styles.css

/* ========================================
   Amarathon 网站样式 - 现代化设计
   参照旧版设计，使用渐变色和现代化布局
   ======================================== */

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

:root {
    /* 主色调 - 渐变紫粉色系 */
    --primary-gradient: linear-gradient(98deg, #2d62ff -24.99%, #be52ff 107.17%);
    --primary-blue: #2d62ff;
    --primary-purple: #be52ff;
    --primary-pink: #ec4899;
    
    /* AWS 品牌色 */
    --aws-orange: #FF9900;
    --aws-dark: #232F3E;
    
    /* 中性色 */
    --text-primary: #232f3f;
    --text-secondary: #545e6b;
    --text-tertiary: #556e8f;
    --text-light: #acb1b7;
    
    /* 背景色 */
    --bg-white: #ffffff;
    --bg-light: #fafafa;
    --bg-gradient-light: linear-gradient(6deg, rgba(255, 255, 255, 0) 55.47%, rgba(136, 189, 255, 0.2) 99.96%);
    --bg-gradient-purple: linear-gradient(205deg, rgba(247, 248, 251, 0.2) 60.71%, rgba(166, 169, 255, 0.2) 102.56%);
    
    /* 边框和分隔线 */
    --border-color: #e3e8ef;
    --border-light: #eaecf4;
    
    /* 间距 */
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 36px;
    --spacing-xl: 48px;
    --spacing-2xl: 72px;
    
    /* 圆角 */
    --radius-sm: 4px;
    --radius-md: 8px;
    --radius-lg: 12px;
    --radius-xl: 16px;
    --radius-2xl: 32px;
    --radius-full: 9999px;
}

body {
    font-family: 'Amazon Ember', 'Helvetica Neue', Roboto, Arial, 'Microsoft YaHei', 'PingFang SC', sans-serif;
    line-height: 1.6;
    color: var(--text-primary);
    background: var(--bg-light);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 var(--spacing-md);
}

/* ========================================
   顶部导航 - 已移除
   ======================================== */

/* ========================================
   活动横幅（全宽）
   ======================================== */
.banner-section-full {
    width: 100%;
    position: relative;
    background: transparent;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
}

.banner-section-full .banner-wrapper {
    max-width: 1200px;
    width: 100%;
    position: relative;
}

.banner-nav {
    position: absolute;
    top: 20px;
    left: 40px;
    z-index: 10;
    padding: 8px 16px;
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border-radius: 8px;
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.banner-logo {
    height: 40px;
    width: auto;
    display: block;
}

.banner-section-full .banner-wrapper #bannerContent {
    width: 100%;
    margin: 0;
    padding: 0;
}

.banner-section-full .banner-image {
    width: 100%;
    height: 15.625vw;
    display: block;
    object-fit: fill;
}

.banner-section-full .banner-placeholder {
    width: 100%;
    height: 15.625vw;
    min-height: 200px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    font-size: 48px;
    font-weight: 700;
}

/* ========================================
   年度选择器
   ======================================== */
.year-selector-section {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    position: sticky;
    top: 0;
    z-index: 999;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.year-tabs {
    display: flex;
    gap: 0;
    justify-content: center;
}

.year-btn {
    background: none;
    border: none;
    padding: 16px 32px;
    font-size: 16px;
    font-weight: 500;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.3s ease;
    border-bottom: 3px solid transparent;
    position: relative;
}

.year-btn:hover {
    background: rgba(45, 98, 255, 0.05);
    color: var(--text-primary);
}

.year-btn.active {
    color: var(--primary-blue);
    border-bottom-color: var(--primary-blue);
    background: var(--bg-white);
    font-weight: 700;
}

/* ========================================
   子导航
   ======================================== */
.sub-nav-section {
    background: var(--bg-white);
    border-bottom: 1px solid var(--border-light);
    position: sticky;
    top: 48px;
    z-index: 998;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
}

.sub-nav-tabs {
    display: flex;
    gap: 0;
    justify-content: center;
}

.sub-nav-btn {
    background: none;
    border: none;
    padding: 14px 40px;
    font-size: 14px;
    font-weight: 400;
    color: var(--text-secondary);
    cursor: pointer;
    transition: all 0.3s ease;
    border-bottom: 2px solid transparent;
}

.sub-nav-btn:hover {
    background: rgba(45, 98, 255, 0.05);
    color: var(--text-primary);
}

.sub-nav-btn.active {
    color: var(--text-primary);
    border-bottom: 2px solid;
    border-image: var(--primary-gradient) 1;
    font-weight: 700;
}

/* ========================================
   标签页内容
   ======================================== */
.tab-content {
    display: none;
}

.tab-content.active {
    display: block;
    animation: fadeIn 0.3s ease-in;
}

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

/* ========================================
   主内容区
   ======================================== */
main.container {
    padding: var(--spacing-2xl) var(--spacing-md);
    background: transparent;
}

.section {
    margin-bottom: var(--spacing-xl);
}

.section-header {
    background: var(--primary-gradient);
    padding: var(--spacing-md);
    border-radius: var(--radius-xl);
    margin-bottom: var(--spacing-lg);
    text-align: center;
    box-shadow: 0 4px 16px rgba(99, 102, 241, 0.2);
}

.section-header h2 {
    color: white;
    font-size: 30px;
    font-weight: 700;
    margin: 0;
    text-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    letter-spacing: 0.5px;
}

/* ========================================
   活动介绍
   ======================================== */
.introduction-section {
    margin-bottom: var(--spacing-lg);
}

.introduction-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.intro-title {
    font-size: 18px;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: var(--spacing-sm);
    font-weight: 600;
}

.intro-subtitle {
    font-size: 16px;
    line-height: 1.8;
    color: var(--text-primary);
    margin-bottom: 12px;
}

.intro-subtitle-en {
    font-size: 15px;
    line-height: 1.7;
    color: var(--text-secondary);
    font-style: italic;
    margin-bottom: var(--spacing-md);
}

.intro-theme {
    background: var(--primary-gradient);
    padding: var(--spacing-md);
    border-radius: var(--radius-md);
    color: white;
    margin-top: 20px;
}

.theme-title {
    font-size: 24px;
    font-weight: 700;
    margin-bottom: 12px;
    color: white;
}

.theme-description {
    font-size: 16px;
    line-height: 1.7;
    color: white;
    opacity: 0.95;
}

.intro-terms {
    margin-top: var(--spacing-md);
    text-align: center;
}

.intro-terms .terms-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: white;
    text-decoration: none;
    font-size: 15px;
    font-weight: 500;
    padding: 12px 28px;
    background: var(--primary-gradient);
    border-radius: var(--radius-md);
    border: none;
    transition: all 0.3s ease;
    box-shadow: 0 4px 12px rgba(99, 102, 241, 0.3);
}

.intro-terms .terms-link:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
    filter: brightness(1.1);
}

.intro-images {
    margin-top: var(--spacing-md);
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: var(--spacing-sm);
}

.intro-image {
    width: 100%;
    height: auto;
    border-radius: var(--radius-md);
    object-fit: cover;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.intro-image:hover {
    transform: scale(1.02);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
}

/* 单张图片时全宽显示 */
.intro-images:has(.intro-image:only-child) {
    grid-template-columns: 1fr;
}

/* 两张图片时各占一半 */
.intro-images:has(.intro-image:nth-child(2):last-child) {
    grid-template-columns: repeat(2, 1fr);
}

/* ========================================
   直播安排
   ======================================== */
.live-schedule-container {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.live-schedule-card {
    background: var(--primary-gradient);
    border-radius: var(--radius-xl);
    padding: var(--spacing-lg);
    color: white;
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.3);
    border: 3px solid rgba(255, 255, 255, 0.2);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.live-schedule-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 12px 32px rgba(99, 102, 241, 0.4);
}

.card-icon {
    font-size: 32px;
    margin-bottom: 12px;
}

.card-title {
    font-size: 24px;
    font-weight: 600;
    margin-bottom: 20px;
    color: white;
}

.event-dates {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.event-date-item {
    display: flex;
    align-items: baseline;
    gap: var(--spacing-xs);
    font-size: 15px;
    line-height: 1.6;
}

.timezone-label {
    font-weight: 600;
    min-width: 120px;
}

.datetime {
    font-weight: 400;
}

.card-content {
    font-size: 15px;
    line-height: 1.8;
}

.description-cn {
    margin-bottom: 12px;
}

.description-en {
    opacity: 0.9;
    font-style: italic;
}

.details {
    margin-top: var(--spacing-sm);
    font-weight: 600;
}

.interaction-links {
    margin-top: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    flex-wrap: wrap;
}

.link-button {
    display: inline-block;
    padding: 10px 24px;
    background: rgba(255, 255, 255, 0.2);
    border: 2px solid rgba(255, 255, 255, 0.3);
    border-radius: var(--radius-md);
    color: white;
    text-decoration: none;
    font-weight: 600;
    transition: all 0.3s ease;
}

.link-button:hover {
    background: rgba(255, 255, 255, 0.3);
    transform: translateY(-2px);
}

.twitter-handle {
    font-weight: 600;
}

.terms-link {
    color: white;
    text-decoration: underline;
    opacity: 0.8;
    transition: opacity 0.3s ease;
}

.terms-link:hover {
    opacity: 1;
}

/* ========================================
   直播状态
   ======================================== */
.live-status-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    text-align: center;
}

.status-buttons {
    display: flex;
    justify-content: center;
    gap: var(--spacing-sm);
    margin-bottom: var(--spacing-md);
}

.status-btn {
    padding: 12px 32px;
    border-radius: var(--radius-full);
    font-size: 16px;
    font-weight: 700;
    border: none;
    cursor: pointer;
    transition: all 0.3s ease;
}

.status-btn.disabled {
    background: #bec4da;
    color: white;
    cursor: not-allowed;
}

.replay-info, .community-links, .terms-info {
    margin-top: var(--spacing-sm);
}

.replay-link, .community-link {
    color: var(--primary-blue);
    text-decoration: none;
    font-weight: 600;
    transition: color 0.3s ease;
}

.replay-link:hover, .community-link:hover {
    color: var(--primary-purple);
    text-decoration: underline;
}

/* ========================================
   合作伙伴
   ======================================== */
.partners-container {
    display: flex;
    flex-direction: column;
    gap: 60px;
}

.partner-category {
    text-align: center;
}

.partner-title {
    color: var(--text-primary);
    font-size: 30px;
    font-weight: 700;
    margin-bottom: var(--spacing-md);
}

.partner-logos {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 60px;
    flex-wrap: wrap;
}

.partner-logo-link {
    transition: all 0.3s ease;
}

.partner-logo-link:hover {
    transform: scale(1.05);
    opacity: 0.8;
}

.partner-logo {
    height: auto;
    max-width: 200px;
    object-fit: contain;
}

/* ========================================
   活动召集
   ======================================== */
.announcement-card {
    background: var(--bg-white);
    padding: var(--spacing-lg);
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.announcement-card h3 {
    color: var(--text-primary);
    font-size: 24px;
    font-weight: 700;
    margin-bottom: var(--spacing-sm);
}

.announcement-card .date {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: var(--spacing-sm);
}

.announcement-card .description {
    color: var(--text-secondary);
    line-height: 1.8;
}

/* ========================================
   活动图片
   ======================================== */
.gallery-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: var(--spacing-md);
}

.gallery-item-link {
    text-decoration: none;
    color: inherit;
}

.gallery-item {
    background: var(--bg-white);
    border-radius: var(--radius-lg);
    overflow: hidden;
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
}

.gallery-item:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.12);
}

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

.gallery-placeholder {
    width: 100%;
    height: 250px;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    font-size: 64px;
}

.gallery-caption {
    padding: var(--spacing-sm);
    color: var(--text-primary);
    font-weight: 600;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.read-more {
    color: var(--primary-blue);
    font-size: 14px;
}

/* ========================================
   演讲议程
   ======================================== */
.agenda-section {
    position: relative;
}

.agenda-filters {
    background: linear-gradient(135deg, #f8f9ff 0%, #f0f4ff 100%);
    padding: var(--spacing-md);
    border-radius: var(--radius-lg);
    margin-bottom: var(--spacing-md);
    display: flex;
    gap: 20px;
    flex-wrap: wrap;
    align-items: center;
    border: 2px solid #e0e7ff;
}

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

.filter-group label {
    font-size: 14px;
    font-weight: 600;
    color: #4b5563;
    white-space: nowrap;
}

.filter-group select,
.filter-group input {
    padding: 8px 16px;
    border: 2px solid #e0e7ff;
    border-radius: var(--radius-md);
    font-size: 14px;
    background: white;
    transition: all 0.3s ease;
}

.filter-group select:focus,
.filter-group input:focus {
    outline: none;
    border-color: var(--primary-blue);
    box-shadow: 0 0 0 3px rgba(45, 98, 255, 0.1);
}

.filter-group input {
    min-width: 250px;
}

.agenda-cards {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-md);
}

.agenda-card {
    padding: 10px;
    border-radius: var(--radius-lg);
    background: var(--primary-gradient);
    position: relative;
    transition: all 0.3s ease;
}

.agenda-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.3);
}

.agenda-badge {
    position: absolute;
    left: 0;
    top: 0;
    border-radius: var(--radius-lg) 0;
    background: linear-gradient(0deg, #585eff, #585eff);
    display: flex;
    padding: 6px var(--spacing-sm);
    justify-content: center;
    align-items: center;
    color: white;
    font-size: 14px;
    font-weight: 700;
    line-height: 22px;
    z-index: 1;
}

.agenda-badge.level-200 {
    background: linear-gradient(135deg, #10b981 0%, #059669 100%);
}

.agenda-badge.level-300 {
    background: linear-gradient(135deg, #f59e0b 0%, #d97706 100%);
}

.agenda-badge.level-400 {
    background: linear-gradient(135deg, #ef4444 0%, #dc2626 100%);
}

.agenda-card-content {
    background: white;
    border-radius: var(--radius-md);
    padding: var(--spacing-lg) 30px 0;
}

.agenda-time-section {
    display: flex;
    gap: var(--spacing-md);
    margin-bottom: var(--spacing-md);
}

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

.timezone-label {
    color: var(--text-light);
    font-size: 12px;
    font-weight: 400;
    line-height: 14px;
}

.time-value {
    color: #8837f3;
    font-size: 14px;
    font-weight: 700;
    line-height: 18px;
    background: var(--primary-gradient);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.language-badge {
    display: flex;
    align-items: center;
    gap: 4px;
    padding: 4px 12px;
    background: rgba(45, 98, 255, 0.1);
    border-radius: var(--radius-full);
    font-size: 12px;
    font-weight: 600;
    color: var(--primary-blue);
}

.language-icon {
    font-size: 16px;
}

.agenda-right-section {
    flex: 1;
}

.agenda-desc-section {
    margin-bottom: var(--spacing-md);
}

.session-title {
    color: var(--text-primary);
    font-size: 24px;
    font-weight: 700;
    line-height: 32px;
    margin-bottom: var(--spacing-sm);
}

.title-cn {
    display: block;
    font-size: 20px;
    margin-top: 8px;
    color: var(--text-secondary);
}

.session-summary-container {
    position: relative;
}

.session-summary {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 400;
    line-height: 22px;
    white-space: pre-line;
    max-height: none;
    overflow: visible;
    transition: max-height 0.3s ease;
}

.session-summary.collapsed {
    max-height: 200px;
    overflow: hidden;
    position: relative;
}

.session-summary.collapsed::after {
    content: '';
    position: absolute;
    bottom: 0;
    left: 0;
    right: 0;
    height: 60px;
    background: linear-gradient(to bottom, transparent, white);
}

.toggle-summary {
    background: none;
    border: none;
    color: var(--primary-blue);
    font-weight: 600;
    cursor: pointer;
    padding: 8px 0;
    margin-top: 8px;
    transition: color 0.3s ease;
}

.toggle-summary:hover {
    color: var(--primary-purple);
}

.agenda-bottom-section {
    border-top: 1px solid var(--border-color);
    padding: var(--spacing-md) 0;
}

.speaker-info {
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
}

.speaker-photo {
    width: 46px;
    height: 46px;
    border-radius: 50%;
    object-fit: cover;
}

.speaker-avatar {
    width: 46px;
    height: 46px;
    border-radius: 50%;
    background: var(--primary-gradient);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 20px;
    font-weight: 700;
}

.speaker-details {
    flex: 1;
}

.speaker-name {
    color: var(--text-primary);
    font-size: 18px;
    font-weight: 700;
    line-height: 24px;
}

.speaker-country {
    color: #555eff;
    font-size: 14px;
    font-weight: 700;
    line-height: 22px;
}

.speaker-title {
    color: var(--text-secondary);
    font-size: 14px;
    font-weight: 400;
    line-height: 22px;
}

.speaker-social {
    display: flex;
    gap: var(--spacing-sm);
    align-items: center;
}

.social-link {
    color: var(--text-secondary);
    transition: all 0.3s ease;
}

.social-link:hover {
    color: var(--primary-blue);
    transform: scale(1.1);
}

.social-link svg {
    display: block;
}

.speakers-list {
    display: flex;
    flex-direction: column;
    gap: var(--spacing-sm);
}

.filter-result-hint {
    text-align: center;
    padding: var(--spacing-lg);
    color: var(--text-secondary);
    font-size: 16px;
}

/* ========================================
   组委会
   ======================================== */
.committee-section {
    margin-bottom: 60px;
}

.committee-nav {
    display: flex;
    align-items: center;
    justify-content: space-between;
    width: 100%;
    margin: 40px 0 60px;
    background: white;
    border-radius: var(--radius-2xl);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

.committee-nav-btn {
    flex: 1;
    padding: 14px 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    cursor: pointer;
    background: none;
    border: none;
    font-family: inherit;
    outline: none;
    transition: all 0.3s ease;
    border-radius: var(--radius-2xl);
}

.committee-nav-btn:hover {
    background: rgba(45, 98, 255, 0.05);
}

.committee-nav-btn.active {
    background: var(--primary-gradient);
}

.committee-nav-btn.active:hover {
    opacity: 0.95;
}

.committee-nav-btn .nav-subtitle {
    font-size: 12px;
    color: var(--text-tertiary);
}

.committee-nav-btn.active .nav-subtitle {
    color: rgba(255, 255, 255, 0.8);
}

.committee-nav-btn:not(.active) {
    color: var(--text-primary);
    font-size: 14px;
    font-weight: 400;
}

.committee-nav-btn.active {
    color: white;
    font-weight: 700;
}

.committee-section-header {
    text-align: center;
    margin-bottom: 40px;
}

.committee-section-header .section-title {
    font-size: 32px;
    font-weight: 700;
    color: var(--text-primary);
    margin-bottom: 8px;
}

.committee-section-header .section-subtitle {
    font-size: 16px;
    color: var(--text-tertiary);
}

.committee-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.committee-card {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 10px;
    border-radius: var(--radius-lg);
    background: var(--primary-gradient);
    transition: all 0.3s ease;
}

.committee-card:hover {
    transform: translateY(-4px);
    box-shadow: 0 8px 24px rgba(99, 102, 241, 0.3);
}

.committee-photo {
    width: 100%;
    height: auto;
    border-radius: var(--radius-md);
    object-fit: cover;
}

.committee-avatar {
    width: 100%;
    height: 200px;
    border-radius: var(--radius-md);
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 64px;
    font-weight: 700;
}

.committee-info {
    background: white;
    padding: 20px;
    border-radius: var(--radius-md);
    flex: 1;
}

.committee-name {
    color: var(--text-primary);
    font-size: 20px;
    font-weight: 700;
    line-height: 28px;
    margin-bottom: 10px;
}

.committee-position {
    color: #555eff;
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 4px;
}

.committee-position-en {
    color: var(--text-secondary);
    font-size: 12px;
    font-style: italic;
}

.committee-title {
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: 8px;
}

.committee-desc,
.committee-desc-en,
.committee-bio,
.committee-job,
.committee-job-en {
    margin-top: 10px;
    color: var(--text-secondary);
    font-size: 14px;
    line-height: 22px;
}

.committee-social {
    display: flex;
    gap: var(--spacing-sm);
    padding: 10px 20px;
    background: rgba(255, 255, 255, 0.5);
    border-radius: var(--radius-md);
}

.social-icon {
    transition: all 0.3s ease;
}

.social-icon:hover {
    transform: scale(1.1);
    opacity: 0.7;
}

.social-icon img {
    width: 18px;
    height: auto;
}

/* ========================================
   活动条款 PDF 查看器
   ======================================== */
.terms-section {
    margin-bottom: var(--spacing-xl);
}

.terms-pdf-container {
    background: white;
    border-radius: var(--radius-md);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
    overflow: hidden;
    position: relative;
}

.terms-pdf-viewer {
    width: 100%;
    height: 800px;
    border: none;
    display: block;
    background: white;
}

.terms-fallback {
    padding: var(--spacing-md);
    text-align: center;
    background: #f8f9ff;
    border-top: 1px solid #e0e7ff;
}

.terms-fallback p {
    margin: 8px 0;
    color: var(--text-secondary);
    font-size: 14px;
}

.terms-fallback a {
    color: var(--aws-orange);
    text-decoration: none;
    font-weight: 500;
}

.terms-fallback a:hover {
    text-decoration: underline;
}

/* ========================================
   空状态
   ======================================== */
.empty-state {
    text-align: center;
    padding: var(--spacing-2xl);
    color: var(--text-secondary);
    font-size: 16px;
    background: white;
    border-radius: var(--radius-lg);
    box-shadow: 0 2px 12px rgba(0, 0, 0, 0.08);
}

/* ========================================
   加载状态
   ======================================== */
.loading-spinner {
    text-align: center;
    padding: var(--spacing-2xl);
    font-size: 24px;
    color: var(--primary-blue);
    animation: spin 1s linear infinite;
}

@keyframes spin {
    from {
        transform: rotate(0deg);
    }
    to {
        transform: rotate(360deg);
    }
}

/* ========================================
   通知系统
   ======================================== */
.notification {
    position: fixed;
    top: 80px;
    right: 20px;
    padding: var(--spacing-sm) var(--spacing-md);
    border-radius: var(--radius-md);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    z-index: 10000;
    animation: slideIn 0.3s ease-out;
}

@keyframes slideIn {
    from {
        transform: translateX(400px);
        opacity: 0;
    }
    to {
        transform: translateX(0);
        opacity: 1;
    }
}

.notification-success {
    background: #10b981;
    color: white;
}

.notification-error {
    background: #ef4444;
    color: white;
}

.notification-warning {
    background: #f59e0b;
    color: white;
}

.notification-info {
    background: #3b82f6;
    color: white;
}

/* ========================================
   页脚
   ======================================== */
.footer {
    background: var(--aws-dark);
    color: white;
    padding: var(--spacing-lg) 0;
    margin-top: var(--spacing-2xl);
}

.footer-content {
    text-align: center;
}

.footer-content p {
    margin: 0;
    opacity: 0.8;
    font-size: 14px;
}

/* ========================================
   响应式设计 - 平板
   ======================================== */
@media screen and (max-width: 1199px) {
    .container {
        padding: 0 var(--spacing-sm);
    }
    
    .banner-section-full .banner-image {
        height: 48.828125vw;
    }
    
    .banner-section-full .banner-placeholder {
        height: 48.828125vw;
        min-height: 250px;
        font-size: 40px;
    }
    
    .banner-nav {
        top: 15px;
        left: 20px;
        padding: 6px 12px;
    }
    
    .banner-logo {
        height: 32px;
    }
    
    .section-header h2 {
        font-size: 24px;
    }
    
    .gallery-grid {
        grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    }
    
    .committee-grid {
        grid-template-columns: 1fr;
    }
    
    .partner-logos {
        gap: 40px;
    }
    
    .agenda-filters {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-group {
        flex-direction: column;
        align-items: stretch;
    }
    
    .filter-group input {
        min-width: 100%;
    }
}

/* ========================================
   响应式设计 - 手机
   ======================================== */
@media screen and (max-width: 767px) {
    :root {
        --spacing-xs: 6px;
        --spacing-sm: 12px;
        --spacing-md: 16px;
        --spacing-lg: 24px;
        --spacing-xl: 32px;
        --spacing-2xl: 48px;
    }
    
    .banner-section-full .banner-image {
        height: 74.6666666667vw;
    }
    
    .banner-section-full .banner-placeholder {
        height: 74.6666666667vw;
        min-height: 200px;
        font-size: 32px;
    }
    
    .banner-nav {
        top: 10px;
        left: 10px;
        padding: 4px 8px;
    }
    
    .banner-logo {
        height: 28px;
    }
    
    .year-btn {
        padding: 12px 20px;
        font-size: 14px;
    }
    
    .sub-nav-btn {
        padding: 12px 20px;
        font-size: 13px;
    }
    
    main.container {
        padding: var(--spacing-lg) var(--spacing-sm);
    }
    
    .section-header h2 {
        font-size: 20px;
    }
    
    .introduction-card {
        padding: var(--spacing-sm);
    }
    
    .intro-title {
        font-size: 16px;
    }
    
    .intro-subtitle {
        font-size: 14px;
    }
    
    .intro-subtitle-en {
        font-size: 13px;
    }
    
    .theme-title {
        font-size: 20px;
    }
    
    .theme-description {
        font-size: 14px;
    }
    
    .intro-images {
        grid-template-columns: 1fr;
        gap: var(--spacing-xs);
    }
    
    .live-schedule-card {
        padding: var(--spacing-sm);
    }
    
    .card-title {
        font-size: 20px;
    }
    
    .card-content {
        font-size: 14px;
    }
    
    .gallery-grid {
        grid-template-columns: 1fr;
    }
    
    .gallery-image,
    .gallery-placeholder {
        height: 200px;
    }
    
    .partner-title {
        font-size: 24px;
    }
    
    .partner-logos {
        gap: 30px;
    }
    
    .partner-logo {
        max-width: 150px;
    }
    
    .announcement-card h3 {
        font-size: 20px;
    }
    
    .agenda-card {
        padding: 8px;
    }
    
    .agenda-badge {
        font-size: 12px;
        padding: 4px 12px;
    }
    
    .agenda-card-content {
        padding: var(--spacing-sm);
    }
    
    .agenda-time-section {
        flex-direction: column;
        gap: 12px;
    }
    
    .session-title {
        font-size: 18px;
        line-height: 26px;
    }
    
    .title-cn {
        font-size: 16px;
    }
    
    .session-summary {
        font-size: 13px;
        line-height: 20px;
    }
    
    .speaker-name {
        font-size: 16px;
    }
    
    .speaker-title {
        font-size: 13px;
    }
    
    .committee-nav {
        flex-direction: column;
        margin: 20px 0 30px;
    }
    
    .committee-nav-btn {
        padding: 12px 20px;
        border-radius: 0;
    }
    
    .committee-nav-btn:first-child {
        border-radius: var(--radius-2xl) var(--radius-2xl) 0 0;
    }
    
    .committee-nav-btn:last-child {
        border-radius: 0 0 var(--radius-2xl) var(--radius-2xl);
    }
    
    .committee-section-header .section-title {
        font-size: 24px;
    }
    
    .committee-section-header .section-subtitle {
        font-size: 14px;
    }
    
    .committee-grid {
        grid-template-columns: 1fr;
        gap: var(--spacing-sm);
    }
    
    .committee-name {
        font-size: 18px;
    }
    
    .committee-info {
        padding: var(--spacing-sm);
    }
    
    .terms-pdf-viewer {
        height: 600px;
    }
    
    .notification {
        right: 10px;
        left: 10px;
        top: 70px;
    }
}

/* ========================================
   打印样式
   ======================================== */
@media print {
    .year-selector-section,
    .sub-nav-section,
    .footer {
        display: none;
    }
    
    .section {
        page-break-inside: avoid;
    }
    
    .agenda-card,
    .committee-card {
        page-break-inside: avoid;
    }
}

/* ========================================
   辅助类
   ======================================== */
.text-center {
    text-align: center;
}

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

.text-right {
    text-align: right;
}

.mt-0 { margin-top: 0; }
.mt-1 { margin-top: var(--spacing-xs); }
.mt-2 { margin-top: var(--spacing-sm); }
.mt-3 { margin-top: var(--spacing-md); }
.mt-4 { margin-top: var(--spacing-lg); }

.mb-0 { margin-bottom: 0; }
.mb-1 { margin-bottom: var(--spacing-xs); }
.mb-2 { margin-bottom: var(--spacing-sm); }
.mb-3 { margin-bottom: var(--spacing-md); }
.mb-4 { margin-bottom: var(--spacing-lg); }

.hidden {
    display: none !important;
}

.visible {
    display: block !important;
}

/* ========================================
   滚动条样式
   ======================================== */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: #f1f1f1;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb {
    background: #888;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #555;
}

/* ========================================
   焦点样式（无障碍）
   ======================================== */
*:focus-visible {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
}

button:focus-visible,
a:focus-visible {
    outline: 2px solid var(--primary-blue);
    outline-offset: 2px;
    box-shadow: 0 0 0 4px rgba(45, 98, 255, 0.2);
}

/* ========================================
   动画效果
   ======================================== */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in-up {
    animation: fadeInUp 0.6s ease-out;
}

@keyframes pulse {
    0%, 100% {
        opacity: 1;
    }
    50% {
        opacity: 0.5;
    }
}

.pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* ========================================
   结束
   ======================================== */