/* ===== 全局样式 ===== */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

:root {
    --primary-color: #1a73e8;
    --primary-hover: #1557b0;
    --secondary-color: #34a853;
    --text-primary: #202124;
    --text-secondary: #5f6368;
    --background: #ffffff;
    --background-alt: #f8f9fa;
    --border-color: #dadce0;
    --shadow: 0 1px 2px 0 rgba(60,64,67,.3), 0 1px 3px 1px rgba(60,64,67,.15);
    --shadow-lg: 0 2px 6px 2px rgba(60,64,67,.15), 0 1px 2px 0 rgba(60,64,67,.3);
    --transition: all 0.3s ease;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, "Noto Sans", "Microsoft YaHei", sans-serif;
    font-size: 16px;
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--background);
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* ===== 导航栏 ===== */
.navbar {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    background: var(--background);
    box-shadow: var(--shadow);
    z-index: 1000;
    transition: var(--transition);
}

.navbar.scrolled {
    box-shadow: var(--shadow-lg);
}

.nav-content {
    display: flex;
    align-items: center;
    justify-content: space-between;
    height: 64px;
}

.nav-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 20px;
    font-weight: 600;
    color: var(--text-primary);
    text-decoration: none;
}

.logo {
    width: 40px;
    height: 40px;
    border-radius: 8px;
}

.nav-menu {
    display: flex;
    list-style: none;
    gap: 32px;
    margin: 0;
}

.nav-link {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    padding: 8px 0;
}

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

.nav-buttons {
    display: flex;
    gap: 12px;
}

.mobile-menu-toggle {
    display: none;
    flex-direction: column;
    gap: 4px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
}

.mobile-menu-toggle span {
    width: 24px;
    height: 2px;
    background: var(--text-primary);
    transition: var(--transition);
}

/* ===== 按钮 ===== */
.btn {
    display: inline-block;
    padding: 10px 24px;
    border-radius: 8px;
    font-weight: 500;
    text-decoration: none;
    text-align: center;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    font-size: 14px;
}

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

.btn-primary:hover {
    background: var(--primary-hover);
    box-shadow: var(--shadow-lg);
}

.btn-large {
    padding: 16px 48px;
    font-size: 18px;
    border-radius: 12px;
}

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

.btn-white:hover {
    box-shadow: var(--shadow-lg);
    transform: translateY(-2px);
}

/* ===== 首屏横幅 ===== */
.hero {
    position: relative;
    padding: 120px 0 40px;
    background: linear-gradient(135deg, #0d47a1 0%, #1565c0 100%);
    color: white;
    overflow: hidden;
}

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

.hero-text {
    text-align: center;
    width: 100%;
}

.hero-title {
    font-size: 48px;
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 40px;
    white-space: nowrap;
}

.hero-subtitle {
    font-size: 20px;
    margin-bottom: 48px;
    opacity: 0.95;
    line-height: 1.6;
}

.hero-cta {
    display: flex;
    gap: 16px;
    justify-content: center;
    margin-top: 30px;
    margin-bottom: 0;
}

/* ===== 功能介绍 ===== */
.features {
    padding: 80px 0;
    background: var(--background);
}

.section-title {
    font-size: 36px;
    font-weight: 700;
    text-align: center;
    margin-bottom: 16px;
    color: var(--text-primary);
}

.section-subtitle {
    font-size: 18px;
    text-align: center;
    color: var(--text-secondary);
    margin-bottom: 60px;
}

/* 功能Tab导航 */
.feature-tabs {
    display: flex;
    justify-content: center;
    gap: 16px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.feature-tab {
    display: flex;
    align-items: center;
    gap: 12px;
    padding: 16px 32px;
    background: var(--background);
    border: 2px solid var(--border-color);
    border-radius: 12px;
    font-size: 18px;
    font-weight: 600;
    color: var(--text-secondary);
    cursor: pointer;
    transition: var(--transition);
}

.feature-tab:hover {
    border-color: var(--primary-color);
    color: var(--primary-color);
    box-shadow: var(--shadow);
}

.feature-tab.active {
    background: var(--primary-color);
    border-color: var(--primary-color);
    color: white;
    box-shadow: var(--shadow-lg);
}

.feature-tab .tab-icon {
    font-size: 24px;
}

.feature-tab .tab-text {
    font-size: 16px;
}

/* 功能面板 */
.feature-panels {
    position: relative;
    min-height: 400px;
}

.feature-panel {
    display: none;
    animation: fadeIn 0.5s ease;
}

.feature-panel.active {
    display: grid;
    grid-template-columns: 1.5fr 1fr;
    gap: 40px;
    align-items: center;
    background: white;
    border-radius: 16px;
    padding: 40px;
    box-shadow: var(--shadow);
}

@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.feature-panel-image {
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-lg);
}

.feature-panel-image img {
    width: 100%;
    height: auto;
    display: block;
}

.feature-panel-content h3 {
    font-size: 28px;
    font-weight: 700;
    margin-bottom: 20px;
    color: var(--text-primary);
}

.feature-panel-content p {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-secondary);
}

/* ===== 操作步骤 ===== */
.steps {
    padding: 80px 0;
    background: var(--background-alt);
}

/* 流程概览 - 首页顶部专用样式 */
.hero .process-overview {
    display: flex !important;
    justify-content: center !important;
    align-items: center !important;
    gap: 16px;
    margin: 0 auto;
    padding: 0 !important;
    background: transparent !important;
    box-shadow: none !important;
    border-radius: 0 !important;
    width: 100%;
    text-align: center;
}

.hero .process-step {
    font-size: 18px;
    font-weight: 500;
    color: rgba(255, 255, 255, 0.95);
    white-space: nowrap;
}

.hero .process-divider {
    font-size: 18px;
    color: rgba(255, 255, 255, 0.6);
    font-weight: 300;
}

/* 流程概览 - 通用样式 */
.process-overview {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 20px;
    margin: 40px auto 60px;
    padding: 24px 40px;
    background: white;
    border-radius: 50px;
    box-shadow: var(--shadow);
    max-width: fit-content;
}

.process-step {
    font-size: 18px;
    font-weight: 600;
    color: var(--primary-color);
    white-space: nowrap;
}

.process-divider {
    font-size: 20px;
    color: var(--border-color);
    font-weight: 300;
}

.steps-container {
    max-width: 900px;
    margin: 0 auto;
}

.step-item {
    display: grid;
    grid-template-columns: 80px 1fr;
    gap: 32px;
    margin-bottom: 60px;
    position: relative;
}

.step-item:not(:last-child)::after {
    content: '';
    position: absolute;
    left: 40px;
    top: 80px;
    width: 2px;
    height: calc(100% - 40px);
    background: linear-gradient(to bottom, var(--primary-color), transparent);
}

.step-number {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--primary-color), var(--secondary-color));
    color: white;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 28px;
    font-weight: 700;
    box-shadow: var(--shadow-lg);
}

.step-content {
    background: white;
    border-radius: 16px;
    padding: 32px;
    box-shadow: var(--shadow);
}

.step-title {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 12px;
    color: var(--text-primary);
}

.step-description {
    color: var(--text-secondary);
    line-height: 1.6;
    margin-bottom: 20px;
}

.step-image {
    margin-top: 20px;
    border-radius: 12px;
    overflow: hidden;
}

.step-image img {
    width: 100%;
    height: auto;
    display: block;
}

/* ===== CTA区域 ===== */
.cta-section {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    text-align: center;
}

.cta-title {
    font-size: 40px;
    font-weight: 700;
    margin-bottom: 16px;
}

.cta-description {
    font-size: 18px;
    margin-bottom: 32px;
    opacity: 0.95;
}

/* ===== 页脚 ===== */
.footer {
    background: var(--text-primary);
    color: white;
    padding: 60px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 40px;
}

.footer-brand {
    display: flex;
    align-items: center;
    gap: 12px;
    margin-bottom: 16px;
}

.footer-logo {
    width: 40px;
    height: 40px;
    border-radius: 8px;
}

.footer-brand-name {
    font-size: 18px;
    font-weight: 600;
}

.footer-tagline {
    opacity: 0.8;
    margin-bottom: 12px;
}

.footer-copyright {
    opacity: 0.6;
    font-size: 14px;
}

.footer-title {
    font-size: 16px;
    font-weight: 600;
    margin-bottom: 16px;
}

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

.footer-links li {
    margin-bottom: 8px;
}

.footer-links a {
    color: rgba(255,255,255,0.8);
    text-decoration: none;
    transition: var(--transition);
}

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

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

.footer-contact li {
    margin-bottom: 8px;
    opacity: 0.8;
}

.footer-bottom {
    border-top: 1px solid rgba(255,255,255,0.1);
    padding-top: 20px;
    text-align: center;
}

.footer-beian a {
    color: rgba(255,255,255,0.6);
    text-decoration: none;
    font-size: 14px;
}

.footer-beian a:hover {
    color: rgba(255,255,255,0.8);
}

/* ===== 模态窗口 ===== */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    z-index: 2000;
}

.modal.active {
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-overlay {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0,0,0,0.5);
    backdrop-filter: blur(4px);
}

.modal-content {
    position: relative;
    background: white;
    border-radius: 16px;
    max-width: 600px;
    width: 90%;
    max-height: 90vh;
    overflow-y: auto;
    box-shadow: 0 20px 60px rgba(0,0,0,0.3);
    animation: modalSlideIn 0.3s ease;
}

@keyframes modalSlideIn {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.modal-close {
    position: absolute;
    top: 16px;
    right: 16px;
    width: 32px;
    height: 32px;
    border: none;
    background: var(--background-alt);
    border-radius: 50%;
    font-size: 24px;
    cursor: pointer;
    transition: var(--transition);
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    background: var(--border-color);
}

.modal-header {
    padding: 32px 32px 0;
}

.modal-header h3 {
    font-size: 24px;
    font-weight: 600;
}

.modal-body {
    padding: 32px;
}

.install-option {
    display: flex;
    flex-direction: row;
    gap: 16px;
    align-items: center;
    padding: 24px;
    border: 2px solid var(--border-color);
    border-radius: 12px;
    margin-bottom: 24px;
}

.install-option .install-info {
    flex: 1;
}

.install-icon {
    font-size: 48px;
    flex-shrink: 0;
    display: flex;
    align-items: center;
    justify-content: center;
}

.install-icon img {
    width: 48px;
    height: 48px;
    object-fit: contain;
}

.install-info h4 {
    font-size: 18px;
    margin-bottom: 4px;
}

.install-info p {
    color: var(--text-secondary);
    font-size: 14px;
}

.install-divider {
    text-align: center;
    position: relative;
    margin: 24px 0;
}

.install-divider::before {
    content: '';
    position: absolute;
    left: 0;
    top: 50%;
    width: 100%;
    height: 1px;
    background: var(--border-color);
}

.install-divider span {
    position: relative;
    background: white;
    padding: 0 16px;
    color: var(--text-secondary);
}

.install-help {
    text-align: center;
}

.install-link {
    color: var(--primary-color);
    text-decoration: none;
    font-weight: 500;
}

.install-link:hover {
    text-decoration: underline;
}

/* ===== 响应式设计 ===== */
@media (max-width: 768px) {
    .nav-menu,
    .nav-buttons {
        display: none;
    }
    
    .mobile-menu-toggle {
        display: flex;
    }
    
    .nav-menu.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 64px;
        left: 0;
        right: 0;
        background: white;
        padding: 20px;
        box-shadow: var(--shadow-lg);
    }
    
    .hero {
        padding: 90px 0 40px;
    }
    
    .hero-title {
        font-size: 32px;
    }
    
    .hero-subtitle {
        font-size: 16px;
    }
    
    .hero .process-overview {
        gap: 12px;
        margin: 24px 0;
    }
    
    .hero .process-step {
        font-size: 16px;
    }
    
    .hero .process-divider {
        font-size: 16px;
    }
    
    .feature-tabs {
        flex-direction: column;
        padding: 0 20px;
    }
    
    .feature-tab {
        width: 100%;
        justify-content: center;
    }
    
    .feature-panel.active {
        grid-template-columns: 1fr;
        gap: 24px;
        padding: 24px;
    }
    
    .feature-panel-content h3 {
        font-size: 22px;
    }
    
    .feature-panel-content p {
        font-size: 14px;
    }
    
    .process-overview {
        flex-direction: column;
        gap: 12px;
        padding: 20px 30px;
        margin: 30px auto 40px;
    }
    
    .process-divider {
        transform: rotate(90deg);
        font-size: 16px;
    }
    
    .process-step {
        font-size: 16px;
        text-align: center;
    }
    
    .step-item {
        grid-template-columns: 1fr;
        gap: 20px;
    }
    
    .step-item:not(:last-child)::after {
        display: none;
    }
    
    .step-number {
        width: 60px;
        height: 60px;
        font-size: 24px;
        margin: 0 auto;
    }
    
    .section-title {
        font-size: 28px;
    }
    
    .cta-title {
        font-size: 28px;
    }
    
    .install-option {
        flex-direction: column;
        text-align: center;
    }
    
    .install-option .btn {
        width: 100%;
    }
}

@media (max-width: 480px) {
    .hero {
        padding: 80px 0 40px;
    }
    
    .hero-title {
        font-size: 28px;
    }
    
    .hero-subtitle {
        font-size: 14px;
        margin-bottom: 32px;
    }
    
    .btn-large {
        padding: 14px 32px;
        font-size: 16px;
        width: 100%;
    }
    
    .hero .process-overview {
        gap: 8px;
        margin: 20px 0;
        flex-wrap: wrap;
    }
    
    .hero .process-step {
        font-size: 14px;
    }
    
    .hero .process-divider {
        font-size: 14px;
    }
}