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

:root {
    /* 主色调 */
    --primary: #FF6B35;
    --primary-dark: #E55A2B;
    --primary-light: #FF8A5C;
    
    /* 辅助色 */
    --dark: #1A1A2E;
    --dark-light: #16213E;
    --gray-100: #F8F9FA;
    --gray-200: #E9ECEF;
    --gray-300: #DEE2E6;
    --gray-400: #CED4DA;
    --gray-500: #ADB5BD;
    --gray-600: #6C757D;
    --gray-700: #495057;
    --gray-800: #343A40;
    --gray-900: #212529;
    
    /* 渐变 */
    --gradient-primary: linear-gradient(135deg, #FF6B35 0%, #FF8A5C 100%);
    --gradient-dark: linear-gradient(135deg, #1A1A2E 0%, #16213E 100%);
    --gradient-hero: linear-gradient(135deg, #667eea 0%, #764ba2 50%, #FF6B35 100%);
    
    /* 字体 */
    --font-sans: 'Inter', 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* 间距 */
    --spacing-xs: 0.25rem;
    --spacing-sm: 0.5rem;
    --spacing-md: 1rem;
    --spacing-lg: 1.5rem;
    --spacing-xl: 2rem;
    --spacing-2xl: 3rem;
    --spacing-3xl: 4rem;
    
    /* 圆角 */
    --radius-sm: 0.375rem;
    --radius-md: 0.5rem;
    --radius-lg: 0.75rem;
    --radius-xl: 1rem;
    --radius-2xl: 1.5rem;
    --radius-full: 9999px;
    
    /* 阴影 */
    --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
    --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
    --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-2xl: 0 25px 50px -12px rgba(0, 0, 0, 0.25);
    
    /* 过渡 */
    --transition-fast: 150ms ease;
    --transition-normal: 250ms ease;
    --transition-slow: 350ms ease;
}

html {
    scroll-behavior: smooth;
    font-size: 16px;
}

body {
    font-family: var(--font-sans);
    font-size: 1rem;
    line-height: 1.6;
    color: var(--gray-800);
    background-color: #fff;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ===== 容器 ===== */
.container {
    width: 100%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-lg);
}

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-sm);
    padding: 0.75rem 1.5rem;
    font-size: 0.9375rem;
    font-weight: 500;
    text-decoration: none;
    border: none;
    border-radius: var(--radius-lg);
    cursor: pointer;
    transition: all var(--transition-normal);
    white-space: nowrap;
}

.btn-primary {
    background: var(--gradient-primary);
    color: #fff;
    box-shadow: 0 4px 14px 0 rgba(255, 107, 53, 0.35);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px 0 rgba(255, 107, 53, 0.45);
}

.btn-outline {
    background: transparent;
    color: var(--gray-700);
    border: 2px solid var(--gray-300);
}

.btn-outline:hover {
    border-color: var(--primary);
    color: var(--primary);
    background: rgba(255, 107, 53, 0.05);
}

.btn-lg {
    padding: 1rem 2rem;
    font-size: 1rem;
}

.btn-block {
    width: 100%;
}

/* ===== 导航栏 ===== */
.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background: rgba(255, 255, 255, 0.95);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--gray-200);
    transition: all var(--transition-normal);
}

.header.scrolled {
    box-shadow: var(--shadow-md);
}

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

.logo {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    color: var(--dark);
    text-decoration: none;
    font-size: 1.25rem;
    font-weight: 700;
}

.logo-img {
    width: 36px;
    height: 36px;
    border-radius: 8px;
    object-fit: contain;
}

.logo svg {
    color: var(--primary);
}

.nav-links {
    display: flex;
    align-items: center;
    gap: var(--spacing-xl);
    list-style: none;
}

.nav-links a {
    color: var(--gray-600);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--transition-fast);
}

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

.nav-btn {
    padding: 0.625rem 1.25rem;
}

.mobile-menu-btn {
    display: none;
    background: none;
    border: none;
    color: var(--gray-700);
    cursor: pointer;
    padding: var(--spacing-sm);
}

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

.hero-bg {
    position: absolute;
    inset: 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #e4e8ec 50%, #f0f2f5 100%);
    z-index: -1;
}

.hero-bg::before {
    content: '';
    position: absolute;
    top: -50%;
    right: -20%;
    width: 80%;
    height: 150%;
    background: radial-gradient(ellipse at center, rgba(255, 107, 53, 0.08) 0%, transparent 70%);
    animation: float 20s ease-in-out infinite;
}

@keyframes float {
    0%, 100% { transform: translate(0, 0) rotate(0deg); }
    50% { transform: translate(-30px, 30px) rotate(5deg); }
}

.hero-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.hero-text {
    max-width: 560px;
}

.hero-title {
    font-size: 3.5rem;
    font-weight: 700;
    line-height: 1.2;
    color: var(--dark);
    margin-bottom: var(--spacing-lg);
}

.gradient-text {
    background: var(--gradient-primary);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.hero-desc {
    font-size: 1.125rem;
    color: var(--gray-600);
    margin-bottom: var(--spacing-xl);
    line-height: 1.7;
}

.hero-buttons {
    display: flex;
    gap: var(--spacing-md);
    flex-wrap: wrap;
}

/* 手机 Mockup */
.hero-phone {
    display: flex;
    justify-content: center;
    align-items: center;
}

.phone-mockup {
    position: relative;
    width: 280px;
    height: 560px;
    background: var(--dark);
    border-radius: 40px;
    padding: 12px;
    box-shadow: var(--shadow-2xl), 0 0 0 1px rgba(0,0,0,0.1);
    animation: phoneFloat 6s ease-in-out infinite;
}

@keyframes phoneFloat {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-15px); }
}

.phone-screen {
    width: 100%;
    height: 100%;
    background: #fff;
    border-radius: 32px;
    overflow: hidden;
    display: flex;
    flex-direction: column;
}

.phone-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 12px 20px;
    background: var(--gray-100);
    font-size: 0.75rem;
    font-weight: 600;
}

.phone-status {
    display: flex;
    gap: 4px;
}

.phone-status svg {
    color: var(--gray-700);
}

.phone-content {
    flex: 1;
    display: flex;
    flex-direction: column;
    overflow: hidden;
    background: linear-gradient(180deg, #F5FAFF 0%, #FAFCFF 100%);
}

/* 广场页面顶部Tab */
.phone-square-header {
    padding: 8px 12px 4px;
    background: rgba(255,255,255,0.9);
}

.phone-square-tabs {
    display: flex;
    gap: 4px;
}

.phone-square-tab {
    font-size: 0.6875rem;
    color: var(--gray-500);
    padding: 4px 8px;
    white-space: nowrap;
}

.phone-square-tab.active {
    color: var(--primary);
    font-weight: 600;
}

/* 广场页面子Tab */
.phone-square-subtabs {
    display: flex;
    gap: 4px;
    padding: 4px 12px 6px;
    background: #fff;
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.phone-square-subtab {
    flex: 1;
    text-align: center;
    font-size: 0.5625rem;
    color: var(--gray-500);
    padding: 6px 0;
    border-radius: 8px;
}

.phone-square-subtab.active {
    background: #FFF4E6;
    color: var(--primary);
    font-weight: 600;
}

/* 需求卡片列表 */
.phone-square-list {
    flex: 1;
    padding: 6px 8px;
    overflow: hidden;
}

.phone-demand-card {
    background: #fff;
    border-radius: 10px;
    padding: 8px;
    margin-bottom: 6px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.04);
}

.phone-demand-header {
    display: flex;
    align-items: center;
    gap: 8px;
    margin-bottom: 6px;
}

.phone-demand-avatar {
    width: 28px;
    height: 28px;
    border-radius: 8px;
    background: linear-gradient(135deg, var(--primary) 0%, var(--primary-light) 100%);
    flex-shrink: 0;
}

.phone-demand-info {
    flex: 1;
    min-width: 0;
}

.phone-demand-name {
    font-size: 0.625rem;
    font-weight: 600;
    color: var(--dark);
    margin-bottom: 2px;
}

.phone-demand-meta {
    display: flex;
    align-items: center;
    gap: 4px;
}

.phone-demand-circle {
    font-size: 0.5rem;
    color: var(--primary);
    background: #FFF3ED;
    padding: 1px 4px;
    border-radius: 4px;
}

.phone-demand-location {
    font-size: 0.5rem;
    color: var(--gray-400);
}

.phone-demand-title {
    font-size: 0.625rem;
    font-weight: 600;
    color: var(--dark);
    margin-bottom: 2px;
    line-height: 1.3;
}

.phone-demand-content {
    font-size: 0.5rem;
    color: var(--gray-500);
    line-height: 1.4;
    overflow: hidden;
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
}

/* 悬浮按钮 */
.phone-fab {
    position: absolute;
    right: 12px;
    bottom: 60px;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    background: var(--primary);
    color: #fff;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 4px 12px rgba(255, 107, 53, 0.3);
}

/* 底部导航 */
.phone-tab-bar {
    display: flex;
    justify-content: space-around;
    padding: 4px 0 6px;
    background: #fff;
    border-top: 1px solid var(--gray-200);
}

.phone-tab {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 2px;
    color: var(--gray-400);
    font-size: 0.5625rem;
}

.phone-tab.active {
    color: var(--primary);
}

.phone-tab svg {
    width: 20px;
    height: 20px;
}

.chat-bubble {
    max-width: 80%;
    padding: 10px 14px;
    border-radius: 16px;
    font-size: 0.875rem;
    line-height: 1.4;
}

.chat-bubble-left {
    background: var(--gray-100);
    color: var(--gray-800);
    align-self: flex-start;
    border-bottom-left-radius: 4px;
}

.chat-bubble-right {
    background: var(--primary);
    color: #fff;
    align-self: flex-end;
    border-bottom-right-radius: 4px;
}

.phone-input {
    padding: 12px 16px;
    background: var(--gray-100);
    color: var(--gray-500);
    font-size: 0.875rem;
}

/* ===== 功能特性 ===== */
.features {
    padding: var(--spacing-3xl) 0;
    background: #fff;
}

.section-header {
    text-align: center;
    margin-bottom: var(--spacing-3xl);
}

.section-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: var(--spacing-md);
}

.section-desc {
    font-size: 1.125rem;
    color: var(--gray-600);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: var(--spacing-xl);
}

.feature-card {
    padding: var(--spacing-xl);
    background: var(--gray-100);
    border-radius: var(--radius-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

.feature-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    background: #fff;
}

.feature-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 64px;
    height: 64px;
    background: var(--gradient-primary);
    border-radius: var(--radius-lg);
    color: #fff;
    margin-bottom: var(--spacing-lg);
}

.feature-title {
    font-size: 1.25rem;
    font-weight: 600;
    color: var(--dark);
    margin-bottom: var(--spacing-sm);
}

.feature-desc {
    font-size: 0.9375rem;
    color: var(--gray-600);
    line-height: 1.6;
}

/* ===== 下载区域 ===== */
.download {
    padding: var(--spacing-3xl) 0;
    background: var(--gradient-dark);
    color: #fff;
}

.download-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: var(--spacing-3xl);
    align-items: center;
}

.download-title {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1.3;
    margin-bottom: var(--spacing-lg);
}

.download-desc {
    font-size: 1.125rem;
    color: rgba(255, 255, 255, 0.7);
    line-height: 1.7;
}

.download-cards {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: var(--spacing-lg);
}

.download-card {
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.15);
    border-radius: var(--radius-xl);
    padding: var(--spacing-xl);
    text-align: center;
    transition: all var(--transition-normal);
}

.download-card:hover {
    background: rgba(255, 255, 255, 0.15);
    transform: translateY(-4px);
}

.download-card-icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 80px;
    height: 80px;
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-lg);
}

.download-card-icon.android {
    background: linear-gradient(135deg, #3DDC84 0%, #2ECC71 100%);
}

.download-card-icon.ios {
    background: linear-gradient(135deg, #007AFF 0%, #5856D6 100%);
}

.download-card h3 {
    font-size: 1.25rem;
    font-weight: 600;
    margin-bottom: var(--spacing-xs);
}

.download-card p {
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.6);
    margin-bottom: var(--spacing-lg);
}

/* ===== 关于我们 ===== */
.about {
    padding: var(--spacing-3xl) 0;
    background: var(--gray-100);
}

.about-content {
    text-align: center;
    max-width: 800px;
    margin: 0 auto;
}

.about-title {
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--dark);
    margin-bottom: var(--spacing-lg);
}

.about-desc {
    font-size: 1.125rem;
    color: var(--gray-600);
    line-height: 1.8;
    margin-bottom: var(--spacing-3xl);
}

.about-stats {
    display: flex;
    justify-content: center;
    gap: var(--spacing-3xl);
}

.stat-item {
    text-align: center;
}

.stat-number {
    display: block;
    font-size: 2.5rem;
    font-weight: 700;
    color: var(--primary);
    margin-bottom: var(--spacing-xs);
}

.stat-label {
    font-size: 0.9375rem;
    color: var(--gray-600);
}

/* ===== 页脚 ===== */
.footer {
    background: var(--dark);
    color: rgba(255, 255, 255, 0.7);
    padding: var(--spacing-3xl) 0 var(--spacing-xl);
}

.footer-content {
    display: grid;
    grid-template-columns: 1fr 2fr;
    gap: var(--spacing-3xl);
    margin-bottom: var(--spacing-3xl);
}

.footer-brand .logo {
    color: #fff;
    margin-bottom: var(--spacing-md);
}

.footer-brand p {
    color: rgba(255, 255, 255, 0.5);
}

.footer-links {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: var(--spacing-xl);
}

.footer-column h4 {
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: var(--spacing-lg);
}

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

.footer-column li {
    margin-bottom: var(--spacing-sm);
}

.footer-column a {
    color: rgba(255, 255, 255, 0.6);
    text-decoration: none;
    font-size: 0.9375rem;
    transition: color var(--transition-fast);
}

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

/* 联系方式标签样式 */
.footer-column .contact-label {
    color: rgba(255, 255, 255, 0.5);
    margin-right: 0.25rem;
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: var(--spacing-xl);
    text-align: center;
    font-size: 0.875rem;
    color: rgba(255, 255, 255, 0.4);
}

/* ===== 二维码弹窗 ===== */
.qr-modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    display: flex;
    align-items: center;
    justify-content: center;
    z-index: 1000;
    padding: 20px;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.qr-modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.qr-modal {
    background: #fff;
    border-radius: 16px;
    max-width: 400px;
    width: 100%;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.15);
    transform: translateY(-20px) scale(0.95);
    transition: transform 0.3s ease;
}

.qr-modal-overlay.show .qr-modal {
    transform: translateY(0) scale(1);
}

.qr-modal-header {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 24px 24px 0;
}

.qr-modal-header h3 {
    font-size: 20px;
    font-weight: 600;
    color: var(--gray-900);
    margin: 0;
}

.qr-close-btn {
    background: none;
    border: none;
    padding: 8px;
    cursor: pointer;
    border-radius: 8px;
    color: var(--gray-500);
    transition: all 0.2s ease;
}

.qr-close-btn:hover {
    background: var(--gray-100);
    color: var(--gray-700);
}

.qr-close-btn svg {
    width: 20px;
    height: 20px;
}

.qr-modal-content {
    padding: 24px;
    text-align: center;
}

.qr-code {
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
}

.qr-code canvas {
    border-radius: 12px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.qr-subtitle {
    color: var(--gray-600);
    font-size: 14px;
    margin: 0;
}

/* ===== 响应式设计 ===== */
@media (max-width: 1024px) {
    .hero-title {
        font-size: 2.75rem;
    }
    
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .download-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .download-cards {
        max-width: 500px;
        margin: 0 auto;
    }
}

@media (max-width: 768px) {
    .nav-links, .nav-btn {
        display: none;
    }
    
    .mobile-menu-btn {
        display: block;
    }
    
    .hero-content {
        grid-template-columns: 1fr;
        text-align: center;
        padding: var(--spacing-2xl) 0;
    }
    
    .hero-title {
        font-size: 2.25rem;
    }
    
    .hero-buttons {
        justify-content: center;
    }
    
    .hero-phone {
        order: -1;
    }
    
    .phone-mockup {
        width: 240px;
        height: 480px;
    }
    
    .features-grid {
        grid-template-columns: 1fr;
    }
    
    .download-cards {
        grid-template-columns: 1fr;
    }
    
    .about-stats {
        flex-direction: column;
        gap: var(--spacing-xl);
    }
    
    .footer-content {
        grid-template-columns: 1fr;
        text-align: center;
    }
    
    .footer-links {
        grid-template-columns: repeat(3, 1fr);
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 1.875rem;
    }
    
    .section-title, .download-title, .about-title {
        font-size: 1.75rem;
    }
    
    .btn-lg {
        padding: 0.875rem 1.5rem;
        font-size: 0.9375rem;
    }
    
    .footer-links {
        grid-template-columns: 1fr;
        gap: var(--spacing-lg);
    }
}