/* CSS 变量定义 */
:root {
    --primary-color: #2563eb;
    --secondary-color: #64748b;
    --success-color: #10b981;
    --danger-color: #ef4444;
    --warning-color: #f59e0b;
    
    --bg-primary: #ffffff;
    --bg-secondary: #f8fafc;
    --bg-tertiary: #f1f5f9;
    
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-muted: #94a3b8;
    
    --border-color: #e2e8f0;
    --border-radius: 8px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
    
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, monospace;
}

/* 基础重置 */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: var(--font-family);
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.6;
    height: 100vh;
    display: flex;
    flex-direction: column;
}

/* 头部样式 */
.header {
    background: var(--bg-primary);
    border-bottom: 1px solid var(--border-color);
    padding: 1rem 0;
    box-shadow: var(--shadow-sm);
}

.header-content {
    max-width: 1400px;
    margin: 0 auto;
    padding: 0 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    font-size: 1.5rem;
    font-weight: 600;
    color: var(--primary-color);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.header-controls {
    display: flex;
    gap: 0.5rem;
}

/* 按钮样式 */
.btn {
    padding: 0.5rem 1rem;
    border: none;
    border-radius: var(--border-radius);
    font-size: 0.875rem;
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s;
    display: inline-flex;
    align-items: center;
    gap: 0.5rem;
    text-decoration: none;
}

.btn:hover {
    transform: translateY(-1px);
    box-shadow: var(--shadow-md);
}

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

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

.btn-danger {
    background: var(--danger-color);
    color: white;
}

.btn-sm {
    padding: 0.25rem 0.5rem;
    font-size: 0.75rem;
}

/* 主容器 */
.main-container {
    flex: 1;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 1px;
    background: var(--border-color);
    overflow: hidden;
}

/* 编辑器区域 */
.editor-section {
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
}

.section-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: var(--bg-secondary);
}

.section-header h2 {
    font-size: 1.125rem;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 0.5rem;
    color: var(--text-primary);
}

.format-selector {
    display: flex;
    gap: 1rem;
}

.format-selector label {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    cursor: pointer;
    font-size: 0.875rem;
}

.format-selector input[type="radio"] {
    margin: 0;
}

.editor-container {
    flex: 1;
    padding: 1rem;
}

#editor {
    width: 100%;
    height: 100%;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    padding: 1rem;
    font-family: var(--font-mono);
    font-size: 0.875rem;
    line-height: 1.5;
    resize: none;
    outline: none;
    background: var(--bg-primary);
    color: var(--text-primary);
    overflow: auto;
}

#editor:focus {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgb(37 99 235 / 0.1);
}

/* 预览区域 */
.preview-section {
    background: var(--bg-primary);
    display: flex;
    flex-direction: column;
}

.preview-controls {
    display: flex;
    gap: 0.5rem;
}

.preview-container {
    flex: 1;
    padding: 1rem;
    overflow: auto;
}

.preview-content {
    max-width: none;
    line-height: 1.7;
}

.html-preview {
    width: 100%;
    height: 100%;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: white;
}

/* Markdown 样式 */
.preview-content h1,
.preview-content h2,
.preview-content h3,
.preview-content h4,
.preview-content h5,
.preview-content h6 {
    margin: 1.5rem 0 1rem 0;
    font-weight: 600;
    line-height: 1.3;
}

.preview-content h1 { font-size: 2rem; color: var(--text-primary); }
.preview-content h2 { font-size: 1.5rem; color: var(--text-primary); }
.preview-content h3 { font-size: 1.25rem; color: var(--text-primary); }

.preview-content p {
    margin: 1rem 0;
}

.preview-content ul,
.preview-content ol {
    margin: 1rem 0;
    padding-left: 2rem;
}

.preview-content li {
    margin: 0.5rem 0;
}

.preview-content blockquote {
    margin: 1rem 0;
    padding: 1rem;
    background: var(--bg-secondary);
    border-left: 4px solid var(--primary-color);
    border-radius: 0 var(--border-radius) var(--border-radius) 0;
}

.preview-content code {
    background: var(--bg-tertiary);
    padding: 0.125rem 0.25rem;
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.875em;
}

.preview-content pre {
    margin: 1rem 0;
    padding: 1rem;
    background: #2d3748;
    border-radius: var(--border-radius);
    overflow-x: auto;
}

.preview-content pre code {
    background: none;
    padding: 0;
    color: #e2e8f0;
}

.preview-content table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}

.preview-content th,
.preview-content td {
    padding: 0.75rem;
    text-align: left;
    border-bottom: 1px solid var(--border-color);
}

.preview-content th {
    background: var(--bg-secondary);
    font-weight: 600;
}

.preview-content a {
    color: var(--primary-color);
    text-decoration: none;
}

.preview-content a:hover {
    text-decoration: underline;
}

.preview-content hr {
    margin: 2rem 0;
    border: none;
    border-top: 1px solid var(--border-color);
}

/* 状态栏 */
.status-bar {
    background: var(--bg-secondary);
    border-top: 1px solid var(--border-color);
    padding: 0.5rem 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 0.875rem;
    color: var(--text-secondary);
}

.status-info {
    display: flex;
    gap: 1rem;
}

/* 模态框 */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1000;
}

.modal-content {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    background: var(--bg-primary);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    width: 90%;
    height: 90%;
    max-width: 1200px;
    display: flex;
    flex-direction: column;
}

.modal-header {
    padding: 1rem;
    border-bottom: 1px solid var(--border-color);
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.modal-body {
    flex: 1;
    padding: 1rem;
    overflow: auto;
}

.modal-body iframe {
    width: 100%;
    height: 100%;
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius);
    background: white;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .main-container {
        grid-template-columns: 1fr;
        grid-template-rows: 1fr 1fr;
    }
    
    .header-content {
        flex-direction: column;
        gap: 1rem;
    }
    
    .section-header {
        flex-direction: column;
        gap: 0.5rem;
        align-items: flex-start;
    }
    
    .status-info {
        flex-direction: column;
        gap: 0.25rem;
    }
}