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

:root {
    --primary-color: #1890ff;
    --secondary-color: #52c41a;
    --wechat-color: #07c160;
    --alipay-color: #1677ff;
    --dark-color: #001529;
    --light-color: #f0f2f5;
    --text-color: #262626;
    --text-secondary: #8c8c8c;
    --border-color: #d9d9d9;
    --success-color: #52c41a;
    --warning-color: #faad14;
    --error-color: #f5222d;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 4px 20px rgba(0, 0, 0, 0.2);
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'PingFang SC', 'Hiragino Sans GB', 'Microsoft YaHei', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background-color: #fff;
    overflow-x: hidden;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

.header {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: #fff;
    box-shadow: var(--shadow);
    z-index: 1000;
    padding: 15px 0;
}

.header .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 26px;
    font-weight: bold;
    color: var(--primary-color);
}

.logo i {
    font-size: 32px;
}

.nav {
    display: flex;
    gap: 30px;
}

.nav a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 16px;
    font-weight: 500;
    transition: color 0.3s;
}

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

.menu-btn {
    display: none;
    background: none;
    border: none;
    font-size: 24px;
    color: var(--text-color);
    cursor: pointer;
}

.mobile-menu {
    position: fixed;
    top: 70px;
    left: 0;
    right: 0;
    background: #fff;
    box-shadow: var(--shadow);
    z-index: 999;
    display: none;
    flex-direction: column;
    padding: 20px;
}

.mobile-menu.active {
    display: flex;
}

.mobile-menu a {
    text-decoration: none;
    color: var(--text-color);
    font-size: 18px;
    padding: 15px 0;
    border-bottom: 1px solid var(--border-color);
}

.hero {
    margin-top: 70px;
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: #fff;
}

.hero .container {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 60px;
    align-items: center;
}

.hero-content h1 {
    font-size: 48px;
    margin-bottom: 20px;
    font-weight: 800;
}

.hero-subtitle {
    font-size: 22px;
    margin-bottom: 40px;
    opacity: 0.95;
}

.hero-features {
    display: flex;
    gap: 20px;
    margin-bottom: 40px;
}

.feature-tag {
    display: flex;
    align-items: center;
    gap: 8px;
    background: rgba(255, 255, 255, 0.2);
    padding: 12px 20px;
    border-radius: 50px;
    backdrop-filter: blur(10px);
}

.feature-tag i {
    font-size: 20px;
}

.hero-buttons {
    display: flex;
    gap: 20px;
}

.btn {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    padding: 16px 32px;
    border-radius: 8px;
    text-decoration: none;
    font-size: 18px;
    font-weight: 600;
    transition: all 0.3s;
    border: none;
    cursor: pointer;
}

.btn-primary {
    background: #fff;
    color: var(--primary-color);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.btn-secondary {
    background: transparent;
    color: #fff;
    border: 2px solid #fff;
}

.btn-secondary:hover {
    background: #fff;
    color: var(--primary-color);
}

.btn-small {
    padding: 10px 24px;
    font-size: 16px;
    background: var(--primary-color);
    color: #fff;
}

.btn-small:hover {
    background: #096dd9;
}

.hero-animation {
    display: flex;
    justify-content: center;
    align-items: center;
}

.exchange-visual {
    display: flex;
    align-items: center;
    gap: 40px;
}

.platform-icon {
    width: 120px;
    height: 120px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 70px;
    background: #fff;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    animation: float 3s ease-in-out infinite;
}

.platform-icon.wechat {
    color: var(--wechat-color);
    animation-delay: 0s;
}

.platform-icon.alipay {
    color: var(--alipay-color);
    animation-delay: 1.5s;
}

.exchange-arrows {
    font-size: 50px;
    animation: rotate 2s linear infinite;
}

@keyframes float {
    0%, 100% {
        transform: translateY(0);
    }
    50% {
        transform: translateY(-20px);
    }
}

@keyframes rotate {
    0% {
        transform: rotate(0deg);
    }
    100% {
        transform: rotate(360deg);
    }
}

.section-header {
    text-align: center;
    margin-bottom: 60px;
}

.section-header h2 {
    font-size: 42px;
    margin-bottom: 15px;
    font-weight: 700;
}

.section-header p {
    font-size: 20px;
    color: var(--text-secondary);
}

.services {
    padding: 100px 0;
    background: var(--light-color);
}

.service-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.service-card {
    background: #fff;
    padding: 40px 30px;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: var(--shadow-lg);
}

.service-icon {
    width: 80px;
    height: 80px;
    margin: 0 auto 25px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 40px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
}

.service-card h3 {
    font-size: 24px;
    margin-bottom: 15px;
}

.service-card p {
    color: var(--text-secondary);
    font-size: 16px;
    margin-bottom: 25px;
    line-height: 1.8;
}

.card-link {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 600;
    font-size: 16px;
}

.card-link:hover {
    gap: 12px;
}

.process {
    padding: 100px 0;
    background: #fff;
}

.process-timeline {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 50px;
    position: relative;
}

.process-step {
    text-align: center;
    position: relative;
}

.step-number {
    position: absolute;
    top: -15px;
    left: 50%;
    transform: translateX(-50%);
    width: 50px;
    height: 50px;
    border-radius: 50%;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
    font-size: 24px;
    font-weight: bold;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: var(--shadow);
}

.step-icon {
    width: 100px;
    height: 100px;
    margin: 30px auto 25px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 50px;
    background: var(--light-color);
    color: var(--primary-color);
}

.process-step h3 {
    font-size: 26px;
    margin-bottom: 15px;
}

.process-step p {
    color: var(--text-secondary);
    font-size: 17px;
    line-height: 1.8;
}

.advantages {
    padding: 100px 0;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
}

.advantage-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(350px, 1fr));
    gap: 40px;
}

.advantage-item {
    display: flex;
    gap: 25px;
    background: #fff;
    padding: 35px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.advantage-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.advantage-icon {
    width: 70px;
    height: 70px;
    flex-shrink: 0;
    border-radius: 12px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 35px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
}

.advantage-item h3 {
    font-size: 22px;
    margin-bottom: 10px;
}

.advantage-item p {
    color: var(--text-secondary);
    font-size: 16px;
    line-height: 1.8;
}

.stats {
    padding: 80px 0;
    background: var(--dark-color);
    color: #fff;
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
}

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

.stat-number {
    font-size: 56px;
    font-weight: 800;
    margin-bottom: 10px;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.stat-label {
    font-size: 20px;
    color: rgba(255, 255, 255, 0.8);
}

.faq {
    padding: 100px 0;
    background: #fff;
}

.faq-list {
    max-width: 900px;
    margin: 0 auto;
}

.faq-item {
    background: #fff;
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 15px;
    overflow: hidden;
}

.faq-question {
    display: flex;
    align-items: center;
    gap: 15px;
    padding: 25px 30px;
    cursor: pointer;
    font-size: 19px;
    font-weight: 600;
    transition: background 0.3s;
}

.faq-question:hover {
    background: var(--light-color);
}

.faq-question i:first-child {
    color: var(--primary-color);
    font-size: 22px;
}

.faq-question span {
    flex: 1;
}

.faq-question i:last-child {
    transition: transform 0.3s;
}

.faq-item.active .faq-question i:last-child {
    transform: rotate(180deg);
}

.faq-answer {
    padding: 0 30px;
    max-height: 0;
    overflow: hidden;
    transition: all 0.3s;
    font-size: 17px;
    line-height: 1.8;
    color: var(--text-secondary);
}

.faq-item.active .faq-answer {
    padding: 0 30px 25px 30px;
    max-height: 500px;
}

.contact {
    padding: 100px 0;
    background: var(--light-color);
}

.contact-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 40px;
}

.contact-card {
    background: #fff;
    padding: 50px 30px;
    border-radius: 12px;
    text-align: center;
    box-shadow: var(--shadow);
}

.contact-icon {
    width: 90px;
    height: 90px;
    margin: 0 auto 25px;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 45px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: #fff;
}

.contact-card h3 {
    font-size: 26px;
    margin-bottom: 15px;
}

.contact-info {
    font-size: 20px;
    color: var(--text-secondary);
    margin-bottom: 25px;
    font-weight: 600;
}

.footer {
    background: var(--dark-color);
    color: #fff;
    padding: 60px 0 30px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-section h4 {
    font-size: 22px;
    margin-bottom: 20px;
}

.footer-section p {
    color: rgba(255, 255, 255, 0.7);
    font-size: 16px;
    line-height: 1.8;
}

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

.footer-section ul li {
    margin-bottom: 12px;
    font-size: 16px;
    color: rgba(255, 255, 255, 0.7);
}

.footer-section ul li a {
    color: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    transition: color 0.3s;
}

.footer-section ul li a:hover {
    color: #fff;
}

.footer-section ul li i {
    margin-right: 10px;
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 30px;
    text-align: center;
}

.footer-bottom p {
    font-size: 16px;
    color: rgba(255, 255, 255, 0.6);
}

.footer-bottom a {
    color: var(--primary-color);
    text-decoration: none;
}

.footer-bottom a:hover {
    text-decoration: underline;
}

.mobile-bottom-bar {
    display: none;
    position: fixed;
    bottom: 0;
    left: 0;
    right: 0;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    z-index: 1000;
    box-shadow: 0 -2px 10px rgba(0, 0, 0, 0.2);
}

.bottom-bar-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 15px 20px;
}

.bottom-bar-text {
    color: #fff;
    font-size: 18px;
    font-weight: 600;
    display: flex;
    align-items: center;
    gap: 10px;
}

.bottom-bar-text i {
    font-size: 22px;
    animation: rotate 2s linear infinite;
}

.bottom-bar-btn {
    background: #fff;
    color: var(--primary-color);
    padding: 12px 28px;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 700;
    font-size: 17px;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.2);
}

.scroll-to-top {
    position: fixed;
    bottom: 80px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: #fff;
    border-radius: 50%;
    display: none;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    cursor: pointer;
    box-shadow: var(--shadow-lg);
    transition: all 0.3s;
    z-index: 999;
}

.scroll-to-top:hover {
    background: #096dd9;
    transform: translateY(-5px);
}

.scroll-to-top.show {
    display: flex;
}

@media (max-width: 768px) {
    .nav {
        display: none;
    }

    .menu-btn {
        display: block;
    }

    .hero {
        padding: 60px 0;
    }

    .hero .container {
        grid-template-columns: 1fr;
        gap: 40px;
    }

    .hero-content h1 {
        font-size: 36px;
    }

    .hero-subtitle {
        font-size: 18px;
    }

    .hero-features {
        flex-wrap: wrap;
    }

    .feature-tag {
        font-size: 14px;
        padding: 10px 16px;
    }

    .hero-buttons {
        flex-direction: column;
    }

    .btn {
        width: 100%;
        justify-content: center;
        font-size: 17px;
    }

    .exchange-visual {
        gap: 20px;
    }

    .platform-icon {
        width: 90px;
        height: 90px;
        font-size: 50px;
    }

    .exchange-arrows {
        font-size: 35px;
    }

    .section-header h2 {
        font-size: 32px;
    }

    .section-header p {
        font-size: 17px;
    }

    .services,
    .process,
    .advantages,
    .faq,
    .contact {
        padding: 60px 0;
    }

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

    .process-timeline {
        grid-template-columns: 1fr;
    }

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

    .advantage-item {
        flex-direction: column;
        text-align: center;
    }

    .stats-grid {
        grid-template-columns: repeat(2, 1fr);
    }

    .stat-number {
        font-size: 42px;
    }

    .stat-label {
        font-size: 16px;
    }

    .faq-question {
        font-size: 17px;
        padding: 20px;
    }

    .faq-answer {
        font-size: 15px;
    }

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

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

    .mobile-bottom-bar {
        display: block;
        padding-bottom: env(safe-area-inset-bottom);
    }

    .scroll-to-top {
        bottom: 100px;
        right: 20px;
        width: 45px;
        height: 45px;
    }

    body {
        padding-bottom: 70px;
    }

    .bottom-bar-text {
        font-size: 16px;
    }

    .bottom-bar-btn {
        font-size: 15px;
        padding: 10px 24px;
    }
}

@media (max-width: 480px) {
    .logo {
        font-size: 22px;
    }

    .logo i {
        font-size: 26px;
    }

    .hero-content h1 {
        font-size: 30px;
    }

    .hero-subtitle {
        font-size: 16px;
    }

    .section-header h2 {
        font-size: 28px;
    }

    .section-header p {
        font-size: 15px;
    }

    .service-card h3 {
        font-size: 22px;
    }

    .process-step h3 {
        font-size: 22px;
    }

    .advantage-item h3 {
        font-size: 20px;
    }

    .stat-number {
        font-size: 36px;
    }

    .bottom-bar-text {
        font-size: 14px;
    }

    .bottom-bar-btn {
        font-size: 14px;
        padding: 8px 20px;
    }
}

/* 教程下拉菜单样式 */
.tutorial-dropdown {
    position: relative;
    display: inline-block;
}

.tutorial-btn {
    position: relative;
    padding-right: 50px;
}

.tutorial-btn .fa-chevron-down {
    position: absolute;
    right: 20px;
    transition: transform 0.3s;
}

.tutorial-dropdown.active .tutorial-btn .fa-chevron-down {
    transform: rotate(180deg);
}

.tutorial-menu {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: #fff;
    border-radius: 8px;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.15);
    opacity: 0;
    visibility: hidden;
    transform: translateY(-10px);
    transition: all 0.3s;
    z-index: 1100; /* 提高z-index，确保在浮窗之上 */
    margin-top: 10px;
}

.tutorial-dropdown.active .tutorial-menu {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.tutorial-option {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 15px 20px;
    text-decoration: none;
    color: var(--text-color);
    border-bottom: 1px solid var(--border-color);
    transition: all 0.3s;
}

.tutorial-option:last-child {
    border-bottom: none;
}

.tutorial-option:hover {
    background: var(--light-color);
    color: var(--primary-color);
}

.tutorial-option i {
    font-size: 20px;
    width: 24px;
    text-align: center;
}

.tutorial-option[data-type="wechat-to-alipay"] i {
    color: var(--wechat-color);
}

.tutorial-option[data-type="alipay-to-wechat"] i {
    color: var(--alipay-color);
}

/* 移动端适配 */
@media (max-width: 768px) {
    .tutorial-menu {
        position: fixed;
        top: auto;
        bottom: 80px; /* 在浮窗上方显示，留出安全距离 */
        left: 0;
        right: 0;
        border-radius: 12px 12px 0 0;
        margin-top: 0;
        transform: translateY(100%);
        z-index: 1100; /* 确保在浮窗之上 */
    }
    
    .tutorial-dropdown.active .tutorial-menu {
        transform: translateY(0);
    }
    
    .tutorial-option {
        padding: 20px;
        font-size: 18px;
    }
}