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

:root {
    /* Apple风格配色系统 */
    --primary-color: #007AFF;
    --primary-hover: #0056CC;
    --secondary-color: #5856D6;
    --accent-color: #FF3B30;
    --success-color: #30D158;
    --warning-color: #FF9F0A;
    
    /* 现代背景系统 */
    --background-primary: #FFFFFF;
    --background-secondary: #F2F2F7;
    --background-tertiary: #FFFFFF;
    --surface-primary: #FFFFFF;
    --surface-secondary: rgba(255, 255, 255, 0.8);
    --surface-elevated: #FFFFFF;
    
    /* 苹果风格文字颜色 */
    --text-primary: #1D1D1F;
    --text-secondary: #86868B;
    --text-tertiary: #C7C7CC;
    --text-inverse: #FFFFFF;
    
    /* 现代边框系统 */
    --border-primary: rgba(0, 0, 0, 0.1);
    --border-secondary: rgba(0, 0, 0, 0.05);
    --separator: rgba(60, 60, 67, 0.29);
    
    /* 苹果风格阴影 */
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.05), 0 2px 4px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1), 0 4px 6px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px rgba(0, 0, 0, 0.1), 0 10px 10px rgba(0, 0, 0, 0.04);
    
    /* 现代圆角系统 */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-xl: 20px;
    --radius-2xl: 24px;
    --radius-full: 50%;
    
    /* 苹果字体系统 */
    --font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Display', 'SF Pro Text', system-ui, sans-serif;
    --font-mono: 'SF Mono', Monaco, 'Cascadia Code', monospace;
    
    /* 现代字体大小 */
    --text-xs: 0.75rem;    /* 12px */
    --text-sm: 0.875rem;   /* 14px */
    --text-base: 1rem;     /* 16px */
    --text-lg: 1.125rem;   /* 18px */
    --text-xl: 1.25rem;    /* 20px */
    --text-2xl: 1.5rem;    /* 24px */
    --text-3xl: 1.875rem;  /* 30px */
    --text-4xl: 2.25rem;   /* 36px */
    --text-5xl: 3rem;      /* 48px */
    --text-6xl: 3.75rem;   /* 60px */
    
    /* 现代间距系统 */
    --space-1: 0.25rem;  /* 4px */
    --space-2: 0.5rem;   /* 8px */
    --space-3: 0.75rem;  /* 12px */
    --space-4: 1rem;     /* 16px */
    --space-5: 1.25rem;  /* 20px */
    --space-6: 1.5rem;   /* 24px */
    --space-8: 2rem;     /* 32px */
    --space-10: 2.5rem;  /* 40px */
    --space-12: 3rem;    /* 48px */
    --space-16: 4rem;    /* 64px */
    --space-20: 5rem;    /* 80px */
    --space-24: 6rem;    /* 96px */
    
    /* 苹果风格动画 */
    --ease-out-cubic: cubic-bezier(0.33, 1, 0.68, 1);
    --ease-in-out-cubic: cubic-bezier(0.65, 0, 0.35, 1);
    --transition-fast: 0.15s var(--ease-out-cubic);
    --transition-normal: 0.25s var(--ease-out-cubic);
    --transition-slow: 0.4s var(--ease-out-cubic);
    
    /* 现代渐变 */
    --gradient-primary: linear-gradient(135deg, #007AFF 0%, #5AC8FA 100%);
    --gradient-secondary: linear-gradient(135deg, #5856D6 0%, #AF52DE 100%);
    --gradient-surface: linear-gradient(180deg, #FFFFFF 0%, #F2F2F7 100%);
    --gradient-glass: linear-gradient(135deg, rgba(255, 255, 255, 0.1) 0%, rgba(255, 255, 255, 0.05) 100%);
    
    /* 移动端优化变量 */
    --mobile-padding: var(--space-5);
    --mobile-margin: var(--space-4);
    --touch-target: 44px;
    --mobile-nav-height: 60px;
}

body {
    font-family: var(--font-family);
    background: var(--background-primary);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
    font-size: var(--text-base);
    font-weight: 400;
    letter-spacing: -0.02em;
    /* 苹果风格抗锯齿 */
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    /* 优化移动端滚动 */
    -webkit-overflow-scrolling: touch;
    /* 防止移动端缩放 */
    touch-action: manipulation;
    /* 现代背景渐变 */
    background: var(--gradient-surface);
    min-height: 100vh;
}

/* 现代化导航栏 */
.navbar {
    background: rgba(255, 255, 255, 0.8);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
    border-bottom: 1px solid var(--separator);
    position: sticky;
    top: 0;
    z-index: 1000;
    transition: var(--transition-normal);
    height: var(--mobile-nav-height);
    display: flex;
    align-items: center;
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--space-6);
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
    height: 100%;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: var(--space-3);
    font-size: var(--text-xl);
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
    letter-spacing: -0.02em;
}

.nav-brand i {
    font-size: var(--text-2xl);
    color: var(--primary-color);
    filter: drop-shadow(0 0 8px rgba(0, 122, 255, 0.3));
}

.nav-controls {
    display: flex;
    align-items: center;
    gap: var(--space-4);
}

.lang-switch {
    background: var(--surface-secondary);
    backdrop-filter: blur(10px);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-full);
    padding: var(--space-2) var(--space-4);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition-normal);
    min-height: var(--touch-target);
    display: flex;
    align-items: center;
    justify-content: center;
}

.lang-switch:hover {
    background: var(--primary-color);
    color: var(--text-inverse);
    transform: scale(1.05);
    box-shadow: var(--shadow-md);
}

.nav-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 16px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: clamp(18px, 4vw, 20px);
    font-weight: 600;
    color: var(--text-primary);
    /* 确保品牌名称可点击区域足够大 */
    min-height: var(--touch-target-size);
}

.nav-brand i {
    color: var(--primary-color);
    font-size: clamp(20px, 5vw, 24px);
}

.lang-switch {
    background: var(--primary-color);
    color: white;
    border: none;
    padding: 10px 18px;
    border-radius: 22px;
    font-size: clamp(13px, 3vw, 14px);
    font-weight: 500;
    cursor: pointer;
    transition: var(--transition);
    /* 确保按钮足够大易于点击 */
    min-height: var(--touch-target-size);
    min-width: 64px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.lang-switch:hover {
    background: #0056CC;
    transform: translateY(-1px);
}

/* 现代主容器 */
.main-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: var(--space-10) var(--space-6);
    position: relative;
}

/* 苹果风格英雄区域 */
.hero-section {
    text-align: center;
    padding: var(--space-20) 0 var(--space-16);
    position: relative;
    background: linear-gradient(135deg, 
        rgba(0, 122, 255, 0.05) 0%, 
        rgba(88, 86, 214, 0.05) 50%, 
        rgba(255, 59, 48, 0.05) 100%);
    border-radius: var(--radius-2xl);
    margin-bottom: var(--space-16);
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-glass);
    backdrop-filter: blur(20px);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-2xl);
    z-index: -1;
}

.hero-section h1 {
    font-size: clamp(var(--text-3xl), 6vw, var(--text-6xl));
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: var(--space-6);
    letter-spacing: -0.04em;
    line-height: 1.1;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-section p {
    font-size: clamp(var(--text-lg), 4vw, var(--text-xl));
    color: var(--text-secondary);
    margin-bottom: var(--space-8);
    font-weight: 400;
    line-height: 1.5;
    max-width: 600px;
    margin-left: auto;
    margin-right: auto;
}

/* 预设提示样式 */
.preset-tooltip {
    position: absolute;
    background: var(--primary-color);
    color: white;
    padding: 8px 12px;
    border-radius: 6px;
    font-size: 12px;
    z-index: 1000;
    opacity: 0;
    transform: translateY(-100%);
    transition: all 0.3s ease;
    pointer-events: none;
    margin-top: -8px;
    /* 移动端优化 */
    max-width: 90vw;
    word-wrap: break-word;
}

/* 增强的结果框样式 */
.result-box {
    margin-top: 24px;
    padding: 20px;
    background: var(--card-background);
    border-radius: var(--border-radius);
    box-shadow: var(--shadow-medium);
    border-left: 4px solid var(--primary-color);
}

.result-box .highlight {
    color: var(--primary-color);
    font-weight: 600;
}

/* 专业建议框样式 */
.result-box .advice-box {
    margin-top: 16px;
    padding: 12px;
    background: #f8f9fa;
    border-radius: 8px;
    border-left: 3px solid var(--secondary-color);
}

/* 选择器样式增强 */
select {
    width: 100%;
    padding: 12px;
    border: 2px solid var(--border-color);
    border-radius: var(--border-radius);
    font-size: 16px;
    background: white;
    transition: var(--transition);
}

select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 122, 255, 0.1);
}

/* 联系信息样式 */
.footer a {
    transition: var(--transition);
}

.footer a:hover {
    color: var(--secondary-color) !important;
    text-decoration: underline !important;
}

/* 标题区域 */
.hero-section {
    text-align: center;
    margin-bottom: clamp(40px, 8vw, 60px);
    padding: clamp(40px, 10vw, 60px) clamp(16px, 4vw, 24px);
    background: var(--gradient-bg);
    margin-left: calc(-1 * clamp(16px, 4vw, 24px));
    margin-right: calc(-1 * clamp(16px, 4vw, 24px));
    margin-top: calc(-1 * clamp(20px, 5vw, 40px));
    color: white;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 20"><defs><radialGradient id="a" cx="50%" cy="50%"><stop offset="0%" stop-color="rgba(255,255,255,0.1)"/><stop offset="100%" stop-color="rgba(255,255,255,0)"/></radialGradient></defs><rect width="100" height="20" fill="url(%23a)"/></svg>');
    opacity: 0.3;
}

.hero-section h1 {
    font-size: clamp(32px, 6vw, 48px);
    font-weight: 700;
    margin-bottom: 16px;
    position: relative;
    z-index: 1;
}

.hero-section p {
    font-size: clamp(16px, 3vw, 20px);
    opacity: 0.9;
    font-weight: 400;
    position: relative;
    z-index: 1;
}

/* 苹果风格计算器网格 */
.calculator-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(300px, 100%), 1fr));
    gap: var(--space-6);
    margin-bottom: var(--space-16);
}

/* 现代化计算器卡片 */
.calculator-card {
    background: var(--surface-primary);
    border-radius: var(--radius-xl);
    padding: var(--space-8) var(--space-6);
    text-align: center;
    cursor: pointer;
    transition: var(--transition-normal);
    border: 1px solid var(--border-secondary);
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
    backdrop-filter: blur(10px);
    min-height: 200px;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    /* 移动端触摸优化 */
    min-height: var(--touch-target);
    -webkit-tap-highlight-color: transparent;
}

.calculator-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: var(--gradient-primary);
    opacity: 0;
    transition: var(--transition-slow);
    border-radius: var(--radius-xl);
}

.calculator-card:hover {
    transform: translateY(-8px) scale(1.02);
    box-shadow: var(--shadow-xl);
    border-color: var(--primary-color);
}

.calculator-card:hover::before {
    opacity: 0.08;
}

.calculator-card:active {
    transform: translateY(-4px) scale(1.01);
    transition: var(--transition-fast);
}

.card-icon {
    font-size: clamp(2.5rem, 5vw, 3rem);
    color: var(--primary-color);
    margin-bottom: var(--space-4);
    position: relative;
    z-index: 2;
    filter: drop-shadow(0 4px 8px rgba(0, 122, 255, 0.2));
    transition: var(--transition-normal);
}

.calculator-card:hover .card-icon {
    transform: scale(1.1) rotate(5deg);
    color: var(--primary-hover);
}

.calculator-card h3 {
    font-size: clamp(var(--text-lg), 4vw, var(--text-xl));
    font-weight: 600;
    margin-bottom: var(--space-3);
    color: var(--text-primary);
    position: relative;
    z-index: 2;
    letter-spacing: -0.02em;
}

.calculator-card p {
    color: var(--text-secondary);
    font-size: clamp(var(--text-sm), 3vw, var(--text-base));
    line-height: 1.5;
    position: relative;
    z-index: 2;
    max-width: 250px;
}

/* 计算器内容 */
.calculator-content {
    background: var(--card-background);
    border-radius: var(--border-radius-large);
    padding: 40px;
    box-shadow: var(--shadow-medium);
    border: 1px solid var(--border-color);
    margin-top: 40px;
    transition: var(--transition);
}

.calculator-content.hidden {
    display: none;
}

.back-button {
    background: transparent;
    border: 1px solid var(--border-color);
    color: var(--text-secondary);
    padding: 12px 20px;
    border-radius: var(--border-radius);
    font-size: 14px;
    cursor: pointer;
    margin-bottom: 32px;
    display: flex;
    align-items: center;
    gap: 8px;
    transition: var(--transition);
    font-weight: 500;
}

.back-button:hover {
    background: var(--background-color);
    color: var(--text-primary);
    transform: translateX(-2px);
}

.calculator {
    max-width: 600px;
    margin: 0 auto;
}

.calculator.hidden {
    display: none;
}

.calculator h2 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 32px;
    color: var(--text-primary);
    text-align: center;
}

/* 现代化表单设计 */
.input-group {
    margin-bottom: var(--space-6);
    position: relative;
}

.input-group label {
    display: block;
    font-size: var(--text-sm);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-2);
    letter-spacing: -0.01em;
}

.input-group input,
.input-group select {
    width: 100%;
    padding: var(--space-4) var(--space-4);
    border: 1px solid var(--border-primary);
    border-radius: var(--radius-md);
    font-size: var(--text-base);
    background: var(--surface-primary);
    color: var(--text-primary);
    transition: var(--transition-normal);
    font-family: var(--font-family);
    box-sizing: border-box;
    backdrop-filter: blur(10px);
    /* 移动端触摸优化 */
    min-height: var(--touch-target);
    -webkit-appearance: none;
    -moz-appearance: none;
    appearance: none;
}

.input-group input:focus,
.input-group select:focus {
    outline: none;
    border-color: var(--primary-color);
    box-shadow: 0 0 0 4px rgba(0, 122, 255, 0.1);
    background: var(--surface-elevated);
    transform: scale(1.02);
}

.input-group input::placeholder {
    color: var(--text-tertiary);
    font-weight: 400;
}

/* 苹果风格按钮 */
.calculate-btn {
    width: 100%;
    background: var(--gradient-primary);
    color: var(--text-inverse);
    border: none;
    padding: var(--space-4) var(--space-6);
    border-radius: var(--radius-md);
    font-size: var(--text-base);
    font-weight: 600;
    cursor: pointer;
    margin: var(--space-8) 0 var(--space-6) 0;
    transition: var(--transition-normal);
    position: relative;
    overflow: hidden;
    box-shadow: var(--shadow-md);
    letter-spacing: -0.02em;
    /* 移动端触摸优化 */
    min-height: var(--touch-target);
    -webkit-tap-highlight-color: transparent;
    touch-action: manipulation;
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-lg);
    background: var(--gradient-secondary);
}

.calculate-btn:active {
    transform: translateY(0);
    transition: var(--transition-fast);
}

/* 返回按钮现代化 */
.back-button {
    display: inline-flex;
    align-items: center;
    gap: var(--space-2);
    background: var(--surface-secondary);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-full);
    padding: var(--space-3) var(--space-5);
    font-size: var(--text-sm);
    font-weight: 500;
    color: var(--text-primary);
    cursor: pointer;
    transition: var(--transition-normal);
    margin-bottom: var(--space-6);
    backdrop-filter: blur(10px);
}

.back-button:hover {
    background: var(--primary-color);
    color: var(--text-inverse);
    transform: translateX(-4px);
    box-shadow: var(--shadow-md);
}

.calculate-btn::before {
    content: '';
    position: absolute;
    top: 50%;
    left: 50%;
    width: 0;
    height: 0;
    background: rgba(255, 255, 255, 0.2);
    border-radius: 50%;
    transform: translate(-50%, -50%);
    transition: all 0.6s ease;
}

.calculate-btn:hover::before {
    width: 300px;
    height: 300px;
}

.calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-medium);
}

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

/* 结果框 */
.result-box {
    background: linear-gradient(135deg, #E8F5E8, #F0F9FF);
    border: 1px solid #D1FAE5;
    border-radius: var(--border-radius);
    padding: 24px;
    margin-top: 24px;
    animation: fadeInUp 0.5s ease;
}

.result-box.hidden {
    display: none;
}

.result-box h3 {
    color: #059669;
    font-size: 18px;
    font-weight: 600;
    margin-bottom: 16px;
}

.result-box p {
    margin-bottom: 8px;
    color: #374151;
    font-weight: 500;
}

/* 现代化结果显示 */
.result-box {
    background: var(--surface-primary);
    border: 1px solid var(--border-secondary);
    border-radius: var(--radius-lg);
    padding: var(--space-6);
    margin-top: var(--space-6);
    box-shadow: var(--shadow-md);
    backdrop-filter: blur(20px);
    position: relative;
    overflow: hidden;
    animation: slideInUp 0.4s var(--ease-out-cubic);
}

.result-box::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
}

.result-box h3 {
    font-size: var(--text-lg);
    font-weight: 600;
    color: var(--text-primary);
    margin-bottom: var(--space-4);
    letter-spacing: -0.02em;
}

.result-box p {
    font-size: var(--text-base);
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: var(--space-3);
}

.result-box .highlight {
    color: var(--success-color);
    font-weight: 700;
    font-size: var(--text-lg);
    background: rgba(48, 209, 88, 0.1);
    padding: var(--space-1) var(--space-2);
    border-radius: var(--radius-sm);
}

/* 苹果风格页脚 */
.footer {
    text-align: center;
    padding: var(--space-16) var(--space-6) var(--space-8);
    color: var(--text-secondary);
    font-size: var(--text-sm);
    background: var(--gradient-surface);
    border-top: 1px solid var(--separator);
    margin-top: var(--space-20);
    backdrop-filter: blur(20px);
}

.footer p {
    margin-bottom: var(--space-2);
    line-height: 1.5;
}

.footer a {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition-normal);
}

.footer a:hover {
    color: var(--primary-hover);
    text-decoration: underline;
}

/* 工具类 */
.hidden {
    display: none !important;
}

/* 苹果风格动画 */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

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

@keyframes scaleIn {
    from {
        opacity: 0;
        transform: scale(0.95);
    }
    to {
        opacity: 1;
        transform: scale(1);
    }
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

/* 页面加载动画 */
.main-container {
    animation: fadeIn 0.6s var(--ease-out-cubic);
}

.calculator-card {
    animation: fadeInUp 0.5s var(--ease-out-cubic);
}

.calculator-card:nth-child(1) { animation-delay: 0.1s; }
.calculator-card:nth-child(2) { animation-delay: 0.2s; }
.calculator-card:nth-child(3) { animation-delay: 0.3s; }
.calculator-card:nth-child(4) { animation-delay: 0.4s; }

.hero-section {
    animation: scaleIn 0.7s var(--ease-out-cubic);
}

@keyframes fadeIn {
    from {
        opacity: 0;
    }
    to {
        opacity: 1;
    }
}

.fade-in {
    animation: fadeIn 0.5s ease;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .main-container {
        padding: 20px 16px;
    }
    
    .hero-section {
        margin: -20px -16px 40px -16px;
        padding: 40px 16px;
    }
    
    .calculator-grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }
    
    .calculator-card {
        padding: 24px 20px;
    }
    
    .calculator-content {
        padding: 24px 20px;
    }
    
    .nav-container {
        padding: 12px 16px;
    }
    
    .nav-brand {
        font-size: 18px;
    }
    
    .nav-brand i {
        font-size: 20px;
    }
}

@media (max-width: 480px) {
    .calculator-card {
        padding: 20px 16px;
    }
    
    .card-icon {
        font-size: 36px;
        margin-bottom: 16px;
    }
    
    .calculator-card h3 {
        font-size: 18px;
    }
    
    .calculator h2 {
        font-size: 24px;
    }
    
    .input-group input,
    .input-group select {
        padding: 14px;
        font-size: 15px;
    }
    
    .calculate-btn {
        padding: 16px 20px;
        font-size: 15px;
    }
}

/* 特殊样式 */
#plate-area {
    appearance: none;
    background-image: url("data:image/svg+xml;charset=US-ASCII,<svg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 4 5'><path fill='%23666' d='M2 0L0 2h4zm0 5L0 3h4z'/></svg>");
    background-repeat: no-repeat;
    background-position: right 12px center;
    background-size: 12px;
    padding-right: 40px;
}

#custom-area.hidden {
    display: none;
}

/* 移动端媒体查询优化 */
@media (max-width: 768px) {
    .hero {
        padding: clamp(60px, 15vw, 80px) 0 clamp(40px, 10vw, 60px);
    }
    
    .hero h1 {
        font-size: clamp(2rem, 8vw, 2.5rem);
        line-height: 1.2;
    }
    
    .hero p {
        font-size: clamp(1rem, 4vw, 1.1rem);
        margin-bottom: clamp(24px, 6vw, 32px);
    }
    
    .calculator-grid {
        grid-template-columns: 1fr;
        gap: clamp(12px, 3vw, 16px);
    }
    
    .calculator-card {
        padding: clamp(20px, 5vw, 24px);
        margin-bottom: clamp(12px, 3vw, 16px);
    }
    
    .calculator-card h3 {
        font-size: clamp(1.1rem, 4.5vw, 1.25rem);
    }
    
    .calculator-card p {
        font-size: clamp(0.85rem, 3.5vw, 0.95rem);
    }
    
    .language-toggle {
        padding: clamp(8px, 2vw, 10px) clamp(12px, 3vw, 16px);
        font-size: clamp(0.8rem, 3vw, 0.9rem);
    }
    
    .tooltip {
        font-size: clamp(0.75rem, 2.5vw, 0.85rem);
        padding: clamp(6px, 1.5vw, 8px) clamp(8px, 2vw, 10px);
        max-width: 90vw;
    }
    
    /* 移动端表单优化 */
    .input-group input,
    .input-group select {
        font-size: 16px; /* 防止iOS缩放 */
    }
    
    /* 移动端结果显示优化 */
    .result-box {
        padding: clamp(16px, 4vw, 20px);
        font-size: clamp(0.9rem, 3.5vw, 1rem);
    }
    
    /* 移动端联系信息优化 */
    .contact-info {
        flex-direction: column;
        gap: clamp(8px, 2vw, 12px);
    }
    
    .contact-info a {
        font-size: clamp(0.8rem, 3vw, 0.9rem);
    }
}

/* 小屏移动设备优化 */
@media (max-width: 480px) {
    .container {
        padding: 0 var(--mobile-padding);
    }
    
    .navbar .container {
        padding: 0 var(--mobile-padding);
    }
    
    .calculator-card {
        border-radius: var(--border-radius);
    }
    
    /* 横屏优化 */
    @media (orientation: landscape) and (max-height: 500px) {
        .hero {
            padding: clamp(30px, 8vw, 40px) 0 clamp(20px, 5vw, 30px);
        }
        
        .hero h1 {
            font-size: clamp(1.5rem, 6vw, 2rem);
        }
        
        .calculator-card {
            padding: clamp(16px, 4vw, 20px);
        }
    }
}

/* 苹果风格深色模式 */
@media (prefers-color-scheme: dark) {
    :root {
        --background-primary: #000000;
        --background-secondary: #1C1C1E;
        --background-tertiary: #2C2C2E;
        --surface-primary: #1C1C1E;
        --surface-secondary: rgba(28, 28, 30, 0.8);
        --surface-elevated: #2C2C2E;
        
        --text-primary: #FFFFFF;
        --text-secondary: #8E8E93;
        --text-tertiary: #48484A;
        
        --border-primary: rgba(84, 84, 88, 0.4);
        --border-secondary: rgba(84, 84, 88, 0.2);
        --separator: rgba(84, 84, 88, 0.65);
        
        --gradient-surface: linear-gradient(180deg, #000000 0%, #1C1C1E 100%);
    }
    
    .navbar {
        background: rgba(28, 28, 30, 0.8);
        border-bottom-color: var(--separator);
    }
    
    .calculator-card {
        background: var(--surface-primary);
        border-color: var(--border-primary);
    }
    
    .result-box {
        background: var(--surface-elevated);
        border-color: var(--border-primary);
    }
    
    .input-group input,
    .input-group select {
        background: var(--surface-elevated);
        border-color: var(--border-primary);
    }
}