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

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&display=swap');

:root {
    /* Refined Modern Blue Palette - More Professional and Atmospheric */
    --primary-color: #0066FF;      /* Brighter, more energetic blue */
    --primary-dark: #0052CC;
    --primary-soft: #EBF3FF;
    --secondary-color: #1E293B;    /* Deep Slate for text/contrast */
    --accent-color: #38BDF8;
    
    --text-main: #0F172A;
    --text-muted: #64748B;
    --text-light: #94A3B8;
    
    --bg-white: #FFFFFF;
    --bg-soft: #F8FAFC;
    --bg-alt: #F1F5F9;
    
    --border-base: #E2E8F0;
    --border-light: #F1F5F9;
    
    /* Premium Shadows */
    --shadow-subtle: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-card: 0 10px 15px -3px rgba(0, 0, 0, 0.04), 0 4px 6px -2px rgba(0, 0, 0, 0.02);
    --shadow-elevated: 0 20px 25px -5px rgba(0, 0, 0, 0.08), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-button: 0 4px 14px 0 rgba(0, 118, 255, 0.39);
    
    /* Spacing System */
    --space-unit: 8px;
    --space-xs: 4px;
    --space-sm: 8px;
    --space-md: 16px;
    --space-lg: 24px;
    --space-xl: 32px;
    --space-2xl: 48px;
    --space-3xl: 64px;
    --space-4xl: 96px;
    --space-section: 120px;
    
    /* Radius */
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 24px;
    --radius-xl: 32px;
    --radius-full: 9999px;

    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

body {
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    line-height: 1.6;
    color: var(--text-main);
    background-color: var(--bg-white);
    font-size: 16px;
    -webkit-font-smoothing: antialiased;
    scroll-behavior: smooth;
}

.container {
    max-width: 1240px;
    margin: 0 auto;
    padding: 0 var(--space-xl);
}

/* Typography Enhancements */
h1, h2, h3, h4 {
    color: var(--secondary-color);
    line-height: 1.2;
    font-weight: 800;
}

.section-title {
    font-size: 48px;
    text-align: center;
    margin-bottom: var(--space-md);
    letter-spacing: -0.02em;
}

.section-subtitle {
    font-size: 20px;
    text-align: center;
    color: var(--text-muted);
    max-width: 700px;
    margin: 0 auto var(--space-4xl);
    font-weight: 400;
}

/* Navigation - Refined & Minimalist */
.navbar {
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: saturate(180%) blur(20px);
    border-bottom: 1px solid var(--border-base);
    position: sticky;
    top: 0;
    z-index: 1000;
    height: 72px;
    display: flex;
    align-items: center;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255, 255, 255, 0.95);
    box-shadow: var(--shadow-subtle);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo-link {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    text-decoration: none;
}

.logo-img {
    width: 36px;
    height: 36px;
    border-radius: var(--radius-sm);
}

.logo-text {
    font-size: 26px;
    font-weight: 800;
    color: var(--secondary-color);
    letter-spacing: -0.03em;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: var(--space-xl);
    align-items: center;
    margin-left: auto;
}

.nav-menu a {
    text-decoration: none;
    color: var(--text-muted);
    font-weight: 500;
    font-size: 15px;
    transition: var(--transition);
}

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

/* Language Switcher - Premium Style */
.language-switcher {
    display: flex;
    background: var(--bg-alt);
    border-radius: var(--radius-md);
    padding: 3px;
    gap: 2px;
}

.lang-btn {
    border: none;
    padding: 6px 14px;
    font-size: 13px;
    font-weight: 600;
    color: var(--text-muted);
    border-radius: 9px;
    cursor: pointer;
    background: transparent;
    transition: var(--transition);
}

.lang-btn.active {
    background: var(--bg-white);
    color: var(--primary-color);
    box-shadow: var(--shadow-subtle);
}

.lang-btn:hover:not(.active) {
    color: var(--secondary-color);
}

/* Hero Section - Atmospheric & Clean */
.hero {
    padding: var(--space-4xl) 0 var(--space-4xl);
    background: 
        radial-gradient(circle at 100% 0%, var(--primary-soft) 0%, transparent 40%),
        radial-gradient(circle at 0% 100%, #F0F7FF 0%, transparent 40%);
    overflow: hidden;
}

.hero-wrapper {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    align-items: center;
    gap: var(--space-2xl);
}

.hero-content {
    animation: fadeInUp 0.8s ease-out;
}

.hero h1 {
    font-size: 68px;
    line-height: 1.15;
    margin-bottom: var(--space-lg);
    letter-spacing: -0.04em;
    max-width: 720px;
}

.hero h1 .highlight {
    color: var(--primary-color);
    display: inline-block;
    background: linear-gradient(120deg, var(--primary-soft) 0%, var(--primary-soft) 100%);
    background-repeat: no-repeat;
    background-size: 100% 0.3em;
    background-position: 0 85%;
}

.hero h2 {
    font-size: 22px;
    font-weight: 500;
    color: var(--text-muted);
    margin-bottom: var(--space-xl);
    letter-spacing: -0.01em;
    max-width: 720px;
}

.hero-description {
    font-size: 19px;
    color: var(--text-muted);
    margin-bottom: var(--space-3xl);
    max-width: 680px;
    line-height: 1.7;
}

.hero-downloads {
    display: flex;
    align-items: center;
    gap: var(--space-xl);
}

.qr-code {
    padding: 12px;
    background: #FFFFFF;
    border-radius: 28px; /* 更圆润的边缘，贴近参考图 */
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.05);
    border: 1.5px solid #1a1a1a; /* 更加深邃、清晰的细边框 */
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.qr-code img {
    width: 86px;
    height: 86px;
    display: block;
    border-radius: 4px; /* 二维码本身的微圆角 */
}

.app-store-btn img {
    height: 64px;
    border-radius: var(--radius-md);
    transition: var(--transition);
}

.app-store-btn:hover img {
    transform: translateY(-2px);
    box-shadow: var(--shadow-button);
}

.hero-image {
    position: relative;
    animation: fadeInRight 1s ease-out;
}

.hero-image img {
    width: 100%;
    max-width: 440px;
    height: auto;
    border-radius: 48px;
    box-shadow: var(--shadow-elevated);
    border: 8px solid rgba(255, 255, 255, 0.4);
}

@keyframes fadeInUp {
    from { opacity: 0; transform: translateY(30px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeInRight {
    from { opacity: 0; transform: translateX(40px); }
    to { opacity: 1; transform: translateX(0); }
}

/* Sections Base */
.scenarios, .ai-practice, .level-test, .progress-tracking, .testimonials, .daily-free {
    padding: var(--space-section) 0;
}

/* Grid Layouts - Optimized for 6 items in Scenarios */
.scenarios-grid, .product-showcase-grid, .testimonials-grid {
    display: grid;
    gap: var(--space-xl);
}

.scenarios-grid { 
    grid-template-columns: repeat(3, 1fr);
}

.testimonials-grid { grid-template-columns: repeat(3, 1fr); }

/* Card Components */
.scenario-card, .testimonial-card {
    background: var(--bg-white);
    border: 1px solid var(--border-base);
    border-radius: var(--radius-lg);
    padding: var(--space-2xl);
    transition: var(--transition);
}

.scenario-card:hover, .testimonial-card:hover {
    border-color: var(--primary-color);
    box-shadow: var(--shadow-elevated);
    transform: translateY(-8px);
}

.scenario-icon {
    width: 64px;
    height: 64px;
    background: var(--primary-soft);
    color: var(--primary-color);
    border-radius: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    margin-bottom: var(--space-xl);
}

.scenario-card h3 {
    font-size: 22px;
    margin-bottom: var(--space-md);
    letter-spacing: -0.01em;
}

.scenario-card p {
    color: var(--text-muted);
    font-size: 15px;
    line-height: 1.6;
}

.more-scenarios {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--space-sm);
    margin-top: var(--space-3xl);
    color: var(--primary-color);
    font-weight: 600;
    cursor: pointer;
    transition: var(--transition);
}

.more-scenarios:hover {
    gap: var(--space-md);
}

/* Feature Cards - AI Practice */
.ai-practice {
    background: var(--bg-alt); /* 使用稍微深一点的灰色，让白色手机框更显眼 */
}

/* Product Showcase - Phone Mockups */
.product-showcase-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--space-xl);
    margin-top: var(--space-3xl);
    padding-bottom: var(--space-2xl);
}

.phone-mockup {
    display: flex;
    justify-content: center;
    transition: var(--transition);
}

.phone-mockup:hover {
    transform: translateY(-12px);
}

.phone-frame {
    position: relative;
    width: 250px;
    height: 520px;
    background: #ffffff;
    border-radius: 40px;
    padding: 8px;
    box-shadow: 
        0 15px 35px rgba(0, 0, 0, 0.06),
        0 5px 15px rgba(0, 0, 0, 0.04),
        inset 0 0 0 1px rgba(0, 0, 0, 0.05);
    border: 1px solid #e2e8f0;
    overflow: hidden;
}

/* 手机顶部的灵动岛模拟 - 更加精致小巧 */
.phone-frame::before {
    content: '';
    position: absolute;
    top: 15px;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 16px;
    background: #1a1a1a;
    border-radius: 20px;
    z-index: 10;
    opacity: 0.9;
}

.phone-frame img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    border-radius: 32px;
    background: #f8f9fa;
}

/* 响应式调整 */
@media (max-width: 1200px) {
    .phone-frame {
        width: 210px;
        height: 440px;
        border-radius: 32px;
    }
    .phone-frame img {
        border-radius: 26px;
    }
}

@media (max-width: 1024px) {
    .product-showcase-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: var(--space-2xl);
    }
}

@media (max-width: 640px) {
    .product-showcase-grid {
        grid-template-columns: 1fr;
    }
    .phone-frame {
        width: 260px;
        height: 540px;
    }
}

/* Level Test Section */
.cefr-chart-card {
    background: var(--bg-white);
    border-radius: var(--radius-xl);
    padding: var(--space-3xl);
    box-shadow: var(--shadow-card);
    border: 1px solid var(--border-base);
    text-align: center;
    overflow: hidden;
}

.chart-title {
    font-size: 32px;
    margin-bottom: var(--space-sm);
}

.chart-subtitle {
    color: var(--text-muted);
    margin-bottom: var(--space-3xl);
}

.chart-image {
    width: 100%;
    overflow-x: auto;
    padding: 20px 0;
    -webkit-overflow-scrolling: touch;
}

.cefr-chart-container {
    min-width: 600px;
    margin-top: var(--space-xl);
    width: 100%;
    margin-inline: auto;
    background: transparent;
    padding: 0;
}

/* Progress Tracking */
.progress-dashboard {
    background: var(--secondary-color);
    border-radius: var(--radius-xl);
    padding: var(--space-4xl);
    color: white;
}

.dashboard-placeholder {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: var(--space-4xl);
    align-items: center;
}

.dashboard-chart {
    height: 300px;
    display: flex;
    align-items: flex-end;
    gap: var(--space-md);
    padding-bottom: var(--space-xl);
    border-bottom: 2px solid rgba(255, 255, 255, 0.1);
}

.chart-bar {
    flex: 1;
    background: var(--primary-color);
    border-radius: 6px 6px 0 0;
    transition: height 1s ease-out;
}

.dashboard-stats {
    display: flex;
    flex-direction: column;
    gap: var(--space-3xl);
}

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

.stat-number {
    font-size: 56px;
    font-weight: 800;
    color: var(--primary-color);
    line-height: 1;
    margin-bottom: var(--space-xs);
}

.stat-label {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.6);
    text-transform: uppercase;
    letter-spacing: 0.1em;
}

/* Testimonials */
.testimonial-card {
    padding: var(--space-2xl);
    border-radius: var(--radius-lg);
}

.testimonial-header {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-sm);
}

.testimonial-rating {
    display: flex;
    gap: 4px;
    margin-bottom: var(--space-md);
    color: #FBBF24; /* Star Gold */
    font-size: 14px;
}

.flag { font-size: 24px; }
.username { 
    font-weight: 700;
    color: var(--secondary-color);
}

.testimonial-text {
    color: var(--text-muted);
    font-style: italic;
    line-height: 1.7;
}

/* Daily Free - CTA Section */
.daily-free {
    position: relative;
    text-align: center;
    color: white;
    padding: 160px 0;
    overflow: hidden; /* 裁剪掉外部内容 */
}

.daily-free::before {
    content: '';
    position: absolute;
    top: -10px;    /* 向上外扩，确保裁剪掉原图可能的白边 */
    left: -10px;   /* 向左外扩 */
    right: -10px;  /* 向右外扩 */
    bottom: -10px; /* 向下外扩 */
    background: linear-gradient(rgba(10, 37, 64, 0.45), rgba(10, 37, 64, 0.45)), url('背景.jpg');
    background-size: cover;
    background-position: center;
    background-repeat: no-repeat;
    background-attachment: fixed;
    z-index: 0;
    transform: scale(1.02); /* 微调放大，彻底隐藏截图边缘 */
}

.daily-free .container {
    position: relative;
    z-index: 1; /* 确保文字在背景图层之上 */
}

.daily-free .section-title {
    font-size: 56px;
    margin-bottom: var(--space-md);
    color: white;
}

.daily-free .section-subtitle {
    font-size: 20px;
    max-width: 800px;
    margin: 0 auto var(--space-2xl);
    opacity: 0.9;
    color: white;
}

.cta-section {
    margin-top: var(--space-2xl);
}

.cta-button {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 16px;
    background-color: #FFFFFF;
    color: #000000;
    padding: 22px 60px;
    border-radius: 100px;
    font-size: 24px;
    font-weight: 700;
    text-decoration: none;
    transition: all 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    border: none;
    cursor: pointer;
    white-space: nowrap;
}

.cta-button i {
    font-size: 32px;
    margin-top: -4px;
}

.cta-button span {
    letter-spacing: -0.5px;
}

.cta-button:hover {
    transform: scale(1.05);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.12);
    background-color: #FFFFFF;
}

.cta-button:active {
    transform: scale(0.98);
}

/* CEFR Chart Custom Implementation */
.cefr-chart-container {
    margin-top: var(--space-xl);
    width: 100%;
    max-width: 800px;
    margin-inline: auto;
    background: #F8FAFC;
    padding: var(--space-xl);
    border-radius: var(--radius-lg);
}

.cefr-chart {
    display: flex;
    align-items: flex-end;
    gap: 12px;
    height: 380px;
    padding-bottom: 40px;
    position: relative;
}

.cefr-bar {
    flex: 1;
    display: flex;
    flex-direction: column;
    align-items: center;
    border-radius: 12px 12px 0 0;
    position: relative;
    transition: var(--transition);
}

.cefr-bar:hover {
    transform: translateY(-5px);
    filter: brightness(1.05);
}

.cefr-bar .level-id {
    font-size: 32px;
    font-weight: 800;
    color: white;
    margin-top: 15px;
}

.cefr-bar .level-desc {
    writing-mode: vertical-rl;
    transform: rotate(180deg);
    color: rgba(255, 255, 255, 0.9);
    font-size: 14px;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    margin-top: auto;
    margin-bottom: 20px;
}

/* Level Colors & Heights */
.cefr-bar.a1 { height: 180px; background: #FF9F67; }
.cefr-bar.a2 { height: 210px; background: #FFC13D; }
.cefr-bar.b1 { height: 240px; background: #4CAF50; }
.cefr-bar.b2 { height: 270px; background: #448AFF; }
.cefr-bar.c1 { height: 300px; background: #4FC3F7; }
.cefr-bar.c2 { height: 330px; background: #7C4DFF; }

/* Footer Labels */
.cefr-footer {
    display: flex;
    gap: 8px;
    margin-top: -32px;
}

.footer-group {
    height: 32px;
    background: #CBD5E1;
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 13px;
    font-weight: 700;
    border-radius: 4px;
}

.footer-group.basic { flex: 2; background: #94A3B8; }
.footer-group.independent { flex: 2; background: #64748B; }
.footer-group.proficient { flex: 2; background: #475569; }

@media (max-width: 600px) {
    .cefr-chart { height: 280px; gap: 4px; }
    .cefr-bar .level-id { font-size: 20px; }
    .cefr-bar .level-desc { font-size: 10px; }
    .footer-group { font-size: 10px; }
}

/* Progress Tracking - Double Card Design */
.growth-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--space-xl);
    margin-top: var(--space-2xl);
}

.growth-card {
    background: #FFFFFF;
    border-radius: 40px;
    padding: var(--space-3xl);
    border: 1px solid var(--border-base);
    display: flex;
    flex-direction: column;
    gap: var(--space-2xl);
    box-shadow: var(--shadow-card);
}

.growth-card .card-text h3 {
    font-size: 24px;
    margin-bottom: var(--space-sm);
    color: var(--secondary-color);
}

.growth-card .card-text p {
    color: var(--text-muted);
    font-size: 16px;
    line-height: 1.5;
}

.visual-container {
    background: white;
    border-radius: 32px;
    padding: var(--space-2xl);
    flex-grow: 1;
    display: flex;
    position: relative;
    box-shadow: var(--shadow-card);
}

/* Left Card: Bar Chart */
.chart-visual {
    align-items: flex-end;
    justify-content: space-between;
    height: 340px;
    padding: 40px 15px 0; /* Added side padding to prevent bubble overflow */
}

.bar-group {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-end;
    height: 100%;
    flex: 1 1 0; /* Force equal width for all 7 columns */
    min-width: 0;
}

.bar {
    width: 16px;
    background: var(--primary-color);
    border-radius: 20px;
    transition: all 1s ease-out;
}

/* Opacity logic for bars based on reference image */
.bar.h20 { height: 40px; opacity: 0.3; }
.bar.h30 { height: 60px; opacity: 0.4; }
.bar.h50 { height: 100px; opacity: 0.5; }
.bar.h70 { height: 140px; opacity: 0.6; }
.bar.h80 { height: 160px; opacity: 0.7; }
.bar.h100 { height: 200px; opacity: 0.8; }
.bar.h120 { height: 240px; opacity: 1; }

.bar-val {
    width: 54px; /* Fixed width ensures perfect centering and distribution */
    font-size: 11px;
    font-weight: 700;
    color: var(--secondary-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    background: white;
    padding: 5px 0;
    border-radius: 10px;
    box-shadow: var(--shadow-subtle);
    border: 1px solid var(--border-base);
    margin-bottom: 10px;
    white-space: nowrap;
}

.bar-val small {
    font-size: 9px;
    font-weight: 400;
    color: var(--text-light);
    line-height: 1;
}

.bar-day {
    font-size: 12px;
    color: var(--text-muted);
    font-weight: 500;
    margin-top: 12px;
}

/* Right Card: App Stats */
.app-visual {
    justify-content: center;
    align-items: center;
    background: #F1F5F9;
}

.app-frame {
    background: white;
    width: 80%;
    height: 100%;
    border-radius: 24px 24px 0 0;
    border: 4px solid var(--secondary-color);
    border-bottom: none;
    padding: var(--space-xl);
    text-align: center;
    position: relative;
    overflow: hidden;
}

.app-icon {
    font-size: 40px;
    color: var(--primary-color);
    margin-bottom: var(--space-md);
}

.app-msg {
    font-size: 12px;
    color: var(--text-muted);
    margin-bottom: var(--space-xs);
}

.app-frame h4 {
    font-size: 18px;
    color: var(--secondary-color);
    line-height: 1.3;
}

.floating-stats {
    position: absolute;
    bottom: -20px;
    left: 0;
    right: 0;
        display: flex;
    justify-content: center;
    gap: var(--space-lg);
    padding: 0 var(--space-md);
}

.float-item {
    background: white;
    padding: var(--space-lg);
    border-radius: 24px;
    box-shadow: var(--shadow-elevated);
    text-align: center;
    min-width: 140px;
}

.icon-circle {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto var(--space-sm);
    font-size: 18px;
}

.icon-circle.red { background: #FEE2E2; color: #EF4444; }
.icon-circle.green { background: #DCFCE7; color: #10B981; }

.float-item .val {
    font-size: 20px;
    font-weight: 800;
    color: var(--secondary-color);
    margin-bottom: 2px;
}

.float-item .lab {
    font-size: 12px;
    color: var(--text-muted);
}

@media (max-width: 992px) {
    .growth-grid { grid-template-columns: 1fr; }
    .growth-card { padding: var(--space-xl); }
}

/* Footer - Modern & Detailed */
.footer {
    background: var(--bg-white);
    padding: var(--space-2xl) 0 var(--space-xl);
    border-top: 1px solid var(--border-base);
}

.footer-content {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr;
    gap: var(--space-4xl);
}

.footer-brand {
        max-width: 350px;
    }

.footer-logo {
    display: flex;
    align-items: center;
    gap: var(--space-md);
    margin-bottom: var(--space-md);
}

.footer-logo-img {
    width: 36px;
    height: 36px;
}

.footer-logo-text {
    font-size: 26px;
    font-weight: 800;
    color: var(--secondary-color);
}

.company-info {
    font-size: 15px;
    color: var(--text-muted);
    line-height: 1.6;
}

.footer-app-store {
    display: inline-flex;
    align-items: center;
    gap: var(--space-lg);
    background: var(--secondary-color);
    color: white;
    padding: 12px 24px;
    border-radius: var(--radius-md);
    text-decoration: none;
    margin-top: var(--space-lg);
    transition: var(--transition);
}

.footer-app-store i {
    font-size: 24px;
}

.footer-app-store span {
    display: flex;
    flex-direction: column;
    align-items: flex-start;
    line-height: 1.1;
}

.footer-app-store small {
    font-size: 11px;
    opacity: 0.8;
}

.footer-app-store strong {
        font-size: 16px;
    font-weight: 700;
    }

.footer-app-store:hover {
    background: #000;
    transform: translateY(-2px);
    }

.footer-column h4 {
        font-size: 26px;
    margin-bottom: var(--space-lg);
    color: var(--secondary-color);
    font-weight: 800;
}

.footer-column ul {
    list-style: none;
}

.footer-column li {
    margin-bottom: 4px; /* 调整间距，使其与左侧文字行高视觉一致 */
}

.footer-column a {
    color: var(--text-muted);
    text-decoration: none;
        font-size: 16px;
    transition: var(--transition);
    display: inline-block;
    position: relative;
}

.footer-column a:hover {
    color: var(--primary-color);
    transform: translateX(4px); /* 悬增加微小的向右位移，增强交互感 */
}

.footer-column a::after {
    content: '';
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background: var(--primary-color);
    transition: var(--transition);
}

.footer-column a:hover::after {
    width: 100%; /* 悬浮时下划线展开 */
    }

    .footer-social {
    display: flex;
    gap: var(--space-lg);
    margin-top: var(--space-lg);
    align-items: center;
}

.social-logo {
    display: block;
    width: 28px;
    height: 28px;
    transition: var(--transition);
}

.social-logo img {
    width: 100%;
    height: 100%;
    object-fit: contain;
}

.social-logo:hover {
    transform: translateY(-3px) scale(1.1);
}

/* Responsive Overrides */
@media (max-width: 1024px) {
    .hero h1 { font-size: 56px; }
    .hero-wrapper { gap: var(--space-2xl); }
    .scenarios-grid, .testimonials-grid { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
    :root { --space-section: 80px; }
    
    .navbar { height: 64px; }
    
    .nav-menu {
        position: fixed;
        top: 64px;
        left: -100%;
        width: 100%;
        height: calc(100vh - 64px);
        background: var(--bg-white);
        flex-direction: column;
        padding: var(--space-4xl) 0;
        transition: var(--transition);
    }
    
    .nav-menu.active { left: 0; }
    
    .nav-toggle {
        display: flex;
        flex-direction: column;
        gap: 6px;
        cursor: pointer;
    }
    
    .nav-toggle span {
        width: 28px;
        height: 2px;
        background: var(--secondary-color);
        transition: var(--transition);
    }
    
    .hero-wrapper {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .hero h1 { font-size: 40px; }
    .hero-description { margin-inline: auto; }
    .hero-downloads { justify-content: center; }
    
    .dashboard-placeholder { grid-template-columns: 1fr; }
    
    .scenarios-grid, .testimonials-grid { grid-template-columns: 1fr; }
    
    .footer-content { grid-template-columns: 1fr; }
}

@media (max-width: 480px) {
    .hero h1 { font-size: 32px; }
    .hero-downloads { flex-direction: column; }
    .section-title { font-size: 32px; }
}