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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: #333;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    overflow-x: hidden;
}

/* Animated background particles */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"><animate attributeName="cy" values="20;80;20" dur="3s" repeatCount="indefinite"/></circle><circle cx="50" cy="50" r="1.5" fill="rgba(255,255,255,0.08)"><animate attributeName="cy" values="50;10;50" dur="4s" repeatCount="indefinite"/></circle><circle cx="80" cy="30" r="1" fill="rgba(255,255,255,0.06)"><animate attributeName="cy" values="30;90;30" dur="5s" repeatCount="indefinite"/></circle></svg>') repeat;
    pointer-events: none;
    z-index: -1;
}

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

/* Header Styles */
.header {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    box-shadow: 0 2px 20px rgba(0, 0, 0, 0.1);
}

.navbar {
    padding: 1rem 0;
}

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

.nav-logo {
    display: flex;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: #667eea;
}

.nav-logo i {
    margin-right: 0.5rem;
    font-size: 1.8rem;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 2rem;
}

.nav-menu a {
    text-decoration: none;
    color: #333;
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-menu a:hover {
    color: #667eea;
}

.language-selector select {
    padding: 0.5rem;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    background: white;
    color: #333;
    font-size: 0.9rem;
    cursor: pointer;
    transition: border-color 0.3s ease;
}

.language-selector select:focus {
    outline: none;
    border-color: #667eea;
}

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

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: #333;
    margin: 3px 0;
    transition: 0.3s;
}

/* Hero Section */
.hero {
    padding: 120px 0 80px;
    text-align: center;
    color: white;
}

.hero-content h1 {
    font-size: 3.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.hero-content p {
    font-size: 1.2rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: 3rem;
    margin-top: 3rem;
}

.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5rem;
}

.feature-item i {
    font-size: 2rem;
    margin-bottom: 0.5rem;
}

.feature-item span {
    font-weight: 600;
}

/* Converter Section */
.converter-section {
    padding: 80px 0;
    background: rgba(255, 255, 255, 0.1);
}

.converter-card {
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(20px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    padding: 3rem;
    box-shadow: 
        0 20px 60px rgba(0, 0, 0, 0.1),
        0 0 0 1px rgba(255, 255, 255, 0.1) inset;
    position: relative;
    overflow: hidden;
}

.converter-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.2), transparent);
    transition: left 0.5s ease;
}

.converter-card:hover::before {
    left: 100%;
}

.converter-header {
    text-align: center;
    margin-bottom: 3rem;
}

.converter-header h2 {
    font-size: 2.5rem;
    color: #333;
    margin-bottom: 1rem;
}

.converter-header p {
    font-size: 1.1rem;
    color: #666;
}

/* Upload Area */
.upload-area {
    border: 3px dashed #667eea;
    border-radius: 15px;
    padding: 3rem;
    text-align: center;
    background: linear-gradient(135deg, #f8f9ff 0%, #e8ebff 100%);
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    margin-bottom: 2rem;
    overflow: hidden;
}

.upload-area::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: radial-gradient(circle, rgba(102, 126, 234, 0.1) 0%, transparent 70%);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: all 0.3s ease;
    z-index: 1;
}

.upload-area:hover {
    border-color: #5a6fd8;
    background: linear-gradient(135deg, #f0f2ff 0%, #e0e4ff 100%);
    transform: translateY(-2px);
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.2);
}

.upload-area:hover::before {
    width: 200px;
    height: 200px;
}

.upload-area.dragover {
    border-color: #4c63d2;
    background: linear-gradient(135deg, #e8ebff 0%, #d8dcff 100%);
    transform: scale(1.02);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.3);
}

.upload-area.dragover::before {
    width: 300px;
    height: 300px;
}

.upload-content {
    position: relative;
    z-index: 2;
}

.upload-content i {
    font-size: 4rem;
    color: #667eea;
    margin-bottom: 1rem;
    transition: all 0.3s ease;
}

.upload-area:hover .upload-content i {
    transform: scale(1.1);
    color: #5a6fd8;
}

.upload-content h3 {
    font-size: 1.5rem;
    color: #333;
    margin-bottom: 0.5rem;
    transition: color 0.3s ease;
}

.upload-area:hover .upload-content h3 {
    color: #4c63d2;
}

.upload-content p {
    color: #666;
    font-size: 1rem;
}

#fileInput {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    opacity: 0;
    cursor: pointer;
}

/* File List */
.file-list {
    background: #f8f9ff;
    border-radius: 15px;
    padding: 2rem;
    margin-bottom: 2rem;
}

.file-list h3 {
    color: #333;
    margin-bottom: 1rem;
}

.file-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 1rem;
    background: white;
    border-radius: 10px;
    margin-bottom: 1rem;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.05);
}

.file-info {
    display: flex;
    align-items: center;
    gap: 1rem;
}

.file-info i {
    font-size: 1.5rem;
    color: #667eea;
}

.file-details h4 {
    color: #333;
    font-size: 1rem;
}

.file-details p {
    color: #666;
    font-size: 0.9rem;
}

.file-remove {
    background: #ff4757;
    color: white;
    border: none;
    border-radius: 50%;
    width: 30px;
    height: 30px;
    cursor: pointer;
    transition: background 0.3s ease;
}

.file-remove:hover {
    background: #ff3742;
}

/* Format Selection */
.format-selection {
    margin-bottom: 2rem;
}

.format-group {
    margin-bottom: 2rem;
}

.format-group label {
    display: block;
    font-weight: 600;
    color: #333;
    margin-bottom: 0.5rem;
}

.format-group select {
    width: 100%;
    padding: 1rem;
    border: 2px solid #e1e5e9;
    border-radius: 10px;
    font-size: 1rem;
    background: white;
    cursor: pointer;
    transition: border-color 0.3s ease;
}

.format-group select:focus {
    outline: none;
    border-color: #667eea;
}

/* Advanced Options */
.advanced-options {
    background: #f8f9ff;
    border-radius: 15px;
    padding: 2rem;
    margin-top: 2rem;
}

.advanced-options h4 {
    color: #333;
    margin-bottom: 1.5rem;
    font-size: 1.2rem;
}

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

.option-group label {
    display: block;
    font-weight: 600;
    color: #333;
    margin-bottom: 0.5rem;
}

.option-group select {
    width: 100%;
    padding: 0.8rem;
    border: 2px solid #e1e5e9;
    border-radius: 8px;
    font-size: 0.9rem;
    background: white;
    cursor: pointer;
    transition: border-color 0.3s ease;
}

.option-group select:focus {
    outline: none;
    border-color: #667eea;
}

/* Convert Button */
.convert-section {
    text-align: center;
}

.convert-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border: none;
    padding: 1.2rem 3rem;
    font-size: 1.1rem;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: all 0.3s ease;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    box-shadow: 0 10px 30px rgba(102, 126, 234, 0.3);
}

.convert-btn:hover:not(:disabled) {
    transform: translateY(-2px);
    box-shadow: 0 15px 40px rgba(102, 126, 234, 0.4);
}

.convert-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.convert-btn i {
    font-size: 1.2rem;
}

/* Progress Bar */
.progress-bar {
    width: 100%;
    height: 12px;
    background: linear-gradient(90deg, #e1e5e9 0%, #f0f2f5 100%);
    border-radius: 6px;
    margin-top: 2rem;
    position: relative;
    overflow: hidden;
    box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.1);
}

.progress-fill {
    height: 100%;
    background: linear-gradient(90deg, #667eea 0%, #764ba2 50%, #667eea 100%);
    background-size: 200% 100%;
    border-radius: 6px;
    width: 0%;
    transition: width 0.3s ease;
    position: relative;
    animation: shimmer 2s infinite;
}

@keyframes shimmer {
    0% { background-position: -200% 0; }
    100% { background-position: 200% 0; }
}

.progress-fill::after {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: linear-gradient(90deg, transparent 0%, rgba(255, 255, 255, 0.3) 50%, transparent 100%);
    animation: progressGlow 1.5s ease-in-out infinite;
}

@keyframes progressGlow {
    0%, 100% { transform: translateX(-100%); }
    50% { transform: translateX(100%); }
}

.progress-text {
    position: absolute;
    top: -35px;
    left: 50%;
    transform: translateX(-50%);
    font-weight: 600;
    color: #333;
    background: rgba(255, 255, 255, 0.9);
    padding: 0.3rem 0.8rem;
    border-radius: 15px;
    font-size: 0.9rem;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

/* Download Section */
.download-section {
    text-align: center;
    padding: 2rem;
    background: #f0f8ff;
    border-radius: 15px;
    margin-top: 2rem;
}

.download-section h3 {
    color: #333;
    margin-bottom: 1.5rem;
    font-size: 1.5rem;
}

.download-link {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: #28a745;
    color: white;
    text-decoration: none;
    padding: 1rem 2rem;
    border-radius: 10px;
    margin: 0.5rem;
    transition: background 0.3s ease;
    font-weight: 600;
}

.download-link:hover {
    background: #218838;
}

.download-link i {
    font-size: 1.2rem;
}

.download-all-btn {
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    background: #667eea;
    color: white;
    border: none;
    padding: 1rem 2rem;
    border-radius: 10px;
    margin: 0.5rem;
    transition: background 0.3s ease;
    font-weight: 600;
    cursor: pointer;
    font-size: 1rem;
}

.download-all-btn:hover {
    background: #5a6fd8;
}

.download-all-btn i {
    font-size: 1.2rem;
}

/* Formats Section */
.formats-section {
    padding: 80px 0;
    background: rgba(255, 255, 255, 0.1);
    text-align: center;
}

.formats-section h2 {
    font-size: 2.5rem;
    color: white;
    margin-bottom: 3rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.3);
}

.formats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 2rem;
    margin-bottom: 3rem;
}

.format-card {
    background: white;
    padding: 2rem;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease;
}

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

.format-card i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.format-card h3 {
    font-size: 1.5rem;
    color: #333;
    margin-bottom: 0.5rem;
}

.format-card p {
    color: #666;
    font-size: 0.9rem;
}

.formats-note {
    color: white;
    font-size: 1.1rem;
    opacity: 0.9;
    max-width: 800px;
    margin: 0 auto;
}

/* Features Section */
.features-section {
    padding: 80px 0;
    background: white;
}

.features-section h2 {
    font-size: 2.5rem;
    color: #333;
    text-align: center;
    margin-bottom: 3rem;
}

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

.feature-card {
    text-align: center;
    padding: 2rem;
    border-radius: 15px;
    background: #f8f9ff;
    transition: transform 0.3s ease;
}

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

.feature-card i {
    font-size: 3rem;
    color: #667eea;
    margin-bottom: 1rem;
}

.feature-card h3 {
    font-size: 1.3rem;
    color: #333;
    margin-bottom: 1rem;
}

.feature-card p {
    color: #666;
    line-height: 1.6;
}

/* Footer */
.footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0 1rem;
}

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

.footer-section h3,
.footer-section h4 {
    margin-bottom: 1rem;
    color: #ecf0f1;
}

.footer-section p {
    color: #bdc3c7;
    line-height: 1.6;
}

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

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

.footer-section ul li a {
    color: #bdc3c7;
    text-decoration: none;
    transition: color 0.3s ease;
}

.footer-section ul li a:hover {
    color: #667eea;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: #34495e;
    color: white;
    border-radius: 50%;
    text-decoration: none;
    transition: background 0.3s ease;
}

.social-links a:hover {
    background: #667eea;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #34495e;
    color: #bdc3c7;
}

/* Responsive Design */
@media (max-width: 768px) {
    .nav-menu {
        display: none;
    }
    
    .nav-toggle {
        display: flex;
    }
    
    .hero-content h1 {
        font-size: 2.5rem;
    }
    
    .hero-features {
        flex-direction: column;
        gap: 1.5rem;
    }
    
    .converter-card {
        padding: 2rem 1.5rem;
    }
    
    .options-grid {
        grid-template-columns: 1fr;
    }
    
    .formats-grid {
        grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 15px;
    }
    
    .hero {
        padding: 100px 0 60px;
    }
    
    .hero-content h1 {
        font-size: 2rem;
    }
    
    .converter-card {
        padding: 1.5rem 1rem;
    }
    
    .upload-area {
        padding: 2rem 1rem;
    }
    
    .upload-content i {
        font-size: 3rem;
    }
}

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

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

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

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

.convert-btn.loading i {
    animation: spin 1s linear infinite;
}

/* Smooth Scrolling */
html {
    scroll-behavior: smooth;
}