:root {
    --primary-color: #007AFF;
    --background-color: #F5F5F7;
    --text-color: #1D1D1F;
    --border-radius: 12px;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    line-height: 1.5;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 2rem;
}

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

header h1 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 0.5rem;
}

header p {
    color: #666;
}

.upload-area {
    background: white;
    border-radius: var(--border-radius);
    padding: 3rem;
    text-align: center;
    border: 2px dashed #ddd;
    transition: all 0.3s ease;
}

.upload-area.drag-over {
    border-color: var(--primary-color);
    background: #f0f8ff;
}

.upload-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
}

.upload-icon {
    width: 48px;
    height: 48px;
    fill: var(--primary-color);
}

.upload-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 20px;
    font-size: 1rem;
    cursor: pointer;
    transition: all 0.3s ease;
}

.upload-btn:hover {
    background: #0056b3;
}

.image-preview {
    margin-top: 2rem;
}

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

.preview-box {
    background: white;
    padding: 1rem;
    border-radius: var(--border-radius);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.preview-box h3 {
    margin-bottom: 1rem;
    color: var(--text-color);
}

.preview-box img {
    max-width: 100%;
    height: auto;
    border-radius: 8px;
}

.image-info {
    margin-top: 1rem;
    color: #666;
}

.controls {
    background: white;
    padding: 1.5rem;
    border-radius: var(--border-radius);
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

.quality-control {
    margin-bottom: 1rem;
}

input[type="range"] {
    width: 100%;
    margin: 0.5rem 0;
}

.download-btn {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 0.8rem 1.5rem;
    border-radius: 20px;
    font-size: 1rem;
    cursor: pointer;
    width: 100%;
    transition: all 0.3s ease;
}

.download-btn:hover {
    background: #0056b3;
}

.hidden {
    display: none;
}

@media (max-width: 768px) {
    .preview-container {
        grid-template-columns: 1fr;
    }
}