflow: hidden;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s;
    display: flex;
    flex-direction: column;
}

.nature-card:hover {
    transform: scale(1.02);
}

.nature-card img {
    width: 100%;
    height: 200px;
    object-fit: cover;
    cursor: pointer;
}

.nature-card .name {
    padding: 10px;
    text-align: center;
    font-size: 1.4em;
    color: #333;
    background-color: #E1F5FE;
    font-weight: bold;
}

.nature-card .description {
    padding: 10px;
    text-align: center;
    color: #666;
    font-size: 1em;
    background-color: #f8f8f8;
}

.speak-button {
    width: 100%;
    padding: 12px;
    background-color: #4CAF50;
    color: white;
    border: none;
    cursor: pointer;
    font-size: 1.1em;
    transition: background-color 0.3s;
    margin-top: auto;
}

.speak-button:hover {
    background-color: #388E3C;
}

/* Activity specific styles */
.word-card {
    display: inline-block;
    padding: 15px;
    margin: 10px;
    background-color: #E1F5FE;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.2s;
}

.word-card:hover {
    transform: scale(1.05);
}

.letter {
    font-size: 2em;
    color: #2196F3;
    margin: 10px;
    cursor: pointer;
}

.letter:hover {
    color: #0D47A1;
}

/* Recording controls */
.recording-controls {
    display: flex;
    justify-content: center;
    gap: 20px;
    margin: 20px 0;
    padding: 15px;
    background-color: #f8f8f8;
    border-radius: 15px;
    box-shadow: 0 2px 4px rgba(0,0,0,0.1);
}

.record-button, .play-button {
    padding: 12px 24px;
    font-size: 1.1em;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: flex;
    align-items: center;
    gap: 8px;
}

.record-button {
    background-color: #ff4444;
    color: white;
}

.record-button:hover {
    background-color: #cc0000;
}

.record-button.recording {
    animation: pulse 1.5s infinite;
    background-color: #cc0000;
}

.play-button {
    background-color: #4CAF50;
    color: white;
}

.play-button:hover {
    background-color: #388E3C;
}

.play-button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

@keyframes pulse {
    0% {
        transform: scale(1);
    }
    50% {
        transform: scale(1.05);
    }
    100% {
        transform: scale(1);
    }
}

/* Page content styles */
.page-content {
    background-color: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    margin: 20px 0;
}

.page-content h2 {
    color: #333;
    margin: 25px 0 15px;
    font-size: 1.5em;
}

.page-content h3 {
    color: #444;
    margin: 20px 0 10px;
    font-size: 1.3em;
}

.page-content p {
    line-height: 1.6;
    color: #666;
    margin-bottom: 15px;
}

.page-content ul {
    margin: 15px 0;
    padding-left: 20px;
}

.page-content li {
    margin: 10px 0;
    color: #666;
    line-height: 1.4;
}

/* Contact form styles */
.contact-form {
    max-width: 600px;
    margin: 30px auto;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 5px;
    color: #333;
    font-weight: bold;
}

.form-group input,
.form-group select,
.form-group textarea {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 8px;
    font-size: 1em;
}

.form-group textarea {
    resize: vertical;
    min-height: 100px;
}

.submit-button {
    background-color: #4CAF50;
    color: white;
    padding: 12px 24px;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1.1em;
    transition: background-color 0.3s;
}

.submit-button:hover {
    background-color: #388E3C;
}

/* Contact info styles */
.contact-info {
    margin-top: 40px;
    padding: 20px;
    background-color: #f8f8f8;
    border-radius: 10px;
}

.contact-info h3 {
    color: #333;
    margin-bottom: 15px;
}

.contact-info p {
    margin: 10px 0;
    color: #666;
}

/* Back button styles */
.back-button {
    margin: 30px 0;
    text-align: center;
}

.btn {
    display: inline-block;
    padding: 12px 24px;
    background-color: #FF9800;
    color: white;
    text-decoration: none;
    border-radius: 8px;
    transition: background-color 0.3s;
}

.btn:hover {
    background-color: #F57C00;
}

/* Terms and Privacy sections */
.terms-section,
.privacy-section,
.about-section {
    max-width: 800px;
    margin: 0 auto;
}

/* Responsive adjustments */
@media (max-width: 768px) {
    .page-content {
        padding: 20px;
    }

    .contact-form {
        padding: 0 15px;
    }

    .form-group input,
    .form-group select,
    .form-group textarea {
        font-size: 16px; /* Prevents zoom on mobile */
    }
}

/* Message styles */
.message {
    padding: 15px;
    margin: 20px 0;
    border-radius: 8px;
    text-align: center;
    font-weight: bold;
}

.message.success {
    background-color: #d4edda;
    color: #155724;
    border: 1px solid #c3e6cb;
}

.message.error {
    background-color: #f8d7da;
    color: #721c24;
    border: 1px solid #f5c6cb;
}

/* Auth Buttons */
.auth-buttons {
    position: absolute;
    top: 20px;
    right: 20px;
    display: flex;
    gap: 10px;
    z-index: 100;
}

.auth-btn {
    padding: 10px 20px;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-weight: bold;
    transition: all 0.3s ease;
}

#loginBtn {
    background-color: #4CAF50;
    color: white;
}

#registerBtn {
    background-color: #2196F3;
    color: white;
}

#logoutBtn {
    background-color: #f44336;
    color: white;
}

.auth-btn:hover {
    opacity: 0.9;
    transform: translateY(-2px);
}

/* Modal Styles */
.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    background-color: rgba(0,0,0,0.5);
}

.modal-content {
    background-color: #fefefe;
    margin: 15% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 80%;
    max-width: 500px;
    border-radius: 8px;
    position: relative;
}

.close {
    position: absolute;
    right: 20px;
    top: 10px;
    font-size: 28px;
    font-weight: bold;
    cursor: pointer;
}

.close:hover {
    color: #f44336;
}

/* Mobile Responsive Styles */
@media (max-width: 768px) {
    .container {
        padding: 10px;
        width: 100%;
    }

    header {
        padding: 15px;
        margin-bottom: 15px;
    }

    header h1 {
        font-size: 1.8em;
    }

    .slogan {
        font-size: 1em;
    }

    .activities {
        flex-direction: column;
        align-items: center;
        gap: 10px;
    }

    .activity-btn {
        width: 100%;
        max-width: 300px;
        padding: 12px;
        font-size: 1em;
    }

    .activity-content {
        padding: 10px;
        margin: 10px 0;
    }

    .progress-section {
        padding: 0 10px;
    }

    .progress-bar {
        height: 15px;
    }

    .features {
        grid-template-columns: 1fr;
        gap: 15px;
        padding: 0 10px;
    }

    .feature-card {
        padding: 15px;
    }

    .main-nav {
        flex-direction: column;
        align-items: center;
        gap: 10px;
    }

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

    footer {
        padding: 20px 10px;
    }

    .footer-content {
        flex-direction: column;
        align-items: center;
        text-align: center;
        gap: 20px;
    }

    .footer-section {
        width: 100%;
        margin-bottom: 15px;
    }

    /* Hide elements that might be too small on mobile */
    .activity-content:empty {
        display: none;
    }
}

/* Small mobile devices */
@media (max-width: 480px) {
    header h1 {
        font-size: 1.5em;
    }

    .slogan {
        font-size: 0.9em;
    }

    .activity-btn {
        font-size: 0.9em;
        padding: 10px;
    }

    .feature-card h3 {
        font-size: 1.1em;
    }

    .feature-card p {
        font-size: 0.9em;
    }
}

/* Landscape mode for mobile */
@media (max-height: 500px) and (orientation: landscape) {
    .activities {
        flex-direction: row;
        flex-wrap: wrap;
    }

    .activity-btn {
        width: auto;
        min-width: 120px;
    }
}

.features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
    margin: 40px 0;
    padding: 30px 20px;
    max-width: 1400px;
    margin-left: auto;
    margin-right: auto;
}

.feature-card {
    background: linear-gradient(135deg, #ffffff 0%, #f8f9fa 100%);
    padding: 35px 25px;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08), 0 1px 3px rgba(0, 0, 0, 0.05);
    text-align: center;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    position: relative;
    overflow: hidden;
    border: 1px solid rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(10px);
    min-height: 220px;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
}

.feature-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 4px;
    background: linear-gradient(90deg, #4CAF50, #2196F3, #9C27B0, #FF9800);
    background-size: 200% 100%;
    transform: scaleX(0);
    transition: transform 0.4s ease;
    animation: gradient-shift 3s ease infinite;
}

@keyframes gradient-shift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.feature-card::after {
    content: '';
    position: absolute;
    top: -50%;
    right: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(76, 175, 80, 0.1) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.4s ease;
    pointer-events: none;
}

.feature-card:hover {
    transform: translateY(-10px) scale(1.02);
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15), 0 5px 15px rgba(76, 175, 80, 0.2);
    border-color: rgba(76, 175, 80, 0.3);
}

.feature-card:hover::before {
    transform: scaleX(1);
}

.feature-card:hover::after {
    opacity: 1;
}

.feature-card.new-game {
    grid-column: 1 / -1;
    max-width: 420px;
    width: 100%;
    justify-self: center;
}

.feature-card.contact-card {
    margin-top: 40px;
}

/* Add subtle animation on card load */
@keyframes cardFadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feature-card {
    animation: cardFadeIn 0.6s ease-out;
}

.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }
.feature-card:nth-child(4) { animation-delay: 0.4s; }
.feature-card:nth-child(5) { animation-delay: 0.5s; }
.feature-card:nth-child(6) { animation-delay: 0.6s; }
.feature-card:nth-child(7) { animation-delay: 0.7s; }
.feature-card:nth-child(8) { animation-delay: 0.8s; }

/* Add subtle animation on card load */
@keyframes cardFadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feature-card {
    animation: cardFadeIn 0.6s ease-out;
}

.feature-card:nth-child(1) { animation-delay: 0.1s; }
.feature-card:nth-child(2) { animation-delay: 0.2s; }
.feature-card:nth-child(3) { animation-delay: 0.3s; }
.feature-card:nth-child(4) { animation-delay: 0.4s; }
.feature-card:nth-child(5) { animation-delay: 0.5s; }
.feature-card:nth-child(6) { animation-delay: 0.6s; }
.feature-card:nth-child(7) { animation-delay: 0.7s; }
.feature-card:nth-child(8) { animation-delay: 0.8s; }

/* Store page */
.store-container {
    gap: 20px;
}

.store-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 15px;
}

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

.store-content {
    display: flex;
    flex-direction: column;
    gap: 40px;
}

.store-hero {
    display: flex;
    flex-wrap: wrap;
    gap: 30px;
    align-items: stretch;
    background: linear-gradient(135deg, #e3f2fd, #fce4ec);
    padding: 25px;
    border-radius: 20px;
    margin-bottom: 30px;
}

.store-hero > div {
    flex: 1;
    min-width: 260px;
}

.store-hero-highlight {
    background: #fff;
    border-radius: 15px;
    padding: 20px;
    box-shadow: 0 10px 30px rgba(0,0,0,0.1);
}

.store-hero-title {
    font-size: 1.4em;
    font-weight: 700;
}

.store-hero-subtitle {
    color: #388e3c;
    font-weight: 600;
}

.store-hero-note {
    margin-top: 10px;
    padding: 10px;
    background: #f5f5f5;
    border-radius: 10px;
    font-size: 0.95em;
}

.store-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 20px;
}

.store-card {
    background: #fff;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.store-card img {
    width: 100%;
    height: 220px;
    object-fit: cover;
}

.store-card-body {
    padding: 20px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.store-prices {
    display: flex;
    align-items: baseline;
    gap: 10px;
}

.store-old-price {
    text-decoration: line-through;
    color: #9e9e9e;
}

.store-price {
    color: #d32f2f;
    font-size: 1.2em;
    font-weight: bold;
}

.store-banner {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
    gap: 20px;
    padding: 25px;
    border-radius: 25px;
    background: linear-gradient(120deg, #fff3e0, #ffe0f0);
    align-items: center;
}

.store-banner-content h2 {
    margin: 10px 0;
    font-size: 2rem;
    color: #c62828;
}

.store-banner img {
    width: 100%;
    border-radius: 18px;
    object-fit: cover;
    min-height: 220px;
}

.store-banner-tag {
    font-weight: 700;
    color: #ef6c00;
    letter-spacing: 1px;
    text-transform: uppercase;
}

.store-section h3 {
    text-transform: uppercase;
    text-align: center;
    font-size: 1.6rem;
    margin-bottom: 20px;
}

.store-category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}

.store-category {
    background: #fff;
    border-radius: 16px;
    box-shadow: 0 8px 25px rgba(0,0,0,0.08);
    padding: 15px;
    display: flex;
    flex-direction: column;
    gap: 10px;
    align-items: center;
    text-align: center;
}

.store-category img {
    width: 100%;
    height: 120px;
    object-fit: cover;
    border-radius: 12px;
}

.ghost-btn {
    background: transparent;
    border: 1px solid #4CAF50;
    color: #4CAF50;
}

.store-carousel {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
}

.store-chip {
    align-self: flex-start;
    padding: 3px 10px;
    border-radius: 999px;
    background: #ff7043;
    color: #fff;
    font-size: 0.8em;
    text-transform: uppercase;
}

.store-info-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    gap: 20px;
    background: #f5f5f5;
    padding: 20px;
    border-radius: 15px;
}

.store-info-grid article {
    background: #fff;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 6px 16px rgba(0,0,0,0.08);
}

.store-info-grid a {
    color: #1976d2;
    text-decoration: underline;
}

@media (max-width: 768px) {
    .store-banner-content h2 {
        font-size: 1.5rem;
    }
}

.feature-card h3 {
    margin-bottom: 15px;
    color: #333;
    font-size: 1.4em;
    position: relative;
    padding-bottom: 10px;
}

.feature-card h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 3px;
    background: linear-gradient(90deg, #4CAF50, #2196F3);
    border-radius: 3px;
}

.feature-card p {
    margin-bottom: 20px;
    color: #666;
    line-height: 1.6;
    font-size: 1.1em;
}

.feature-card .btn {
    display: inline-block;
    padding: 12px 25px;
    background: linear-gradient(45deg, #4CAF50, #2196F3);
    color: white;
    text-decoration: none;
    border-radius: 30px;
    transition: all 0.3s ease;
    border: none;
    font-weight: 500;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.feature-card .btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 12px rgba(0,0,0,0.15);
    background: linear-gradient(45deg, #2196F3, #4CAF50);
}

/* Feature card icons */
.feature-card::after {
    content: '';
    position: absolute;
    bottom: -50px;
    right: -50px;
    width: 100px;
    height: 100px;
    background: rgba(76, 175, 80, 0.1);
    border-radius: 50%;
    transition: all 0.3s ease;
}

.feature-card:hover::after {
    transform: scale(1.2);
    background: rgba(33, 150, 243, 0.1);
}

/* Responsive adjustments for features */
@media (max-width: 1200px) {
    .features {
        grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
        gap: 25px;
        padding: 25px 15px;
    }
}

@media (max-width: 768px) {
    .features {
        grid-template-columns: 1fr;
        gap: 25px;
        padding: 20px 15px;
        margin: 30px 0;
    }

    .feature-card {
        padding: 30px 20px;
        min-height: auto;
    }

    .feature-card h3 {
        font-size: 1.4em;
        margin-bottom: 12px;
    }

    .feature-card p {
        font-size: 1em;
        margin-bottom: 20px;
    }

    .feature-card .btn {
        padding: 12px 25px;
        font-size: 0.95em;
    }
}

@media (max-width: 480px) {
    .features {
        gap: 20px;
        padding: 15px 10px;
    }

    .feature-card {
        padding: 25px 15px;
        border-radius: 15px;
    }

    .feature-card h3 {
        font-size: 1.3em;
    }

    .feature-card p {
        font-size: 0.95em;
    }
}

.premium-btn {
    display: inline-block;
    padding: 12px 24px;
    background: linear-gradient(45deg, #FFD700, #FFA500);
    color: #fff;
    text-decoration: none;
    border-radius: 30px;
    font-weight: bold;
    font-size: 1.1em;
    margin-top: 20px;
    box-shadow: 0 4px 15px rgba(255, 165, 0, 0.3);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.premium-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(255, 165, 0, 0.4);
}

.premium-btn:active {
    transform: translateY(1px);
    box-shadow: 0 2px 10px rgba(255, 165, 0, 0.3);
}

.ad-container {
    margin: 20px auto;
    padding: 10px;
    text-align: center;
    max-width: 100%;
    min-height: 90px;
    background-color: #f8f9fa;
    border-radius: 8px;
}

@media (max-width: 768px) {
    .ad-container {
        margin: 15px auto;
        padding: 5px;
    }
}

/* Common styles */
.back-btn {
    display: inline-block;
    padding: 10px 20px;
    background-color: #4CAF50;
    color: white;
    text-decoration: none;
    border-radius: 5px;
    margin: 20px 0;
    transition: background-color 0.3s;
}

.back-btn:hover {
    background-color: #45a049;
}

/* Alphabet page styles */
.alphabet-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(80px, 1fr));
    gap: 15px;
    padding: 20px;
}

.letter {
    background-color: #4CAF50;
    color: white;
    font-size: 2em;
    font-weight: bold;
    padding: 20px;
    text-align: center;
    border-radius: 10px;
    cursor: pointer;
    transition: transform 0.3s, background-color 0.3s;
}

.letter:hover {
    transform: scale(1.1);
    background-color: #45a049;
}

/* Words page styles */
.words-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
    padding: 20px;
}

.word-card {
    background-color: white;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.word {
    font-size: 1.5em;
    margin-bottom: 15px;
    color: #333;
}

/* Phrases page styles */
.phrases-container {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
    gap: 20px;
    padding: 20px;
}

.phrase-card {
    background-color: white;
    border-radius: 10px;
    padding: 20px;
    text-align: center;
    box-shadow: 0 4px 8px rgba(0,0,0,0.1);
    transition: transform 0.3s;
}

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

.phrase {
    font-size: 1.3em;
    margin-bottom: 15px;
    color: #333;
}

/* Button styles */
.speak-button {
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 1em;
    transition: background-color 0.3s;
}

.speak-button:hover {
    background-color: #45a049;
}

/* Responsive styles */
@media (max-width: 768px) {
    .alphabet-container {
        grid-template-columns: repeat(auto-fill, minmax(60px, 1fr));
    }

    .words-container,
    .phrases-container {
        grid-template-columns: 1fr;
    }

    .letter {
        font-size: 1.5em;
        padding: 15px;
    }

    .word,
    .phrase {
        font-size: 1.2em;
    }
}