/* CSS变量定义 - 主题系统 */
:root {
    --transition: all 0.3s ease;
}

/* Printable Sudoku Styles */
.preview-section {
    margin-bottom: 30px;
}

.preview-container {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 0.5mm;
    padding: 0;
    background: transparent;
    min-height: auto;
    overflow: visible;
}

.puzzle-page {
    width: 210mm;
    height: 297mm;
    background: white;
    padding: 3mm;
    box-sizing: border-box;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    border-radius: var(--border-radius);
    display: flex;
    flex-direction: column;
    page-break-after: always;
    transform: scale(0.8);
    transform-origin: center;
    overflow: hidden;
    flex-shrink: 0;
    position: relative;
}

.page-title {
    text-align: center;
    font-size: 14px;
    font-weight: bold;
    margin-bottom: 10mm;
    color: #333;
}

.puzzles-grid {
    flex: 1;
    display: grid;
    gap: 1mm;
    align-items: center;
    justify-items: center;
    width: 100%;
    height: 100%;
    padding: 2mm;
    box-sizing: border-box;
}

.sudoku-grid {
    display: grid;
    border: 2px solid #000;
    background: #000;
    margin: 0 auto;
    gap: 1px;
}

.sudoku-cell {
    border: none;
    display: flex;
    align-items: center;
    justify-content: center;
    font-weight: bold;
    color: #000;
    background: white;
    box-sizing: border-box;
    aspect-ratio: 1;
    min-height: 0;
    min-width: 0;
}

.puzzle-number {
    text-align: center;
    font-size: 10px;
    color: #666;
    margin-top: 2mm;
}

.domain-watermark {
    position: absolute;
    bottom: 2mm;
    right: 3mm;
    font-size: 12px;
    color: #666;
    font-family: Arial, sans-serif;
    opacity: 0.8;
    font-weight: 500;
    letter-spacing: 0.3px;
}

/* Responsive scaling for different screen sizes */
@media (max-width: 1200px) {
    .puzzle-page {
        transform: scale(0.7);
    }
}

@media (max-width: 768px) {
    .puzzle-page {
        transform: scale(0.55);
    }
    
    .preview-container {
        padding: 10px;
    }
}

@media (max-width: 480px) {
    .puzzle-page {
        transform: scale(0.45);
    }
}

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

/* Section scroll padding */
#number-game,
#game-guide,
#features-section,
#faq-section {
    scroll-margin-top: 20px;
}

/* Page Header Styles */
.page-header {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 30px;
    background: var(--container-bg);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border-bottom: 2px solid var(--timer-color);
    margin-bottom: 20px;
}

.logo-section {
    display: flex;
    align-items: center;
    gap: 12px;
}

.favicon-logo {
    display: flex;
    align-items: center;
}

.site-title {
    margin: 0;
    font-size: 1.8rem;
    font-weight: 700;
    color: var(--timer-color);
    font-family: var(--font-family);
}

.main-nav {
    display: flex;
    gap: 30px;
    align-items: center;
}

.nav-link {
    color: var(--text-color);
    text-decoration: none;
    font-weight: 600;
    font-size: 1.1rem;
    padding: 8px 16px;
    border-radius: var(--border-radius);
    transition: var(--transition);
    border: 2px solid transparent;
}

.nav-link:hover {
    color: var(--timer-color);
    background: rgba(0, 0, 0, 0.05);
    border-color: var(--timer-color);
}

/* Mobile responsive header */
@media (max-width: 768px) {
    .page-header {
        flex-direction: column;
        gap: 15px;
        padding: 15px 20px;
    }
    
    .main-nav {
        gap: 20px;
        flex-wrap: wrap;
        justify-content: center;
    }
    
    .nav-link {
        font-size: 1rem;
        padding: 6px 12px;
    }
    
    .site-title {
        font-size: 1.5rem;
    }
}

@media (max-width: 480px) {
    .page-header {
        padding: 10px 15px;
    }
    
    .main-nav {
        gap: 15px;
    }
    
    .nav-link {
        font-size: 0.9rem;
        padding: 5px 10px;
    }
    
    .site-title {
        font-size: 1.3rem;
    }
    
    .favicon-logo svg {
        width: 32px;
        height: 32px;
    }
}

/* 经典主题 */
.theme-classic {
    --bg-gradient: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    --container-bg: rgba(255, 255, 255, 0.95);
    --text-color: #333;
    --btn-bg: linear-gradient(135deg, #4CAF50, #45a049);
    --btn-color: white;
    --cell-bg: white;
    --cell-border: #333;
    --cell-focus-bg: #e3f2fd;
    --cell-focus-border: #2196F3;
    --cell-highlight-bg: #fff3cd;
    --cell-error-bg: #ffebee;
    --cell-error-color: #d32f2f;
    --cell-given-bg: #f5f5f5;
    --timer-color: #4CAF50;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --border-radius: 8px;
    --container-radius: 15px;
}

/* 像素主题 - 马里奥风格 */
.theme-pixel {
    --bg-gradient: linear-gradient(135deg, #87CEEB 0%, #98FB98 50%, #FFB6C1 100%);
    --container-bg: #FFF8DC;
    --text-color: #8B0000;
    --btn-bg: linear-gradient(135deg, #FF4500, #FF6347);
    --btn-color: white;
    --cell-bg: #FFFACD;
    --cell-border: #8B4513;
    --cell-focus-bg: #FF1493;
    --cell-focus-border: #DC143C;
    --cell-highlight-bg: #FFD700;
    --cell-error-bg: #FF4500;
    --cell-error-color: white;
    --cell-given-bg: #DDA0DD;
    --timer-color: #FF4500;
    --font-family: 'Courier New', monospace;
    --border-radius: 0px;
    --container-radius: 0px;
}

/* 暗色主题 */
.theme-dark {
    --bg-gradient: linear-gradient(135deg, #1a1a1a 0%, #2d2d2d 100%);
    --container-bg: rgba(45, 45, 45, 0.95);
    --text-color: #e0e0e0;
    --btn-bg: linear-gradient(135deg, #6200ea, #3700b3);
    --btn-color: white;
    --cell-bg: #424242;
    --cell-border: #9e9e9e;
    --cell-focus-bg: #1976d2;
    --cell-focus-border: #1565c0;
    --cell-highlight-bg: #ff8f00;
    --cell-error-bg: #d32f2f;
    --cell-error-color: white;
    --cell-given-bg: #616161;
    --timer-color: #00e676;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --border-radius: 12px;
    --container-radius: 20px;
}

/* 彩虹主题 */
.theme-rainbow {
    --bg-gradient: linear-gradient(135deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #fcea2b);
    --container-bg: rgba(255, 255, 255, 0.9);
    --text-color: #2c3e50;
    --btn-bg: linear-gradient(135deg, #ff6b6b, #ff8e53);
    --btn-color: white;
    --cell-bg: white;
    --cell-border: #2c3e50;
    --cell-focus-bg: #ff6b6b;
    --cell-focus-border: #e55353;
    --cell-highlight-bg: #4ecdc4;
    --cell-error-bg: #ff6b6b;
    --cell-error-color: white;
    --cell-given-bg: #f8f9fa;
    --timer-color: #ff6b6b;
    --font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    --border-radius: 15px;
    --container-radius: 25px;
}

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

body {
    font-family: var(--font-family);
    background: var(--bg-gradient);
    background-attachment: fixed;
    min-height: 100vh;
    padding: 10px;
    color: var(--text-color);
    transition: var(--transition);
}

.container {
    max-width: 600px;
    margin: 0 auto;
    background: var(--container-bg);
    border-radius: var(--container-radius);
    padding: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.3);
    transition: var(--transition);
}

header {
    text-align: center;
    margin-bottom: 20px;
}

h1 {
    color: var(--text-color);
    font-size: 2rem;
    margin-bottom: 15px;
    font-family: var(--font-family);
}

.controls {
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
}

.btn {
    background: var(--btn-bg);
    color: var(--btn-color);
    border: none;
    padding: 10px 20px;
    border-radius: var(--border-radius);
    cursor: pointer;
    font-size: 14px;
    font-family: var(--font-family);
    transition: var(--transition);
    font-weight: 600;
}

.btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.2);
}

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

.game-info {
    display: flex;
    justify-content: space-between;
    align-items: center;
    margin-bottom: 20px;
    padding: 15px;
    background: var(--container-bg);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    flex-wrap: wrap;
    gap: 10px;
}

.difficulty label,
.theme-selector label {
    font-weight: 600;
    color: var(--text-color);
    font-family: var(--font-family);
}

select {
    padding: 5px 10px;
    border: 2px solid var(--cell-border);
    border-radius: var(--border-radius);
    margin-left: 5px;
    background: var(--cell-bg);
    color: var(--text-color);
    font-family: var(--font-family);
    transition: var(--transition);
}

select:focus {
    outline: none;
    border-color: var(--cell-focus-border);
}

.timer {
    font-weight: 600;
    color: var(--text-color);
    font-family: var(--font-family);
}

#timer {
    color: var(--timer-color);
    font-size: 1.1em;
    font-weight: bold;
}

.sudoku-container {
    display: flex;
    justify-content: center;
    align-items: center;
    margin-bottom: 20px;
    padding: 10px;
}

.sudoku-grid {
    display: grid;
    /* 动态设置网格行列数 */
    gap: 2px;
    background-color: var(--cell-border);
    border: 4px solid var(--cell-border);
    border-radius: var(--border-radius);
    width: min(450px, 90vw);
    height: min(450px, 90vw);
    max-width: 450px;
    max-height: 450px;
    box-shadow: 0 8px 20px rgba(0, 0, 0, 0.3);
}

.cell {
    background-color: var(--cell-bg);
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 1.2rem;
    font-weight: bold;
    cursor: pointer;
    transition: var(--transition);
    border: none;
    outline: none;
    width: 100%;
    height: 100%;
    text-align: center;
    color: var(--text-color);
    font-family: var(--font-family);
}

.cell:focus {
    background-color: var(--cell-focus-bg) !important;
    box-shadow: inset 0 0 0 2px var(--cell-focus-border);
    color: white !important;
}

.cell.highlighted {
    background-color: var(--cell-highlight-bg) !important;
}

.cell.error {
    background-color: var(--cell-error-bg) !important;
    color: var(--cell-error-color) !important;
    animation: shake 0.5s ease-in-out;
}

.cell.given {
    background-color: var(--cell-given-bg) !important;
    cursor: default;
    font-weight: 900;
}

/* 区域边框 - 动态适应不同尺寸的数独网格 */
/* 这些样式将通过JavaScript动态添加 */

/* 移除交替背景色 - 简化设计，避免显示问题 */

/* 像素主题特殊效果 - 马里奥风格 */
.theme-pixel .cell {
    border: 3px solid var(--cell-border);
    font-weight: 900;
    color: #654321 !important;
    text-shadow: 2px 2px 0 #FFFFFF, -1px -1px 0 rgba(255, 255, 255, 0.8);
    box-shadow: inset -2px -2px 0 rgba(0, 0, 0, 0.2), inset 2px 2px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel .cell:hover {
    transform: translateY(-1px);
    box-shadow: inset -2px -2px 0 rgba(0, 0, 0, 0.3), inset 2px 2px 0 rgba(255, 255, 255, 1), 0 3px 6px rgba(0, 0, 0, 0.2);
}

.theme-pixel .cell:active {
    transform: translateY(1px);
    box-shadow: inset 2px 2px 0 rgba(0, 0, 0, 0.3), inset -2px -2px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel .cell.given {
    background: linear-gradient(135deg, #DDA0DD, #DA70D6);
    border-color: #8B008B;
    color: #654321 !important;
    font-weight: 900;
    text-shadow: 1px 1px 0 #FFFFFF, -1px -1px 0 rgba(255, 255, 255, 0.8);
    box-shadow: inset -3px -3px 0 rgba(139, 0, 139, 0.3), inset 3px 3px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel .sudoku-grid {
    border-width: 6px;
    border-style: solid;
    gap: 2px;
    box-shadow: 
        0 0 0 3px #654321,
        0 8px 16px rgba(0, 0, 0, 0.3);
}

/* 像素主题的区域强化分割 - 动态适应 */
/* 这些样式将通过JavaScript动态添加 */

.theme-pixel .btn {
    border: 3px solid #8B4513;
    text-transform: uppercase;
    letter-spacing: 2px;
    font-weight: 900;
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.5), 
        inset 3px 3px 0 rgba(255, 255, 255, 0.8),
        0 4px 8px rgba(0, 0, 0, 0.2);
    transition: all 0.1s ease;
}

.theme-pixel .btn:hover {
    transform: translateY(-2px);
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.5), 
        inset 3px 3px 0 rgba(255, 255, 255, 1),
        0 6px 12px rgba(0, 0, 0, 0.3);
}

.theme-pixel .btn:active {
    transform: translateY(0);
    box-shadow: 
        inset 3px 3px 0 rgba(139, 69, 19, 0.5), 
        inset -3px -3px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel h1 {
    text-transform: uppercase;
    letter-spacing: 3px;
    font-size: 2.5rem;
    color: #FF4500;
    text-shadow: 
        3px 3px 0 #FFFFFF,
        -2px -2px 0 #8B0000,
        4px 4px 8px rgba(0, 0, 0, 0.5);
    animation: pixelBounce 2s ease-in-out infinite;
}

.theme-pixel .container {
    border: 4px solid #8B4513;
    box-shadow: 
        inset -4px -4px 0 rgba(139, 69, 19, 0.3), 
        inset 4px 4px 0 rgba(255, 255, 255, 0.8),
        0 12px 24px rgba(0, 0, 0, 0.3);
}

.theme-pixel .game-info {
    background: linear-gradient(135deg, #FFE4B5, #FFDAB9);
    border: 3px solid #8B4513;
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.3), 
        inset 3px 3px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel select {
    border: 2px solid #8B4513;
    background: linear-gradient(135deg, #FFFACD, #F0E68C);
    font-weight: bold;
    box-shadow: inset -2px -2px 0 rgba(139, 69, 19, 0.3), inset 2px 2px 0 rgba(255, 255, 255, 0.8);
}

/* 像素主题区域区分 - 清晰的背景和加强的边框 */
.theme-pixel .cell:not(.given) { 
    background: var(--cell-bg) !important; 
}

/* 增强区域边框分割效果 */
.theme-pixel .cell {
    border: 2px solid var(--cell-border) !important;
}

.theme-pixel .sudoku-grid {
    border: 8px solid var(--cell-border) !important;
    background: #654321;
    gap: 3px !important;
}

/* 加强子区域边框的可见性 - 使用更深的颜色 */
.theme-pixel .cell[style*="border-right"] {
    border-right: 6px solid #654321 !important;
    box-shadow: 3px 0 0 0 #654321 !important;
}

.theme-pixel .cell[style*="border-bottom"] {
    border-bottom: 6px solid #654321 !important;
    box-shadow: 0 3px 0 0 #654321 !important;
}

/* 同时有右边框和下边框的角落格子 */
.theme-pixel .cell[style*="border-right"][style*="border-bottom"] {
    box-shadow: 3px 0 0 0 #654321, 0 3px 0 0 #654321, 3px 3px 0 0 #654321 !important;
}

/* 像素主题的交替背景以区分区域 */
.theme-pixel .cell:not(.given) {
    background: var(--cell-bg) !important;
}

/* 为不同区域添加微妙的背景色差异 */
.theme-pixel .cell.box-even:not(.given) {
    background: #F5F5DC !important;
}

@keyframes pixelBounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(-5px); }
}

/* 彩虹主题特殊效果 */
.theme-rainbow .cell:nth-child(9n+1) { border-left: 3px solid #ff6b6b; }
.theme-rainbow .cell:nth-child(9n+2) { border-left: 3px solid #ff8e53; }
.theme-rainbow .cell:nth-child(9n+3) { border-left: 3px solid #feca57; }
.theme-rainbow .cell:nth-child(9n+4) { border-left: 3px solid #48cab2; }
.theme-rainbow .cell:nth-child(9n+5) { border-left: 3px solid #4834d4; }
.theme-rainbow .cell:nth-child(9n+6) { border-left: 3px solid #8c7ae6; }
.theme-rainbow .cell:nth-child(9n+7) { border-left: 3px solid #e056fd; }
.theme-rainbow .cell:nth-child(9n+8) { border-left: 3px solid #ff3838; }
.theme-rainbow .cell:nth-child(9n+9) { border-left: 3px solid #ff9ff3; }

.theme-rainbow h1 {
    background: linear-gradient(135deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #fcea2b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

@keyframes shake {
    0%, 100% { transform: translateX(0); }
    25% { transform: translateX(-5px); }
    75% { transform: translateX(5px); }
}

.message {
    text-align: center;
    padding: 15px;
    border-radius: var(--border-radius);
    font-weight: bold;
    margin-top: 10px;
    opacity: 0;
    transition: var(--transition);
    font-family: var(--font-family);
}

.message.show {
    opacity: 1;
}

.message.success {
    background-color: rgba(76, 175, 80, 0.2);
    color: var(--timer-color);
    border: 2px solid var(--timer-color);
}

.message.error {
    background-color: rgba(244, 67, 54, 0.2);
    color: var(--cell-error-color);
    border: 2px solid var(--cell-error-color);
}

/* 响应式设计 */
@media (max-width: 480px) {
    body {
        padding: 5px;
    }
    
    .container {
        padding: 15px;
    }
    
    h1 {
        font-size: 1.5rem;
    }
    
    .controls {
        gap: 8px;
    }
    
    .btn {
        padding: 8px 16px;
        font-size: 13px;
    }
    
    .game-info {
        flex-direction: column;
        gap: 10px;
        text-align: center;
    }
    
    .cell {
        font-size: 1rem;
    }
    
    .sudoku-grid {
        width: min(90vw, 350px);
        height: min(90vw, 350px);
        max-width: 350px;
        max-height: 350px;
    }
    
    .sudoku-container {
        padding: 5px;
    }
}

@media (max-width: 360px) {
    .cell {
        font-size: 0.9rem;
    }
    
    .sudoku-grid {
        width: min(85vw, 280px);
        height: min(85vw, 280px);
        max-width: 280px;
        max-height: 280px;
    }
    
    .container {
        padding: 10px;
    }
    
    .game-info {
        padding: 10px;
    }
}

/* 大网格特殊样式 */
@media (min-width: 768px) {
    /* 10x10和16x16网格的优化 */
    .sudoku-grid {
        gap: 1px;
    }
    
    .cell {
        min-height: 25px;
    }
}

@media (max-width: 767px) {
    /* 移动设备上大网格的特殊处理 */
    .sudoku-grid {
        gap: 1px;
    }
    
    .cell {
        min-height: 20px;
        font-size: 0.6rem !important;
    }
    
    .container {
        padding: 5px;
        margin: 5px;
    }
    
    .game-info {
        flex-direction: column;
        text-align: center;
        padding: 8px;
        gap: 8px;
    }
    
    .game-info > div {
        margin-bottom: 5px;
    }
}

/* 游戏指南样式 */
.game-guide {
    margin-top: 30px;
    padding: 20px;
    background: var(--container-bg);
    border-radius: var(--border-radius);
    border: 2px solid var(--cell-border);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.game-guide h2 {
    color: var(--text-color);
    font-size: 1.8rem;
    text-align: center;
    margin-bottom: 25px;
    font-family: var(--font-family);
    border-bottom: 3px solid var(--timer-color);
    padding-bottom: 10px;
}

.guide-section {
    margin-bottom: 25px;
}

.guide-section h3 {
    color: var(--timer-color);
    font-size: 1.3rem;
    margin-bottom: 15px;
    font-family: var(--font-family);
    border-left: 4px solid var(--timer-color);
    padding-left: 12px;
}

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

.guide-section li {
    color: var(--text-color);
    margin-bottom: 8px;
    padding: 8px 12px;
    background: rgba(0, 0, 0, 0.03);
    border-radius: var(--border-radius);
    border-left: 3px solid var(--cell-highlight-bg);
    font-family: var(--font-family);
    line-height: 1.5;
}

.guide-section li strong {
    color: var(--timer-color);
}

.technique {
    background: rgba(0, 0, 0, 0.05);
    padding: 15px;
    margin-bottom: 15px;
    border-radius: var(--border-radius);
    border: 2px solid var(--cell-highlight-bg);
}

.technique h4 {
    color: var(--text-color);
    font-size: 1.1rem;
    margin-bottom: 8px;
    font-family: var(--font-family);
}

.technique p {
    color: var(--text-color);
    margin: 0;
    font-family: var(--font-family);
    line-height: 1.6;
}

/* 主题特化样式 */
.theme-pixel .game-guide {
    border-width: 4px;
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.3), 
        inset 3px 3px 0 rgba(255, 255, 255, 0.8),
        0 8px 16px rgba(0, 0, 0, 0.2);
}

.theme-pixel .guide-section li {
    border-width: 2px;
    border-style: solid;
    box-shadow: inset -2px -2px 0 rgba(0, 0, 0, 0.2), inset 2px 2px 0 rgba(255, 255, 255, 0.8);
}

.theme-pixel .technique {
    border-width: 3px;
    border-style: solid;
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.3), 
        inset 3px 3px 0 rgba(255, 255, 255, 0.8);
}

.theme-rainbow .game-guide h2 {
    background: linear-gradient(135deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #fcea2b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.theme-dark .guide-section li {
    background: rgba(255, 255, 255, 0.05);
}

.theme-dark .technique {
    background: rgba(255, 255, 255, 0.08);
}

@media (max-width: 480px) {
    .game-guide {
        margin-top: 20px;
        padding: 15px;
    }
    
    .game-guide h2 {
        font-size: 1.5rem;
    }
    
    .guide-section h3 {
        font-size: 1.1rem;
    }
    
    .technique {
        padding: 12px;
    }
    
    .guide-section li {
        padding: 6px 10px;
        font-size: 0.9rem;
    }
}

/* 页脚样式 */
.footer {
    margin-top: 40px;
    padding: 20px 10px;
    background: var(--container-bg);
    border-top: 3px solid var(--timer-color);
    text-align: center;
}

.footer-content {
    max-width: 600px;
    margin: 0 auto;
}

.footer-section {
    margin-bottom: 10px;
}

.footer-section p {
    color: var(--text-color);
    font-family: var(--font-family);
    font-weight: 600;
    margin: 0;
}

.footer-links {
    margin: 15px 0;
}

.footer-links a {
    color: var(--timer-color);
    text-decoration: none;
    font-family: var(--font-family);
    font-weight: 500;
    transition: var(--transition);
}

.footer-links a:hover {
    text-decoration: underline;
    color: var(--cell-focus-border);
}

.separator {
    color: var(--text-color);
    margin: 0 10px;
}

.footer-info p {
    color: var(--text-color);
    font-family: var(--font-family);
    font-size: 0.9rem;
    margin: 0;
    opacity: 0.8;
}

/* 主题特化页脚样式 */
.theme-pixel .footer {
    border-top-width: 4px;
    border-top-style: solid;
    box-shadow: 
        inset -3px -3px 0 rgba(139, 69, 19, 0.3), 
        inset 3px 3px 0 rgba(255, 255, 255, 0.8);
}

.theme-rainbow .footer-section p {
    background: linear-gradient(135deg, #ff6b6b, #4ecdc4, #45b7d1, #96ceb4, #fcea2b);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

@media (max-width: 480px) {
    .footer {
        margin-top: 30px;
        padding: 15px 5px;
    }
    
    .footer-links {
        flex-direction: column;
        gap: 10px;
    }
    
    .separator {
        display: none;
    }
    
    .footer-info p {
        font-size: 0.8rem;
    }
}

/* FAQ Section Styles */
.faq-section {
    margin-top: 40px;
    max-width: 100%;
}

.faq-item {
    margin-bottom: 20px;
    padding: 20px;
    background: var(--container-bg);
    border-radius: var(--border-radius);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    border-left: 4px solid var(--timer-color);
}

.faq-question {
    color: var(--timer-color);
    font-weight: 600;
    margin-bottom: 10px;
    font-size: 1.1rem;
}

.faq-answer {
    color: var(--text-color);
    line-height: 1.6;
    font-size: 1rem;
}

@media (max-width: 768px) {
    .faq-section {
        margin-top: 30px;
    }
    
    .faq-item {
        padding: 15px;
        margin-bottom: 15px;
    }
    
    .faq-question {
        font-size: 1rem;
    }
    
    .faq-answer {
        font-size: 0.9rem;
    }
}