/* 基础样式 */
:root {
    --primary-color: #4a6fa5;
    --secondary-color: #1a3f75; /* #166088 */
    --accent-color: #4cb5ae;
    --light-color: #f8f9fa;
    --dark-color: #333;
    --gray-color: #6c757d;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    line-height: 1.6;
    color: var(--dark-color);
    background-color: var(--light-color);
}

.container {
    width: 90%;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 15px;
}

.btn {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 0.8rem 1.5rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
    transition: var(--transition);
}

.btn:hover {
    background: var(--secondary-color);
    transform: translateY(-3px);
}

section {
    padding: 5rem 0;
}

.section-title {
    text-align: center;
    margin-bottom: 3rem;
}

.section-title h2 {
    font-size: 2.5rem;
    color: var(--dark-color);
    margin-bottom: 1rem;
    position: relative;
}

.section-title h2::after {
    content: '';
    position: absolute;
    bottom: -10px;
    left: 50%;
    transform: translateX(-50%);
    width: 70px;
    height: 3px;
    background: var(--primary-color);
}

.section-title p {
    color: var(--gray-color);
    max-width: 700px;
    margin: 0 auto;
    padding-top: 1rem;
}

/* 导航栏样式 */
header {
    background-color: white;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 1000;
}

.navbar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 0;
}

.logo {
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--primary-color);
    display: flex;
    align-items: center;
}

.logo i {
    margin-right: 10px;
}

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

.nav-links li {
    margin-left: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--dark-color);
    font-weight: 500;
    transition: var(--transition);
    position: relative;
}

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

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 2px;
    background: var(--primary-color);
    transition: var(--transition);
}

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

.menu-toggle {
    display: none;
    cursor: pointer;
    font-size: 1.5rem;
}

/* 英雄区域样式 */
.hero {
    padding: 5rem 0;
    background: linear-gradient(rgba(0, 0, 0, 0), rgba(248, 249, 250, 255)), url('../images/hero-bg.jpg') no-repeat center center/cover;
    color: white;
    text-align: center;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.5);
}

.hero p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto 2rem;
    text-shadow: 1px 1px 2px rgba(0, 0, 0, 0.5);
}

/* 服务区域样式 */
.services-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.service-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.service-card:hover {
    transform: translateY(-10px);
    box-shadow: 0 15px 30px rgba(0, 0, 0, 0.1);
}

.service-icon {
    font-size: 3rem;
    color: var(--primary-color);
    margin-bottom: 1.5rem;
}

.service-card h3 {
    margin-bottom: 1rem;
    color: var(--dark-color);
}

.service-card p {
    color: var(--gray-color);
}

/* 关于区域样式 */
.about-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: center;
}

.about-image img {
    width: 100%;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.about-text h3 {
    font-size: 1.8rem;
    margin-bottom: 1.5rem;
    color: var(--dark-color);
}

.about-text p {
    margin-bottom: 1.5rem;
    color: var(--gray-color);
}

/* 下载区域样式 */
.dl-card {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: var(--transition);
}

.dl-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 7px 15px rgba(0, 0, 0, 0.1);
}

.download {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 2rem;
}

@media (max-width: 710px) {
    .download {
        grid-template-columns: repeat(1, 1fr);
    }
}

.dl-on {
    display: grid;
    grid-template-columns: repeat(1, 1fr);
    gap: 2rem;
    vertical-align:bottom;
}

@media (max-width: 710px) {
    .dl-on {
        grid-template-columns: repeat(2, 1fr);
    }
}

.dl-in {
    display: grid;
    grid-template-columns: repeat(1, 1fr);
    gap: 0.5rem;
    vertical-align:bottom;
}

.dl-btn {
    display: inline-block;
    background: #f0f0f0;
    color: black;
    padding: 0.8rem 1.5rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    text-decoration: none;
    font-size: 1rem;
    transition: var(--transition);
}

.dl-btn:hover {
    background: #c0c0c0;
    transform: translateY(-3px);
}

.dl-img {
    height: 100px;
}

/* 联系区域样式 */
.contact-form {
    max-width: 700px;
    margin: 0 auto;
    background: white;
    padding: 3rem;
    border-radius: 8px;
    box-shadow: var(--shadow);
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;
    margin-bottom: 0.5rem;
    font-weight: 500;
    color: var(--dark-color);
}

.form-control {
    width: 100%;
    padding: 0.8rem 1rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 1rem;
    transition: var(--transition);
}

.form-control:focus {
    border-color: var(--primary-color);
    outline: none;
    box-shadow: 0 0 0 2px rgba(74, 111, 165, 0.2);
}

textarea.form-control {
    min-height: 150px;
    resize: vertical;
}

/* 页脚样式 */
footer {
    background: var(--dark-color);
    color: white;
    padding: 3rem 0 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    margin-bottom: 2rem;
}

.footer-column h3 {
    font-size: 1.3rem;
    margin-bottom: 1.5rem;
    position: relative;
    padding-bottom: 10px;
}

.footer-column h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 40px;
    height: 2px;
    background: var(--accent-color);
}

.footer-links {
    list-style: none;
}

.footer-links li {
    margin-bottom: 0.8rem;
}

.footer-links a {
    color: #bbb;
    text-decoration: none;
    transition: var(--transition);
}

.footer-links a:hover {
    color: white;
}

.social-links {
    display: flex;
    gap: 1rem;
    margin-top: 1rem;
}

.social-links a {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 40px;
    height: 40px;
    background: #444;
    color: white;
    border-radius: 50%;
    text-decoration: none;
    transition: var(--transition);
}

.social-links a:hover {
    background: var(--accent-color);
    color: var(--dark-color);
    transform: translateY(-3px);
}

.copyright {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #444;
    color: #bbb;
    font-size: 0.9rem;
}