:root {
    --surface-0: #05070C;
    --surface-1: #0A0D12;
    --surface-2: #0F131C;
    --surface-3: #161D2B;
    --surface-4: #1E2636;

    --primary: #38BDF8;
    --primary-dark: #3B6DFF;
    --accent: #6EE7B7;
    --accent-secondary: #38BDF8;

    --text-primary: #F8FAFC;
    --text-secondary: #94A3B8;
    --text-tertiary: #64748B;

    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --radius-full: 999px;

    /* 线条和浅色叠层：深色主题是半透明白，浅色主题换成半透明深色 */
    --w02: rgba(255, 255, 255, 0.02);
    --w03: rgba(255, 255, 255, 0.03);
    --w04: rgba(255, 255, 255, 0.04);
    --w05: rgba(255, 255, 255, 0.05);
    --w06: rgba(255, 255, 255, 0.06);
    --w1: rgba(255, 255, 255, 0.1);
    --heading-from: #ffffff;
    --heading-to: rgba(255, 255, 255, 0.8);

    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.4);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.5);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.6);
}

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

html {
    scroll-behavior: smooth;
}

body {
    /* 系统字体：不从外网加载字体，国内也不会卡首屏。苹果设备用苹方 / San Francisco，Windows 用微软雅黑 */
    font-family: -apple-system, BlinkMacSystemFont, 'SF Pro Text', 'PingFang SC', 'Segoe UI', 'Microsoft YaHei', 'Noto Sans SC', 'Helvetica Neue', Arial, sans-serif;
    background: var(--surface-0);
    color: var(--text-primary);
    line-height: 1.6;
    overflow-x: hidden;
}

.container {
    max-width: clamp(320px, 90vw, 1280px);
    margin: 0 auto;
    padding: 0 clamp(1rem, 4vw, 2rem);
}

/* Navbar */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(5, 7, 12, 0.8);
    backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 72px;
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: clamp(1.25rem, 2vw, 1.5rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    text-decoration: none;
}

.logo-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-menu {
    display: flex;
    gap: clamp(1rem, 3vw, 2.5rem);
    list-style: none;
}

.nav-menu a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    font-weight: 500;
    transition: color 0.3s;
}

.nav-menu a:hover,
.nav-menu a.active {
    color: var(--text-primary);
}

.nav-actions {
    display: flex;
    align-items: center;
    gap: clamp(0.75rem, 2vw, 1rem);
}

.btn-text {
    padding: clamp(0.5rem, 1.5vw, 0.625rem) clamp(1rem, 2vw, 1.25rem);
    color: var(--text-primary);
    text-decoration: none;
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    font-weight: 500;
    transition: color 0.3s;
}

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

.btn-primary {
    padding: clamp(0.5rem, 1.5vw, 0.625rem) clamp(1rem, 2.5vw, 1.5rem);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-decoration: none;
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(56, 189, 248, 0.3);
}

/* Hero Section */
.hero {
    position: relative;
    min-height: 100vh;
    display: flex;
    align-items: center;
    padding-top: 72px;
    overflow: hidden;
}

.hero-bg {
    position: absolute;
    inset: 0;
    z-index: 0;
}

.grid-overlay {
    position: absolute;
    inset: 0;
    background-image:
        linear-gradient(rgba(56, 189, 248, 0.03) 1px, transparent 1px),
        linear-gradient(90deg, rgba(56, 189, 248, 0.03) 1px, transparent 1px);
    background-size: 50px 50px;
    mask-image: radial-gradient(ellipse 80% 60% at 50% 40%, black 0%, transparent 70%);
}

#particles {
    position: absolute;
    inset: 0;
    opacity: 0.4;
}

.hero-content {
    position: relative;
    z-index: 1;
    max-width: 900px;
    padding: clamp(2rem, 8vw, 4rem) 0;
}

.hero-badge {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: clamp(0.5rem, 1.5vw, 0.625rem) clamp(1rem, 2vw, 1.25rem);
    background: var(--surface-2);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: var(--radius-full);
    font-size: clamp(0.75rem, 1.5vw, 0.875rem);
    font-weight: 500;
    color: var(--text-secondary);
    margin-bottom: clamp(1.5rem, 4vw, 2rem);
}

.badge-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--primary);
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.hero-title {
    font-size: clamp(2.5rem, 8vw, 4.5rem);
    font-weight: 800;
    line-height: 1.1;
    letter-spacing: -0.03em;
    margin-bottom: clamp(1rem, 3vw, 1.5rem);
}

.gradient-text {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 50%, var(--accent) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-subtitle {
    font-size: clamp(1rem, 2vw, 1.25rem);
    color: var(--text-secondary);
    line-height: 1.7;
    margin-bottom: clamp(2rem, 5vw, 3rem);
}

.hero-actions {
    display: flex;
    gap: clamp(0.75rem, 2vw, 1rem);
    margin-bottom: clamp(3rem, 6vw, 4rem);
}

.btn-hero {
    padding: clamp(0.875rem, 2vw, 1rem) clamp(1.5rem, 3vw, 2rem);
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-decoration: none;
    font-size: clamp(0.9375rem, 1.5vw, 1.0625rem);
    font-weight: 600;
    border-radius: var(--radius-full);
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn-hero:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(56, 189, 248, 0.4);
}

.btn-outline {
    padding: clamp(0.875rem, 2vw, 1rem) clamp(1.5rem, 3vw, 2rem);
    background: transparent;
    color: var(--text-primary);
    text-decoration: none;
    font-size: clamp(0.9375rem, 1.5vw, 1.0625rem);
    font-weight: 600;
    border: 2px solid var(--surface-3);
    border-radius: var(--radius-full);
    transition: all 0.2s;
}

.btn-outline:hover {
    border-color: var(--primary);
    background: rgba(56, 189, 248, 0.05);
}

.hero-stats {
    display: flex;
    align-items: center;
    gap: clamp(1.5rem, 4vw, 3rem);
}

.stat-item {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.stat-value {
    font-size: clamp(1.5rem, 3vw, 2rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    color: var(--text-primary);
}

.stat-label {
    font-size: clamp(0.75rem, 1.5vw, 0.875rem);
    color: var(--text-tertiary);
}

.stat-divider {
    width: 1px;
    height: 40px;
    background: var(--surface-3);
}

/* Features Section */
.features {
    padding: clamp(4rem, 10vw, 8rem) 0;
    background: var(--surface-1);
}

.section-header {
    text-align: center;
    margin-bottom: clamp(3rem, 6vw, 4rem);
}

.section-title {
    font-size: clamp(2rem, 5vw, 3rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: clamp(0.75rem, 2vw, 1rem);
}

.section-subtitle {
    font-size: clamp(1rem, 2vw, 1.125rem);
    color: var(--text-secondary);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr));
    gap: clamp(1.5rem, 3vw, 2rem);
}

.feature-card {
    padding: clamp(1.5rem, 3vw, 2rem);
    background: var(--surface-2);
    border: 1px solid var(--surface-3);
    border-radius: var(--radius-lg);
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-4px);
    border-color: rgba(56, 189, 248, 0.3);
    box-shadow: var(--shadow-md);
}

.feature-icon {
    width: clamp(3rem, 8vw, 3.5rem);
    height: clamp(3rem, 8vw, 3.5rem);
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(56, 189, 248, 0.1) 0%, rgba(59, 109, 255, 0.1) 100%);
    border: 1px solid rgba(56, 189, 248, 0.2);
    border-radius: var(--radius-md);
    color: var(--primary);
    margin-bottom: clamp(1rem, 2vw, 1.25rem);
}

.feature-title {
    font-size: clamp(1.125rem, 2vw, 1.25rem);
    font-weight: 600;
    margin-bottom: clamp(0.5rem, 1.5vw, 0.75rem);
}

.feature-desc {
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    color: var(--text-secondary);
    line-height: 1.6;
}

/* Models Section */
.models {
    padding: clamp(4rem, 10vw, 8rem) 0;
    background: var(--surface-0);
}

.models-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 320px), 1fr));
    gap: clamp(1.5rem, 3vw, 2rem);
}

.model-card {
    padding: clamp(2rem, 4vw, 2.5rem);
    background: var(--surface-2);
    border: 1px solid var(--surface-3);
    border-radius: var(--radius-lg);
    transition: all 0.3s;
    display: flex;
    flex-direction: column;
}

.model-card:hover {
    transform: translateY(-4px);
    border-color: rgba(56, 189, 248, 0.3);
}

.model-card.featured {
    border-color: var(--primary);
    background: linear-gradient(135deg, var(--surface-2) 0%, rgba(56, 189, 248, 0.05) 100%);
}

.model-badge {
    display: inline-block;
    align-self: flex-start;
    padding: clamp(0.375rem, 1vw, 0.5rem) clamp(0.75rem, 1.5vw, 1rem);
    background: rgba(56, 189, 248, 0.1);
    color: var(--primary);
    font-size: clamp(0.75rem, 1.5vw, 0.875rem);
    font-weight: 600;
    border-radius: var(--radius-full);
    margin-bottom: clamp(1rem, 2vw, 1.5rem);
}

.model-name {
    font-size: clamp(1.5rem, 3vw, 1.75rem);
    font-weight: 700;
    margin-bottom: clamp(0.75rem, 1.5vw, 1rem);
}

.model-desc {
    font-size: clamp(0.9375rem, 1.5vw, 1rem);
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: clamp(1.5rem, 3vw, 2rem);
}

.model-stats {
    display: flex;
    flex-direction: column;
    gap: clamp(0.75rem, 1.5vw, 1rem);
    padding: clamp(1rem, 2vw, 1.25rem) 0;
    border-top: 1px solid var(--surface-3);
    border-bottom: 1px solid var(--surface-3);
    margin-bottom: clamp(1.5rem, 3vw, 2rem);
}

.model-stat {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.model-stat .stat-label {
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    color: var(--text-tertiary);
}

.model-stat .stat-value {
    font-size: clamp(0.9375rem, 1.5vw, 1rem);
    font-weight: 600;
    color: var(--primary);
}

.btn-model {
    padding: clamp(0.75rem, 1.5vw, 0.875rem) 0;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    color: white;
    text-decoration: none;
    text-align: center;
    font-size: clamp(0.9375rem, 1.5vw, 1rem);
    font-weight: 600;
    border-radius: var(--radius-md);
    transition: all 0.2s;
}

.btn-model:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(56, 189, 248, 0.3);
}

/* CTA Section */
.cta {
    padding: clamp(4rem, 10vw, 6rem) 0;
    background: linear-gradient(135deg, var(--surface-2) 0%, rgba(56, 189, 248, 0.05) 100%);
    border-top: 1px solid var(--surface-3);
    border-bottom: 1px solid var(--surface-3);
}

.cta-content {
    text-align: center;
    max-width: 700px;
    margin: 0 auto;
}

.cta-title {
    font-size: clamp(2rem, 5vw, 2.5rem);
    font-weight: 700;
    letter-spacing: -0.02em;
    margin-bottom: clamp(0.75rem, 2vw, 1rem);
}

.cta-subtitle {
    font-size: clamp(1rem, 2vw, 1.125rem);
    color: var(--text-secondary);
    margin-bottom: clamp(2rem, 4vw, 2.5rem);
}

/* Footer */
.footer {
    padding: clamp(3rem, 6vw, 4rem) 0 clamp(1.5rem, 3vw, 2rem);
    background: var(--surface-1);
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 200px), 1fr));
    gap: clamp(2rem, 4vw, 3rem);
    margin-bottom: clamp(2rem, 4vw, 3rem);
}

.footer-logo {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: clamp(1.25rem, 2vw, 1.5rem);
    font-weight: 700;
    margin-bottom: clamp(0.75rem, 1.5vw, 1rem);
}

.footer-logo span {
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.footer-desc {
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    color: var(--text-secondary);
    line-height: 1.6;
}

.footer-title {
    font-size: clamp(0.9375rem, 1.5vw, 1rem);
    font-weight: 600;
    margin-bottom: clamp(0.75rem, 1.5vw, 1rem);
}

.footer-links {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: clamp(0.5rem, 1vw, 0.625rem);
}

.footer-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    transition: color 0.3s;
}

.footer-links a:hover {
    color: var(--primary);
}

.footer-bottom {
    padding-top: clamp(1.5rem, 3vw, 2rem);
    border-top: 1px solid var(--surface-3);
    text-align: center;
    font-size: clamp(0.875rem, 1.5vw, 0.9375rem);
    color: var(--text-tertiary);
}

/* Button Ripple Effect */
.btn-primary,
.btn-hero,
.btn-model {
    position: relative;
    overflow: hidden;
}

.ripple {
    position: absolute;
    border-radius: 50%;
    background: rgba(255, 255, 255, 0.3);
    transform: scale(0);
    animation: ripple-animation 0.6s ease-out;
    pointer-events: none;
}

@keyframes ripple-animation {
    to {
        transform: scale(4);
        opacity: 0;
    }
}

/* Responsive */
@media (max-width: 768px) {
    .navbar {
        padding: 1rem 0;
    }

    .nav-menu {
        display: none;
        position: fixed;
        top: 0;
        right: -100%;
        width: 280px;
        height: 100vh;
        background: var(--surface-1);
        border-left: 1px solid var(--surface-3);
        flex-direction: column;
        padding: 5rem 2rem 2rem;
        gap: 1.5rem;
        z-index: 1000;
        transition: right 0.3s ease;
    }

    .nav-menu.open {
        display: flex;
        right: 0;
    }

    .mobile-menu-btn {
        display: block;
        background: none;
        border: none;
        color: var(--text-primary);
        cursor: pointer;
        padding: 0.5rem;
        z-index: 1001;
    }

    .mobile-menu-btn span {
        display: block;
        width: 24px;
        height: 2px;
        background: var(--text-primary);
        margin: 5px 0;
        transition: all 0.3s ease;
    }

    .mobile-menu-overlay {
        display: none;
        position: fixed;
        top: 0;
        left: 0;
        width: 100%;
        height: 100vh;
        background: rgba(0, 0, 0, 0.5);
        z-index: 999;
    }

    .mobile-menu-overlay.open {
        display: block;
    }

    .hero-stats {
        flex-wrap: wrap;
        justify-content: center;
        gap: 1.5rem;
    }

    .hero-actions {
        flex-direction: column;
        width: 100%;
        gap: 1rem;
    }

    .hero-actions a {
        width: 100%;
        text-align: center;
    }

    .features-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }

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

    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }

    .footer-section {
        margin-bottom: 2rem;
    }
}
/* ==========================================
   浅色主题：给 <html> 加 data-theme="light" 即生效（用户在顶部栏切换，保存在 localStorage）
   ========================================== */
html[data-theme="light"] {
    color-scheme: light;
    --surface-0: #F1F5F9;
    --surface-1: #FFFFFF;
    --surface-2: #FFFFFF;
    --surface-3: #F1F5F9;
    --surface-4: #E2E8F0;

    --primary: #0284C7;
    --primary-dark: #2563EB;
    --accent: #059669;
    --accent-secondary: #0284C7;

    --text-primary: #0F172A;
    --text-secondary: #475569;
    --text-tertiary: #64748B;

    --w02: rgba(15, 23, 42, 0.03);
    --w03: rgba(15, 23, 42, 0.05);
    --w04: rgba(15, 23, 42, 0.05);
    --w05: rgba(15, 23, 42, 0.09);
    --w06: rgba(15, 23, 42, 0.09);
    --w1: rgba(15, 23, 42, 0.16);
    --heading-from: #0F172A;
    --heading-to: #334155;

    --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.08);
    --shadow-md: 0 4px 16px rgba(15, 23, 42, 0.1);
    --shadow-lg: 0 8px 32px rgba(15, 23, 42, 0.12);
}

/* 主题切换按钮（顶部栏，头像旁） */
.theme-toggle {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    border: 1px solid var(--w1);
    background: var(--surface-3);
    color: var(--text-primary);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    transition: background 0.2s ease, border-color 0.2s ease;
}
.theme-toggle:hover { border-color: var(--accent); }
.theme-toggle svg { display: block; }
.theme-toggle .icon-sun { display: none; }
html[data-theme="light"] .theme-toggle .icon-moon { display: none; }
html[data-theme="light"] .theme-toggle .icon-sun { display: block; }

/* 手动交易 vs 自动交易 对比 */
.compare {
    padding: clamp(3rem, 8vw, 6rem) 0 0;
    background: var(--surface-1);
}
.compare-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 340px), 1fr));
    gap: clamp(1.25rem, 3vw, 2rem);
}
.compare-card {
    position: relative;
    overflow: hidden;
    border-radius: var(--radius-lg);
    padding: clamp(1.5rem, 3vw, 2rem);
    border: 1px solid;
}
.compare-card h3 {
    font-size: 1.125rem;
    font-weight: 700;
    margin-bottom: 1.25rem;
}
.compare-card ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.875rem;
    padding-bottom: 1.5rem;
    margin-bottom: 1.25rem;
    border-bottom: 1px solid var(--w1);
}
.compare-card li {
    display: flex;
    align-items: center;
    gap: 0.75rem;
    font-weight: 600;
}
.compare-quote {
    font-style: italic;
    font-weight: 600;
    font-size: 0.9375rem;
    padding-right: 5rem;
}
.compare-icon {
    position: absolute;
    right: 1rem;
    bottom: 1rem;
    opacity: 0.14;
}
.compare-dot {
    width: 8px;
    height: 8px;
    border-radius: 50%;
    background: #ef4444;
    flex-shrink: 0;
    margin: 0 6px;
}
.compare-check { flex-shrink: 0; color: #10b981; }

.compare-manual {
    background: rgba(239, 68, 68, 0.07);
    border-color: rgba(239, 68, 68, 0.35);
}
.compare-manual h3,
.compare-manual .compare-quote,
.compare-manual .compare-icon { color: #ef4444; }
.compare-manual li { color: var(--text-primary); }

.compare-auto {
    background: rgba(16, 185, 129, 0.07);
    border-color: rgba(16, 185, 129, 0.4);
    box-shadow: 0 0 40px rgba(16, 185, 129, 0.12);
}
.compare-auto h3,
.compare-auto .compare-quote,
.compare-auto .compare-icon { color: #10b981; }
.compare-auto li { color: var(--text-primary); }

/* 四大核心优势 */
.advantages {
    padding: clamp(3rem, 8vw, 6rem) 0;
    background: var(--surface-0);
}
.adv-accent {
    margin-left: 0.25em;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-dark) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}
.adv-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(min(100%, 250px), 1fr));
    gap: clamp(1rem, 2vw, 1.5rem);
}
.adv-card {
    display: flex;
    flex-direction: column;
    padding: clamp(1.25rem, 2.5vw, 1.75rem);
    background: var(--surface-2);
    border: 1px solid var(--w1);
    border-radius: var(--radius-lg);
    transition: border-color 0.3s, transform 0.3s;
}
.adv-card:hover {
    border-color: var(--primary);
    transform: translateY(-4px);
}
.adv-card h3 {
    font-size: 1.25rem;
    font-weight: 700;
    font-style: italic;
    margin-bottom: 1.25rem;
}
.adv-card ul {
    list-style: none;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
    flex: 1;
    padding-bottom: 1.25rem;
    margin-bottom: 1rem;
    border-bottom: 1px solid var(--w05);
    color: var(--text-secondary);
    font-size: 0.9375rem;
}
.adv-card li { display: flex; gap: 0.625rem; align-items: flex-start; }
.adv-dot {
    width: 6px;
    height: 6px;
    border-radius: 50%;
    background: var(--primary);
    flex-shrink: 0;
    margin-top: 0.6em;
}
.adv-foot {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 0.5rem;
    font-size: 0.8125rem;
    font-weight: 700;
    color: var(--primary);
}
.adv-icon { opacity: 0.25; flex-shrink: 0; }

/* 中英文切换按钮：样式和黑暗 / 明亮按钮一致 */
.lang-toggle {
    min-width: 40px;
    height: 40px;
    padding: 0 0.5rem;
    border-radius: 999px;
    border: 1px solid var(--w1);
    background: var(--surface-3);
    color: var(--text-primary);
    font-size: 0.8125rem;
    font-weight: 700;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    flex-shrink: 0;
    margin-right: 0.5rem;
    transition: border-color 0.2s ease;
}
.lang-toggle:hover { border-color: var(--accent); }
.user-menu .lang-toggle { margin-right: 0; }

/* ==========================================================
   手机端（以 iPhone 17 / 16 Pro 的 402×874 为基准，兼顾 375 到 440 宽）
   ========================================================== */
html { -webkit-text-size-adjust: 100%; text-size-adjust: 100%; }
a, button, select, label, input { -webkit-tap-highlight-color: transparent; }
button, a, select, input[type="button"], input[type="submit"] { touch-action: manipulation; } /* 去掉双击缩放的延迟 */

@media (max-width: 768px) {
    /* iOS Safari 在输入框字体小于 16px 时，点进去会自动放大页面 */
    input:not([type="checkbox"]):not([type="radio"]),
    select,
    textarea {
        font-size: 16px !important;
    }

    /* 刘海 / 灵动岛：固定的顶栏要避开 */
    .navbar {
        padding-top: calc(0.75rem + env(safe-area-inset-top));
        padding-bottom: 0.75rem;
    }
    .navbar .container {
        padding-left: max(1rem, env(safe-area-inset-left));
        padding-right: max(1rem, env(safe-area-inset-right));
    }

    /* 触控目标至少 44 点（苹果的建议） */
    .logo,
    .btn-text,
    .btn-primary {
        min-height: 44px;
        display: inline-flex;
        align-items: center;
    }
    .btn-primary { justify-content: center; }
    .lang-toggle { min-width: 44px; height: 44px; }

    /* iOS Safari 的 100vh 比可视区域高（把地址栏、工具栏也算进去），用动态视口高度 */
    .hero { min-height: 100vh; min-height: 100svh; }
    .nav-menu { height: 100vh; height: 100dvh; }
}

/* 窄屏（iPhone 的宽度）：官网顶栏放得下 Logo、语言按钮、登录、注册，不换行不挤压 */
@media (max-width: 480px) {
    .navbar .logo-text { font-size: 1.125rem; }
    .nav-content { gap: 0.5rem; }
    .nav-actions { gap: 0.125rem; flex-shrink: 0; }
    .nav-actions .btn-text,
    .nav-actions .btn-primary {
        white-space: nowrap;
        padding-left: 0.75rem;
        padding-right: 0.75rem;
    }
    .nav-actions .lang-toggle { margin-right: 0.125rem; }
}

/* 375 宽及更窄（iPhone mini / SE）：英文的"Sign up free"也要完整放进顶栏 */
@media (max-width: 400px) {
    .navbar .logo-text { font-size: 1.0625rem; }
    .nav-actions .btn-text,
    .nav-actions .btn-primary {
        padding-left: 0.5rem;
        padding-right: 0.5rem;
        font-size: 0.8125rem;
    }
    .nav-actions .lang-toggle { min-width: 40px; width: 40px; height: 44px; border-radius: 22px; }
}