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

:root {
    --bg-primary: #1a1a2e;
    --bg-secondary: #16213e;
    --bg-card: #0f3460;
    --text-primary: #eaeaea;
    --text-secondary: #a0a0a0;
    --accent: #e94560;
    --accent-hover: #ff6b6b;
    --border: #2a2a4a;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.4);
    --gradient: linear-gradient(135deg, var(--accent), var(--accent-hover));
}

.light-theme {
    --bg-primary: #f5f5f5;
    --bg-secondary: #ffffff;
    --bg-card: #ffffff;
    --text-primary: #333333;
    --text-secondary: #666666;
    --accent: #e94560;
    --accent-hover: #ff6b6b;
    --border: #e0e0e0;
    --shadow: 0 4px 20px rgba(0, 0, 0, 0.08);
    --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.12);
    --gradient: linear-gradient(135deg, var(--accent), var(--accent-hover));
}

body {
    font-family: 'Noto Serif SC', serif;
    background-color: var(--bg-primary);
    color: var(--text-primary);
    line-height: 1.8;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

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

/* Header */
.header {
    background-color: var(--bg-secondary);
    border-bottom: 1px solid var(--border);
    padding: 20px 0;
    position: sticky;
    top: 0;
    z-index: 100;
    box-shadow: var(--shadow);
}

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

.logo {
    font-size: 24px;
    font-weight: 700;
    cursor: pointer;
    color: var(--accent);
    transition: color 0.3s;
}

.logo:hover {
    color: var(--accent-hover);
}

.theme-btn {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    padding: 8px 12px;
    border-radius: 50%;
    transition: background-color 0.3s;
}

.theme-btn:hover {
    background-color: var(--bg-card);
}

/* Main */
.main {
    flex: 1;
    padding: 40px 0;
}

/* Home Page - Novel List */
.novel-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 30px;
}

.novel-card {
    background-color: var(--bg-card);
    border-radius: 16px;
    padding: 30px;
    cursor: pointer;
    transition: transform 0.3s ease, box-shadow 0.3s ease, border-color 0.3s ease;
    border: 1px solid var(--border);
    position: relative;
    overflow: hidden;
}

.novel-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 3px;
    background: var(--gradient);
    transform: scaleX(0);
    transition: transform 0.3s ease;
}

.novel-card:hover::before {
    transform: scaleX(1);
}

.novel-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--shadow-lg);
    border-color: var(--accent);
}

.novel-card h2 {
    font-size: 22px;
    margin-bottom: 15px;
    color: var(--accent);
}

.novel-card .meta {
    color: var(--text-secondary);
    font-size: 14px;
    margin-bottom: 10px;
}

.novel-card .desc {
    color: var(--text-secondary);
    font-size: 15px;
    line-height: 1.7;
}

.novel-card .progress {
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px solid var(--border);
    font-size: 14px;
    color: var(--text-secondary);
}

/* Novel Detail */
.novel-detail .novel-header {
    background-color: var(--bg-card);
    border-radius: 12px;
    padding: 40px;
    margin-bottom: 30px;
    border: 1px solid var(--border);
}

.novel-detail h1 {
    font-size: 36px;
    margin-bottom: 20px;
    color: var(--accent);
}

.novel-detail .novel-meta {
    display: flex;
    gap: 30px;
    margin-bottom: 25px;
    color: var(--text-secondary);
    flex-wrap: wrap;
}

.novel-detail .novel-desc {
    font-size: 17px;
    line-height: 1.9;
    color: var(--text-primary);
}

.chapter-list {
    background-color: var(--bg-card);
    border-radius: 12px;
    padding: 30px;
    border: 1px solid var(--border);
}

.chapter-list h3 {
    font-size: 20px;
    margin-bottom: 25px;
    padding-bottom: 15px;
    border-bottom: 1px solid var(--border);
}

.chapter-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 15px;
}

.chapter-item {
    padding: 15px 20px;
    background-color: var(--bg-secondary);
    border-radius: 8px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s;
    border: 1px solid var(--border);
}

.chapter-item:hover {
    background-color: var(--accent);
    transform: translateX(5px);
}

/* Reader */
.reader {
    max-width: 800px;
    margin: 0 auto;
    animation: fadeIn 0.3s ease-out;
}

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

/* Page transition */
#content {
    animation: slideIn 0.3s ease-out;
}

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

.reader-header {
    display: grid;
    grid-template-columns: auto 1fr auto;
    align-items: center;
    gap: 15px;
    margin-bottom: 30px;
    padding: 16px 20px;
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: var(--shadow);
    position: relative;
    z-index: 100;
}

.reader-header .back-btn {
    background: none;
    border: none;
    color: var(--accent);
    font-size: 16px;
    cursor: pointer;
    padding: 10px 15px;
    border-radius: 6px;
    transition: background-color 0.3s;
}

.reader-header .back-btn:hover {
    background-color: var(--bg-card);
}

.reader-header .chapter-nav {
    display: flex;
    gap: 10px;
}

.reader-header .nav-btn {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 10px 20px;
    border-radius: 6px;
    cursor: pointer;
    transition: background-color 0.3s;
}

.reader-header .nav-btn:hover:not(:disabled) {
    background-color: var(--accent);
    border-color: var(--accent);
}

.reader-header .nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.reader-content {
    font-size: 18px;
    line-height: 2;
    color: var(--text-primary);
}

.reader-content h1,
.reader-content h2,
.reader-content h3 {
    margin: 40px 0 20px;
    color: var(--accent);
}

.reader-content p {
    margin-bottom: 25px;
    text-indent: 2em;
}

.reader-content strong {
    color: var(--accent);
}

.reader-content em {
    font-style: italic;
}

.reader-footer {
    margin-top: 60px;
    padding: 30px 20px;
    border-top: 1px solid var(--border);
    display: flex;
    justify-content: center;
    gap: 20px;
    background-color: var(--bg-card);
    border-radius: 12px;
    box-shadow: var(--shadow);
    position: relative;
    z-index: 100;
}

.reader-footer .nav-btn {
    min-width: 140px;
    padding: 14px 24px;
    font-size: 16px;
}

/* Loading */
.loading {
    text-align: center;
    padding: 60px;
    font-size: 18px;
    color: var(--text-secondary);
}

/* Footer */
.footer {
    background-color: var(--bg-secondary);
    border-top: 1px solid var(--border);
    padding: 30px 0;
    text-align: center;
    color: var(--text-secondary);
    font-size: 14px;
    margin-top: auto;
}

/* Responsive */
@media (max-width: 768px) {
    .container {
        padding: 0 15px;
    }

    .header {
        padding: 15px 0;
    }

    .logo {
        font-size: 20px;
    }

    .main {
        padding: 25px 0;
    }

    .novel-list {
        grid-template-columns: 1fr;
        gap: 20px;
    }

    .novel-card {
        padding: 25px;
    }

    .novel-detail .novel-header {
        padding: 25px;
    }

    .novel-detail h1 {
        font-size: 28px;
    }

    .chapter-grid {
        grid-template-columns: 1fr;
    }

    .reader-content {
        font-size: 17px;
        line-height: 1.9;
    }

    .reader-content p {
        margin-bottom: 20px;
    }
}



/* Font size controls */
.font-controls {
    display: flex;
    gap: 10px;
    align-items: center;
    background-color: var(--bg-secondary);
    padding: 6px 10px;
    border-radius: 8px;
    border: 1px solid var(--border);
}

.font-controls::before {
    content: 'Aa';
    font-size: 14px;
    color: var(--text-secondary);
    margin-right: 5px;
}

.font-btn {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-primary);
    width: 36px;
    height: 36px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 18px;
    font-weight: 600;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: all 0.2s ease;
}

.font-btn:hover {
    background-color: var(--accent);
    border-color: var(--accent);
    color: white;
    transform: scale(1.1);
}

/* Page title */
.page-title {
    font-size: 28px;
    margin-bottom: 30px;
    color: var(--text-primary);
}

/* Download button & Continue button */
.download-btn,
.continue-btn {
    background: var(--gradient);
    border: none;
    color: white;
    font-weight: 600;
    letter-spacing: 0.5px;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
    padding: 12px 24px;
    border-radius: 8px;
    cursor: pointer;
    font-size: 16px;
    margin-top: 15px;
}

.continue-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 15px rgba(233, 69, 96, 0.4);
}

.continue-btn:active {
    transform: translateY(0);
}

/* Button base style upgrade */
.nav-btn {
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    color: var(--text-primary);
    padding: 10px 20px;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    font-weight: 500;
}

.nav-btn:hover:not(:disabled) {
    background-color: var(--accent);
    border-color: var(--accent);
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(233, 69, 96, 0.3);
}

.nav-btn:disabled {
    opacity: 0.5;
    cursor: not-allowed;
}

.nav-btn:active:not(:disabled) {
    transform: translateY(0);
}

/* Back button */
.back-btn {
    background: none;
    border: 1px solid var(--border);
    color: var(--accent);
    font-size: 15px;
    cursor: pointer;
    padding: 10px 16px;
    border-radius: 8px;
    transition: all 0.2s ease;
    font-weight: 500;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    white-space: nowrap;
}

.back-btn:hover {
    background-color: var(--bg-secondary);
    border-color: var(--accent);
    transform: translateX(-2px);
}

/* Reading progress bar */
.progress-bar {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    background: linear-gradient(90deg, var(--accent), var(--accent-hover));
    z-index: 1000;
    transition: width 0.1s;
}

/* Smooth scroll */
html {
    scroll-behavior: smooth;
}

/* Selection */
::selection {
    background-color: var(--accent);
    color: white;
}

/* Reader content enhancement */
.reader-content {
    text-align: justify;
    hyphens: auto;
}

.reader-content p {
    transition: background-color 0.2s;
    padding: 2px 4px;
    border-radius: 4px;
}

.reader-content p:hover {
    background-color: var(--bg-card);
}

/* Improved buttons */
.nav-btn,
.font-btn,
.back-btn,
.theme-btn {
    position: relative;
    overflow: hidden;
}

.nav-btn:active:not(:disabled),
.font-btn:active,
.back-btn:active,
.theme-btn:active {
    transform: scale(0.95);
}

/* Chapter read indicator */
.chapter-item.read {
    opacity: 0.7;
    border-left: 3px solid var(--accent);
}

.chapter-item.current {
    background-color: var(--accent) !important;
    border-color: var(--accent);
}

/* Reader header button layout */
.reader-header .chapter-nav {
    display: flex;
    gap: 10px;
}

/* Mobile reader optimization */
@media (max-width: 768px) {
    .reader-header {
        grid-template-columns: 1fr 1fr;
        gap: 12px;
        padding: 16px;
    }
    
    .reader-header .back-btn {
        grid-column: 1 / -1;
        grid-row: 1;
        text-align: center;
        padding: 12px;
        justify-content: center;
    }
    
    .reader-header .font-controls {
        grid-column: 1;
        grid-row: 2;
        justify-content: center;
    }
    
    .reader-header .chapter-nav {
        grid-column: 2;
        grid-row: 2;
        justify-content: flex-end;
        gap: 8px;
    }
    
    .reader-header .nav-btn {
        padding: 12px 16px;
        font-size: 13px;
    }
    
    .reader-footer {
        flex-direction: column;
        gap: 12px;
        padding: 20px 16px;
    }
    
    .reader-footer .nav-btn {
        padding: 16px;
        font-size: 16px;
    }
    
    /* Touch-friendly */
    .novel-card,
    .chapter-item,
    .nav-btn,
    .font-btn {
        min-height: 48px;
    }
    
    .chapter-item {
        padding: 18px 20px;
    }
}

/* Progress indicator */
.reading-progress {
    position: fixed;
    right: 20px;
    bottom: 20px;
    background-color: var(--bg-card);
    border: 1px solid var(--border);
    padding: 10px 15px;
    border-radius: 20px;
    font-size: 14px;
    color: var(--text-secondary);
    z-index: 99;
    box-shadow: var(--shadow);
}

/* Back to top button */
.back-to-top {
    position: fixed;
    right: 20px;
    bottom: 70px;
    width: 45px;
    height: 45px;
    background-color: var(--accent);
    color: white;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    font-size: 20px;
    z-index: 99;
    box-shadow: var(--shadow);
    opacity: 0;
    visibility: hidden;
    transition: opacity 0.3s, visibility 0.3s, transform 0.3s;
}

.back-to-top.visible {
    opacity: 1;
    visibility: visible;
}

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

/* 完全禁用点击翻页区域，避免影响文本选择 */
.tap-zone {
    display: none !important;
    pointer-events: none !important;
}

/* Preload critical resources */
body::after {
    position: absolute;
    width: 0;
    height: 0;
    overflow: hidden;
    z-index: -1;
    content: url("https://fonts.googleapis.com/css2?family=Noto+Serif+SC:wght@400;500;600;700&display=swap");
}

/* Reduce layout shift */
.reader-content img {
    max-width: 100%;
    height: auto;
    display: block;
}

/* Better focus states for accessibility */
button:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
}

/* Touch feedback optimization */
@media (hover: none) {
    .novel-card:active,
    .chapter-item:active,
    .nav-btn:active {
        transform: scale(0.98);
    }
    
    /* Remove hover effects on touch devices */
    .novel-card:hover::before,
    .novel-card:hover,
    .chapter-item:hover,
    .font-btn:hover {
        transform: none;
    }
}

/* Performance: contain animations */
.novel-card,
.chapter-item,
.nav-btn,
.font-btn,
.back-btn,
.theme-btn {
    will-change: transform;
}

/* Reduce paint areas */
.progress-bar,
.back-to-top {
    transform: translateZ(0);
    backface-visibility: hidden;
}

/* Empty state styling */
.empty-state {
    text-align: center;
    padding: 60px 20px;
    color: var(--text-secondary);
}

.empty-state-icon {
    font-size: 48px;
    margin-bottom: 20px;
}