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

:root {
    --primary-color: #4F46E5;
    --primary-hover: #4338CA;
    --success-color: #10B981;
    --danger-color: #EF4444;
    --bg-color: #F9FAFB;
    --card-bg: #FFFFFF;
    --text-primary: #111827;
    --text-secondary: #6B7280;
    --border-color: #E5E7EB;
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
    --radius: 12px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
    color: var(--text-primary);
}

.container {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow-lg);
    max-width: 900px;
    width: 100%;
    overflow: hidden;
}

.header {
    background: linear-gradient(135deg, var(--primary-color), var(--primary-hover));
    color: white;
    padding: 40px 30px;
    text-align: center;
}

.title {
    font-size: 32px;
    font-weight: 700;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
}

.logo {
    width: 36px;
    height: 36px;
}

.subtitle {
    font-size: 16px;
    opacity: 0.9;
    margin-bottom: 20px;
}

.language-selector {
    display: flex;
    gap: 10px;
    justify-content: center;
}

.lang-btn {
    background: rgba(255, 255, 255, 0.2);
    border: 1px solid rgba(255, 255, 255, 0.3);
    color: white;
    padding: 8px 16px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 14px;
}

.lang-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

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

.main {
    padding: 40px 30px;
}

.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius);
    padding: 60px 20px;
    text-align: center;
    transition: all 0.3s;
    cursor: pointer;
    background: var(--bg-color);
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary-color);
    background: linear-gradient(to bottom, rgba(79, 70, 229, 0.05), rgba(79, 70, 229, 0.02));
}

.upload-icon {
    width: 64px;
    height: 64px;
    margin: 0 auto 20px;
    stroke: var(--primary-color);
}

.upload-area h2 {
    font-size: 24px;
    margin-bottom: 10px;
    color: var(--text-primary);
}

.upload-area p {
    color: var(--text-secondary);
    margin-bottom: 20px;
}

.btn {
    padding: 12px 24px;
    border-radius: 8px;
    border: none;
    cursor: pointer;
    font-size: 16px;
    font-weight: 500;
    transition: all 0.3s;
    display: inline-block;
}

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

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

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

.btn-success:hover {
    background: #059669;
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

.btn-small {
    padding: 6px 12px;
    font-size: 14px;
}

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

.checkbox-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    color: var(--text-secondary);
    transition: color 0.3s;
}

.checkbox-label:hover {
    color: var(--text-primary);
}

.checkbox-label input[type="checkbox"] {
    width: 18px;
    height: 18px;
    cursor: pointer;
    accent-color: var(--primary-color);
}

.mode-toggle {
    display: flex;
    gap: 10px;
    justify-content: center;
    margin: 30px 0;
}

.mode-btn {
    padding: 10px 20px;
    border: 2px solid var(--border-color);
    background: white;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.3s;
    font-size: 15px;
    font-weight: 500;
}

.mode-btn:hover {
    border-color: var(--primary-color);
}

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

.file-list {
    margin: 30px 0;
}

.results {
    background: var(--bg-color);
    border-radius: var(--radius);
    padding: 30px;
    margin-top: 30px;
}

.results h3 {
    font-size: 20px;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.result-item {
    background: white;
    border-radius: 8px;
    padding: 15px;
    margin-bottom: 10px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    box-shadow: var(--shadow-sm);
    transition: all 0.3s;
}

.result-item:hover {
    box-shadow: var(--shadow-md);
}

.file-info {
    flex: 1;
}

.file-name {
    font-weight: 600;
    color: var(--text-primary);
    display: block;
    margin-bottom: 5px;
}

.file-stats {
    font-size: 14px;
    color: var(--text-secondary);
    display: flex;
    gap: 15px;
}

.compression-rate {
    font-weight: 600;
}

.compression-rate.success {
    color: var(--success-color);
}

.stats {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 20px;
    margin: 30px 0;
    padding: 20px;
    background: white;
    border-radius: 8px;
}

.stat {
    text-align: center;
}

.stat span {
    display: block;
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 5px;
}

.stat strong {
    font-size: 20px;
    color: var(--text-primary);
}

.stat .success {
    color: var(--success-color);
}

.footer {
    background: var(--bg-color);
    padding: 20px;
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
}

.hidden {
    display: none;
}

@media (max-width: 640px) {
    .title {
        font-size: 24px;
    }
    
    .upload-area {
        padding: 40px 20px;
    }
    
    .options {
        flex-direction: column;
        align-items: center;
    }
    
    .stats {
        grid-template-columns: 1fr;
    }
    
    .result-item {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }
    
    .result-item button {
        width: 100%;
    }
}