/* 基础设置 */
:root {
    --primary-color: #276EF1; /* 钉钉蓝 */
    --primary-light: #4c89f5;
    --primary-dark: #1e5ad1;
    --bg-gray: #f8fafc;
    --text-dark: #1e293b;
    --text-light: #64748b;
    --white: #ffffff;
    --radius: 12px;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --container-width: 1200px;
}

@keyframes gradientFlow {
    0% { background-position: 0% 50%; }
    50% { background-position: 100% 50%; }
    100% { background-position: 0% 50%; }
}

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

body {
    font-family: "Inter", "PingFang SC", "Microsoft YaHei", sans-serif;
    line-height: 1.6;
    color: var(--text-dark);
    background-color: var(--white);
    overflow-x: hidden;
    /* 应用背景底图并切掉底部水印 */
    background-image: url('../assets/背景底图.png');
    background-attachment: fixed;
    background-size: 100% 115%; /* 进一步拉伸高度以确保切掉更多底部 */
    background-position: center top; /* 靠顶对齐 */
    background-repeat: no-repeat;
}

/* 简化背景 */
body::before {
    content: "";
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(to bottom, rgba(255, 255, 255, 0.1), rgba(255, 255, 255, 0.2));
    z-index: -1;
    pointer-events: none;
}

a {
    text-decoration: none;
    color: inherit;
    transition: all 0.3s ease;
}

ul {
    list-style: none;
}

img {
    max-width: 100%;
}

.container {
    max-width: var(--container-width);
    margin: 0 auto;
    padding: 0 20px;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 10px 24px;
    border-radius: 6px;
    font-size: 14px;
    font-weight: 600;
    cursor: pointer;
    border: none;
    text-align: center;
    transition: all 0.3s ease;
}

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

.btn-primary:hover {
    background-color: var(--primary-dark);
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(39, 110, 241, 0.3);
}

.btn-outline {
    background-color: transparent;
    border: 1px solid var(--primary-color);
    color: var(--primary-color);
}

.btn-outline:hover {
    background-color: rgba(39, 110, 241, 0.05);
}

.btn-large {
    padding: 14px 36px;
    font-size: 16px;
}

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

.btn-white:hover {
    background-color: #f8f9fa;
    transform: translateY(-2px);
}

/* 导航栏 */
.header {
    height: 72px;
    background-color: rgba(255, 255, 255, 0.9);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #edf2f7;
    position: sticky;
    top: 0;
    z-index: 1000;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 12px;
}

.logo-img {
    height: 32px;
}

.app-name {
    font-size: 20px;
    font-weight: 700;
    color: var(--primary-color);
}

.nav ul {
    display: flex;
    gap: 32px;
}

.nav a {
    font-size: 15px;
    font-weight: 500;
    color: var(--text-dark);
}

.nav a.active {
    color: var(--primary-color);
    font-weight: 700;
}

.nav a.active::after {
    content: "";
    display: block;
    width: 100%;
    height: 2px;
    background: var(--primary-color);
    margin-top: 4px;
    border-radius: 2px;
}

.header-btns {
    display: flex;
    gap: 12px;
}

.mobile-menu-btn {
    display: none;
}

/* Hero 区 */
.hero {
    background: linear-gradient(135deg, rgba(30, 90, 209, 0.8), rgba(39, 110, 241, 0.7), rgba(76, 137, 245, 0.6));
    background-size: 200% 200%;
    animation: gradientFlow 10s ease infinite;
    color: var(--white);
    padding: 120px 0;
    overflow: hidden;
    backdrop-filter: blur(10px);
}

.hero-container {
    display: flex;
    flex-direction: column; /* 改为垂直排版 */
    align-items: center;
    justify-content: center;
    text-align: center; /* 居中对齐 */
    gap: 40px;
}

.hero-text {
    flex: 1;
    width: 100%;
    max-width: 800px; /* 限制宽度以保持美感 */
}

.hero-title {
    font-size: 56px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 24px;
}

.hero-subtitle {
    font-size: 22px; /* 稍微调大字体 */
    margin-bottom: 40px;
    opacity: 0.95;
}

.hero-cta {
    display: flex;
    justify-content: center; /* 按钮居中 */
    gap: 20px;
    margin-bottom: 48px;
}

.hero-tags {
    display: flex;
    justify-content: center; /* 标签居中 */
    gap: 24px;
    font-size: 14px;
}

.hero-tags span {
    display: flex;
    align-items: center;
    gap: 8px;
}

.hero-image-box {
    width: 100%;
    max-width: 900px; /* 限制大图宽度 */
    perspective: 1000px;
}

.hero-img-actual {
    width: 100%;
    border-radius: var(--radius);
    box-shadow: 0 30px 60px rgba(0, 0, 0, 0.25); /* 增加阴影感 */
    border: 1px solid rgba(255, 255, 255, 0.1);
    transition: transform 0.15s cubic-bezier(0.23, 1, 0.32, 1);
    will-change: transform;
    position: relative;
}

/* 通用章节 */
.section {
    padding: 100px 0;
}

.section-gray {
    background-color: rgba(248, 250, 252, 0.6); /* 增加透明度以透出背景图 */
    backdrop-filter: blur(5px);
}

.section-title {
    text-align: center;
    font-size: 36px;
    font-weight: 800;
    margin-bottom: 64px;
    color: var(--text-dark);
}

/* 卡片 */
.grid {
    display: grid;
    gap: 32px;
    justify-content: center; /* 确保 grid 整体居中 */
}

.grid-3 { grid-template-columns: repeat(3, 1fr); }
.grid-5 { grid-template-columns: repeat(5, 1fr); }
.grid-2 { grid-template-columns: repeat(2, 1fr); }
.grid-4 { grid-template-columns: repeat(4, 1fr); }

/* 针对居中排版的微调 */
.section-title {
    text-align: center;
    font-size: 42px; /* 增大标题 */
    font-weight: 800;
    margin-bottom: 72px;
    color: var(--text-dark);
    position: relative;
}

.section-title::after {
    content: "";
    display: block;
    width: 60px;
    height: 4px;
    background: var(--primary-color);
    margin: 16px auto 0;
    border-radius: 2px;
}

.card {
    background: var(--white);
    padding: 40px 32px;
    border-radius: var(--radius);
    border: 1px solid #edf2f7;
    transition: all 0.3s ease;
    text-align: center; /* 卡片内容居中 */
}

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

/* 功能模块 */
.feature-list {
    display: flex;
    flex-direction: column;
    gap: 120px;
}

.feature-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 48px;
    width: 100%;
}

.feature-content {
    width: 100%;
    max-width: 800px;
}

.feature-content h3 {
    font-size: 42px;
    font-weight: 800;
    margin-bottom: 24px;
    justify-content: center;
    display: flex;
    align-items: center;
    gap: 16px;
}

.badge {
    background: rgba(39, 110, 241, 0.1);
    color: var(--primary-color);
    padding: 6px 16px;
    border-radius: 20px;
    font-size: 14px;
}

.feature-content p {
    font-size: 20px;
    color: var(--text-light);
    line-height: 1.8;
}

.feature-image {
    width: 100%;
    max-width: 900px;
    perspective: 1000px;
}

.feature-img-actual {
    width: 100%;
    border-radius: var(--radius);
    box-shadow: 0 20px 50px rgba(0, 0, 0, 0.1);
    border: 1px solid rgba(226, 232, 240, 0.5);
    transition: transform 0.15s cubic-bezier(0.23, 1, 0.32, 1);
    will-change: transform;
    position: relative;
}

/* 优势模块 */
.adv-item {
    text-align: center;
}

.adv-icon {
    width: 64px;
    height: 64px;
    background: rgba(39, 110, 241, 0.1);
    color: var(--primary-color);
    font-size: 24px;
    font-weight: 800;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

/* 安装步骤 */
.section-blue {
    background-color: var(--primary-color);
    color: var(--white);
    text-align: center;
}

.section-blue .section-title {
    color: var(--white);
}

.section-blue .section-title::after {
    background: var(--white);
}

.step-item {
    padding: 24px;
}

.step-num {
    font-size: 48px;
    font-weight: 800;
    opacity: 0.3;
    margin-bottom: 12px;
}

.step-tip {
    margin-top: 40px;
    opacity: 0.8;
}

/* FAQ */
.faq-list {
    max-width: 800px;
    margin: 0 auto;
}

.faq-item {
    background: var(--white);
    padding: 24px;
    border-radius: var(--radius);
    margin-bottom: 20px;
    border: 1px solid #edf2f7;
}

.faq-question {
    font-weight: 700;
    color: var(--primary-color);
    margin-bottom: 8px;
}

/* Footer */
.footer {
    background-color: #0f172a;
    color: var(--white);
    padding: 100px 0 60px;
    text-align: center;
}

.footer-top {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 64px;
    margin-bottom: 80px;
}

.footer-info h3 {
    font-size: 28px;
    margin-bottom: 12px;
}

.footer-info p {
    opacity: 0.7;
    font-size: 18px;
}

.footer-links-grid {
    display: flex;
    justify-content: center;
    gap: 80px;
    flex-wrap: wrap;
}

.footer h4 {
    margin-bottom: 24px;
    font-size: 18px;
    color: var(--primary-light);
}

.footer ul li {
    margin-bottom: 12px;
    opacity: 0.7;
}

.footer ul li a:hover {
    color: var(--primary-light);
    opacity: 1;
}

.footer-action {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.qr-code {
    width: 160px;
    height: 160px;
    background: var(--white);
    padding: 12px;
    border-radius: 12px;
    margin-bottom: 24px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
}

.qr-code img {
    width: 100%;
    height: 100%;
    display: block;
    object-fit: contain;
}

.footer-bottom {
    text-align: center;
    padding-top: 40px;
    border-top: 1px solid rgba(255, 255, 255, 0.05);
    opacity: 0.4;
    font-size: 14px;
}

/* 响应式 */
@media (max-width: 992px) {
    .hero-title {
        font-size: 40px;
    }
    .hero-subtitle {
        font-size: 18px;
    }
    .grid-3, .grid-5, .grid-4, .grid-2 {
        grid-template-columns: 1fr;
    }
    .feature-content h3 {
        font-size: 28px;
    }
    .footer-links-grid {
        gap: 40px;
    }
}