/* ===== 基础样式重置 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* ===== 根变量定义 ===== */
:root {
    /* 主色调 - 科技感紫蓝色系 */
    --primary-color: #6366f1;
    --primary-hover: #4f46e5;
    --primary-light: #8b5cf6;
    
    /* 辅助色调 */
    --secondary-color: #64748b;
    --accent-color: #06b6d4;
    --success-color: #10b981;
    --warning-color: #f59e0b;
    --error-color: #ef4444;
    --info-color: #3b82f6;
    
    /* 中性色调 */
    --gray-50: #0f172a;
    --gray-100: #1e293b;
    --gray-200: #334155;
    --gray-300: #475569;
    --gray-400: #64748b;
    --gray-500: #94a3b8;
    --gray-600: #cbd5e1;
    --gray-700: #e2e8f0;
    --gray-800: #f1f5f9;
    --gray-900: #f8fafc;
    
    /* 背景色 - 深色主题 */
    --bg-primary: #0f172a;
    --bg-secondary: #1e293b;
    --bg-tertiary: #334155;
    
    /* 文字颜色 - 深色主题 */
    --text-primary: #f8fafc;
    --text-secondary: #cbd5e1;
    --text-muted: #94a3b8;
    
    /* 边框和阴影 */
    --border-color: #334155;
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1), 0 4px 6px -4px rgb(0 0 0 / 0.1);
    
    /* 字体 */
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', 'Roboto Mono', Consolas, 'Courier New', monospace;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    
    /* 过渡动画 */
    --transition-fast: 0.15s ease-in-out;
    --transition-normal: 0.3s ease-in-out;
    --transition-slow: 0.5s ease-in-out;
}

/* ===== 基础元素样式 ===== */
body {
    font-family: var(--font-family);
    line-height: 1.6;
    color: var(--text-primary);
    background: linear-gradient(135deg, #0f172a 0%, #1e293b 50%, #334155 100%);
    background-attachment: fixed;
    font-size: 16px;
    min-height: 100vh;
}

/* 容器布局 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ===== 顶部导航栏 ===== */
.header {
    background: linear-gradient(135deg, #1e1b4b 0%, #312e81 25%, #4c1d95 50%, #6366f1 75%, #8b5cf6 100%);
    color: white;
    padding: var(--spacing-md) 0;
    box-shadow: 0 8px 32px rgba(99, 102, 241, 0.3);
    text-align: center;
    position: relative;
    overflow: hidden;
    border-bottom: 1px solid rgba(99, 102, 241, 0.2);
}

.header::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(255, 255, 255, 0.1), transparent);
    animation: shimmer 3s infinite;
}

@keyframes shimmer {
    0% { left: -100%; }
    100% { left: 100%; }
}

.logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
}

.logo i,
.logo span {
    font-size: 1.6rem;
    color: var(--accent-color);
    animation: pulse 2s infinite;
    display: inline-block;
}

@keyframes pulse {
    0%, 100% { transform: scale(1); }
    50% { transform: scale(1.1); }
}

.logo h1 {
    font-size: 2.6rem;
    font-weight: 800;
    font-family: 'Arial Black', 'Microsoft YaHei', '微软雅黑', sans-serif;
    letter-spacing: -0.025em;
    background: linear-gradient(45deg, #ffffff 0%, #06b6d4 25%, #8b5cf6 50%, #6366f1 75%, #ffffff 100%);
    background-size: 200% 200%;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    animation: gradientShift 3s ease-in-out infinite;
}

@keyframes gradientShift {
    0%, 100% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
}

.tagline {
    font-size: 1.125rem;
    opacity: 0.9;
    font-weight: 300;
    text-align: center;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    animation: fadeInUp 1s ease-out;
}

@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 0.9;
        transform: translateY(0);
    }
}

/* ===== 主要内容区域 ===== */
.main {
    padding: var(--spacing-2xl) 0;
    min-height: calc(100vh - 200px);
}

/* ===== 功能选择区 ===== */
.function-selector {
    margin-bottom: var(--spacing-2xl);
}

.function-selector h2 {
    text-align: center;
    font-size: 1.875rem;
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--spacing-xl);
}

/* 两行入口：第一行“其他→Markdown”，第二行“Markdown→其他” */
.function-rows {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
    max-width: 1000px;
    margin: 0 auto;
}

.function-row {
    display: grid;
    grid-template-columns: repeat(5, minmax(0, 1fr));
    gap: var(--spacing-md);
}

.function-card {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-md);
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    overflow: hidden;
    min-height: 84px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
}

.function-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg, transparent, rgba(99, 102, 241, 0.2), transparent);
    transition: left var(--transition-slow);
}

.function-card:hover::before {
    left: 100%;
}

.function-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 32px rgba(99, 102, 241, 0.4), 0 0 20px rgba(99, 102, 241, 0.2);
    border-color: var(--primary-color);
    background: linear-gradient(135deg, var(--bg-secondary) 0%, var(--bg-tertiary) 100%);
}

.function-card.active {
    border-color: var(--primary-color);
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
    color: white;
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

.card-icon {
    font-size: 2rem;
    margin-bottom: var(--spacing-xs);
    color: var(--primary-color);
    transition: all var(--transition-normal);
    display: block;
}

.function-card.active .card-icon {
    color: white;
    transform: scale(1.1);
}

.function-card h3 {
    font-size: 0.95rem;
    font-weight: 600;
    margin: 0;
    text-align: center;
}

.function-card p {
    display: none;
}

/* ===== 转换工作区 ===== */
.converter-workspace {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    margin: var(--spacing-xl) auto var(--spacing-xl) auto;
    max-width: 1000px;
}

.workspace-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-xl);
    margin-bottom: var(--spacing-xl);
}

.section-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: var(--spacing-md);
    padding-bottom: var(--spacing-sm);
    border-bottom: 2px solid var(--border-color);
}

.section-header h3 {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.125rem;
    font-weight: 600;
    color: var(--text-primary);
}

.section-header i {
    color: var(--primary-color);
}

.section-actions {
    display: flex;
    gap: var(--spacing-sm);
}

/* ===== 输入输出区域 ===== */
.input-container,
.output-container {
    position: relative;
}

#input-text {
    width: 100%;
    min-height: 400px;
    height: 400px;
    max-height: 600px;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-family: 'Microsoft YaHei', '微软雅黑', sans-serif;
    font-size: 0.875rem;
    line-height: 1.6;
    resize: vertical;
    transition: border-color var(--transition-fast);
    background: #2a2a3e;
    color: #e2e8f0;
    overflow-y: auto;
}

#input-text:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.3);
}

#input-text::placeholder {
    color: #94a3b8;
    opacity: 1;
}

.output-display {
    min-height: 400px;
    height: 400px;
    max-height: 600px;
    padding: var(--spacing-md);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    background: #2a2a3e;
    font-family: 'Microsoft YaHei', '微软雅黑', sans-serif;
    font-size: 0.875rem;
    line-height: 1.6;
    white-space: pre-wrap;
    overflow-y: auto;
    color: #e2e8f0;
}

/* ===== 按钮样式 ===== */
.btn-primary,
.btn-secondary {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    padding: var(--spacing-sm) var(--spacing-md);
    border: none;
    border-radius: var(--border-radius);
    font-weight: 500;
    font-size: 0.875rem;
    cursor: pointer;
    transition: all var(--transition-fast);
    text-decoration: none;
    position: relative;
    overflow: hidden;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary-color) 0%, var(--primary-light) 100%);
    color: white;
    padding: var(--spacing-md) var(--spacing-xl);
    font-size: 1rem;
    font-weight: 600;
    box-shadow: var(--shadow-md);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: linear-gradient(135deg, var(--primary-hover) 0%, var(--primary-color) 100%);
}

.btn-primary:active {
    transform: translateY(0);
}

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

.btn-secondary:hover {
    background: var(--gray-200);
    color: var(--text-primary);
    border-color: var(--gray-300);
    transform: translateY(-1px);
}

/* ===== 转换按钮区域 ===== */
.convert-action {
    text-align: center;
}

/* ===== 预览区域 ===== */
.preview-section {
    background: linear-gradient(135deg, var(--bg-primary) 0%, var(--bg-secondary) 100%);
    border: 1px solid var(--border-color);
    border-radius: var(--border-radius-lg);
    padding: var(--spacing-xl);
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.4);
    margin: var(--spacing-xl) auto;
    max-width: 1000px;
    animation: slideIn var(--transition-normal) ease-out;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.preview-display {
    min-height: 300px;
    padding: var(--spacing-xl) var(--spacing-2xl);
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    background: var(--bg-primary);
    overflow-y: auto;
}

.preview-display h1,
.preview-display h2,
.preview-display h3,
.preview-display h4,
.preview-display h5,
.preview-display h6 {
    margin-top: var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    color: var(--text-primary);
}

.preview-display p {
    margin-bottom: var(--spacing-md);
    color: var(--text-secondary);
}

.preview-display a {
    color: var(--primary-color);
    text-decoration: underline;
    text-underline-offset: 3px;
}

.preview-display a:hover {
    color: var(--secondary-color);
}

.preview-display ul,
.preview-display ol {
    margin: 0 0 var(--spacing-md) 1.25rem;
    padding: 0;
    color: var(--text-secondary);
}

.preview-display li {
    margin: var(--spacing-xs) 0;
    line-height: 1.7;
}

.preview-display img {
    max-width: 100%;
    height: auto;
    border-radius: var(--border-radius);
    display: block;
    margin: var(--spacing-md) 0;
}

.preview-display hr {
    border: 0;
    height: 1px;
    background: var(--border-color);
    margin: var(--spacing-lg) 0;
}

.preview-display code {
    background: var(--bg-tertiary);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 4px;
    font-family: var(--font-mono);
    font-size: 0.875rem;
}

.preview-display pre {
    background: var(--bg-tertiary);
    padding: var(--spacing-md);
    border-radius: var(--border-radius);
    overflow-x: auto;
    margin: var(--spacing-md) 0;
}

.preview-display pre code {
    background: transparent;
    padding: 0;
    font-size: 0.875rem;
    color: var(--text-primary);
    display: block;
}

.preview-display blockquote {
    border-left: 4px solid var(--primary-color);
    padding-left: var(--spacing-md);
    margin: var(--spacing-md) 0;
    color: var(--text-muted);
    font-style: italic;
}

.preview-display table {
    width: 100%;
    border-collapse: collapse;
    margin: var(--spacing-md) 0;
}

.preview-display th,
.preview-display td {
    border: 1px solid var(--border-color);
    padding: var(--spacing-sm);
    text-align: left;
}

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

/* ===== 底部信息 ===== */
.footer {
    background: var(--gray-800);
    color: var(--gray-300);
    padding: var(--spacing-xl) 0;
}

.footer-content {
    text-align: center;
}

.footer-info {
    color: var(--gray-400);
    font-size: 0.875rem;
}

.footer a {
    color: inherit;
    text-decoration: none;
}

.footer a:visited {
    color: inherit;
}

.footer a:hover,
.footer a:active,
.footer a:focus {
    color: inherit;
    text-decoration: none;
}

/* ===== 提示消息 ===== */
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    background: var(--success-color);
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-lg);
    transform: translateX(400px);
    transition: transform var(--transition-normal);
    z-index: 1000;
    font-weight: 500;
}

.toast.show {
    transform: translateX(0);
}

.toast.error {
    background: var(--error-color);
}

.toast.warning {
    background: var(--warning-color);
}

.toast.info {
    background: var(--info-color);
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .function-row {
        grid-template-columns: repeat(3, minmax(0, 1fr));
    }
}

@media (max-width: 768px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .logo h1 {
        font-size: 2rem;
    }
    
    .tagline {
        font-size: 1rem;
    }
    
    .function-row {
        grid-template-columns: repeat(2, minmax(0, 1fr));
    }
    
    .workspace-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: var(--spacing-sm);
    }
    
    .section-actions {
        width: 100%;
        justify-content: flex-end;
    }
    
    #input-text,
    .output-display {
        min-height: 300px;
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        gap: var(--spacing-md);
    }
    
    .footer-info {
        text-align: left;
    }
    
    .toast {
        right: var(--spacing-sm);
        left: var(--spacing-sm);
        transform: translateY(-100px);
    }
    
    .toast.show {
        transform: translateY(0);
    }
}

@media (max-width: 480px) {
    .function-row {
        grid-template-columns: 1fr;
    }

    .main {
        padding: var(--spacing-lg) 0;
    }
    
    .converter-workspace,
    .preview-section {
        padding: var(--spacing-md);
    }
    
    .function-card {
        padding: var(--spacing-md);
    }
    
    .card-icon {
        font-size: 2rem;
    }
    
    .btn-secondary {
        padding: var(--spacing-xs) var(--spacing-sm);
        font-size: 0.75rem;
    }
}

/* ===== 滚动条样式 ===== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--bg-tertiary);
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: var(--gray-400);
    border-radius: 4px;
    transition: background var(--transition-fast);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--gray-500);
}

/* ===== 选择文本样式 ===== */
::selection {
    background: rgba(37, 99, 235, 0.2);
    color: var(--text-primary);
}

/* ===== 焦点样式 ===== */
*:focus {
    outline: 2px solid var(--primary-color);
    outline-offset: 2px;
}

button:focus,
input:focus,
textarea:focus {
    outline: none;
}

/* ===== 加载动画 ===== */
@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.loading {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}