/* ========== 全局变量与重置 ========== */
:root {
    --primary-red: #ef443b;
    --text-main: #1f2937;
    --gradient-orange: linear-gradient(45deg, #ef443b, #EE8D3B);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Noto Sans', sans-serif;
    font-weight: 300;
}

body {
    color: var(--text-main);
    background: #ffffff;
    line-height: 1.5;
    overflow-x: hidden;
}

/* ========== 导航栏 (与首页保持统一) ========== */
nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 8%;
    height: 80px;
    position: fixed;
    width: 100%;
    top: 0;
    z-index: 1000;
    background: radial-gradient(circle at 10% 20%, rgba(239, 68, 68, 0.03) 0%, rgba(255, 255, 255, 1) 50%);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #f3f4f6;
}

.nav-left {
    display: flex;
    align-items: center;
}

.logo img {
    height: 30px;
    width: 158px;
}

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

.nav-links li {
    display: flex;
    align-items: center;
    gap: 4px;
    position: relative;
    margin: 0 15px;
    border-bottom: 3px solid transparent;
    transition: 0.3s;
}

.nav-links li:hover {
    border-bottom: 3px solid #FFD5D6;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-main);
    font-size: 15px;
    font-weight: 500;
}

.nav-links-svg {
    width: 12px;
    height: 12px;
}

.nav-right {
    display: flex;
    align-items: center;
}

.btn-link {
    text-decoration: none;
    color: var(--primary-red);
    padding: 10px 24px;
    border: 2px solid var(--primary-red);
    border-radius: 6px;
    font-weight: 600;
    font-size: 14px;
    margin-left: 12px;
    transition: 0.3s;
}

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

.btn-outline {
    text-decoration: none;
    color: #fff;
    background: var(--primary-red);
    padding: 11px 24px;
    border-radius: 6px;
    font-weight: 600;
    font-size: 14px;
    transition: 0.3s;
}

.btn-outline:hover {
    background: #d93833;
}

/* ========== 下载页首屏英雄区 ========== */
.dl-hero {
    padding: 180px 8% 80px;
    background: radial-gradient(circle at 90% 10%, rgba(239, 68, 68, 0.05) 0%, rgba(255, 255, 255, 1) 50%);
    text-align: center;
}

.dl-hero h1 {
    font-size: 4rem;
    font-weight: 700;
    margin-bottom: 20px;
}

.dl-hero h1 span {
    background: var(--gradient-orange);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.dl-hero p {
    font-size: 1.2rem;
    max-width: 700px;
    margin: 0 auto 40px;
    color: #4b5563;
    line-height: 1.7;
}

/* 主下载卡片 */
.main-dl-card {
    background: #fff;
    border-radius: 24px;
    padding: 50px;
    box-shadow: 0 25px 50px -12px rgba(0, 0, 0, 0.08);
    display: inline-flex;
    align-items: center;
    gap: 40px;
    border: 1px solid #f3f4f6;
    margin-bottom: 20px;
}

.os-info {
    text-align: left;
}

.os-info h3 {
    font-size: 1.8rem;
    font-weight: 700;
    margin-bottom: 8px;
}

.os-badge {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--primary-red);
    font-weight: 700;
    margin-bottom: 15px;
    font-size: 1rem;
}

.os-badge img {
    width: 32px;
}

.btn-dl-large {
    display: block;
    background: var(--primary-red);
    color: #fff;
    padding: 20px 50px;
    border-radius: 12px;
    text-decoration: none;
    font-weight: 700;
    font-size: 1.2rem;
    box-shadow: 0 10px 30px rgba(239, 68, 68, 0.3);
    transition: 0.3s;
    white-space: nowrap;
}

.btn-dl-large:hover {
    transform: translateY(-3px);
    box-shadow: 0 15px 35px rgba(239, 68, 68, 0.4);
}

/* 版本提示链接 */
.dl-hero .alt-links {
    margin-top: 20px;
    font-size: 0.9rem;
    color: #6b7280;
}

.dl-hero .alt-links a {
    color: var(--primary-red);
    text-decoration: none;
    font-weight: 500;
}

.dl-hero .alt-links a:hover {
    text-decoration: underline;
}

/* ========== 全平台下载卡片区 ========== */
.platform-grid {
    padding: 80px 8%;
    background: #fcfcfc;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 30px;
}

.platform-card {
    background: #fff;
    padding: 30px;
    border-radius: 16px;
    border: 1px solid #eee;
    text-align: center;
    transition: 0.3s;
}

.platform-card:hover {
    border-color: var(--primary-red);
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0,0,0,0.05);
}

.platform-card img {
    width: 48px;
    margin-bottom: 20px;
}

.platform-card h4 {
    font-size: 1.4rem;
    font-weight: 700;
    margin-bottom: 15px;
    color: var(--text-main);
}

.platform-card p {
    color: #4b5563;
    margin-bottom: 20px;
    font-size: 0.95rem;
    line-height: 1.6;
}

.platform-card a {
    color: var(--primary-red);
    text-decoration: none;
    font-weight: 600;
    font-size: 0.9rem;
    border-bottom: 1px solid transparent;
    transition: 0.2s;
    display: inline-block;
}

.platform-card a:hover {
    border-bottom: 1px solid var(--primary-red);
}

/* ========== 创意版块：官方下载优势 ========== */
.advantages-section {
    padding: 80px 8%;
    background: #ffffff;
    text-align: center;
}

.advantages-section h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.advantages-section h2 span {
    color: var(--primary-red);
}

.advantages-section .section-subtitle {
    max-width: 700px;
    margin: 0 auto 50px;
    color: #4b5563;
    font-size: 1.1rem;
    line-height: 1.6;
}

.advantages-grid {
    display: flex;
    gap: 30px;
    justify-content: center;
    flex-wrap: wrap;
}

.advantage-item {
    background: #f9fafb;
    padding: 35px 25px;
    border-radius: 20px;
    flex: 1 1 220px;
    max-width: 260px;
    text-align: left;
    transition: 0.3s;
}

.advantage-item:hover {
    background: #fff;
    box-shadow: 0 10px 25px rgba(0,0,0,0.05);
    transform: translateY(-3px);
}

.advantage-item .icon {
    font-size: 2rem;
    margin-bottom: 15px;
}

.advantage-item h3 {
    font-size: 1.4rem;
    margin-bottom: 10px;
    font-weight: 700;
    color: var(--text-main);
}

.advantage-item p {
    color: #4b5563;
    font-size: 0.95rem;
    line-height: 1.6;
}

/* ========== 创意版块：版本选择指引 ========== */
.version-guide {
    padding: 60px 8%;
    background: #fcfcfc;
    text-align: center;
}

.version-guide h2 {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 15px;
}

.version-guide h2 span {
    color: var(--primary-red);
}

.version-guide .section-subtitle {
    max-width: 700px;
    margin: 0 auto 50px;
    color: #4b5563;
    font-size: 1.1rem;
    line-height: 1.6;
}

.version-cards {
    display: flex;
    gap: 30px;
    justify-content: center;
    flex-wrap: wrap;
}

.version-card {
    background: #fff;
    padding: 40px 25px;
    border-radius: 16px;
    flex: 1 1 280px;
    max-width: 350px;
    border: 1px solid #eee;
    text-align: center;
    transition: 0.3s;
}

.version-card:hover {
    border-color: var(--primary-red);
    box-shadow: 0 15px 30px rgba(0,0,0,0.05);
    transform: translateY(-5px);
}

.version-card h3 {
    font-size: 1.8rem;
    margin-bottom: 20px;
    font-weight: 700;
}

.version-card p {
    color: #4b5563;
    line-height: 1.8;
    margin-bottom: 25px;
    min-height: 90px;
}

.version-card .btn-version {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 8px;
    text-decoration: none;
    font-weight: 700;
    transition: 0.3s;
}

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

.btn-version-primary:hover {
    background: #d93833;
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(239,68,68,0.25);
}

.btn-version-outline {
    background: #fff;
    color: var(--primary-red);
    border: 2px solid var(--primary-red);
}

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

.version-footnote {
    margin-top: 40px;
    font-size: 0.9rem;
    color: #9ca3af;
}

/* ========== 页脚 ========== */
footer {
    background: #111111;
    color: #ffffff;
    padding: 80px 8% 40px;
    font-family: 'Noto Sans', sans-serif;
}

.footer-container {
    display: grid;
    grid-template-columns: 1.5fr 1fr 1fr 1fr 1fr;
    gap: 40px;
}

.footer-logo-section img {
    height: 35px;
    margin-bottom: 20px;
}

.footer-logo-section p {
    color: #999;
    font-size: 14px;
    margin-bottom: 10px;
}

.footer-column h3 {
    color: var(--primary-red);
    font-size: 1.2rem;
    font-weight: 700;
    margin-bottom: 25px;
    position: relative;
    padding-bottom: 15px;
}

.footer-column h3::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: #333;
}

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

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

.footer-column ul li a {
    color: #cccccc;
    text-decoration: none;
    font-size: 14px;
    transition: 0.3s;
}

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

.footer-bottom {
    margin-top: 60px;
    padding-top: 30px;
    border-top: 1px solid #222;
    display: flex;
    justify-content: space-between;
    align-items: center;
    font-size: 12px;
    color: #666;
}

.footer-socials {
    display: flex;
    gap: 20px;
}

.footer-socials a {
    color: #666;
    text-decoration: none;
    transition: 0.3s;
}

.footer-socials a:hover {
    color: #fff;
}

/* ========== 响应式设计 ========== */
@media (max-width: 1024px) {
    .footer-container {
        grid-template-columns: 1fr 1fr;
    }
    .footer-logo-section {
        grid-column: span 2;
        text-align: center;
        margin-bottom: 40px;
    }
    .version-cards,
    .advantages-grid {
        justify-content: center;
    }
}

@media (max-width: 768px) {
    nav {
        padding: 0 4%;
    }
    .dl-hero h1 {
        font-size: 2.5rem;
    }
    .main-dl-card {
        flex-direction: column;
        padding: 30px;
        text-align: center;
    }
    .os-info {
        text-align: center;
    }
    .btn-dl-large {
        width: 100%;
    }
    .platform-grid {
        grid-template-columns: 1fr;
    }
    .advantages-section h2,
    .version-guide h2 {
        font-size: 2rem;
    }
}