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

:root {
    --bg-color: #f5f5f5;
    --card-bg: #ffffff;
    --text-primary: #333333;
    --text-secondary: #666666;
    --border-color: #e0e0e0;
    --accent-color: #555555;
    --accent-hover: #444444;
    --success-color: #4a9c6d;
    --error-color: #c75450;
    --radius: 8px;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Oxygen, Ubuntu, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 480px;
}

.card {
    background: var(--card-bg);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 32px;
}

h1 {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 8px;
    text-align: center;
}

h2 {
    font-size: 20px;
    font-weight: 600;
    margin-bottom: 8px;
}

.subtitle {
    color: var(--text-secondary);
    text-align: center;
    margin-bottom: 24px;
    font-size: 14px;
}

.file-drop-area {
    border: 2px dashed var(--border-color);
    border-radius: var(--radius);
    padding: 32px;
    text-align: center;
    cursor: pointer;
    transition: border-color 0.2s, background-color 0.2s;
    margin-bottom: 16px;
}

.file-drop-area:hover {
    border-color: var(--accent-color);
    background-color: #fafafa;
}

.file-drop-area.dragover {
    border-color: var(--accent-color);
    background-color: #f0f0f0;
}

.file-input {
    display: none;
}

.file-label {
    display: block;
    cursor: pointer;
    color: var(--text-secondary);
}

.file-label svg {
    width: 48px;
    height: 48px;
    margin-bottom: 12px;
    color: var(--border-color);
}

.file-name {
    margin-top: 12px;
    font-weight: 500;
    color: var(--text-primary);
    word-break: break-all;
}

.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    width: 100%;
    padding: 12px 24px;
    font-size: 15px;
    font-weight: 500;
    color: #fff;
    background-color: var(--accent-color);
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn:hover {
    background-color: var(--accent-hover);
}

.btn:disabled {
    background-color: var(--border-color);
    cursor: not-allowed;
}

.btn-secondary {
    background-color: transparent;
    color: var(--text-primary);
    border: 1px solid var(--border-color);
}

.btn-secondary:hover {
    background-color: #f5f5f5;
}

.progress-container {
    margin-top: 16px;
    display: none;
}

.progress-container.visible {
    display: block;
}

.progress-bar {
    height: 6px;
    background-color: var(--border-color);
    border-radius: 3px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background-color: var(--success-color);
    width: 0%;
    transition: width 0.2s;
}

.progress-text {
    margin-top: 8px;
    font-size: 13px;
    color: var(--text-secondary);
    text-align: center;
}

.error-message {
    margin-top: 16px;
    padding: 12px;
    background-color: #fdf2f2;
    border: 1px solid var(--error-color);
    border-radius: var(--radius);
    color: var(--error-color);
    font-size: 14px;
    display: none;
}

.error-message.visible {
    display: block;
}

.file-info {
    margin-bottom: 24px;
}

.file-info-item {
    display: flex;
    justify-content: space-between;
    padding: 12px 0;
    border-bottom: 1px solid var(--border-color);
}

.file-info-item:last-child {
    border-bottom: none;
}

.file-info-label {
    color: var(--text-secondary);
    font-size: 14px;
}

.file-info-value {
    font-weight: 500;
    font-size: 14px;
    word-break: break-all;
    text-align: right;
    max-width: 60%;
}

.url-container {
    display: flex;
    gap: 8px;
    margin-top: 24px;
}

.url-input {
    flex: 1;
    padding: 10px 12px;
    font-size: 14px;
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    background-color: #fafafa;
    color: var(--text-secondary);
    font-family: monospace;
}

.url-input:focus {
    outline: none;
    border-color: var(--accent-color);
}

.btn-copy {
    padding: 10px 16px;
    font-size: 14px;
    white-space: nowrap;
}

.btn-download {
    margin-top: 24px;
}

.file-status {
    display: inline-block;
    padding: 4px 10px;
    border-radius: 4px;
    font-size: 12px;
    font-weight: 500;
}

.file-status.active {
    background-color: #e8f5e9;
    color: var(--success-color);
}

.file-status.expired,
.file-status.consumed {
    background-color: #fdf2f2;
    color: var(--error-color);
}

.footer {
    margin-top: 24px;
    text-align: center;
}

.footer a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: 14px;
}

.footer a:hover {
    text-decoration: underline;
}