body {
    font-family: 'Inter', sans-serif;
    background-color: #f0f2f5;
    display: flex;
    /* This is the key fix: It stacks the header, main, and footer vertically */
    flex-direction: column; 
     /* This ensures the body takes at least the full height of the screen */
    min-height: 100vh;
    margin: 0;
}

/* This makes sure your header and footer can span the full width if they are designed to */
header, footer {
    width: 100%;
}

main.container {
    width: 100%;
    max-width: 100%;
    padding: 20px;
    /* This makes the main content area grow to push the footer to the bottom */
    flex-grow: 1; 
    display: flex;
    justify-content: center;
    align-items: center;
}

.card {
    background-color: #ffffff;
    border-radius: 16px;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.1);
    padding: 40px;
    text-align: center;
    width: 100%;
}

h1 {
    font-size: 2.5rem;
    color: #333;
    margin-bottom: 10px;
}

.seo-text {
    color: #666;
    margin-bottom: 30px;
    line-height: 1.6;
}

.upload-area {
    border: 2px dashed #ccc;
    border-radius: 12px;
    padding: 40px;
    cursor: pointer;
    transition: all 0.3s ease;
}

.upload-area.highlight {
    border-color: #007bff;
    background-color: #f8f9fa;
}

.upload-icon {
    width: 64px;
    height: 64px;
    margin-bottom: 20px;
    opacity: 0.7;
}

.btn {
    background-color: #007bff;
    color: white;
    border: none;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 1rem;
    transition: background-color 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

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

.file-list {
    margin-top: 20px;
    text-align: left;
}

.file-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 10px;
    border: 1px solid #eee;
    border-radius: 8px;
    margin-bottom: 10px;
    background-color: #fafafa;
}

.remove-btn {
    background: none;
    border: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: #999;
}

.options {
    margin-top: 30px;
}

.quality-warning {
    font-size: 0.8rem;
    color: #888;
    margin-top: -15px;
    margin-bottom: 20px;
    background-color: #f8f9fa;
    border: 1px solid #e9ecef;
    padding: 8px;
    border-radius: 6px;
}

.compression-levels {
    display: flex;
    justify-content: center;
    gap: 10px;
    margin-bottom: 20px;
}

.level-btn {
    background-color: #f0f2f5;
    color: #333;
    border: 1px solid #ddd;
    padding: 10px 20px;
}

.level-btn.active {
    background-color: #007bff;
    color: white;
    border-color: #007bff;
}

.compress-btn {
    width: 100%;
    padding: 15px;
    font-size: 1.2rem;
    margin-top: 20px;
}

.compress-btn:disabled {
    background-color: #ccc;
    cursor: not-allowed;
}

.progress-section {
    margin-top: 20px;
    display: none;
}

.progress-bar-container {
    width: 100%;
    background-color: #e9ecef;
    border-radius: 8px;
    overflow: hidden;
    margin-bottom: 10px;
}

.progress-bar {
    width: 0;
    height: 20px;
    background: linear-gradient(90deg, #28a745, #218838);
    border-radius: 8px;
    transition: width 0.4s ease;
}

.download-section {
    margin-top: 20px;
}

.download-item {
    background-color: #f8f9fa;
    padding: 15px;
    border-radius: 8px;
    margin-bottom: 10px;
    border: 1px solid #e9ecef;
}

.hidden {
    display: none;
}

.extra-buttons {
    margin-top: 20px;
    display: flex;
    justify-content: center;
    gap: 10px;
}