/* 基础样式 */
:root {
    --primary-color: #28a745;
    --primary-dark: #1e7e34;
    --secondary-color: #6c757d;
    --accent-color: #ffc107;
    --text-color: #333;
    --text-light: #666;
    --bg-light: #f8f9fa;
    --bg-white: #ffffff;
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.15);
    --radius: 12px;
    --radius-lg: 20px;
    --transition: all 0.3s ease;
}

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

body {
    font-family: 'Noto Sans SC', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--bg-white);
}

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

/* 世界语文本样式 - 提高可读性 */
.esperanto-text {
    color: #4a4a4a;
    font-style: italic;
    font-weight: 500;
    letter-spacing: 0.3px;
}

/* 卡片内的世界语文本 */
.about-card .esperanto-text,
.activity-card .esperanto-text,
.contact-item .esperanto-text {
    display: block;
    margin-top: 0.5rem;
    color: #555;
    font-size: 0.95em;
}

/* 标题中的世界语文本 */
h2 .esperanto-text,
h3 .esperanto-text,
h4 .esperanto-text {
    display: block;
    font-size: 0.75em;
    color: #666;
    margin-top: 0.3rem;
}

/* 标签中的世界语文本 */
.tag .esperanto-text {
    font-size: 0.8em;
    color: rgba(255,255,255,0.95);
}

/* 副标题中的世界语文本 */
.section-subtitle .esperanto-text {
    color: #666;
    font-size: 0.9em;
}

/* 图注中的世界语文本 */
.gallery-caption .esperanto-text {
    color: #555;
    font-size: 0.9em;
    display: block;
    margin-top: 0.3rem;
}

/* 导航栏中的世界语文本 */
.nav a .esperanto-text {
    display: block;
    font-size: 0.75rem;
    color: rgba(255,255,255,0.9);
    margin-top: 0.2rem;
}

/* 活动说明中的世界语文本 */
.activity-note .esperanto-text {
    color: #555;
    font-size: 0.95em;
}

/* Zoom信息中的世界语文本 */
.zoom-info .esperanto-text {
    color: #555;
    font-size: 0.85em;
}

/* 时间地点信息中的世界语文本 */
.time .esperanto-text,
.location .esperanto-text {
    color: #555;
    font-size: 0.9em;
}

/* 描述文字中的世界语文本 */
.description .esperanto-text {
    color: #555;
    display: block;
    margin-top: 0.5rem;
}

/* 国际交流区域的世界语文本 */
.international-content .esperanto-text {
    color: #555;
}

/* 国家标签中的世界语文本 */
.country .esperanto-text {
    color: #666;
    font-size: 0.8em;
}

/* 深色背景上的世界语文本 */
.bg-dark .esperanto-text,
.hero .esperanto-text,
.footer .esperanto-text {
    color: rgba(255, 255, 255, 0.95);
    text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

/* 头部导航 */
.header {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    color: white;
    padding: 1rem 0;
    box-shadow: var(--shadow);
    position: sticky;
    top: 0;
    z-index: 100;
}

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

.logo {
    display: flex;
    align-items: center;
    gap: 10px;
}

.esperanto-logo {
    font-size: 2rem;
}

.logo-text {
    display: flex;
    flex-direction: column;
}

.logo h1 {
    font-size: 1.5rem;
    font-weight: 700;
    line-height: 1.2;
}

.logo .subtitle {
    font-size: 0.85rem;
    opacity: 0.9;
    font-style: italic;
}

.nav {
    display: flex;
    gap: 2rem;
}

.nav a {
    color: white;
    text-decoration: none;
    font-weight: 500;
    transition: var(--transition);
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
}

.nav a:hover {
    background: rgba(255, 255, 255, 0.2);
}

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

.hero h2 {
    font-size: 3rem;
    margin-bottom: 1rem;
    font-weight: 700;
}

.hero .subtitle {
    font-size: 1.3rem;
    margin-bottom: 2rem;
    opacity: 0.9;
    font-style: italic;
}

.hero .description {
    max-width: 700px;
    margin: 0 auto 2rem;
    font-size: 1.1rem;
    line-height: 1.8;
    opacity: 0.95;
}

.btn-primary {
    display: inline-block;
    background: var(--accent-color);
    color: #333;
    padding: 1rem 2.5rem;
    border-radius: 50px;
    text-decoration: none;
    font-weight: 600;
    transition: var(--transition);
    box-shadow: var(--shadow);
}

.btn-primary:hover {
    transform: translateY(-3px);
    box-shadow: var(--shadow-lg);
    background: #ffd54f;
}

/* 章节标题 */
.section-title {
    text-align: center;
    font-size: 2.5rem;
    margin-bottom: 3rem;
    color: var(--text-color);
    position: relative;
    padding-bottom: 1rem;
}

.section-title::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 50%;
    transform: translateX(-50%);
    width: 80px;
    height: 4px;
    background: linear-gradient(135deg, var(--primary-color) 0%, #20c997 100%);
    border-radius: 2px;
}

.section-subtitle {
    text-align: center;
    color: var(--text-light);
    margin-top: -2rem;
    margin-bottom: 3rem;
    font-size: 1.1rem;
}

/* 关于我们 */
.about {
    padding: 80px 0;
    background: var(--bg-light);
}

.about-intro {
    max-width: 800px;
    margin: 0 auto 3rem;
    text-align: center;
}

.about-text {
    font-size: 1.1rem;
    line-height: 1.8;
    color: var(--text-light);
}

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

.about-card {
    background: white;
    padding: 2.5rem;
    border-radius: var(--radius-lg);
    text-align: center;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

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

.about-card .icon {
    font-size: 3rem;
    margin-bottom: 1rem;
}

.about-card h3 {
    font-size: 1.3rem;
    margin-bottom: 1rem;
    color: var(--primary-color);
}

.about-card p {
    color: var(--text-light);
    line-height: 1.7;
}

/* 国际交流部分 */
.international {
    padding: 80px 0;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
}

.international .section-title,
.international .section-subtitle {
    color: white;
}

.international .section-title::after {
    background: rgba(255, 255, 255, 0.5);
}

.international-content {
    max-width: 900px;
    margin: 0 auto;
    text-align: center;
}

.international-text {
    font-size: 1.1rem;
    line-height: 1.8;
    margin-bottom: 2rem;
    opacity: 0.95;
}

.country-flags {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
    margin: 2rem 0;
}

.country {
    background: rgba(255, 255, 255, 0.2);
    padding: 0.8rem 1.2rem;
    border-radius: 30px;
    font-size: 1.1rem;
    backdrop-filter: blur(10px);
    transition: var(--transition);
}

.country:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-3px);
}

/* 活动区域 */
.activities {
    padding: 80px 0;
    background: white;
}

.activity-note {
    max-width: 800px;
    margin: 3rem auto 0;
    padding: 1.5rem;
    background: var(--bg-light);
    border-radius: var(--radius);
    border-left: 4px solid var(--primary-color);
}

.activity-note p {
    color: var(--text-light);
    line-height: 1.7;
}

.zoom-info {
    background: #f0f7ff;
    padding: 1rem;
    border-radius: var(--radius);
    margin: 1rem 0;
    border-left: 3px solid #007bff;
}

.zoom-info p {
    margin: 0.3rem 0;
    font-family: monospace;
    font-size: 1rem;
}

.event-links {
    margin-top: 1rem;
}

.event-link {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 0.5rem 1rem;
    border-radius: var(--radius);
    text-decoration: none;
    transition: var(--transition);
}

.event-link:hover {
    background: var(--primary-dark);
}

.contact-item a {
    color: var(--primary-color);
    text-decoration: none;
}

.contact-item a:hover {
    text-decoration: underline;
}

.activity-list {
    display: flex;
    flex-direction: column;
    gap: 2rem;
}

.activity-card {
    display: flex;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
    overflow: hidden;
    transition: var(--transition);
    border-left: 5px solid var(--primary-color);
}

.activity-card:hover {
    transform: translateX(5px);
    box-shadow: var(--shadow-lg);
}

.activity-card.past {
    border-left-color: var(--secondary-color);
    opacity: 0.8;
}

.activity-date {
    background: linear-gradient(135deg, var(--primary-color) 0%, #20c997 100%);
    color: white;
    padding: 2rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    min-width: 100px;
}

.activity-card.past .activity-date {
    background: linear-gradient(135deg, var(--secondary-color) 0%, #868e96 100%);
}

.activity-date .day {
    font-size: 2.5rem;
    font-weight: 700;
    line-height: 1;
}

.activity-date .month {
    font-size: 1rem;
    margin-top: 0.5rem;
}

.activity-content {
    padding: 2rem;
    flex: 1;
}

.activity-content h3 {
    font-size: 1.4rem;
    margin-bottom: 1rem;
    color: var(--text-color);
}

.activity-content .time,
.activity-content .location {
    color: var(--text-light);
    margin-bottom: 0.5rem;
    font-size: 0.95rem;
}

.activity-content .description {
    margin: 1rem 0;
    color: var(--text-light);
    line-height: 1.7;
}

.tag {
    display: inline-block;
    background: var(--primary-color);
    color: white;
    padding: 0.3rem 1rem;
    border-radius: 20px;
    font-size: 0.85rem;
    font-weight: 500;
}

.tag.online {
    background: #007bff;
}

.tag.past {
    background: var(--secondary-color);
}

/* 画廊 */
.gallery {
    padding: 80px 0;
    background: var(--bg-light);
}

.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
}

.gallery-item {
    background: white;
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: var(--shadow);
    transition: var(--transition);
}

.gallery-item:hover {
    transform: translateY(-5px);
    box-shadow: var(--shadow-lg);
}

.gallery-image {
    width: 100%;
    height: 250px;
    object-fit: cover;
    display: block;
}

.image-placeholder {
    height: 250px;
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    color: white;
}

.image-placeholder span {
    font-size: 4rem;
    margin-bottom: 1rem;
}

.image-placeholder p {
    font-size: 1.2rem;
    font-weight: 500;
}

.gallery-caption {
    padding: 1.5rem;
}

.gallery-caption h4 {
    font-size: 1.2rem;
    margin-bottom: 0.5rem;
}

.gallery-caption p {
    color: var(--text-light);
    font-size: 0.95rem;
}

/* 联系区域 */
.contact {
    padding: 80px 0;
    background: white;
}

.contact-content {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 3rem;
    align-items: start;
}

.contact-info {
    display: flex;
    flex-direction: column;
    gap: 1.5rem;
}

.contact-item {
    display: flex;
    align-items: flex-start;
    gap: 1rem;
    padding: 1.5rem;
    background: var(--bg-light);
    border-radius: var(--radius);
}

.contact-item .icon {
    font-size: 2rem;
}

.contact-item h4 {
    margin-bottom: 0.3rem;
    color: var(--primary-color);
}

.contact-item p {
    color: var(--text-light);
}

.join-card {
    background: linear-gradient(135deg, #28a745 0%, #20c997 100%);
    color: white;
    padding: 3rem;
    border-radius: var(--radius-lg);
    text-align: center;
}

.join-card h3 {
    font-size: 1.8rem;
    margin-bottom: 1rem;
}

.join-card p {
    margin-bottom: 1.5rem;
    opacity: 0.95;
}

.esperanto-quote {
    font-size: 1.3rem;
    font-style: italic;
    margin: 1.5rem 0 0.5rem !important;
}

.quote-translation {
    font-size: 0.95rem;
    opacity: 0.9;
    margin-bottom: 2rem !important;
}

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

.join-card .btn-primary:hover {
    background: var(--bg-light);
}

/* 页脚 */
.footer {
    background: #2c3e50;
    color: white;
    padding: 3rem 0;
    text-align: center;
}

.footer-logo {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 10px;
    margin-bottom: 1rem;
}

.footer-logo > div {
    display: flex;
    flex-direction: column;
    text-align: left;
}

.footer-logo span:first-of-type {
    font-size: 1.3rem;
    font-weight: 600;
}

.footer-subtitle {
    font-size: 0.9rem;
    opacity: 0.8;
    font-style: italic;
}

.copyright {
    color: rgba(255, 255, 255, 0.7);
    font-size: 0.95rem;
    line-height: 1.8;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .header .container {
        flex-direction: column;
        gap: 1rem;
    }

    .nav {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.5rem;
    }

    .nav a {
        padding: 0.3rem 0.8rem;
        font-size: 0.9rem;
    }

    .logo h1 {
        font-size: 1.2rem;
    }

    .logo .subtitle {
        font-size: 0.75rem;
    }

    .hero h2 {
        font-size: 1.8rem;
    }

    .hero .subtitle {
        font-size: 1rem;
    }

    .section-title {
        font-size: 1.8rem;
    }

    .activity-card {
        flex-direction: column;
    }

    .activity-date {
        flex-direction: row;
        padding: 1rem;
        gap: 0.5rem;
        justify-content: center;
    }

    .country-flags {
        gap: 0.5rem;
    }

    .country {
        padding: 0.5rem 0.8rem;
        font-size: 0.95rem;
    }

    .contact-content {
        grid-template-columns: 1fr;
    }

    .about-grid,
    .gallery-grid {
        grid-template-columns: 1fr;
    }

    .zoom-info p {
        font-size: 0.9rem;
    }
}

/* 平板设备 (768px - 1024px) */
@media (max-width: 1024px) {
    .container {
        padding: 0 15px;
    }
    
    .about-grid {
        grid-template-columns: repeat(2, 1fr);
        gap: 1.5rem;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(2, 1fr);
    }
    
    .contact-content {
        gap: 2rem;
    }
    
    .hero h2 {
        font-size: 2.2rem;
    }
    
    .section-title {
        font-size: 2rem;
    }
}

/* 小平板和大手机 (481px - 767px) */
@media (max-width: 767px) {
    .header {
        padding: 0.8rem 0;
    }
    
    .header .container {
        flex-direction: column;
        gap: 0.8rem;
    }
    
    .logo {
        justify-content: center;
    }
    
    .nav {
        flex-wrap: wrap;
        justify-content: center;
        gap: 0.4rem;
    }
    
    .nav a {
        padding: 0.4rem 0.7rem;
        font-size: 0.85rem;
    }
    
    .nav a .esperanto-text {
        display: none; /* 小屏幕上隐藏世界语文本以节省空间 */
    }
    
    .hero {
        padding: 60px 0;
    }
    
    .hero h2 {
        font-size: 1.6rem;
    }
    
    .hero .subtitle {
        font-size: 0.95rem;
    }
    
    .about-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .about-card {
        padding: 1.5rem;
    }
    
    .about-card .icon {
        font-size: 2.5rem;
    }
    
    .activity-card {
        flex-direction: column;
    }
    
    .activity-date {
        flex-direction: row;
        padding: 1rem;
        gap: 0.5rem;
        justify-content: center;
        min-width: auto;
    }
    
    .activity-date .day {
        font-size: 2rem;
    }
    
    .activity-content {
        padding: 1.5rem;
    }
    
    .activity-content h3 {
        font-size: 1.2rem;
    }
    
    .country-flags {
        gap: 0.5rem;
    }
    
    .country {
        padding: 0.5rem 0.8rem;
        font-size: 0.9rem;
    }
    
    .gallery-grid {
        grid-template-columns: 1fr;
        gap: 1.5rem;
    }
    
    .gallery-image,
    .image-placeholder {
        height: 200px;
    }
    
    .contact-content {
        grid-template-columns: 1fr;
        gap: 2rem;
    }
    
    .join-card {
        padding: 2rem;
    }
    
    .join-card h3 {
        font-size: 1.5rem;
    }
    
    .section-title {
        font-size: 1.6rem;
    }
    
    .section-subtitle {
        font-size: 1rem;
    }
    
    .about, .activities, .gallery, .contact {
        padding: 50px 0;
    }
}

/* 小手机 (320px - 480px) */
@media (max-width: 480px) {
    .container {
        padding: 0 12px;
    }
    
    .header {
        padding: 0.6rem 0;
    }
    
    .logo h1 {
        font-size: 1.1rem;
    }
    
    .logo .subtitle {
        font-size: 0.7rem;
    }
    
    .nav {
        gap: 0.3rem;
    }
    
    .nav a {
        padding: 0.3rem 0.6rem;
        font-size: 0.8rem;
    }
    
    .hero {
        padding: 40px 0;
    }
    
    .hero h2 {
        font-size: 1.3rem;
    }
    
    .hero .subtitle {
        font-size: 0.85rem;
    }
    
    .btn-primary {
        padding: 0.7rem 1.5rem;
        font-size: 0.9rem;
    }
    
    .about-card {
        padding: 1.2rem;
    }
    
    .about-card h3 {
        font-size: 1.1rem;
    }
    
    .about-card .esperanto-text {
        font-size: 0.85em;
    }
    
    .activity-date {
        padding: 0.8rem;
    }
    
    .activity-date .day {
        font-size: 1.8rem;
    }
    
    .activity-content {
        padding: 1.2rem;
    }
    
    .activity-content h3 {
        font-size: 1.1rem;
    }
    
    .activity-content .description {
        font-size: 0.9rem;
    }
    
    .tag {
        padding: 0.25rem 0.7rem;
        font-size: 0.8rem;
    }
    
    .country {
        padding: 0.4rem 0.6rem;
        font-size: 0.85rem;
    }
    
    .country .esperanto-text {
        display: none; /* 小屏幕上隐藏国家名的世界语 */
    }
    
    .gallery-image,
    .image-placeholder {
        height: 180px;
    }
    
    .gallery-caption {
        padding: 1rem;
    }
    
    .gallery-caption h4 {
        font-size: 1.1rem;
    }
    
    .contact-item {
        padding: 1rem;
        flex-direction: column;
        text-align: center;
    }
    
    .contact-item .icon {
        font-size: 1.8rem;
    }
    
    .join-card {
        padding: 1.5rem 1rem;
    }
    
    .join-card h3 {
        font-size: 1.3rem;
    }
    
    .esperanto-quote {
        font-size: 1.1rem;
    }
    
    .section-title {
        font-size: 1.4rem;
    }
    
    .zoom-info {
        padding: 0.8rem;
    }
    
    .zoom-info p {
        font-size: 0.85rem;
    }
    
    .footer {
        padding: 2rem 0;
    }
    
    .footer-logo {
        flex-direction: column;
        text-align: center;
    }
    
    .footer-logo > div {
        text-align: center;
    }
}

/* 超小屏幕 (小于 320px) */
@media (max-width: 320px) {
    .hero h2 {
        font-size: 1.1rem;
    }
    
    .nav a {
        padding: 0.25rem 0.5rem;
        font-size: 0.75rem;
    }
    
    .activity-date .day {
        font-size: 1.5rem;
    }
}

/* 大屏幕优化 (1200px 以上) */
@media (min-width: 1200px) {
    .container {
        max-width: 1400px;
    }
    
    .about-grid {
        grid-template-columns: repeat(4, 1fr);
    }
    
    .gallery-grid {
        grid-template-columns: repeat(3, 1fr);
    }
    
    .hero h2 {
        font-size: 3rem;
    }
    
    .section-title {
        font-size: 2.5rem;
    }
}

/* 横屏手机优化 */
@media (max-height: 500px) and (orientation: landscape) {
    .hero {
        padding: 40px 0;
    }
    
    .hero h2 {
        font-size: 1.5rem;
    }
    
    .header {
        position: relative; /* 横屏时不固定头部 */
    }
}

/* 高分辨率屏幕优化 */
@media (-webkit-min-device-pixel-ratio: 2), (min-resolution: 192dpi) {
    .hero {
        background-size: cover;
    }
}

/* 打印样式 */
@media print {
    .header,
    .nav,
    .btn-primary,
    .event-link {
        display: none;
    }
    
    .activity-card {
        break-inside: avoid;
        page-break-inside: avoid;
    }
    
    body {
        font-size: 12pt;
        line-height: 1.5;
    }
}