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

:root {
    --primary-color: #1677ff;
    --primary-hover: #4096ff;
    --success-color: #52c41a;
    --border-color: #d9d9d9;
    --bg-color: #f5f5f5;
    --text-color: #333;
    --text-secondary: #666;
    --text-hint: #999;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, 'PingFang SC', 'Microsoft YaHei', sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    line-height: 1.6;
    min-height: 100vh;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 40px 20px;
}

header {
    text-align: center;
    margin-bottom: 40px;
}

header h1 {
    font-size: 28px;
    font-weight: 600;
    color: var(--text-color);
    margin-bottom: 10px;
}

.subtitle {
    color: var(--primary-color);
    font-size: 14px;
}

/* 步骤指示器 */
.steps {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 40px;
}

.step {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.step-number {
    width: 32px;
    height: 32px;
    border-radius: 50%;
    background: var(--border-color);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 14px;
    font-weight: 500;
}

.step.active .step-number,
.step.completed .step-number {
    background: var(--primary-color);
}

.step-text {
    font-size: 14px;
    color: var(--text-hint);
}

.step.active .step-text {
    color: var(--primary-color);
    font-weight: 500;
}

.step.completed .step-text {
    color: var(--text-color);
}

.step-line {
    width: 100px;
    height: 1px;
    background: var(--border-color);
    margin: 0 20px;
    margin-bottom: 24px;
}

/* 面板 */
.panel {
    background: #fff;
    border-radius: 8px;
    padding: 30px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
}

/* 上传区域 */
.upload-area {
    border: 2px dashed var(--border-color);
    border-radius: 8px;
    padding: 60px 20px;
    text-align: center;
    cursor: pointer;
    transition: all 0.3s;
}

.upload-area:hover,
.upload-area.dragover {
    border-color: var(--primary-color);
    background: rgba(22, 119, 255, 0.02);
}

.upload-icon {
    color: var(--text-hint);
    margin-bottom: 16px;
}

.upload-text {
    font-size: 16px;
    color: var(--text-secondary);
    margin-bottom: 8px;
}

.upload-hint {
    font-size: 13px;
    color: var(--text-hint);
}

/* 文件列表 */
.file-list {
    margin-top: 24px;
}

.file-list-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 16px;
}

.file-list-header h3 {
    font-size: 16px;
    font-weight: 500;
}

.file-items {
    display: flex;
    flex-direction: column;
    gap: 8px;
    max-height: 300px;
    overflow-y: auto;
}

.file-item {
    display: flex;
    align-items: center;
    padding: 12px 16px;
    background: var(--bg-color);
    border-radius: 6px;
    gap: 12px;
}

.file-item-icon {
    width: 40px;
    height: 40px;
    background: #fff;
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
    color: var(--primary-color);
}

.file-item-info {
    flex: 1;
    min-width: 0;
}

.file-item-name {
    font-size: 14px;
    color: var(--text-color);
    white-space: nowrap;
    overflow: hidden;
    text-overflow: ellipsis;
}

.file-item-size {
    font-size: 12px;
    color: var(--text-hint);
}

.file-item-remove {
    width: 24px;
    height: 24px;
    border: none;
    background: transparent;
    cursor: pointer;
    color: var(--text-hint);
    border-radius: 4px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.file-item-remove:hover {
    background: rgba(0, 0, 0, 0.05);
    color: #ff4d4f;
}

/* 按钮 */
.btn {
    padding: 10px 24px;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.3s;
    border: none;
}

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

.btn-primary:hover:not(:disabled) {
    background: var(--primary-hover);
}

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

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

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

.btn-text {
    background: transparent;
    color: var(--primary-color);
    padding: 4px 8px;
}

.btn-text:hover {
    background: rgba(22, 119, 255, 0.05);
}

.btn-lg {
    padding: 14px 40px;
    font-size: 16px;
}

.panel-actions {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-top: 30px;
    padding-top: 24px;
    border-top: 1px solid var(--bg-color);
}

/* 设置面板 */
.settings-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 30px;
}

.setting-group {
    padding: 20px;
    background: var(--bg-color);
    border-radius: 8px;
}

.setting-group h3 {
    font-size: 15px;
    font-weight: 500;
    margin-bottom: 20px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--border-color);
}

.setting-item {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 16px;
}

.setting-item:last-child {
    margin-bottom: 0;
}

.setting-item > label:first-child {
    font-size: 14px;
    color: var(--text-secondary);
}

.radio-group {
    display: flex;
    gap: 20px;
}

.radio-label,
.checkbox-label {
    display: flex;
    align-items: center;
    gap: 8px;
    cursor: pointer;
    font-size: 14px;
}

.checkbox-label {
    justify-content: flex-start;
    width: 100%;
}

.input-number {
    width: 80px;
    padding: 6px 12px;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    font-size: 14px;
    text-align: center;
}

.input-number:focus {
    outline: none;
    border-color: var(--primary-color);
}

/* 预览区域 */
.preview-group {
    grid-column: 1 / -1;
}

.preview-wrapper {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.preview-nav {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
}

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

.btn-small {
    padding: 6px 12px;
    font-size: 12px;
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 4px;
    cursor: pointer;
}

.btn-small:hover:not(:disabled) {
    border-color: var(--primary-color);
    color: var(--primary-color);
}

.btn-small:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.preview-container {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 20px;
    background: #e8e8e8;
    border-radius: 6px;
    min-height: 400px;
    position: relative;
}

#preview-canvas {
    max-width: 100%;
    max-height: 500px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.15);
    background: #fff;
}

.preview-loading {
    position: absolute;
    display: flex;
    align-items: center;
    gap: 8px;
    color: var(--text-secondary);
    font-size: 14px;
}

.spinner-small {
    width: 20px;
    height: 20px;
    border: 2px solid var(--bg-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

.preview-info {
    text-align: center;
    margin-top: 16px;
    font-size: 14px;
    color: var(--text-secondary);
}

.preview-info span {
    color: var(--primary-color);
    font-weight: 500;
}

/* 结果区域 */
.result-area {
    text-align: center;
    padding: 40px 20px;
}

.processing {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

.spinner {
    width: 48px;
    height: 48px;
    border: 3px solid var(--bg-color);
    border-top-color: var(--primary-color);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    to {
        transform: rotate(360deg);
    }
}

.progress-bar {
    width: 300px;
    height: 8px;
    background: var(--bg-color);
    border-radius: 4px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    background: var(--primary-color);
    width: 0%;
    transition: width 0.3s;
}

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

.result-success {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 16px;
}

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

.result-success h3 {
    font-size: 20px;
    font-weight: 500;
}

.result-info {
    color: var(--text-secondary);
    margin-bottom: 16px;
}

/* 页脚 */
footer {
    text-align: center;
    padding: 30px;
    color: var(--text-hint);
    font-size: 13px;
}

/* 响应式 */
@media (max-width: 768px) {
    .container {
        padding: 20px 16px;
    }

    .steps {
        flex-wrap: wrap;
        gap: 10px;
    }

    .step-line {
        display: none;
    }

    .settings-grid {
        grid-template-columns: 1fr;
    }

    .preview-container {
        overflow-x: auto;
    }
}