/* ===== 全局样式 ===== */
:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --secondary: #8b5cf6;
    --accent: #06b6d4;
    --gradient: linear-gradient(135deg, #6366f1, #8b5cf6, #06b6d4);
    --bg-color: #f8fafc;
    --card-bg: #ffffff;
    --text-primary: #1e293b;
    --text-secondary: #64748b;
    --text-light: #94a3b8;
    --border-color: #e2e8f0;
    --shadow: 0 4px 20px rgba(0,0,0,0.08);
    --shadow-hover: 0 8px 30px rgba(99,102,241,0.15);
    --radius: 16px;
    --radius-sm: 8px;
    --transition: all 0.3s ease;
}

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

html {
    scroll-behavior: smooth;
}

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

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 24px;
}

a {
    text-decoration: none;
    color: inherit;
    transition: var(--transition);
}

img {
    max-width: 100%;
    height: auto;
}

ul {
    list-style: none;
}

/* ===== 按钮 ===== */
.btn {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 12px 28px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 16px;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
}

.btn-primary {
    background: var(--gradient);
    color: #fff;
    box-shadow: 0 4px 15px rgba(99,102,241,0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 25px rgba(99,102,241,0.4);
}

.btn-secondary {
    background: rgba(255,255,255,0.15);
    color: #fff;
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255,255,255,0.3);
}

.btn-secondary:hover {
    background: rgba(255,255,255,0.25);
    transform: translateY(-2px);
}

.btn-download {
    background: var(--gradient);
    color: #fff;
    width: 100%;
    justify-content: center;
    padding: 14px 20px;
    font-size: 15px;
}

.btn-download:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99,102,241,0.35);
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    z-index: 1000;
    background: rgba(255,255,255,0.9);
    backdrop-filter: blur(20px);
    border-bottom: 1px solid transparent;
    transition: var(--transition);
}

.navbar.scrolled {
    background: rgba(255,255,255,0.98);
    box-shadow: 0 2px 20px rgba(0,0,0,0.08);
    border-bottom-color: var(--border-color);
}

.nav-container {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 70px;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 22px;
    font-weight: 800;
    background: var(--gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.nav-logo i {
    -webkit-text-fill-color: var(--primary);
    font-size: 28px;
}

.nav-menu {
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-menu li a {
    padding: 8px 16px;
    border-radius: var(--radius-sm);
    font-size: 15px;
    font-weight: 500;
    color: var(--text-secondary);
    display: flex;
    align-items: center;
    gap: 6px;
    transition: var(--transition);
}

.nav-menu li a:hover,
.nav-menu li a.active {
    color: var(--primary);
    background: rgba(99,102,241,0.08);
}

.nav-admin {
    background: var(--gradient) !important;
    color: #fff !important;
    border-radius: 50px !important;
    padding: 8px 20px !important;
}

.nav-admin:hover {
    opacity: 0.9 !important;
    transform: translateY(-1px);
}

.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    cursor: pointer;
    padding: 5px;
}

.nav-toggle span {
    display: block;
    width: 28px;
    height: 3px;
    background: var(--text-primary);
    border-radius: 3px;
    transition: var(--transition);
}

/* ===== Hero ===== */
.hero {
    padding: 140px 0 80px;
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #06b6d4 100%);
    position: relative;
    overflow: hidden;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url("data:image/svg+xml,%3Csvg width='60' height='60' viewBox='0 0 60 60' xmlns='http://www.w3.org/2000/svg'%3E%3Cg fill='none' fill-rule='evenodd'%3E%3Cg fill='%23ffffff' fill-opacity='0.05'%3E%3Cpath d='M36 34v-4h-2v4h-4v2h4v4h2v-4h4v-2h-4zm0-30V0h-2v4h-4v2h4v4h2V6h4V4h-4zM6 34v-4H4v4H0v2h4v4h2v-4h4v-2H6zM6 4V0H4v4H0v2h4v4h2V6h4V4H6z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
}

.hero-content {
    display: flex;
    align-items: center;
    gap: 60px;
    position: relative;
    z-index: 1;
}

.hero-text {
    flex: 1;
    color: #fff;
}

.hero-text h1 {
    font-size: 48px;
    font-weight: 800;
    line-height: 1.2;
    margin-bottom: 20px;
    letter-spacing: -1px;
}

.hero-text p {
    font-size: 18px;
    opacity: 0.9;
    margin-bottom: 32px;
    max-width: 540px;
    line-height: 1.7;
}

.hero-buttons {
    display: flex;
    gap: 16px;
    margin-bottom: 40px;
}

.hero-stats {
    display: flex;
    gap: 40px;
}

.stat-item {
    display: flex;
    flex-direction: column;
}

.stat-number {
    font-size: 28px;
    font-weight: 800;
}

.stat-label {
    font-size: 14px;
    opacity: 0.8;
}

.hero-image {
    flex: 1;
    display: flex;
    justify-content: center;
}

.hero-image-wrapper {
    position: relative;
    max-width: 450px;
}

.hero-img {
    border-radius: var(--radius);
    box-shadow: 0 20px 60px rgba(0,0,0,0.2);
    transition: var(--transition);
}

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

.hero-badge {
    position: absolute;
    bottom: -15px;
    right: -15px;
    background: #fff;
    color: var(--primary);
    padding: 8px 16px;
    border-radius: 50px;
    font-weight: 600;
    font-size: 14px;
    display: flex;
    align-items: center;
    gap: 6px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.15);
}

.hero-wave {
    position: absolute;
    bottom: -1px;
    left: 0;
    width: 100%;
    line-height: 0;
}

.hero-wave svg {
    width: 100%;
    height: 60px;
}

/* ===== 通用 Section ===== */
.section-header {
    text-align: center;
    margin-bottom: 50px;
}

.section-header h2 {
    font-size: 36px;
    font-weight: 800;
    color: var(--text-primary);
    margin-bottom: 12px;
    letter-spacing: -0.5px;
}

.section-header p {
    font-size: 18px;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* ===== 功能介绍 ===== */
.features {
    padding: 100px 0;
    background: var(--bg-color);
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 30px;
}

.feature-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 36px 28px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

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

.feature-icon {
    width: 56px;
    height: 56px;
    border-radius: 16px;
    background: linear-gradient(135deg, rgba(99,102,241,0.1), rgba(139,92,246,0.1));
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 20px;
}

.feature-icon i {
    font-size: 24px;
    color: var(--primary);
}

.feature-card h3 {
    font-size: 20px;
    font-weight: 700;
    margin-bottom: 10px;
}

.feature-card p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
}

/* ===== 下载区域 ===== */
.download {
    padding: 100px 0;
    background: var(--card-bg);
}

.download-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 24px;
}

.download-card {
    background: var(--bg-color);
    border-radius: var(--radius);
    padding: 32px 24px;
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
}

.download-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary);
}

.download-icon {
    width: 72px;
    height: 72px;
    border-radius: 50%;
    background: var(--gradient);
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 20px;
}

.download-icon i {
    font-size: 32px;
    color: #fff;
}

.download-card h3 {
    font-size: 22px;
    font-weight: 700;
    margin-bottom: 8px;
}

.download-card p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 16px;
}

.download-info {
    display: flex;
    justify-content: center;
    gap: 16px;
    font-size: 13px;
    color: var(--text-light);
    margin-bottom: 20px;
}

.download-info span {
    display: flex;
    align-items: center;
    gap: 4px;
}

/* ===== 指南区域 ===== */
.guides {
    padding: 100px 0;
    background: var(--bg-color);
}

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

.guide-card {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 28px 24px;
    box-shadow: var(--shadow);
    transition: var(--transition);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    position: relative;
    overflow: hidden;
}

.guide-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 4px;
    background: var(--gradient);
    opacity: 0;
    transition: var(--transition);
}

.guide-card:hover {
    transform: translateY(-6px);
    box-shadow: var(--shadow-hover);
    border-color: var(--primary);
}

.guide-card:hover::before {
    opacity: 1;
}

.guide-icon {
    width: 48px;
    height: 48px;
    border-radius: 12px;
    background: linear-gradient(135deg, rgba(99,102,241,0.1), rgba(6,182,212,0.1));
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 16px;
}

.guide-icon i {
    font-size: 20px;
    color: var(--primary);
}

.guide-card h3 {
    font-size: 18px;
    font-weight: 700;
    margin-bottom: 8px;
}

.guide-card p {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 16px;
    flex: 1;
}

.guide-date {
    font-size: 13px;
    color: var(--text-light);
    display: flex;
    align-items: center;
    gap: 4px;
}

.guide-arrow {
    position: absolute;
    bottom: 20px;
    right: 24px;
    color: var(--primary);
    font-size: 18px;
    transition: var(--transition);
}

.guide-card:hover .guide-arrow {
    transform: translateX(4px);
}

.empty-guides {
    grid-column: 1 / -1;
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-guides i {
    font-size: 64px;
    color: var(--text-light);
    margin-bottom: 20px;
}

.empty-guides h3 {
    font-size: 24px;
    margin-bottom: 12px;
}

.empty-guides p {
    margin-bottom: 24px;
}

/* ===== FAQ 区域 ===== */
.faq {
    padding: 100px 0;
    background: var(--card-bg);
}

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

.faq-item {
    border: 1px solid var(--border-color);
    border-radius: var(--radius);
    margin-bottom: 16px;
    overflow: hidden;
    transition: var(--transition);
}

.faq-item:hover {
    border-color: var(--primary);
}

.faq-question {
    padding: 20px 24px;
    display: flex;
    justify-content: space-between;
    align-items: center;
    cursor: pointer;
    background: var(--bg-color);
    transition: var(--transition);
}

.faq-question:hover {
    background: rgba(99,102,241,0.05);
}

.faq-question h3 {
    font-size: 17px;
    font-weight: 600;
}

.faq-question i {
    font-size: 16px;
    color: var(--text-light);
    transition: var(--transition);
}

.faq-item.active .faq-question i {
    transform: rotate(180deg);
    color: var(--primary);
}

.faq-answer {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
    padding: 0 24px;
}

.faq-item.active .faq-answer {
    max-height: 300px;
    padding: 0 24px 20px;
}

.faq-answer p {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.8;
}

/* ===== 页脚 ===== */
.footer {
    background: #1e293b;
    color: #cbd5e1;
    padding-top: 60px;
}

.footer-grid {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 40px;
    padding-bottom: 40px;
}

.footer-about h3 {
    font-size: 22px;
    color: #fff;
    margin-bottom: 16px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.footer-about p {
    font-size: 14px;
    line-height: 1.8;
    margin-bottom: 20px;
}

.footer-social {
    display: flex;
    gap: 12px;
}

.footer-social a {
    width: 40px;
    height: 40px;
    border-radius: 50%;
    background: rgba(255,255,255,0.1);
    display: flex;
    align-items: center;
    justify-content: center;
    color: #94a3b8;
    transition: var(--transition);
}

.footer-social a:hover {
    background: var(--primary);
    color: #fff;
    transform: translateY(-3px);
}

.footer-links h4 {
    font-size: 18px;
    color: #fff;
    margin-bottom: 20px;
}

.footer-links ul li {
    margin-bottom: 10px;
}

.footer-links ul li a {
    color: #94a3b8;
    font-size: 14px;
    transition: var(--transition);
}

.footer-links ul li a:hover {
    color: var(--primary);
    padding-left: 4px;
}

.footer-contact h4 {
    font-size: 18px;
    color: #fff;
    margin-bottom: 20px;
}

.footer-contact p {
    font-size: 14px;
    margin-bottom: 12px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.footer-contact i {
    color: var(--primary);
    width: 20px;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding: 20px 0;
    text-align: center;
    font-size: 14px;
    color: #64748b;
}

/* ===== 回到顶部 ===== */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 48px;
    height: 48px;
    border-radius: 50%;
    background: var(--gradient);
    color: #fff;
    border: none;
    cursor: pointer;
    font-size: 20px;
    box-shadow: 0 4px 15px rgba(99,102,241,0.3);
    transition: var(--transition);
    opacity: 0;
    visibility: hidden;
    transform: translateY(20px);
    z-index: 999;
}

.back-to-top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0);
}

.back-to-top:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 25px rgba(99,102,241,0.4);
}

/* ===== 弹窗 ===== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    align-items: center;
    justify-content: center;
}

.modal.show {
    display: flex;
}

.modal-content {
    background: var(--card-bg);
    border-radius: var(--radius);
    padding: 40px;
    max-width: 420px;
    width: 90%;
    text-align: center;
    animation: modalIn 0.3s ease;
}

@keyframes modalIn {
    from {
        opacity: 0;
        transform: scale(0.9) translateY(20px);
    }
    to {
        opacity: 1;
        transform: scale(1) translateY(0);
    }
}

.modal-content h2 {
    font-size: 24px;
    margin-bottom: 12px;
    color: var(--primary);
}

.modal-content p {
    color: var(--text-secondary);
    margin-bottom: 24px;
}

.modal-close {
    float: right;
    font-size: 28px;
    cursor: pointer;
    color: var(--text-light);
    transition: var(--transition);
}

.modal-close:hover {
    color: var(--text-primary);
}

/* ===== 响应式 ===== */
@media (max-width: 992px) {
    .hero-content {
        flex-direction: column;
        text-align: center;
    }
    .hero-text p {
        margin: 0 auto 32px;
    }
    .hero-buttons {
        justify-content: center;
    }
    .hero-stats {
        justify-content: center;
    }
    .features-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .download-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .guides-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    .footer-grid {
        grid-template-columns: repeat(2, 1fr);
    }
}

@media (max-width: 768px) {
    .nav-menu {
        display: none;
        flex-direction: column;
        position: absolute;
        top: 70px;
        left: 0;
        width: 100%;
        background: rgba(255,255,255,0.98);
        backdrop-filter: blur(20px);
        padding: 20px;
        box-shadow: 0 10px 30px rgba(0,0,0,0.1);
        gap: 4px;
    }
    .nav-menu.active {
        display: flex;
    }
    .nav-toggle {
        display: flex;
    }
    .nav-toggle.active span:nth-child(1) {
        transform: rotate(45deg) translate(5px, 6px);
    }
    .nav-toggle.active span:nth-child(2) {
        opacity: 0;
    }
    .nav-toggle.active span:nth-child(3) {
        transform: rotate(-45deg) translate(5px, -6px);
    }
    .hero {
        padding: 120px 0 60px;
    }
    .hero-text h1 {
        font-size: 32px;
    }
    .hero-text p {
        font-size: 16px;
    }
    .hero-stats {
        gap: 24px;
    }
    .stat-number {
        font-size: 22px;
    }
    .features-grid {
        grid-template-columns: 1fr;
    }
    .download-grid {
        grid-template-columns: 1fr;
    }
    .guides-grid {
        grid-template-columns: 1fr;
    }
    .footer-grid {
        grid-template-columns: 1fr;
        text-align: center;
    }
    .footer-social {
        justify-content: center;
    }
    .section-header h2 {
        font-size: 28px;
    }
    .download-card {
        max-width: 320px;
        margin: 0 auto;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 0 16px;
    }
    .hero-text h1 {
        font-size: 26px;
    }
    .hero-buttons {
        flex-direction: column;
        align-items: center;
    }
    .hero-buttons .btn {
        width: 100%;
        max-width: 280px;
    }
    .hero-stats {
        flex-wrap: wrap;
        gap: 16px;
    }
    .features {
        padding: 60px 0;
    }
    .download {
        padding: 60px 0;
    }
    .guides {
        padding: 60px 0;
    }
    .faq {
        padding: 60px 0;
    }
}