/* Reset và 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;
}

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

/* Header */
.header {
    text-align: center;
    color: white;
    margin-bottom: 40px;
}

.header h1 {
    font-size: 2.5rem;
    margin-bottom: 10px;
    text-shadow: 2px 2px 4px rgba(0,0,0,0.3);
}

.header h1 i {
    margin-right: 15px;
    color: #ffd700;
}

.header p {
    font-size: 1.1rem;
    opacity: 0.9;
}

/* Main Content */
.main-content {
    background: white;
    border-radius: 20px;
    padding: 40px;
    box-shadow: 0 20px 40px rgba(0,0,0,0.1);
    margin-bottom: 30px;
}

/* Upload Section */
.upload-section {
    margin-bottom: 40px;
}

.upload-area {
    border: 3px dashed #ddd;
    border-radius: 15px;
    padding: 60px 20px;
    text-align: center;
    background: #fafafa;
    transition: all 0.3s ease;
    cursor: pointer;
    position: relative;
    overflow: hidden;
}

.upload-area:hover {
    border-color: #667eea;
    background: #f0f4ff;
    transform: translateY(-2px);
}

.upload-area.dragover {
    border-color: #667eea;
    background: #e8f2ff;
    transform: scale(1.02);
}

.upload-area i {
    font-size: 4rem;
    color: #667eea;
    margin-bottom: 20px;
    display: block;
}

.upload-area h3 {
    font-size: 1.5rem;
    margin-bottom: 10px;
    color: #333;
}

.upload-area p {
    color: #666;
    font-size: 1.1rem;
}

.upload-link {
    color: #667eea;
    font-weight: bold;
    text-decoration: underline;
    cursor: pointer;
}

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

/* Settings Section */
.settings-section {
    background: #f8f9fa;
    border-radius: 15px;
    padding: 30px;
    margin-bottom: 30px;
}

.settings-section h3 {
    margin-bottom: 25px;
    color: #333;
    font-size: 1.3rem;
}

.settings-section h3 i {
    margin-right: 10px;
    color: #667eea;
}

.settings-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.setting-item {
    display: flex;
    flex-direction: column;
}

.setting-item label {
    font-weight: 600;
    margin-bottom: 8px;
    color: #555;
}

.setting-item input,
.setting-item select {
    padding: 12px;
    border: 2px solid #ddd;
    border-radius: 8px;
    font-size: 1rem;
    transition: border-color 0.3s ease;
}

.setting-item input:focus,
.setting-item select:focus {
    outline: none;
    border-color: #667eea;
}

.setting-item input[type="range"] {
    padding: 0;
    height: 8px;
    background: #ddd;
    border-radius: 5px;
    -webkit-appearance: none;
}

.setting-item input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none;
    width: 20px;
    height: 20px;
    background: #667eea;
    border-radius: 50%;
    cursor: pointer;
}

.setting-item input[type="range"]::-moz-range-thumb {
    width: 20px;
    height: 20px;
    background: #667eea;
    border-radius: 50%;
    cursor: pointer;
    border: none;
}

.setting-item small {
    display: block;
    margin-top: 5px;
    font-style: italic;
}

#qualityValue {
    font-weight: bold;
    color: #667eea;
    margin-left: 10px;
}

/* Buttons */
.btn {
    padding: 15px 30px;
    border: none;
    border-radius: 10px;
    font-size: 1.1rem;
    font-weight: 600;
    cursor: pointer;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(102, 126, 234, 0.6);
}

.btn-download {
    background: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(76, 175, 80, 0.4);
    font-size: 0.9rem;
    padding: 10px 20px;
}

.btn-download:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(76, 175, 80, 0.6);
}

/* Results Section */
.results-section {
    margin-top: 30px;
}

.results-section h3 {
    margin-bottom: 25px;
    color: #333;
    font-size: 1.3rem;
}

.results-section h3 i {
    margin-right: 10px;
    color: #667eea;
}

.results-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 25px;
}

.result-item {
    background: #f8f9fa;
    border-radius: 15px;
    padding: 25px;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.result-item:hover {
    transform: translateY(-5px);
}

.result-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
}

.result-title {
    font-weight: 600;
    color: #333;
    font-size: 1.1rem;
}

.compression-badge {
    background: linear-gradient(135deg, #4CAF50 0%, #45a049 100%);
    color: white;
    padding: 5px 12px;
    border-radius: 20px;
    font-size: 0.8rem;
    font-weight: 600;
}

.image-preview {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 20px;
}

.preview-item {
    text-align: center;
}

.preview-item img {
    max-width: 100%;
    height: 150px;
    object-fit: cover;
    border-radius: 10px;
    box-shadow: 0 3px 10px rgba(0,0,0,0.2);
}

.preview-label {
    font-size: 0.9rem;
    color: #666;
    margin-top: 8px;
    font-weight: 500;
}

.image-stats {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 15px;
    margin-bottom: 20px;
}

.stat-item {
    text-align: center;
    padding: 15px;
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
}

.stat-value {
    font-size: 1.2rem;
    font-weight: bold;
    color: #333;
    margin-bottom: 5px;
}

.stat-label {
    font-size: 0.8rem;
    color: white;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.compression-info {
    background: linear-gradient(135deg, #e3f2fd 0%, #bbdefb 100%);
    border-radius: 10px;
    padding: 15px;
    text-align: center;
    margin-bottom: 20px;
}

.compression-ratio {
    font-size: 1.5rem;
    font-weight: bold;
    color: #1976d2;
    margin-bottom: 5px;
}

.compression-text {
    font-size: 0.9rem;
    color: #555;
}

/* Loading */
.loading {
    text-align: center;
    padding: 40px;
}

.spinner {
    width: 50px;
    height: 50px;
    border: 5px solid #f3f3f3;
    border-top: 5px solid #667eea;
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin: 0 auto 20px;
}

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

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

/* Footer */
.footer {
    text-align: center;
    color: white;
    opacity: 0.8;
    font-size: 0.9rem;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 10px;
    }
    
    .main-content {
        padding: 20px;
    }
    
    .header h1 {
        font-size: 2rem;
    }
    
    .upload-area {
        padding: 40px 20px;
    }
    
    .upload-area i {
        font-size: 3rem;
    }
    
    .settings-grid {
        grid-template-columns: 1fr;
    }
    
    .image-preview {
        grid-template-columns: 1fr;
    }
    
    .image-stats {
        grid-template-columns: 1fr;
    }
    
    .results-grid {
        grid-template-columns: 1fr;
    }
}

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

.result-item {
    animation: fadeInUp 0.6s ease-out;
}

/* Success animation */
@keyframes successPulse {
    0% { transform: scale(1); }
    50% { transform: scale(1.05); }
    100% { transform: scale(1); }
}

.compression-badge {
    animation: successPulse 0.6s ease-out;
}