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

:root {
    --primary-color: #3b82f6;
    --primary-hover: #2563eb;
    --secondary-color: #64748b;
    --background: #ffffff;
    --surface: #f8fafc;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --border: #e2e8f0;
    --success: #10b981;
    --error: #ef4444;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    --radius: 0.5rem;
    --transition: all 0.3s ease;
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--background);
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
}

/* Header Styles */
.header {
    background: var(--background);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 100;
    backdrop-filter: blur(10px);
    background: rgba(255, 255, 255, 0.95);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 4rem;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--primary-color);
}

.nav-logo i {
    font-size: 1.5rem;
}

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

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

.nav-link:hover,
.nav-link.active {
    color: var(--primary-color);
}

.nav-link.active::after {
    content: '';
    position: absolute;
    bottom: -1rem;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--primary-color);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    cursor: pointer;
    gap: 0.25rem;
}

.bar {
    width: 1.5rem;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* Main Content */
.main {
    min-height: calc(100vh - 8rem);
}

.page {
    display: none;
    padding: 2rem 0;
}

.page.active {
    display: block;
}

/* Home Page Styles */
.hero {
    text-align: center;
    margin-bottom: 3rem;
    padding: 2rem 0;
}

.hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    background: linear-gradient(135deg, var(--primary-color), #8b5cf6);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: 1.125rem;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Translator Container */
.translator-container {
    background: var(--surface);
    border-radius: var(--radius);
    padding: 2rem;
    margin-bottom: 3rem;
    box-shadow: var(--shadow-md);
}

.language-selector {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 1rem;
    margin-bottom: 2rem;
}

.lang-box {
    flex: 1;
    max-width: 200px;
}

.lang-select {
    width: 100%;
    padding: 0.75rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    font-size: 1rem;
    font-weight: 500;
    background: var(--background);
    cursor: pointer;
    transition: var(--transition);
}

.lang-select:focus {
    outline: none;
    border-color: var(--primary-color);
}

.swap-btn {
    padding: 0.75rem;
    background: var(--primary-color);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.swap-btn:hover {
    background: var(--primary-hover);
    transform: rotate(180deg);
}

.translation-area {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 2rem;
    margin-bottom: 2rem;
}

.input-section,
.output-section {
    position: relative;
}

.textarea-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 0.5rem;
}

.label {
    font-weight: 600;
    color: var(--text-primary);
}

.char-count {
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.text-input {
    width: 100%;
    min-height: 150px;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    font-size: 1rem;
    font-family: inherit;
    resize: vertical;
    transition: var(--transition);
}

.text-input:focus {
    outline: none;
    border-color: var(--primary-color);
}

.translation-result {
    min-height: 150px;
    padding: 1rem;
    border: 2px solid var(--border);
    border-radius: var(--radius);
    background: var(--background);
    font-size: 1rem;
    line-height: 1.6;
}

.placeholder {
    color: var(--text-secondary);
    font-style: italic;
}

.input-actions {
    display: flex;
    gap: 0.5rem;
    margin-top: 0.5rem;
}

.output-actions {
    display: flex;
    gap: 0.5rem;
}

.btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
}

.btn-primary {
    background: var(--primary-color);
    color: white;
}

.btn-primary:hover {
    background: var(--primary-hover);
    transform: translateY(-1px);
}

.btn-secondary {
    background: var(--surface);
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-secondary:hover {
    background: var(--border);
}

.btn-icon {
    padding: 0.5rem;
    background: transparent;
    color: var(--text-secondary);
    border: 1px solid var(--border);
}

.btn-icon:hover {
    background: var(--surface);
    color: var(--primary-color);
}

.translate-btn {
    width: 100%;
    padding: 1rem;
    font-size: 1.125rem;
    justify-content: center;
}

/* Features Section */
.features {
    margin-top: 3rem;
}

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

.feature-card {
    text-align: center;
    padding: 2rem;
    background: var(--surface);
    border-radius: var(--radius);
    transition: var(--transition);
}

.feature-card:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.feature-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.25rem;
    margin-bottom: 0.5rem;
}

.feature-card p {
    color: var(--text-secondary);
}

/* About Page Styles */
.page-title {
    font-size: 2.5rem;
    font-weight: 700;
    text-align: center;
    margin-bottom: 3rem;
    color: var(--text-primary);
}

.about-content {
    max-width: 800px;
    margin: 0 auto;
}

.about-section {
    margin-bottom: 3rem;
}

.about-section h2 {
    font-size: 1.875rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.about-section p {
    font-size: 1.125rem;
    line-height: 1.7;
    color: var(--text-secondary);
}

.feature-list {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.feature-item {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-size: 1.125rem;
}

.feature-item i {
    color: var(--success);
    font-size: 1.25rem;
}

.contact-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.contact-link:hover {
    text-decoration: underline;
}

/* Footer */
.footer {
    background: var(--surface);
    border-top: 1px solid var(--border);
    padding: 2rem 0;
    text-align: center;
    color: var(--text-secondary);
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        position: fixed;
        left: -100%;
        top: 4rem;
        flex-direction: column;
        background: var(--background);
        width: 100%;
        text-align: center;
        transition: var(--transition);
        box-shadow: var(--shadow-lg);
        padding: 2rem 0;
        gap: 0;
    }

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

    .nav-item {
        margin: 1rem 0;
    }

    .nav-toggle {
        display: flex;
    }

    .nav-toggle.active .bar:nth-child(2) {
        opacity: 0;
    }

    .nav-toggle.active .bar:nth-child(1) {
        transform: translateY(8px) rotate(45deg);
    }

    .nav-toggle.active .bar:nth-child(3) {
        transform: translateY(-8px) rotate(-45deg);
    }

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

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

    .translation-area {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

    .language-selector {
        flex-direction: column;
        gap: 1rem;
    }

    .lang-box {
        max-width: 100%;
    }

    .swap-btn {
        transform: rotate(90deg);
    }

    .swap-btn:hover {
        transform: rotate(270deg);
    }

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

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

    .about-section h2 {
        font-size: 1.5rem;
    }

    .about-section p,
    .feature-item {
        font-size: 1rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 0.75rem;
    }

    .translator-container {
        padding: 1.5rem;
    }

    .hero {
        margin-bottom: 2rem;
        padding: 1rem 0;
    }

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

    .input-actions {
        flex-wrap: wrap;
    }

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

/* Loading and Animation States */
.loading {
    opacity: 0.6;
    pointer-events: none;
}

.translating {
    position: relative;
}

.translating::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(255, 255, 255, 0.8);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: var(--radius);
}

.spinner {
    width: 20px;
    height: 20px;
    border: 2px solid var(--border);
    border-top: 2px solid var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

/* Enhanced UI Styles */
.hero-keywords {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem;
    justify-content: center;
    margin-top: 1.5rem;
}

.keyword-tag {
    background: linear-gradient(135deg, var(--primary-color), #8b5cf6);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: 2rem;
    font-size: 0.875rem;
    font-weight: 500;
    animation: fadeInUp 0.6s ease;
}

.features-title {
    text-align: center;
    font-size: 2rem;
    font-weight: 700;
    margin-bottom: 2rem;
    color: var(--text-primary);
}

.seo-content {
    margin-top: 4rem;
    padding: 3rem 2rem;
    background: var(--surface);
    border-radius: var(--radius);
    box-shadow: var(--shadow-md);
}

.seo-title {
    font-size: 1.875rem;
    font-weight: 700;
    margin-bottom: 2rem;
    color: var(--primary-color);
    text-align: center;
}

.seo-text {
    font-size: 1.125rem;
    line-height: 1.8;
    color: var(--text-secondary);
}

.seo-text h3 {
    font-size: 1.5rem;
    margin: 2rem 0 1rem;
    color: var(--text-primary);
}

.seo-text ul {
    margin: 1rem 0;
    padding-left: 2rem;
}

.seo-text li {
    margin-bottom: 0.5rem;
    line-height: 1.6;
}

.seo-text strong {
    color: var(--primary-color);
    font-weight: 600;
}

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

.footer-section h3,
.footer-section h4 {
    color: var(--text-primary);
    margin-bottom: 1rem;
    font-weight: 600;
}

.footer-section ul {
    list-style: none;
    padding: 0;
}

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

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

.footer-section a:hover {
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid var(--border);
    padding-top: 1rem;
    text-align: center;
    color: var(--text-secondary);
}

.footer-bottom p {
    margin-bottom: 0.5rem;
    font-size: 0.875rem;
}

/* Enhanced Language Selector */
.lang-select {
    font-size: 1rem;
    font-weight: 500;
    padding: 0.75rem 2rem 0.75rem 1rem;
    background-image: url("data:image/svg+xml;charset=UTF-8,%3csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='currentColor' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3e%3cpolyline points='6,9 12,15 18,9'%3e%3c/polyline%3e%3c/svg%3e");
    background-repeat: no-repeat;
    background-position: right 0.5rem center;
    background-size: 1.5em 1.5em;
    padding-right: 2.5rem;
}

/* Animations */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

.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; }

/* Enhanced Mobile Responsiveness */
@media (max-width: 768px) {
    .hero-keywords {
        gap: 0.25rem;
    }
    
    .keyword-tag {
        font-size: 0.75rem;
        padding: 0.375rem 0.75rem;
    }
    
    .seo-content {
        padding: 2rem 1rem;
    }
    
    .seo-title {
        font-size: 1.5rem;
    }
    
    .seo-text {
        font-size: 1rem;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
}