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

:root {
    /* 文化典雅配色 */
    --primary-gold: #D4AF37;
    --dark-bronze: #8B4513;
    --ink-black: #1A1A1A;
    --paper-white: #F5F1E8;
    --soft-gray: #E5E5E5;
    --accent-red: #C41E3A;
    --royal-blue: #1E3A8A;
    
    /* 字体 */
    --font-zh: 'Noto Serif SC', serif;
    --font-en: 'Inter', sans-serif;
    
    /* 间距 */
    --spacing-xs: 8px;
    --spacing-sm: 16px;
    --spacing-md: 24px;
    --spacing-lg: 32px;
    --spacing-xl: 48px;
    
    /* 阴影 */
    --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.1);
    --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.15);
    --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.2);
    
    /* 动画 */
    --transition-fast: 0.2s ease;
    --transition-normal: 0.3s ease;
    --transition-slow: 0.5s ease;
}

body {
    font-family: var(--font-zh);
    background: linear-gradient(135deg, var(--paper-white) 0%, #FFF 100%);
    color: var(--ink-black);
    line-height: 1.6;
    min-height: 100vh;
}

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

/* ============================================
   页面切换
============================================ */
.page {
    display: none;
    opacity: 0;
    animation: fadeOut var(--transition-normal) forwards;
}

.page.active {
    display: block;
    animation: fadeIn var(--transition-normal) forwards;
}

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

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

/* ============================================
   返回按钮
============================================ */
.back-btn {
    background: rgba(255, 255, 255, 0.9);
    border: 1px solid var(--soft-gray);
    padding: var(--spacing-xs) var(--spacing-sm);
    border-radius: 24px;
    cursor: pointer;
    font-size: 14px;
    color: var(--ink-black);
    transition: all var(--transition-fast);
    margin-bottom: var(--spacing-md);
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

.back-btn:hover {
    background: var(--primary-gold);
    color: white;
    transform: translateX(-4px);
}

/* ============================================
   入口页面
============================================ */
.hero-section {
    text-align: center;
    padding: var(--spacing-xl) 0;
    min-height: 80vh;
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
}

.app-title {
    margin-bottom: var(--spacing-md);
}

.title-en {
    display: block;
    font-family: var(--font-en);
    font-size: 3.5rem;
    font-weight: 700;
    background: linear-gradient(135deg, var(--primary-gold), var(--dark-bronze));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: var(--spacing-sm);
}

.title-zh {
    display: block;
    font-size: 2rem;
    font-weight: 600;
    color: var(--ink-black);
    letter-spacing: 4px;
}

.app-subtitle {
    font-size: 1.5rem;
    color: var(--dark-bronze);
    margin-bottom: var(--spacing-sm);
}

.app-description {
    font-size: 1.1rem;
    color: #666;
    margin-bottom: var(--spacing-xl);
    max-width: 600px;
}

.upload-btn {
    background: linear-gradient(135deg, var(--primary-gold), var(--dark-bronze));
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: 50px;
    font-size: 1.3rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
    box-shadow: var(--shadow-md);
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin: 0 auto var(--spacing-lg);
}

.upload-btn:hover {
    transform: translateY(-4px);
    box-shadow: var(--shadow-lg);
}

.btn-icon {
    display: flex;
    gap: 8px;
    font-size: 1.5rem;
}

.feature-tags {
    display: flex;
    gap: var(--spacing-sm);
    justify-content: center;
    flex-wrap: wrap;
}

.tag {
    background: white;
    padding: var(--spacing-xs) var(--spacing-md);
    border-radius: 20px;
    font-size: 0.9rem;
    color: var(--dark-bronze);
    box-shadow: var(--shadow-sm);
    display: flex;
    align-items: center;
    gap: 8px;
}

/* ============================================
   上传页面
============================================ */
.upload-section {
    max-width: 600px;
    margin: var(--spacing-lg) auto;
    text-align: center;
}

.section-title {
    font-size: 2rem;
    color: var(--ink-black);
    margin-bottom: var(--spacing-sm);
}

.upload-hint {
    background: #FFF3CD;
    color: #856404;
    padding: var(--spacing-sm);
    border-radius: 8px;
    margin-bottom: var(--spacing-lg);
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.upload-preview {
    background: white;
    border: 3px dashed var(--soft-gray);
    border-radius: 16px;
    padding: var(--spacing-xl);
    margin-bottom: var(--spacing-lg);
    min-height: 300px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all var(--transition-normal);
}

.upload-preview.has-image {
    border-color: var(--primary-gold);
    border-style: solid;
}

.preview-placeholder {
    text-align: center;
    color: #999;
}

.preview-placeholder i {
    font-size: 4rem;
    margin-bottom: var(--spacing-sm);
}

.upload-preview img {
    max-width: 100%;
    max-height: 300px;
    border-radius: 8px;
    box-shadow: var(--shadow-md);
}

.upload-options {
    display: flex;
    gap: var(--spacing-md);
    justify-content: center;
    margin-bottom: var(--spacing-lg);
}

.upload-option-btn {
    flex: 1;
    max-width: 250px;
    background: white;
    border: 2px solid var(--primary-gold);
    padding: var(--spacing-lg) var(--spacing-md);
    border-radius: 16px;
    cursor: pointer;
    transition: all var(--transition-fast);
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: var(--spacing-sm);
    font-size: 1.1rem;
    font-weight: 600;
    color: var(--dark-bronze);
}

.upload-option-btn:hover {
    background: var(--primary-gold);
    color: white;
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.upload-option-btn i {
    font-size: 2.5rem;
}

.upload-option-btn input {
    display: none;
}

.confirm-btn {
    background: var(--primary-gold);
    color: white;
    border: none;
    padding: var(--spacing-md) var(--spacing-xl);
    border-radius: 50px;
    font-size: 1.2rem;
    font-weight: 600;
    cursor: pointer;
    transition: all var(--transition-normal);
}

.confirm-btn:disabled {
    background: var(--soft-gray);
    cursor: not-allowed;
    opacity: 0.5;
}

.confirm-btn:not(:disabled):hover {
    background: var(--dark-bronze);
    transform: translateY(-2px);
    box-shadow: var(--shadow-md);
}

/* ============================================
   详情页
============================================ */
.detail-header {
    display: flex;
    gap: var(--spacing-lg);
    align-items: center;
    background: white;
    padding: var(--spacing-lg);
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    margin-bottom: var(--spacing-lg);
}

.relic-image {
    flex-shrink: 0;
    width: 200px;
    height: 200px;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

.relic-image img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.relic-info {
    flex: 1;
}

.relic-title {
    font-size: 2.5rem;
    color: var(--ink-black);
    margin-bottom: var(--spacing-sm);
    font-weight: 700;
}

.relic-meta {
    display: flex;
    gap: var(--spacing-md);
    color: #666;
    font-size: 1rem;
}

.relic-meta span {
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

/* ============================================
   模块卡片
============================================ */
.module-card {
    background: white;
    border-radius: 16px;
    box-shadow: var(--shadow-md);
    margin-bottom: var(--spacing-lg);
    overflow: hidden;
    transition: all var(--transition-normal);
}

.module-card:hover {
    box-shadow: var(--shadow-lg);
}

.card-header {
    background: linear-gradient(135deg, var(--primary-gold), var(--dark-bronze));
    color: white;
    padding: var(--spacing-md) var(--spacing-lg);
}

.card-header h2 {
    font-size: 1.5rem;
    display: flex;
    align-items: center;
    gap: var(--spacing-sm);
    margin-bottom: 0;
}

.timeline-subtitle {
    margin-top: var(--spacing-xs);
    font-size: 0.9rem;
    opacity: 0.9;
}

.card-body {
    padding: var(--spacing-lg);
}

/* ============================================
   模块1: 英文翻译
============================================ */
.translation-main {
    background: linear-gradient(135deg, #FFF9E6, #FFF);
    padding: var(--spacing-lg);
    border-radius: 12px;
    margin-bottom: var(--spacing-md);
    border-left: 4px solid var(--primary-gold);
}

.translation-main .label {
    font-family: var(--font-en);
    font-size: 1rem;
    color: #666;
    display: block;
    margin-bottom: var(--spacing-xs);
}

.translation-text {
    font-family: var(--font-en);
    font-size: 2rem;
    font-weight: 700;
    color: var(--dark-bronze);
    display: block;
}

.translation-supplement {
    background: #F8F9FA;
    padding: var(--spacing-md);
    border-radius: 8px;
    font-family: var(--font-en);
    font-size: 1rem;
    line-height: 1.8;
    color: #555;
}

/* ============================================
   模块2: 解读与历史传承
============================================ */
.interpretation-section,
.heritage-section {
    margin-bottom: var(--spacing-lg);
}

.interpretation-section:last-child,
.heritage-section:last-child {
    margin-bottom: 0;
}

.interpretation-section h3,
.heritage-section h3 {
    font-size: 1.3rem;
    color: var(--dark-bronze);
    margin-bottom: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--primary-gold);
}

.interpretation-list {
    list-style: none;
    padding: 0;
}

.interpretation-list li {
    padding: var(--spacing-sm);
    margin-bottom: var(--spacing-sm);
    background: #F8F9FA;
    border-radius: 8px;
    border-left: 4px solid var(--primary-gold);
}

.interpretation-list strong {
    color: var(--dark-bronze);
}

.heritage-section p {
    font-size: 1.05rem;
    line-height: 1.8;
    color: #444;
}

.heritage-section strong {
    color: var(--dark-bronze);
    font-weight: 600;
}

/* ============================================
   模块3: 时间轴
============================================ */
.timeline-labels {
    display: flex;
    justify-content: space-between;
    margin-bottom: var(--spacing-lg);
}

.timeline-label {
    flex: 1;
    text-align: center;
    font-size: 1.2rem;
    font-weight: 600;
    padding: var(--spacing-sm);
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-xs);
}

.china-label {
    background: linear-gradient(135deg, #FFE5E5, #FFF);
    color: var(--accent-red);
}

.britain-label {
    background: linear-gradient(135deg, #E5F0FF, #FFF);
    color: var(--royal-blue);
}

.timeline-container {
    margin-top: var(--spacing-lg);
}

.timeline-axis {
    position: relative;
    padding: var(--spacing-xl) 0;
}

.timeline-scale {
    display: flex;
    justify-content: space-between;
    padding: 0 40px;
    margin-bottom: var(--spacing-sm);
    font-family: var(--font-en);
    font-weight: 600;
    color: #999;
}

.timeline-track {
    display: flex;
    justify-content: space-around;
    align-items: center;
    padding: var(--spacing-lg) var(--spacing-md);
    position: relative;
}

.china-track {
    background: linear-gradient(to right, rgba(212, 175, 55, 0.1), rgba(212, 175, 55, 0.05));
    border-radius: 12px 12px 0 0;
}

.britain-track {
    background: linear-gradient(to right, rgba(30, 58, 138, 0.1), rgba(30, 58, 138, 0.05));
    border-radius: 0 0 12px 12px;
}

.timeline-divider {
    height: 3px;
    background: linear-gradient(to right, var(--primary-gold), var(--soft-gray), var(--royal-blue));
    margin: 0;
}

.timeline-period {
    text-align: center;
    cursor: pointer;
    transition: all var(--transition-normal);
    position: relative;
    padding: var(--spacing-sm);
    border-radius: 12px;
}

.timeline-period:hover {
    transform: scale(1.05);
    background: rgba(255, 255, 255, 0.8);
}

.timeline-period.highlight {
    animation: pulse 2s infinite;
}

@keyframes pulse {
    0%, 100% {
        box-shadow: 0 0 0 0 rgba(212, 175, 55, 0.7);
    }
    50% {
        box-shadow: 0 0 0 15px rgba(212, 175, 55, 0);
    }
}

.period-avatar {
    width: 80px;
    height: 80px;
    border-radius: 50%;
    overflow: hidden;
    margin: 0 auto var(--spacing-xs);
    border: 4px solid white;
    box-shadow: var(--shadow-md);
    transition: all var(--transition-fast);
}

.timeline-period:hover .period-avatar {
    transform: scale(1.1);
    border-color: var(--primary-gold);
}

.period-avatar img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.period-label {
    font-size: 0.85rem;
    font-weight: 600;
    color: var(--ink-black);
    display: block;
}

.highlight-icon {
    position: absolute;
    top: 0;
    right: 0;
    color: var(--primary-gold);
    font-size: 1.5rem;
    animation: rotate 3s linear infinite;
}

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

/* ============================================
   Modal 弹窗
============================================ */
.modal {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1000;
    justify-content: center;
    align-items: center;
    backdrop-filter: blur(5px);
}

.modal.active {
    display: flex;
    animation: fadeIn var(--transition-normal) forwards;
}

.modal-content {
    background: white;
    border-radius: 16px;
    padding: var(--spacing-xl);
    max-width: 600px;
    width: 90%;
    max-height: 80vh;
    overflow-y: auto;
    box-shadow: var(--shadow-lg);
    position: relative;
    animation: slideUp var(--transition-normal) forwards;
}

@keyframes slideUp {
    from {
        transform: translateY(50px);
        opacity: 0;
    }
    to {
        transform: translateY(0);
        opacity: 1;
    }
}

.modal-close {
    position: absolute;
    top: var(--spacing-sm);
    right: var(--spacing-sm);
    background: var(--soft-gray);
    border: none;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 1.2rem;
    transition: all var(--transition-fast);
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    background: var(--accent-red);
    color: white;
    transform: rotate(90deg);
}

.modal-header {
    margin-bottom: var(--spacing-md);
}

.modal-title {
    font-size: 1.8rem;
    color: var(--ink-black);
    margin-bottom: var(--spacing-sm);
}

.modal-subtitle {
    font-size: 1.1rem;
    color: #666;
}

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

.modal-section h3 {
    font-size: 1.2rem;
    color: var(--dark-bronze);
    margin-bottom: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--primary-gold);
}

.modal-section ul {
    list-style: none;
    padding: 0;
}

.modal-section li {
    padding: var(--spacing-xs) 0;
    padding-left: var(--spacing-md);
    border-left: 3px solid var(--primary-gold);
    margin-bottom: var(--spacing-xs);
    margin-left: var(--spacing-sm);
}

/* ============================================
   响应式设计
============================================ */
@media (max-width: 768px) {
    .title-en {
        font-size: 2.5rem;
    }
    
    .title-zh {
        font-size: 1.5rem;
    }
    
    .detail-header {
        flex-direction: column;
        text-align: center;
    }
    
    .relic-image {
        width: 100%;
        height: 250px;
    }
    
    .relic-meta {
        flex-direction: column;
        gap: var(--spacing-xs);
    }
    
    .timeline-labels {
        flex-direction: column;
        gap: var(--spacing-sm);
    }
    
    .timeline-track {
        flex-wrap: wrap;
        gap: var(--spacing-sm);
    }
    
    .timeline-period {
        flex: 1 1 45%;
        min-width: 150px;
    }
    
    .period-avatar {
        width: 60px;
        height: 60px;
    }
    
    .period-label {
        font-size: 0.75rem;
    }
    
    .upload-options {
        flex-direction: column;
    }
    
    .upload-option-btn {
        max-width: 100%;
    }
    
    .modal-content {
        width: 95%;
        padding: var(--spacing-md);
    }
}

@media (max-width: 480px) {
    .title-en {
        font-size: 2rem;
    }
    
    .title-zh {
        font-size: 1.2rem;
    }
    
    .upload-btn {
        font-size: 1.1rem;
        padding: var(--spacing-sm) var(--spacing-lg);
    }
    
    .relic-title {
        font-size: 2rem;
    }
    
    .translation-text {
        font-size: 1.5rem;
    }
}

/* ============================================
   Loading Overlay & Analysis Progress
============================================ */
.loading-overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.85);
    z-index: 9999;
    justify-content: center;
    align-items: center;
}

.loading-content {
    background: white;
    padding: var(--spacing-xl);
    border-radius: 16px;
    text-align: center;
    max-width: 500px;
    box-shadow: var(--shadow-lg);
}

.loading-spinner {
    width: 60px;
    height: 60px;
    margin: 0 auto var(--spacing-md);
    border: 4px solid var(--soft-gray);
    border-top: 4px solid var(--primary-gold);
    border-radius: 50%;
    animation: spin 1s linear infinite;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.loading-content h3 {
    color: var(--ink-black);
    margin-bottom: var(--spacing-sm);
}

.loading-content p {
    color: #666;
    margin-bottom: var(--spacing-md);
}

.progress-container {
    width: 100%;
    height: 30px;
    background: var(--soft-gray);
    border-radius: 15px;
    overflow: hidden;
    margin-bottom: var(--spacing-sm);
}

.progress-bar {
    height: 100%;
    background: linear-gradient(90deg, var(--primary-gold), var(--dark-bronze));
    width: 0%;
    transition: width 0.3s ease;
    display: flex;
    align-items: center;
    justify-content: center;
    color: white;
    font-weight: 600;
}

.progress-text {
    font-size: 0.9rem;
    font-weight: 600;
    color: var(--primary-gold);
}

/* ============================================
   Travel Guide Card Styles
============================================ */
.travel-guide-card .guide-section {
    margin-bottom: var(--spacing-lg);
}

.travel-guide-card .guide-section:last-child {
    margin-bottom: 0;
}

.travel-guide-card h3 {
    font-size: 1.2rem;
    color: var(--dark-bronze);
    margin-bottom: var(--spacing-sm);
    padding-bottom: var(--spacing-xs);
    border-bottom: 2px solid var(--primary-gold);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.info-list,
.tips-list {
    list-style: none;
    padding: 0;
}

.info-list li {
    padding: var(--spacing-sm);
    margin-bottom: var(--spacing-xs);
    background: #F8F9FA;
    border-radius: 8px;
    border-left: 4px solid var(--primary-gold);
}

.tips-list li {
    padding: var(--spacing-sm) var(--spacing-sm) var(--spacing-sm) var(--spacing-lg);
    margin-bottom: var(--spacing-sm);
    background: linear-gradient(90deg, #FFF9E6, #FFF);
    border-radius: 8px;
    position: relative;
}

.tips-list li::before {
    content: '💡';
    position: absolute;
    left: var(--spacing-sm);
    font-size: 1.2rem;
}

/* ============================================
   Related Places Card Styles
============================================ */
.related-places-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: var(--spacing-md);
}

.related-place-item {
    background: linear-gradient(135deg, #F8F9FA, #FFF);
    padding: var(--spacing-md);
    border-radius: 12px;
    border: 2px solid var(--soft-gray);
    transition: all var(--transition-normal);
}

.related-place-item:hover {
    border-color: var(--primary-gold);
    transform: translateY(-4px);
    box-shadow: var(--shadow-md);
}

.related-place-item h4 {
    color: var(--dark-bronze);
    margin-bottom: var(--spacing-sm);
    display: flex;
    align-items: center;
    gap: var(--spacing-xs);
}

.place-distance {
    color: #666;
    font-size: 0.9rem;
    margin-bottom: var(--spacing-xs);
}

.place-reason {
    font-style: italic;
    color: #555;
    margin-bottom: var(--spacing-sm);
}

.place-highlights {
    list-style: none;
    padding: 0;
    margin-bottom: var(--spacing-md);
}

.place-highlights li {
    padding: var(--spacing-xs) 0;
    font-size: 0.95rem;
    color: #444;
}

.place-map-link {
    display: inline-flex;
    align-items: center;
    gap: var(--spacing-xs);
    color: var(--primary-gold);
    text-decoration: none;
    font-weight: 600;
    transition: all var(--transition-fast);
}

.place-map-link:hover {
    color: var(--dark-bronze);
    gap: var(--spacing-sm);
}

/* Responsive adjustments for new components */
@media (max-width: 768px) {
    .related-places-grid {
        grid-template-columns: 1fr;
    }
    
    .loading-content {
        width: 90%;
        padding: var(--spacing-md);
    }
}