/* ===== 全局变量与重置 ===== */
:root {
    --primary: #2563eb;
    --primary-dark: #1d4ed8;
    --primary-light: #3b82f6;
    --secondary: #8b5cf6;
    --dark: #0f172a;
    --gray: #64748b;
    --light-gray: #f1f5f9;
    --white: #ffffff;
    --shadow-sm: 0 1px 3px rgba(0,0,0,0.1);
    --shadow-md: 0 4px 6px -1px rgba(0,0,0,0.1);
    --shadow-lg: 0 10px 15px -3px rgba(0,0,0,0.1);
    --transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

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

html {
    font-size: 16px;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', sans-serif;
    line-height: 1.6;
    color: var(--dark);
    background: var(--white);
    overflow-x: hidden;
}

/* 容器通用样式 */
.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 24px;
}

/* 移除所有默认下划线，并优化链接样式 */
a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

a:not(.btn):hover {
    color: var(--primary);
}

/* 按钮重置下划线 */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 40px;
    font-weight: 600;
    font-size: 1rem;
    transition: var(--transition);
    cursor: pointer;
    border: none;
    background: none;
}

.btn.primary {
    background: var(--primary);
    color: var(--white);
    box-shadow: var(--shadow-sm);
}

.btn.primary:hover {
    background: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
    color: var(--white);
}

.btn.secondary {
    background: transparent;
    border: 2px solid var(--primary);
    color: var(--primary);
}

.btn.secondary:hover {
    background: var(--primary);
    color: var(--white);
    transform: translateY(-2px);
}

/* 导航栏 */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    z-index: 1000;
    transition: var(--transition);
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.nav-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 72px;
    padding: 0 32px;
    max-width: 1400px;
    margin: 0 auto;
}

.logo a {
    font-size: 1.75rem;
    font-weight: 800;
    background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
    letter-spacing: -0.5px;
}

.logo span {
    font-weight: 500;
    font-size: 0.9rem;
    background: none;
    -webkit-background-clip: unset;
    background-clip: unset;
    color: var(--gray);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 36px;
}

.nav-links a {
    font-weight: 500;
    color: var(--dark);
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -6px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s ease;
}

.nav-links a:hover::after,
.nav-links a.active::after {
    width: 100%;
}

.menu-btn {
    display: none;
    font-size: 1.5rem;
    cursor: pointer;
    color: var(--dark);
}

/* 移动端导航 */
@media (max-width: 768px) {
    .menu-btn {
        display: block;
    }
    .nav-links {
        position: absolute;
        top: 72px;
        left: 0;
        width: 100%;
        background: var(--white);
        flex-direction: column;
        gap: 0;
        max-height: 0;
        overflow: hidden;
        transition: max-height 0.4s ease;
        box-shadow: var(--shadow-md);
        border-top: 1px solid #eef2ff;
    }
    .nav-links.active {
        max-height: 320px;
    }
    .nav-links li {
        width: 100%;
        text-align: center;
    }
    .nav-links a {
        display: block;
        padding: 16px 20px;
        border-bottom: 1px solid #f0f0f0;
    }
    .nav-links a::after {
        display: none;
    }
}

/* Hero 区域 */
.hero {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    background: linear-gradient(145deg, #f8fafc 0%, #eef2ff 100%);
    position: relative;
    padding: 100px 20px 60px;
}

.hero-content {
    max-width: 900px;
    z-index: 2;
}

.hero h1 {
    font-size: 3.2rem;
    font-weight: 800;
    margin-bottom: 20px;
    line-height: 1.2;
}

.highlight {
    color: var(--primary);
    position: relative;
    display: inline-block;
}

.hero p {
    font-size: 1.3rem;
    color: var(--gray);
    margin-bottom: 24px;
}

.invite-code {
    background: rgba(37, 99, 235, 0.08);
    display: inline-flex;
    align-items: baseline;
    gap: 8px;
    padding: 10px 20px;
    border-radius: 60px;
    margin: 20px 0 16px;
    backdrop-filter: blur(4px);
    cursor: pointer;
    transition: var(--transition);
}

.invite-code:hover {
    background: rgba(37, 99, 235, 0.15);
    transform: scale(1.02);
}

.code-label {
    font-weight: 500;
    color: var(--gray);
}

.code-number {
    font-size: 1.4rem;
    font-weight: 800;
    color: var(--primary);
    letter-spacing: 1px;
}

.copy-tip {
    font-size: 0.75rem;
    color: var(--gray);
    background: rgba(0,0,0,0.05);
    padding: 2px 8px;
    border-radius: 30px;
}

.cta-buttons {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
    margin-top: 16px;
}

.scroll-indicator {
    position: absolute;
    bottom: 32px;
    left: 50%;
    transform: translateX(-50%);
}

.mouse {
    width: 28px;
    height: 46px;
    border: 2px solid var(--gray);
    border-radius: 20px;
    position: relative;
}

.mouse::before {
    content: '';
    width: 4px;
    height: 8px;
    background: var(--primary);
    position: absolute;
    left: 50%;
    transform: translateX(-50%);
    top: 10px;
    border-radius: 2px;
    animation: scrollMove 1.8s infinite;
}

@keyframes scrollMove {
    0% { opacity: 1; transform: translateX(-50%) translateY(0);}
    100% { opacity: 0; transform: translateX(-50%) translateY(16px);}
}

/* 通用区块样式 */
section {
    padding: 80px 0;
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 48px;
    position: relative;
}

.section-title:after {
    content: '';
    display: block;
    width: 70px;
    height: 4px;
    background: var(--primary);
    margin: 16px auto 0;
    border-radius: 4px;
}

/* About - 恢复淡蓝色背景 */
.about {
    background: #eef2ff;  /* 淡蓝色背景，与 hero 区域呼应 */
}

.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 50px;
    align-items: center;
}

.about-text p {
    color: var(--gray);
    margin-bottom: 20px;
    line-height: 1.7;
}

.video-wrapper {
    margin-top: 24px;
    border-radius: 20px;
    overflow: hidden;
    box-shadow: var(--shadow-md);
}

.about-stats {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 24px;
}

.stat-item {
    background: var(--white);
    padding: 28px 16px;
    border-radius: 28px;
    text-align: center;
    transition: var(--transition);
    box-shadow: var(--shadow-sm);
}

.stat-item:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-lg);
}

.stat-item .number {
    font-size: 2.4rem;
    font-weight: 800;
    color: var(--primary);
    display: block;
}

.stat-item .label {
    color: var(--gray);
    margin-top: 8px;
}

/* 店铺展示 iframe */
.projects {
    background: var(--white);
}

.iframe-container {
    width: 100%;
    border-radius: 24px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
    background: #f9f9ff;
}

.iframe-container iframe {
    width: 100%;
    height: 700px;
    border: none;
    display: block;
}

/* APP下载区 */
.app-download {
    background: linear-gradient(120deg, #f0f9ff 0%, #e9f0ff 100%);
}

.app-showcase {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 32px;
}

.app-image img {
    max-width: 280px;
    border-radius: 36px;
    box-shadow: var(--shadow-lg);
    transition: transform 0.3s;
}

.app-image img:hover {
    transform: scale(1.02);
}

.download-buttons {
    display: flex;
    gap: 24px;
    flex-wrap: wrap;
    justify-content: center;
}

.download-btn {
    display: inline-flex;
    align-items: center;
    gap: 12px;
    padding: 14px 32px;
    border-radius: 60px;
    font-weight: 600;
    transition: var(--transition);
    background: var(--dark);
    color: white;
    font-size: 1.1rem;
}

.download-btn.android {
    background: #3ddc84;
    color: #1a1a1a;
}

.download-btn.ios {
    background: #000;
}

.download-btn:hover {
    transform: translateY(-4px);
    filter: brightness(0.95);
    color: white;
}

/* 联系我们 */
.contact {
    background: var(--white);
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 48px;
}

.contact-info {
    background: var(--light-gray);
    padding: 32px;
    border-radius: 32px;
}

.info-item {
    display: flex;
    align-items: center;
    gap: 18px;
    margin-bottom: 28px;
    padding: 8px 0;
}

.info-item i {
    width: 48px;
    height: 48px;
    background: rgba(37, 99, 235, 0.12);
    display: flex;
    align-items: center;
    justify-content: center;
    border-radius: 60px;
    font-size: 1.4rem;
    color: var(--primary);
}

.info-text h4 {
    font-weight: 700;
    margin-bottom: 4px;
}

.info-text p a {
    color: var(--gray);
    transition: color 0.2s;
}

.info-text p a:hover {
    color: var(--primary);
}

.contact-form-wrapper {
    background: var(--white);
    border-radius: 32px;
    box-shadow: var(--shadow-lg);
    padding: 32px;
    border: 1px solid #eef2ff;
}

.simple-contact h3 {
    font-size: 1.6rem;
    margin-bottom: 24px;
    color: var(--dark);
}

.form-field {
    margin-bottom: 20px;
}

.form-field input,
.form-field textarea {
    width: 100%;
    padding: 14px 18px;
    border: 1.5px solid #e2e8f0;
    border-radius: 24px;
    font-size: 1rem;
    transition: var(--transition);
    font-family: inherit;
}

.form-field input:focus,
.form-field textarea:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.2);
}

.submit-btn {
    width: 100%;
    margin-top: 8px;
}

.form-note {
    font-size: 0.8rem;
    color: var(--gray);
    text-align: center;
    margin-top: 16px;
}

/* 页脚 */
.footer {
    background: var(--dark);
    color: #cbd5e1;
    padding: 48px 0 32px;
    text-align: center;
}

.social-links {
    display: flex;
    justify-content: center;
    gap: 28px;
    margin-bottom: 28px;
}

.social-links a {
    color: #cbd5e1;
    font-size: 1.6rem;
    transition: var(--transition);
}

.social-links a:hover {
    color: var(--primary-light);
    transform: translateY(-3px);
}

.footer-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 18px;
    margin-bottom: 28px;
}

.footer-links a {
    color: #94a3b8;
    font-size: 0.9rem;
    transition: color 0.2s;
}

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

.footer p {
    font-size: 0.85rem;
    margin-top: 12px;
}

/* 返回顶部 */
#back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    background: var(--primary);
    color: white;
    border-radius: 60px;
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    opacity: 0;
    visibility: hidden;
    transition: var(--transition);
    box-shadow: var(--shadow-md);
    z-index: 99;
}

#back-to-top.show {
    opacity: 1;
    visibility: visible;
}

#back-to-top:hover {
    background: var(--primary-dark);
    transform: translateY(-4px);
}

/* 响应式 */
@media (max-width: 992px) {
    .about-content, .contact-content {
        grid-template-columns: 1fr;
        gap: 40px;
    }
    .hero h1 {
        font-size: 2.4rem;
    }
    .hero p {
        font-size: 1.1rem;
    }
}

@media (max-width: 640px) {
    .section-title {
        font-size: 2rem;
    }
    .about-stats {
        grid-template-columns: 1fr;
    }
    .iframe-container iframe {
        height: 500px;
    }
    .btn {
        padding: 10px 22px;
    }
    .invite-code {
        flex-wrap: wrap;
        justify-content: center;
    }
}

/* 滚动动画通用 */
.animate-text {
    opacity: 0;
    transform: translateY(20px);
    animation: fadeUp 0.6s forwards;
}

@keyframes fadeUp {
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.hero h1 { animation-delay: 0.1s; }
.hero p:first-of-type { animation-delay: 0.2s; }
.invite-code { animation-delay: 0.35s; }
.cta-buttons { animation-delay: 0.5s; }

/* QQ浏览器兼容性修复 */
html {
    scroll-behavior: smooth;
}

/* 确保点击区域可点击 */
.nav-links a, .btn.secondary, .logo a {
    cursor: pointer;
}