/* 主题颜色变量 */
:root {
    --primary-color: #E74C3C;
    --secondary-color: #2C3E50;
    --text-color: #333;
    --text-light: #666;
    --bg-white: #fff;
    --bg-light: #f8f9fa;
    --border-color: #eee;
    --shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-hover: 0 4px 16px rgba(231, 76, 60, 0.2);
}

/* 通用容器 */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
}

/* 导航栏 */
.navbar {
    position: sticky;
    top: 0;
    background: var(--bg-white);
    box-shadow: var(--shadow);
    z-index: 1000;
    padding: 15px 0;
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

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

.logo {
    width: 40px;
    height: 40px;
}

.brand-name {
    font-size: 1.25rem;
    font-weight: 700;
    color: var(--secondary-color);
}

.nav-menu {
    display: flex;
    gap: 30px;
}

.nav-menu a {
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

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

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

.nav-toggle span {
    width: 25px;
    height: 3px;
    background: var(--secondary-color);
    border-radius: 2px;
    transition: all 0.3s;
}

/* Hero区域 */
.hero {
    background: linear-gradient(135deg, var(--secondary-color) 0%, var(--primary-color) 100%);
    color: var(--bg-white);
    padding: 80px 0;
    text-align: center;
}

.hero-title {
    font-size: 3rem;
    margin-bottom: 20px;
    font-weight: 700;
}

.hero-subtitle {
    font-size: 1.5rem;
    margin-bottom: 30px;
    opacity: 0.9;
}

.hero-features {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.feature-tag {
    background: rgba(255, 255, 255, 0.2);
    padding: 8px 20px;
    border-radius: 20px;
    font-size: 1rem;
    backdrop-filter: blur(10px);
}

.hero-actions {
    display: flex;
    gap: 20px;
    justify-content: center;
    flex-wrap: wrap;
}

/* 按钮 */
.btn {
    display: inline-block;
    padding: 12px 30px;
    border-radius: 6px;
    font-weight: 600;
    transition: all 0.3s;
    cursor: pointer;
}

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

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(255, 255, 255, 0.3);
}

.btn-secondary {
    background: transparent;
    color: var(--bg-white);
    border: 2px solid var(--bg-white);
}

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

.btn-download {
    background: var(--primary-color);
    color: var(--bg-white);
    width: 100%;
    text-align: center;
}

.btn-download:hover {
    background: #c0392b;
    transform: translateY(-2px);
    box-shadow: var(--shadow-hover);
}

/* 通用Section */
.section {
    padding: 80px 0;
}

.section:nth-child(even) {
    background: var(--bg-light);
}

.section-title {
    text-align: center;
    font-size: 2.5rem;
    color: var(--secondary-color);
    margin-bottom: 50px;
    position: relative;
}

.section-title::after {
    content: '';
    display: block;
    width: 60px;
    height: 4px;
    background: var(--primary-color);
    margin: 15px auto 0;
    border-radius: 2px;
}

/* 功能介绍网格 */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 30px;
}

.feature-card {
    background: var(--bg-white);
    padding: 40px 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.feature-icon {
    font-size: 3rem;
    margin-bottom: 20px;
}

.feature-card h3 {
    font-size: 1.5rem;
    color: var(--secondary-color);
    margin-bottom: 15px;
}

.feature-card p {
    color: var(--text-light);
    line-height: 1.8;
}

/* 下载区域 */
.download-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-bottom: 40px;
}

.download-card {
    background: var(--bg-white);
    padding: 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    transition: all 0.3s;
}

.download-card:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-hover);
}

.download-icon {
    font-size: 3rem;
    margin-bottom: 15px;
}

.download-card h3 {
    font-size: 1.2rem;
    color: var(--secondary-color);
    margin-bottom: 10px;
}

.version {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-bottom: 20px;
}

.contact-box {
    background: var(--bg-white);
    padding: 25px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    text-align: center;
    border-left: 4px solid var(--primary-color);
}

.contact-box strong {
    color: var(--primary-color);
    font-size: 1.2rem;
}

/* 二维码样式 */
.qrcode-image {
    width: 180px;
    height: 180px;
    margin: 0 auto 15px;
    border-radius: 8px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.qrcode-image:hover {
    transform: scale(1.05);
    box-shadow: var(--shadow-hover);
}

.qrcode-hint {
    color: var(--text-light);
    font-size: 0.9rem;
    margin-top: 0;
}

/* 操作步骤 */
.steps-container {
    max-width: 900px;
    margin: 0 auto;
}

.step-item {
    display: flex;
    align-items: flex-center;
    gap: 20px;
    margin-bottom: 30px;
    padding: 25px;
    background: var(--bg-white);
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: all 0.3s;
}

.step-item:hover {
    box-shadow: var(--shadow-hover);
}

.step-number {
    flex-shrink: 0;
    width: 40px;
    height: 40px;
    background: var(--primary-color);
    color: var(--bg-white);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: 700;
}

.step-content {
    flex: 1;
}

.step-content h4 {
    color: var(--secondary-color);
    margin: 0 0 15px 0;
    line-height: 40px;
}

.step-images {
    margin-top: 15px;
}

.step-images.single {
    display: flex;
    justify-content: center;
}

.step-images.multi {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 15px;
}

.preview-image {
    border-radius: 8px;
    box-shadow: var(--shadow);
    cursor: pointer;
    transition: all 0.3s;
    max-width: 100%;
}

.preview-image:hover {
    transform: scale(1.02);
    box-shadow: var(--shadow-hover);
}

/* 手风琴 */
.accordion-item {
    background: var(--bg-white);
    border-radius: 12px;
    margin-bottom: 20px;
    box-shadow: var(--shadow);
    overflow: hidden;
}

.accordion-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 25px 30px;
    cursor: pointer;
    transition: all 0.3s;
}

.accordion-header:hover {
    background: var(--bg-light);
}

.accordion-header h3 {
    color: var(--secondary-color);
    font-size: 1.3rem;
}

.accordion-icon {
    font-size: 2rem;
    color: var(--primary-color);
    font-weight: 300;
    transition: transform 0.3s;
}

.accordion-item.active .accordion-icon {
    transform: rotate(45deg);
}

.accordion-content {
    max-height: 0;
    overflow: hidden;
    transition: max-height 0.3s ease;
}

.accordion-item.active .accordion-content {
    max-height: 5000px;
}

.accordion-content > * {
    padding: 0 30px 30px;
}

.tutorial-list {
    list-style: decimal;
    padding-left: 50px;
}

.tutorial-list li {
    margin-bottom: 25px;
    color: var(--text-color);
    line-height: 1.8;
}

.tutorial-list .note {
    background: #fff3cd;
    border-left: 4px solid #ffc107;
    padding: 12px 15px;
    margin-top: 10px;
    border-radius: 4px;
    font-size: 0.95rem;
    color: #856404;
}

/* 页脚 */
.footer {
    background: var(--secondary-color);
    color: var(--bg-white);
    padding: 50px 0 20px;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 40px;
    margin-bottom: 30px;
}

.footer-section h4 {
    margin-bottom: 15px;
    color: var(--primary-color);
}

.footer-section p,
.footer-section li {
    margin-bottom: 8px;
    opacity: 0.9;
}

.footer-section a:hover {
    color: var(--primary-color);
}

.footer-bottom {
    border-top: 1px solid rgba(255, 255, 255, 0.1);
    padding-top: 20px;
    text-align: center;
    opacity: 0.8;
}

/* 图片灯箱 */
.lightbox {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.95);
    z-index: 9999;
    align-items: center;
    justify-content: center;
}

.lightbox.active {
    display: flex;
}

.lightbox-close {
    position: absolute;
    top: 20px;
    right: 40px;
    font-size: 3rem;
    color: var(--bg-white);
    cursor: pointer;
    z-index: 10001;
}

.lightbox-content {
    position: relative;
    max-width: 90%;
    max-height: 90%;
    display: flex;
    align-items: center;
}

.lightbox-image {
    max-width: 100%;
    max-height: 90vh;
    border-radius: 8px;
    touch-action: pinch-zoom;
    user-select: none;
}

.lightbox-prev,
.lightbox-next {
    position: absolute;
    font-size: 3rem;
    color: var(--bg-white);
    background: rgba(255, 255, 255, 0.1);
    padding: 10px 20px;
    cursor: pointer;
    border-radius: 4px;
    transition: all 0.3s;
}

.lightbox-prev:hover,
.lightbox-next:hover {
    background: rgba(255, 255, 255, 0.2);
}

.lightbox-prev {
    left: -80px;
}

.lightbox-next {
    right: -80px;
}

.lightbox-counter {
    position: absolute;
    bottom: 20px;
    left: 50%;
    transform: translateX(-50%);
    color: var(--bg-white);
    background: rgba(0, 0, 0, 0.6);
    padding: 8px 16px;
    border-radius: 20px;
    font-size: 0.9rem;
}

/* 返回顶部 */
.back-to-top {
    position: fixed;
    bottom: 30px;
    right: 30px;
    width: 50px;
    height: 50px;
    background: var(--primary-color);
    color: var(--bg-white);
    border-radius: 50%;
    font-size: 1.5rem;
    display: none;
    align-items: center;
    justify-content: center;
    cursor: pointer;
    box-shadow: var(--shadow);
    transition: all 0.3s;
    z-index: 1000;
}

.back-to-top.show {
    display: flex;
}

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