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

/* Favorite Button Styles */
.favorite-container {
    margin: 5px 0;
    padding: 5px 0;
}

.favorite-btn {
    padding: 8px 15px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 0.9rem;
    transition: background-color 0.3s ease;
}

.favorite-btn:hover {
    background-color: #2980b9;
}

.favorite-btn.active {
    background-color: #e74c3c;
}

.favorite-btn.active:hover {
    background-color: #c0392b;
}

.favorite-btn:disabled,
.favorite-btn.disabled {
    background-color: #bdbdbd;
    cursor: not-allowed;
}

.favorite-btn:disabled:hover,
.favorite-btn.disabled:hover {
    background-color: #bdbdbd;
}

.unfavorite-btn {
    margin-left: 8px;
    padding: 0 10px;
    height: 1.8em;
    font-size: 1.8em;
    line-height: 1;
    display: inline-flex;
    align-items: center;
    border: 1px solid #e74c3c;
    background: transparent;
    color: #e74c3c;
    border-radius: 4px;
    cursor: pointer;
}

.unfavorite-btn:hover {
    background: #e74c3c;
    color: #fff;
}

.favorite-meta-row {
    display: flex;
    align-items: center;
    gap: 10px;
    flex-wrap: nowrap;
    margin-top: 0;
    font-size: 0.5em;
}

.favorite-source {
    white-space: nowrap;
    color: #666;
}

.favorite-pdf-link {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
    color: #3498db;
}

.history-item {
    padding: 0;
    border: none;
    border-radius: 0;
    background: transparent;
    margin-bottom: 8px;
}

.history-item:last-child {
    margin-bottom: 0;
}

.history-item-title {
    display: flex;
    align-items: baseline;
    gap: 10px;
    margin-bottom: 0;
}

.history-section .paper-title-link {
    text-decoration: none;
}

.commented-papers-container .paper-title-link {
    text-decoration: none;
}

.paper-title-link {
    flex: 1;
    min-width: 0;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.history-item-date {
    white-space: nowrap;
    font-size: 0.85rem;
    color: #999;
}

.login-tip {
    color: #666;
    font-size: 0.9rem;
    font-style: italic;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f7f9ff;
    background-image:
        radial-gradient(circle at top left, rgba(248, 251, 255, 1) 0, rgba(230, 240, 255, 1) 30%, rgba(246, 248, 255, 1) 60%, rgba(253, 253, 255, 1) 100%),
        url("data:image/svg+xml,%3Csvg xmlns='https://www.w3.org/2000/svg' width='1600' height='900' viewBox='0 0 1600 900'%3E%3Cdefs%3E%3CradialGradient id='g1' cx='30%25' cy='20%25' r='70%25'%3E%3Cstop offset='0' stop-color='%23ffffff' stop-opacity='0.95'/%3E%3Cstop offset='1' stop-color='%23ffffff' stop-opacity='0'/%3E%3C/radialGradient%3E%3CradialGradient id='g2' cx='75%25' cy='70%25' r='65%25'%3E%3Cstop offset='0' stop-color='%236aa9ff' stop-opacity='0.22'/%3E%3Cstop offset='1' stop-color='%236aa9ff' stop-opacity='0'/%3E%3C/radialGradient%3E%3ClinearGradient id='l1' x1='0' y1='0' x2='1' y2='1'%3E%3Cstop offset='0' stop-color='%23a6c8ff' stop-opacity='0.22'/%3E%3Cstop offset='1' stop-color='%23ffb6c1' stop-opacity='0.18'/%3E%3C/linearGradient%3E%3C/defs%3E%3Crect width='1600' height='900' fill='url(%23g1)'/%3E%3Crect width='1600' height='900' fill='url(%23g2)'/%3E%3Cpath d='M120 720 C 380 560, 540 820, 860 680 C 1080 580, 1240 520, 1480 590 L 1480 900 L 120 900 Z' fill='url(%23l1)'/%3E%3Ccircle cx='1220' cy='190' r='120' fill='%23bfe0ff' fill-opacity='0.25'/%3E%3Ccircle cx='1320' cy='260' r='70' fill='%23ffd3dc' fill-opacity='0.22'/%3E%3Ccircle cx='420' cy='210' r='90' fill='%2398c7ff' fill-opacity='0.18'/%3E%3C/svg%3E");
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    color: #333;
    line-height: 1.6;
    /* 确保body能够伸展到整个视口高度 */
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    /* 确保容器能够伸展，使页脚显示在底部 */
    flex: 1;
    /* 确保在小屏幕上占满整个屏幕宽度 */
    width: 100%;
}

/* Antigravity Theme Styles */
:root {
    --ag-bg: #ffffff;
    --ag-text-primary: #1a1a1a;
    --ag-text-secondary: #5f6368;
    --ag-accent: #4285f4; /* Google Blue */
    --ag-dark-card: #1e1e1e;
    --ag-font-sans: 'Google Sans', 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
}

body.antigravity-theme {
    font-family: var(--ag-font-sans);
    background-color: var(--ag-bg);
    color: var(--ag-text-primary);
    line-height: 1.5;
    background-image: none; /* Override global background */
    min-height: 100vh;
    display: block; /* Override flex */
}

/* Top Navigation */
.top-nav {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 80px;
    z-index: 1000;
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 0 48px;
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid rgba(0,0,0,0.05);
}

.nav-left {
    display: flex;
    align-items: center;
    gap: 60px;
}

.nav-logo {
    font-size: 24px;
    font-weight: 600;
    color: var(--ag-text-primary);
    text-decoration: none;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-links {
    display: flex;
    flex-direction: row;
    gap: 32px;
}

.nav-links a {
    color: var(--ag-text-secondary);
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: color 0.2s;
}

.nav-links a:hover {
    color: var(--ag-text-primary);
}

.download-pill-btn {
    display: flex;
    align-items: center;
    gap: 8px;
    background: #1a1a1a;
    color: #fff;
    padding: 10px 24px;
    border-radius: 999px;
    text-decoration: none;
    font-size: 14px;
    font-weight: 500;
    transition: all 0.2s ease;
}

.download-pill-btn:hover {
    transform: translateY(-1px);
    background: #000;
    box-shadow: 0 4px 12px rgba(0,0,0,0.1);
}

/* Hero Section */
.hero-section {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    text-align: center;
    padding: 0 20px;
    position: relative;
    overflow: hidden;
}

.hero-container {
    max-width: 900px;
    margin: 0 auto;
    animation: fadeUp 1s ease-out;
}

.hero-brand {
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 12px;
    font-size: 20px;
    font-weight: 500;
    margin-bottom: 40px;
    color: var(--ag-text-secondary);
}

.hero-title {
    font-size: 5rem;
    line-height: 1.1;
    font-weight: 600;
    margin-bottom: 24px;
    letter-spacing: -0.03em;
    color: #000;
}

.text-highlight {
    background: linear-gradient(90deg, #4285f4, #8ab4f8);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.5rem;
    color: var(--ag-text-secondary);
    margin-bottom: 48px;
    font-weight: 400;
    line-height: 1.6;
}

.hero-cta-group {
    display: flex;
    gap: 16px;
    justify-content: center;
}

.btn-primary-large {
    display: flex;
    align-items: center;
    gap: 10px;
    background: #1a1a1a;
    color: #fff;
    padding: 16px 32px;
    border-radius: 999px;
    text-decoration: none;
    font-size: 16px;
    font-weight: 500;
    transition: all 0.2s;
}

.btn-primary-large:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 20px rgba(0,0,0,0.1);
}

.btn-secondary-large {
    background: #f1f3f4;
    color: #1a1a1a;
    padding: 16px 32px;
    border-radius: 999px;
    border: none;
    font-size: 16px;
    font-weight: 500;
    cursor: pointer;
    transition: background-color 0.2s;
}

.btn-secondary-large:hover {
    background: #e8eaed;
}

/* Feature Sections */
.feature-section {
    padding: 160px 0;
    background: #fff;
    scroll-margin-top: 80px; /* Ensure anchor links land below the fixed nav */
}

.feature-container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 80px;
}

.feature-section.reverse .feature-container {
    flex-direction: row-reverse;
}

.feature-content {
    flex: 1;
    max-width: 480px;
}

.feature-title {
    font-size: 3rem;
    line-height: 1.2;
    margin-bottom: 24px;
    font-weight: 600;
    letter-spacing: -0.02em;
}

.feature-desc {
    font-size: 1.25rem;
    color: var(--ag-text-secondary);
    line-height: 1.6;
    margin-bottom: 32px;
}

.feature-tags {
    display: flex;
    gap: 12px;
    flex-wrap: wrap;
}

.feature-tags span {
    background: #f1f3f4;
    padding: 6px 12px;
    border-radius: 8px;
    font-size: 0.9rem;
    color: #5f6368;
    font-weight: 500;
}

/* Visual Cards */
.feature-visual {
    flex: 1;
    display: flex;
    justify-content: center;
}

.visual-card {
    width: 100%;
    max-width: 540px;
    aspect-ratio: 4/3;
    background: var(--ag-dark-card);
    border-radius: 24px;
    box-shadow: 0 30px 60px rgba(0,0,0,0.15);
    overflow: hidden;
    position: relative;
    padding: 32px;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease;
}

.visual-card:hover {
    transform: translateY(-10px) scale(1.02);
}

/* Card: Analysis UI */
.card-analysis {
    background: #1e1e1e;
    border: 1px solid #333;
}

.card-header {
    display: flex;
    gap: 8px;
    margin-bottom: 24px;
}

.dot { width: 12px; height: 12px; border-radius: 50%; }
.red { background: #ff5f56; }
.yellow { background: #ffbd2e; }
.green { background: #27c93f; }

.skeleton-line {
    height: 12px;
    background: #333;
    border-radius: 6px;
    margin-bottom: 12px;
}

.skeleton-line.w-75 { width: 75%; }
.skeleton-line.w-50 { width: 50%; }
.skeleton-line.w-90 { width: 90%; }
.skeleton-line.w-60 { width: 60%; }

.skeleton-block {
    margin: 24px 0;
}

.analysis-highlight {
    background: rgba(66, 133, 244, 0.1);
    border-left: 3px solid #4285f4;
    padding: 16px;
    border-radius: 0 8px 8px 0;
    color: #d0d0d0;
}

.highlight-icon { margin-bottom: 8px; }
.highlight-text { font-family: monospace; font-size: 14px; line-height: 1.4; }

/* Card: Discuss UI */
.card-discuss {
    background: #f8f9fa;
    border: 1px solid #e0e0e0;
}

.chat-bubble {
    display: flex;
    gap: 12px;
    margin-bottom: 20px;
    animation: fadeUp 0.5s ease forwards;
    opacity: 0;
}

.chat-bubble:nth-child(1) { animation-delay: 0.2s; }
.chat-bubble:nth-child(2) { animation-delay: 0.8s; }
.chat-bubble:nth-child(3) { animation-delay: 1.4s; }

.chat-bubble.right { flex-direction: row-reverse; }

.avatar {
    width: 36px; height: 36px;
    border-radius: 50%;
    background: #ddd;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 14px;
    color: #555;
}

.chat-bubble.right .avatar { background: #4285f4; color: #fff; }

.bubble-content {
    background: #fff;
    padding: 12px 16px;
    border-radius: 12px;
    font-size: 14px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.05);
    max-width: 80%;
    color: #333;
}

.chat-bubble.right .bubble-content {
    background: #4285f4;
    color: #fff;
}

/* Card: Resource UI */
.card-resource {
    background: #fff;
    border: 1px solid #eee;
    padding: 0;
}

.resource-item {
    display: flex;
    align-items: center;
    padding: 20px 24px;
    border-bottom: 1px solid #f0f0f0;
}

.file-icon {
    width: 40px; height: 40px;
    background: #ffebee;
    color: #d32f2f;
    border-radius: 8px;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 700;
    font-size: 12px;
    margin-right: 16px;
}

.file-info { flex: 1; }
.file-name { font-size: 14px; font-weight: 500; margin-bottom: 4px; color: #1a1a1a; }
.file-meta { font-size: 12px; color: #888; }

.download-icon {
    width: 32px; height: 32px;
    border-radius: 50%;
    background: #f5f5f5;
    display: flex;
    align-items: center;
    justify-content: center;
    color: #333;
    cursor: pointer;
}

.upload-status {
    padding: 24px;
    background: #fafafa;
    margin-top: auto;
}

.progress-bar {
    height: 4px;
    background: #e0e0e0;
    border-radius: 2px;
    margin-bottom: 8px;
    overflow: hidden;
}

.progress-fill {
    height: 100%;
    width: 60%;
    background: #4285f4;
    border-radius: 2px;
    animation: progress 2s infinite ease-in-out;
}

.status-text { font-size: 12px; color: #666; text-align: right; }

/* Footer */
.simple-footer {
    padding: 60px 0;
    border-top: 1px solid #eee;
    background: #fff;
}

.footer-content {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 48px;
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.footer-logo { font-weight: 600; font-size: 18px; }
.footer-links { display: flex; gap: 24px; }
.footer-links a { color: #5f6368; text-decoration: none; font-size: 14px; }
.footer-copyright { font-size: 12px; color: #999; }

/* Animations */
@keyframes fadeUp {
    from { opacity: 0; transform: translateY(20px); }
    to { opacity: 1; transform: translateY(0); }
}

@keyframes progress {
    0% { width: 0; }
    50% { width: 80%; }
    100% { width: 100%; }
}

/* Responsive */
@media (max-width: 768px) {
    .top-nav {
        padding: 0 20px;
        height: 70px;
    }
    
    .nav-left {
        gap: 20px;
    }
    
    .nav-links {
        display: none; /* Hide links on mobile for simplicity, or use a hamburger menu */
    }
    
    .hero-title { font-size: 3rem; }
    .feature-container { flex-direction: column !important; padding: 0 24px; gap: 40px; }
    .feature-content { text-align: center; max-width: 100%; }
    .feature-tags { justify-content: center; }
    .visual-card { max-width: 100%; }
}

/* 主标题 */
.main-title {
    text-align: center;
    margin: 12px 0;
}

.main-title h2 {
    font-size: 1.8rem;
    color: #333;
    font-weight: normal;
}

/* 搜索区域 */
.search-section {
    padding: 20px 0;
    margin-bottom: 0;
}

.search-main {
    display: flex;
    gap: 10px;
    margin-bottom: 15px;
    align-items: center;
}

.search-input {
    width: 100%;
    flex: 1;
    padding: 10px 15px;
    font-size: 1rem;
    height: 40px;
    border: 1px solid #ddd;
    border-radius: 4px;
    outline: none;
    box-sizing: border-box;
}

.search-input:focus {
    border-color: #3498db;
}

/* 搜索历史样式 */
.search-input-wrapper {
    position: relative;
    flex: 1;
}

.search-history-container {
    position: absolute;
    bottom: 100%;
    left: 0;
    right: 0;
    background-color: white;
    border: 1px solid #ddd;
    border-bottom: none;
    border-radius: 4px 4px 0 0;
    box-shadow: 0 -2px 8px rgba(0, 0, 0, 0.1);
    z-index: 100;
    display: none;
    margin-bottom: -1px;
}

.search-history-container.show {
    display: block;
}

.search-history-header {
    position: relative;
}

.search-history-list {
    max-height: 200px;
    overflow-y: auto;
}

.close-history-btn {
    position: absolute;
    top: 5px;
    right: 5px;
    background: none;
    border: none;
    font-size: 16px;
    cursor: pointer;
    color: #666;
    padding: 2px 5px;
    border-radius: 3px;
    transition: background-color 0.2s ease, color 0.2s ease;
}

.close-history-btn:hover {
    background-color: #f0f0f0;
    color: #333;
}

.search-history-item {
    padding: 3px 5px !important;
    cursor: pointer;
    transition: background-color 0.2s ease;
}

.search-history-item:hover {
    background-color: #f8f9fa;
}

.search-history-item:last-child {
    border-bottom: none;
}

/* 历史记录页面样式 */
.history-actions {
    display: flex;
    gap: 10px;
    align-items: center;
    margin-bottom: 12px;
}

.history-actions .search-input-wrapper {
    display: flex;
    align-items: center;
    flex: 1;
    width: 100%;
}

.history-actions .search-input {
    flex: 1;
    margin-right: 5px;
    border-radius: 4px;
    border-right: 1px solid #ddd;
}

.history-actions .search-btn {
    border-radius: 4px;
    margin-left: 5px;
    border-left: 1px solid #ddd;
    padding-left: 15px;
    padding-right: 15px;
}

.history-actions .search-btn.red {
    border-radius: 4px;
}

.search-btn {
    padding: 0 20px;
    font-size: 1rem;
    height: 40px;
    background-color: #f8f9fa;
    color: #333;
    border: 1px solid #ddd;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease;
    box-sizing: border-box;
    display: flex;
    align-items: center;
    justify-content: center;
}

.search-btn.blue {
    background-color: #3498db;
    color: white;
    border-color: #3498db;
}

.search-btn:hover {
    background-color: #e9ecef;
}

.search-btn.blue:hover {
    background-color: #2980b9;
}

/* 搜索状态 */
.search-status {
    margin-top: 10px;
    font-size: 0.9rem;
    color: #666;
    text-align: left;
}

/* 筛选条件 */
.search-filters {
    display: flex;
    gap: 10px;
    align-items: center;
    flex-wrap: wrap;
}

.filter-select {
    padding: 10px 15px;
    font-size: 1rem;
    height: 40px;
    border: 1px solid #ddd;
    border-radius: 4px;
    outline: none;
    min-width: 120px;
    box-sizing: border-box;
}

.filter-input {
    padding: 8px 12px;
    font-size: 0.9rem;
    border: 1px solid #ddd;
    border-radius: 4px;
    outline: none;
    width: 180px;
}

.filter-btn {
    padding: 8px 15px;
    font-size: 0.9rem;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

.filter-btn.green {
    background-color: #27ae60;
    color: white;
}

.filter-btn.green:hover {
    background-color: #229954;
}

/* 搜索结果 */
.results-section {
    padding: 20px 0;
}

.results-count {
    font-size: 1rem;
    margin-bottom: 15px;
    color: #666;
}

.papers-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(350px, 1fr));
    gap: 15px;
}

/* 论文卡片 */
.paper-card {
    padding: 15px;
    cursor: pointer;
    transition: all 0.3s ease;
    border-bottom: 1px solid #e1e8ed;
}

.paper-card:hover {
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    transform: translateY(-2px);
}

.paper-card h3 {
    font-size: 0.9rem;
    margin-bottom: 10px;
    color: #333;
    line-height: 1.4;
}

.paper-card .paper-card-meta {
    font-size: 0.6rem;
    color: #666;
    margin-bottom: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.paper-card .paper-card-categories {
    font-size: 0.8rem;
    color: #666;
    margin-bottom: 10px;
}

/* 论文详情页 */
.paper-detail {
    padding: 20px 0;
}

.paper-header {
    margin-bottom: 20px;
}

.paper-title {
    font-size: 1.5rem;
    margin-bottom: 4px;
    color: #333;
    line-height: 1.4;
}

/* Commented papers title */
.commented-paper-title {
    font-size: 1rem;
    font-weight: normal;
    margin-bottom: 2px;
}

.paper-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 15px;
    align-items: center;
    margin-bottom: 15px;
    color: #666;
}

.paper-date {
    font-size: 0.9rem;
    margin-top: 0;
}

.commented-papers-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.commented-paper-item {
    padding: 0;
    border: none;
    border-radius: 0;
    background: transparent;
}

.commented-paper-item .history-item-date {
    font-size: 0.9rem;
}

.paper-categories {
    font-size: 0.9rem;
    color: #333;
}

.paper-info-row {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
    align-items: center;
    margin-bottom: 10px;
}

.url-paper-meta-row {
    display: flex;
    align-items: center;
    gap: 12px;
    flex-wrap: nowrap;
    margin-bottom: 10px;
}

.url-paper-meta-row .paper-source {
    white-space: nowrap;
}

/* Modal Styles */
.modal-overlay {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.5);
    backdrop-filter: blur(4px);
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    visibility: hidden;
    transition: all 0.3s ease;
}

.modal-overlay.show {
    opacity: 1;
    visibility: visible;
}

.modal-content {
    background: #fff;
    width: 90%;
    max-width: 500px;
    border-radius: 24px;
    padding: 32px;
    position: relative;
    box-shadow: 0 20px 40px rgba(0,0,0,0.2);
    transform: translateY(20px);
    transition: transform 0.3s cubic-bezier(0.16, 1, 0.3, 1);
    max-height: 90vh;
    overflow-y: auto;
}

.modal-overlay.show .modal-content {
    transform: translateY(0);
}

.modal-close {
    position: absolute;
    top: 20px;
    right: 20px;
    background: transparent;
    border: none;
    color: #999;
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: background 0.2s;
    display: flex;
    align-items: center;
    justify-content: center;
}

.modal-close:hover {
    background: #f1f3f4;
    color: #333;
}

.modal-header-center {
    text-align: center;
    margin-bottom: 24px;
}

.modal-icon {
    width: 64px;
    height: 64px;
    background: #e8f0fe;
    color: #1967d2;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin: 0 auto 16px;
}

.modal-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #1a1a1a;
    margin: 0;
}

.download-section {
    text-align: center;
    margin-bottom: 32px;
}

.download-tip {
    font-size: 0.9rem;
    color: #666;
    margin-bottom: 16px;
}

.btn-baidu-download {
    display: flex;
    align-items: center;
    justify-content: center;
    background: #06a7ff; /* Baidu Netdisk Blueish */
    color: white;
    padding: 14px 32px;
    border-radius: 999px;
    text-decoration: none;
    font-weight: 500;
    font-size: 1.1rem;
    margin-bottom: 16px;
    transition: background 0.2s;
    box-shadow: 0 4px 12px rgba(6, 167, 255, 0.3);
}

.btn-baidu-download:hover {
    background: #0095ef;
    transform: translateY(-1px);
}

.modal-divider {
    display: flex;
    align-items: center;
    margin: 24px 0;
    color: #999;
    font-size: 0.9rem;
}

.modal-divider::before,
.modal-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: #eee;
}

.modal-divider span {
    padding: 0 16px;
}

.tutorial-list {
    display: flex;
    flex-direction: column;
    gap: 16px;
}

.tutorial-item {
    display: flex;
    gap: 16px;
    align-items: flex-start;
}

.step-num {
    width: 28px;
    height: 28px;
    background: #f1f3f4;
    color: #5f6368;
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: 600;
    font-size: 0.9rem;
    flex-shrink: 0;
    margin-top: 2px;
}

.step-content h4 {
    font-size: 1rem;
    font-weight: 600;
    margin-bottom: 4px;
    color: #333;
}

.step-content p {
    font-size: 0.9rem;
    color: #666;
    line-height: 1.5;
    margin: 0;
}

.code-snippet {
    background: #f1f3f4;
    padding: 2px 6px;
    border-radius: 4px;
    font-family: monospace;
    font-size: 0.85em;
    color: #d93025;
}

/* Auth Page Layout */
body.auth-page {
    font-family: 'Inter', 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background: radial-gradient(circle at top, #f1f5ff 0%, #e5edff 45%, #eef2ff 70%, #fef9ff 100%);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: #1f2946;
    padding-bottom: clamp(24px, 4vh, 48px);
}

.auth-page .navbar {
    background: transparent;
    padding: 18px 0 6px;
}

.auth-page .navbar .logo {
    font-size: 1.4rem;
    font-weight: 600;
    color: #101a34;
    text-decoration: none;
}

.auth-page-container {
    width: 100%;
    flex: 1;
    display: flex;
    align-items: stretch;
    justify-content: center;
    padding: clamp(12px, 4vh, 32px) 20px clamp(16px, 5vh, 40px);
    min-height: calc(100vh - 140px);
}

.auth-section {
    width: 100%;
    max-width: min(1180px, 100%);
    margin: 0 auto;
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: clamp(24px, 4vw, 48px);
    background: rgba(255, 255, 255, 0.78);
    border-radius: 28px;
    padding: clamp(24px, 4vw, 40px);
    box-shadow: 0 20px 60px rgba(15, 23, 42, 0.16);
    backdrop-filter: blur(14px);
    align-items: stretch;
    min-height: clamp(500px, 70vh, 640px);
}

.auth-section.single-column {
    max-width: 520px;
    grid-template-columns: 1fr;
    padding: clamp(24px, 5vw, 36px);
    min-height: auto;
}

.auth-card {
    background: rgba(255, 255, 255, 0.92);
    border-radius: 24px;
    padding: clamp(28px, 4vw, 40px);
    box-shadow: inset 0 1px 0 rgba(255, 255, 255, 0.6);
    border: 1px solid rgba(226, 232, 240, 0.7);
    display: flex;
    flex-direction: column;
    justify-content: center;
    gap: 24px;
}

.auth-card-header {
    margin-bottom: 8px;
}

.auth-pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    padding: 6px 14px;
    border-radius: 999px;
    background: rgba(82, 106, 255, 0.1);
    color: #4b6bff;
    font-size: 0.85rem;
    font-weight: 600;
}

.auth-title {
    font-size: 2rem;
    margin: 16px 0 8px;
    color: #0f172a;
}

.auth-subtitle {
    color: #5b647d;
    font-size: 1rem;
}

.auth-form .form-group {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-bottom: 18px;
}

.auth-form .form-label {
    font-size: 0.95rem;
    color: #4b5164;
    font-weight: 500;
}

.auth-input {
    width: 100%;
    padding: 14px 16px;
    border-radius: 14px;
    border: 1px solid #d6dbf2;
    background: #f9faff;
    font-size: 1rem;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.auth-input:focus {
    outline: none;
    border-color: #5a6efb;
    box-shadow: 0 0 0 3px rgba(90, 110, 251, 0.15);
    background: #fff;
}

.form-meta {
    display: flex;
    align-items: center;
    justify-content: space-between;
    margin-bottom: 24px;
    font-size: 0.9rem;
}

.form-tip {
    font-size: 0.85rem;
    color: #7b84a9;
    margin-bottom: 18px;
}

.remember-option {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    color: #4f5a77;
}

.remember-option input {
    width: 16px;
    height: 16px;
    accent-color: #5a6efb;
}

.text-link {
    color: #4655ff;
    text-decoration: none;
    font-weight: 600;
}

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

.primary-btn {
    border: none;
    border-radius: 16px;
    padding: 14px 24px;
    background: linear-gradient(135deg, #5f78ff, #7d9bff);
    color: #fff;
    font-size: 1rem;
    font-weight: 600;
    cursor: pointer;
    box-shadow: 0 12px 25px rgba(95, 120, 255, 0.35);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.primary-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 18px 25px rgba(95, 120, 255, 0.45);
}

.full-width {
    width: 100%;
}

.auth-divider {
    display: flex;
    align-items: center;
    gap: 12px;
    margin: 15px 0 12px;
    color: #9aa3c1;
    font-size: 0.9rem;
}

.auth-divider::before,
.auth-divider::after {
    content: "";
    flex: 1;
    height: 1px;
    background: linear-gradient(90deg, rgba(154, 163, 193, 0), rgba(154, 163, 193, 0.6), rgba(154, 163, 193, 0));
}

.secondary-actions {
    display: flex;
    justify-content: center;
}

.secondary-actions a {
    font-size: 0.95rem;
}

.auth-page .footer {
    background: transparent;
    text-align: center;
    padding: 8px 0;
    margin-top: clamp(12px, 3vh, 28px);
    color: #6c7490;
}

@media (max-width: 960px) {
    .auth-page-container {
        min-height: auto;
        padding: 24px 16px 32px;
    }

    .auth-section {
        grid-template-columns: 1fr;
        padding: clamp(20px, 5vw, 32px);
    }

    .auth-card,
    .auth-showcase {
        padding: clamp(20px, 5vw, 32px);
    }
}

@media (max-width: 640px) {
    .auth-page-container {
        padding: 16px 12px 28px;
    }

    .auth-section {
        padding: 20px;
        gap: 20px;
    }

    .form-meta {
        flex-direction: column;
        gap: 16px;
        align-items: flex-start;
    }
}

@media (max-height: 780px) and (min-width: 768px) {
    .auth-page-container {
        min-height: auto;
        padding: 16px 20px 24px;
    }

    .auth-section {
        min-height: auto;
    }
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    background-color: #f5f7fa;
    color: #333;
    line-height: 1.6;
}

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

header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 20px 0;
    margin-bottom: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.header-content {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0 20px;
}

.header-content h1 {
    font-size: 24px;
    font-weight: 600;
}

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

.logout-btn {
    background: rgba(255, 255, 255, 0.2);
    border: none;
    color: white;
    padding: 8px 16px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 14px;
    transition: background 0.3s;
}

.logout-btn:hover {
    background: rgba(255, 255, 255, 0.3);
}

.stats-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 20px;
    margin-bottom: 30px;
}

.stat-card {
    background: white;
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    transition: transform 0.3s, box-shadow 0.3s;
}

.stat-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
}

.stat-card h3 {
    font-size: 14px;
    color: #666;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 0.5px;
}

.stat-card .value {
    font-size: 28px;
    font-weight: 700;
    color: #667eea;
}

.section {
    background: white;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.05);
    margin-bottom: 30px;
    overflow: hidden;
}

.section-header {
    padding: 20px;
    border-bottom: 1px solid #f0f0f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.section-header h2 {
    font-size: 18px;
    font-weight: 600;
    color: #333;
}

.section-content {
    padding: 20px;
}

.search-container {
    margin-bottom: 20px;
    display: flex;
    gap: 10px;
}

.search-input {
    flex: 1;
    padding: 10px 15px;
    border: 1px solid #ddd;
    border-radius: 20px;
    font-size: 14px;
    transition: border-color 0.3s;
}

.search-input:focus {
    outline: none;
    border-color: #667eea;
}

.sort-buttons {
    display: flex;
    gap: 10px;
}

.btn {
    padding: 8px 16px;
    border: 1px solid #ddd;
    border-radius: 20px;
    background: white;
    cursor: pointer;
    font-size: 14px;
    transition: all 0.3s;
}

.btn:hover {
    border-color: #667eea;
    color: #667eea;
}

.btn.active {
    background: #667eea;
    color: white;
    border-color: #667eea;
}

table {
    width: 100%;
    border-collapse: collapse;
    font-size: 14px;
}

th, td {
    padding: 12px 15px;
    text-align: left;
    border-bottom: 1px solid #f0f0f0;
}

th {
    background-color: #f8f9fa;
    font-weight: 600;
    color: #333;
}

tr:hover {
    background-color: #f8f9fa;
}

.limit-input {
    width: 80px;
    padding: 5px 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    font-size: 14px;
}

.save-btn {
    background: #48bb78;
    color: white;
    border: none;
    padding: 5px 12px;
    border-radius: 4px;
    cursor: pointer;
    font-size: 12px;
    transition: background 0.3s;
}

.save-btn:hover {
    background: #38a169;
}

.papers-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 15px;
}

.paper-card {
    border: 1px solid #f0f0f0;
    border-radius: 8px;
    padding: 15px;
    transition: transform 0.3s, box-shadow 0.3s;
}

.paper-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.05);
}

.paper-card h4 {
    font-size: 14px;
    font-weight: 600;
    margin-bottom: 8px;
    color: #333;
    line-height: 1.4;
}

.paper-card .hit-count {
    font-size: 12px;
    color: #667eea;
    font-weight: 600;
}

.table-container {
    overflow-x: auto;
}

.loading {
    display: flex;
    justify-content: center;
    align-items: center;
    padding: 40px;
    color: #666;
}

.error {
    padding: 15px;
    background: #fed7d7;
    color: #c53030;
    border-radius: 6px;
    margin-bottom: 20px;
    font-size: 14px;
}

.success {
    padding: 15px;
    background: #c6f6d5;
    color: #276749;
    border-radius: 6px;
    margin-bottom: 20px;
    font-size: 14px;
}

@media (max-width: 768px) {
    .stats-grid {
        grid-template-columns: 1fr;
    }

    .section-header {
        flex-direction: column;
        align-items: flex-start;
        gap: 10px;
    }

    .sort-buttons {
        flex-wrap: wrap;
    }

    .search-container {
        flex-direction: column;
    }
}

.modal {
    display: none;
    position: fixed;
    z-index: 1000;
    left: 0;
    top: 0;
    width: 100%;
    height: 100%;
    overflow: auto;
    background-color: rgba(0,0,0,0.5);
}

.modal-content {
    background-color: #fefefe;
    margin: 15% auto;
    padding: 20px;
    border: 1px solid #888;
    width: 400px;
    max-width: 90%;
    border-radius: 10px;
    box-shadow: 0 4px 20px rgba(0,0,0,0.15);
    animation: modalFadeIn 0.3s ease-out;
}

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

.modal-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding-bottom: 10px;
    border-bottom: 1px solid #e9ecef;
}

.modal-header h3 {
    margin: 0;
    color: #333;
    font-size: 18px;
}

.close-btn {
    background: none;
    border: none;
    font-size: 24px;
    cursor: pointer;
    color: #666;
}

.close-btn:hover {
    color: #333;
}

.form-group {
    margin-bottom: 20px;
}

.form-group label {
    display: block;
    margin-bottom: 8px;
    font-weight: 500;
    color: #555;
}

.form-group input {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 14px;
}

.form-group input:focus {
    outline: none;
    border-color: #667eea;
    box-shadow: 0 0 0 2px rgba(102, 126, 234, 0.2);
}

.modal-footer {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 20px;
    padding-top: 10px;
    border-top: 1px solid #e9ecef;
}

.cancel-btn {
    background-color: #f8f9fa;
    color: #333;
    border: 1px solid #ddd;
    padding: 8px 16px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}

.cancel-btn:hover {
    background-color: #e9ecef;
}

.confirm-btn {
    background-color: #667eea;
    color: white;
    border: none;
    padding: 8px 16px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 14px;
    transition: background-color 0.3s;
}

.confirm-btn:hover {
    background-color: #5a6fd8;
}