*{margin:0;padding:0;box-sizing:border-box;-webkit-tap-highlight-color:transparent}
html{touch-action:manipulation;-ms-touch-action:manipulation}
body{font-family:-apple-system,BlinkMacSystemFont,'Segoe UI','PingFang SC','Hiragino Sans GB','Microsoft YaHei',sans-serif;background:#f5f5f7;min-height:100vh;color:#1d1d1f;-webkit-text-size-adjust:100%;-ms-text-size-adjust:100%}
button,input,select,textarea{touch-action:manipulation}
.container{max-width:900px;margin:0 auto;padding:40px 20px}
header{display:flex;align-items:center;justify-content:space-between;margin-bottom:50px;flex-wrap:wrap;gap:20px}
.logo-container{display:flex;align-items:center;gap:12px}
.logo-container img{width:42px;height:42px;border-radius:10px}
.logo-container h1{font-size:24px;font-weight:600;color:#1d1d1f;letter-spacing:-0.5px}
.logo-container span{color:#86868b;font-size:13px;margin-left:12px;padding-left:12px;border-left:1px solid #d2d2d7}
nav{display:flex;align-items:center;gap:32px}
nav a{color:#1d1d1f;text-decoration:none;font-size:14px;font-weight:500;opacity:0.7;transition:opacity 0.2s}
nav a:hover{opacity:1}
.game-section{background:#fff;border-radius:20px;padding:40px;box-shadow:0 2px 20px rgba(0,0,0,0.06)}
.game-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:32px;flex-wrap:wrap;gap:16px}
.difficulty-selector{display:flex;gap:8px}
.difficulty-selector button{padding:8px 18px;border:none;border-radius:20px;cursor:pointer;font-size:13px;font-weight:500;transition:all 0.2s;background:#f5f5f7;color:#1d1d1f;-webkit-tap-highlight-color:transparent}
.difficulty-selector button.active{background:#1d1d1f;color:#fff}
.difficulty-selector button:active{background:#1d1d1f;color:#fff}
.game-info{display:flex;gap:24px;font-size:14px;color:#86868b}
.game-info span{display:flex;align-items:center;gap:6px;transition:all 0.3s}
.mistake-counter.error-flash{color:#ff3b30;transform:scale(1.2)}
@keyframes shake{0%,100%{transform:translateX(0)}20%,60%{transform:translateX(-4px)}40%,80%{transform:translateX(4px)}}
@keyframes correctPop{0%{transform:scale(1)}50%{transform:scale(1.15)}100%{transform:scale(1)}}
.sudoku-cell.shake{animation:shake 0.4s ease}
.sudoku-cell.correct-pop{animation:correctPop 0.3s ease}
.game-container{display:flex;justify-content:center;align-items:flex-start;gap:48px;flex-wrap:wrap}
.sudoku-board{display:grid;grid-template-columns:repeat(9,1fr);background:#1d1d1f;padding:2px;border-radius:12px;gap:1px}
.sudoku-cell{width:46px;height:46px;display:flex;align-items:center;justify-content:center;font-size:20px;font-weight:500;background:#fff;cursor:pointer;transition:all 0.15s;user-select:none;-webkit-tap-highlight-color:transparent}
.sudoku-cell:first-child{border-top-left-radius:10px}
.sudoku-cell:nth-child(9){border-top-right-radius:10px}
.sudoku-cell:nth-child(73){border-bottom-left-radius:10px}
.sudoku-cell:last-child{border-bottom-right-radius:10px}
.sudoku-cell:hover{background:#f5f5f7}
.sudoku-cell.selected{background:#007aff;color:#fff}
.sudoku-cell.fixed{color:#1d1d1f;font-weight:600}
.sudoku-cell.fixed.selected{background:#007aff;color:#fff}
.sudoku-cell.error{background:#fff;color:#ff3b30 !important}
.sudoku-cell.error.selected{background:#ffe5e5 !important;color:#ff3b30 !important}
.sudoku-cell.highlight{background:#f0f0f5}
.sudoku-cell.same-number{background:#e8e8ed}
.sudoku-cell.selected{background:#007aff;color:#fff}
.sudoku-cell:nth-child(3n):not(:nth-child(9n)){border-right:2px solid #1d1d1f}
.sudoku-cell:nth-child(9n){border-right:none}
.sudoku-cell:nth-child(n+19):nth-child(-n+27),.sudoku-cell:nth-child(n+46):nth-child(-n+54){border-bottom:2px solid #1d1d1f}

.number-pad{display:grid;grid-template-columns:repeat(3,1fr);gap:10px}
.number-pad button{width:56px;height:56px;font-size:22px;font-weight:500;border:none;border-radius:14px;cursor:pointer;background:#f5f5f7;color:#1d1d1f;transition:all 0.15s;-webkit-tap-highlight-color:transparent}
.number-pad button:hover{background:#007aff;color:#fff}
.number-pad button:active{background:#007aff;color:#fff;transform:scale(0.95)}
.action-buttons{display:flex;gap:10px;margin-top:16px}
.action-btn{flex:1;display:flex;flex-direction:column;align-items:center;gap:4px;padding:12px 8px;border:none;border-radius:12px;cursor:pointer;transition:all 0.15s;background:#f5f5f7;color:#1d1d1f;-webkit-tap-highlight-color:transparent}
.action-btn:hover,.action-btn:active{transform:translateY(-2px)}
.action-icon{font-size:20px}
.action-btn span:last-child{font-size:12px;font-weight:500}
.erase-btn{background:#fff0f0;color:#ff3b30}
.erase-btn:hover{background:#ff3b30;color:#fff}
.hint-btn{background:#fff8e6;color:#ff9500}
.hint-btn:hover{background:#ff9500;color:#fff}
.new-btn{background:#e8f4ff;color:#007aff}
.new-btn:hover{background:#007aff;color:#fff}
.controls{display:flex;gap:12px;margin-top:32px;justify-content:center}
.controls button{padding:12px 28px;border:none;border-radius:24px;cursor:pointer;font-size:14px;font-weight:500;transition:all 0.2s}
.btn-primary{background:#007aff;color:#fff}
.btn-primary:hover{background:#0071e3}
.btn-secondary{background:#34c759;color:#fff}
.btn-secondary:hover{background:#30b350}
.btn-outline{background:transparent;border:1.5px solid #d2d2d7;color:#1d1d1f}
.btn-outline:hover{background:#f5f5f7}
.content-section{margin-top:24px}
.content-section h2{font-size:24px;font-weight:600;color:#1d1d1f;margin-bottom:20px;letter-spacing:-0.3px}
.features{display:grid;grid-template-columns:repeat(4,1fr);gap:16px;margin-top:32px}
.feature-card{background:#fff;padding:24px 20px;border-radius:16px;box-shadow:0 2px 12px rgba(0,0,0,0.04);text-align:center}
.feature-card img{margin-bottom:12px}
.feature-card h3{font-size:15px;font-weight:600;color:#1d1d1f;margin-bottom:8px}
.feature-card p{font-size:13px;color:#86868b;line-height:1.5}
.seo-content{background:#fff;padding:32px;border-radius:16px;margin-top:24px;box-shadow:0 2px 12px rgba(0,0,0,0.04)}
.seo-content h2{font-size:22px;font-weight:600;color:#1d1d1f;margin-bottom:8px}
.seo-content h3{font-size:16px;font-weight:600;color:#1d1d1f;margin:28px 0 16px}
.seo-content p{font-size:14px;color:#515154;line-height:1.7;margin-bottom:12px}
.seo-content ul{padding-left:20px;margin-bottom:16px}
.seo-content li{font-size:14px;color:#515154;line-height:1.8;margin-bottom:6px}
.section-header{text-align:center;margin-bottom:24px}
.section-desc{color:#86868b;font-size:15px;margin:0}
.content-image-full{text-align:center;margin:24px 0}
.content-image-full img{max-width:100%;height:auto;border-radius:16px;box-shadow:0 8px 32px rgba(0,0,0,0.1)}
.rule-cards{display:grid;grid-template-columns:repeat(3,1fr);gap:16px;margin-top:24px}
.rule-card{display:flex;align-items:center;gap:14px;padding:16px;background:#f5f5f7;border-radius:12px}
.rule-icon{width:40px;height:40px;border-radius:10px;color:#fff;font-size:16px;font-weight:600;display:flex;align-items:center;justify-content:center;flex-shrink:0}
.rule-card h4{font-size:14px;font-weight:600;color:#1d1d1f;margin-bottom:4px}
.rule-card p{font-size:12px;color:#86868b;margin:0}
.steps{display:flex;flex-direction:column;gap:12px}
.step{display:flex;align-items:center;gap:14px;padding:14px 18px;background:#f5f5f7;border-radius:10px;font-size:14px;color:#515154}
.step span{width:28px;height:28px;background:#667eea;color:#fff;border-radius:50%;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:600;flex-shrink:0}
.tips-list{list-style:none;padding:0}
.tips-list li{padding:12px 16px;background:#f5f5f7;border-radius:10px;margin-bottom:10px;font-size:14px;color:#515154}
.tips-list li strong{color:#1d1d1f}
.benefit-box{display:flex;align-items:center;gap:14px;padding:18px 20px;background:linear-gradient(135deg,#667eea20,#764ba220);border-radius:12px;margin-top:20px}
.benefit-box span{font-size:28px}
.benefit-box p{margin:0;font-size:14px;color:#515154}
.visually-hidden{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.faq-section{margin-top:24px}
.faq-list{display:flex;flex-direction:column;gap:16px}
.faq-item{background:#f5f5f7;padding:20px 24px;border-radius:12px}
.faq-item h3{font-size:15px;font-weight:600;color:#1d1d1f;margin-bottom:10px}
.faq-item p{font-size:14px;color:#515154;line-height:1.7;margin:0}
@media(max-width:640px){.rule-cards{grid-template-columns:1fr}}
.tips-box{background:#f5f5f7;padding:16px 20px;border-radius:12px;margin-top:24px}
.tips-box h3{font-size:13px;font-weight:600;color:#1d1d1f;margin-bottom:10px}
.tips-box ul{list-style:none;padding:0}
.tips-box li{font-size:12px;color:#86868b;margin-bottom:4px;display:flex;gap:6px}
.tips-box li::before{content:"⌨";opacity:0.5}
footer{text-align:center;padding:40px 20px;margin-top:48px;color:#86868b;font-size:13px}
footer a{color:#515154;text-decoration:none}
footer a:hover{text-decoration:underline}
footer p{margin:4px 0}
.modal{display:none;position:fixed;top:0;left:0;width:100%;height:100%;background:rgba(0,0,0,0.4);backdrop-filter:blur(8px);z-index:1000;align-items:center;justify-content:center}
.modal.show{display:flex}
.modal-content{background:#fff;padding:32px;border-radius:24px;text-align:center;max-width:420px;animation:modalIn 0.25s ease-out}
.modal-content h2{font-size:24px;font-weight:600;color:#1d1d1f;margin-bottom:8px}
.modal-content p{font-size:16px;color:#86868b;margin-bottom:20px}
.modal-buttons{display:flex;gap:12px;justify-content:center;flex-wrap:wrap;margin-top:20px}
.modal-buttons .btn-primary{padding:14px 32px;border-radius:50px;font-size:15px;font-weight:500}
.modal-buttons .btn-secondary{padding:14px 32px;border-radius:50px;font-size:15px;font-weight:500;background:#f5f5f7;color:#1d1d1f}
.modal-buttons .btn-secondary:hover{background:#e8e8ed}
#share-card{margin:16px 0}
#share-card canvas{max-width:100%;border-radius:16px;box-shadow:0 8px 32px rgba(0,0,0,0.12)}
#confetti-container{position:fixed;top:0;left:0;width:100%;height:100%;pointer-events:none;z-index:9999;overflow:hidden}
.confetti{position:absolute;border-radius:50%;animation:explode 1s ease-out forwards}
@keyframes explode{0%{transform:translate(0,0) scale(1);opacity:1}100%{transform:translate(var(--tx),var(--ty)) scale(0);opacity:0}}
@media(max-width:768px){
.container{padding:10px}
header{flex-direction:row;justify-content:space-between;align-items:center;margin-bottom:8px;gap:0}
nav{gap:14px}
nav a{font-size:12px}
.logo-container{gap:8px}
.logo-container img{width:28px;height:28px}
.logo-container h1{font-size:16px}
.logo-container span{display:none}
.game-section{padding:10px;border-radius:12px}
.game-header{flex-direction:row;justify-content:space-between;align-items:center;gap:8px;margin-bottom:8px}
.difficulty-selector{gap:4px}
.difficulty-selector button{padding:5px 8px;font-size:10px}
.game-info{gap:10px;font-size:11px}
.game-container{gap:8px;flex-direction:column;align-items:center}
.sudoku-board{width:calc(100vw - 44px);max-width:340px}
.sudoku-cell{width:calc((100vw - 68px) / 9);height:calc((100vw - 68px) / 9);max-width:36px;max-height:36px;font-size:16px}
.number-pad{gap:6px;width:calc(100vw - 44px);max-width:340px;margin:0 auto;grid-template-columns:repeat(3,1fr)}
.number-pad button{width:100%;height:52px;padding:0;font-size:22px;border-radius:10px}
.action-buttons{width:calc(100vw - 44px);max-width:340px;margin:6px auto 0;gap:6px}
.action-btn{padding:14px 4px;border-radius:10px;flex-direction:row;gap:4px;justify-content:center}
.action-icon{font-size:15px}
.action-btn span:last-child{font-size:12px}
.tips-box{display:none}
.features{grid-template-columns:repeat(2,1fr);gap:10px;margin-top:16px}
.feature-card{padding:12px 10px}
.feature-card img{width:32px;height:32px;margin-bottom:6px}
.feature-card h3{font-size:12px;margin-bottom:2px}
.feature-card p{font-size:10px}
.seo-content{padding:16px 12px;margin-top:12px}
.seo-content h2{font-size:16px}
.seo-content h3{font-size:14px;margin:16px 0 10px}
.section-header{margin-bottom:12px}
.section-desc{font-size:12px}
.rule-cards{grid-template-columns:1fr;gap:8px}
.rule-card{padding:10px}
.rule-icon{width:32px;height:32px;font-size:12px}
.rule-card h4{font-size:12px}
.rule-card p{font-size:10px}
.steps{gap:6px}
.step{padding:10px 12px;font-size:12px;gap:8px}
.step span{width:22px;height:22px;font-size:11px}
.tips-list li{padding:8px 10px;font-size:12px;margin-bottom:6px}
.benefit-box{padding:12px;gap:8px}
.benefit-box span{font-size:18px}
.benefit-box p{font-size:12px}
.faq-item{padding:12px}
.faq-item h3{font-size:13px;margin-bottom:6px}
.faq-item p{font-size:12px}
.content-image-full img{border-radius:10px}
footer{padding:20px 12px;margin-top:20px;font-size:11px}
.modal-content{margin:12px;padding:20px 16px;max-width:calc(100vw - 24px)}
.modal-content h2{font-size:18px}
.modal-buttons{flex-direction:column;gap:8px}
.modal-buttons .btn-primary,.modal-buttons .btn-secondary{width:100%;padding:12px 16px;font-size:14px}
#share-card canvas{max-height:50vh}
}
@media(max-width:380px){
.sudoku-cell{font-size:14px}
.number-pad button{height:32px;font-size:16px}
.difficulty-selector button{padding:4px 6px;font-size:9px}
.logo-container h1{font-size:14px}
nav a{font-size:11px}
}

.difficulty-table{background:#f5f5f7;border-radius:12px;overflow:hidden}
.diff-row{display:grid;grid-template-columns:1fr 1fr 1.5fr 1fr;padding:14px 16px;border-bottom:1px solid #e5e5e5;font-size:13px;color:#515154}
.diff-row:last-child{border-bottom:none}
.diff-header{background:#1d1d1f;color:#fff;font-weight:600;font-size:12px}
.diff-label{font-weight:600;padding:4px 10px;border-radius:12px;font-size:11px;display:inline-block}
.easy-label{background:#34c75920;color:#34c759}
.medium-label{background:#007aff20;color:#007aff}
.hard-label{background:#ff950020;color:#ff9500}
.expert-label{background:#ff3b3020;color:#ff3b30}
.glossary-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:12px}
.glossary-item{background:#f5f5f7;padding:16px;border-radius:10px}
.glossary-item h4{font-size:14px;font-weight:600;color:#1d1d1f;margin-bottom:6px}
.glossary-item p{font-size:12px;color:#86868b;margin:0;line-height:1.5}
.history-content p{font-size:14px;color:#515154;line-height:1.8;margin-bottom:16px}
.history-timeline{display:flex;justify-content:space-between;margin-top:24px;padding:20px;background:#f5f5f7;border-radius:12px}
.timeline-item{text-align:center}
.timeline-item .year{display:block;font-size:18px;font-weight:700;color:#667eea;margin-bottom:4px}
.timeline-item .event{font-size:12px;color:#86868b}
.benefits-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:16px}
.benefit-card{background:#f5f5f7;padding:20px;border-radius:12px;text-align:center}
.benefit-icon{font-size:32px;display:block;margin-bottom:10px}
.benefit-card h4{font-size:14px;font-weight:600;color:#1d1d1f;margin-bottom:8px}
.benefit-card p{font-size:12px;color:#86868b;line-height:1.5;margin:0}
.daily-tip-section{background:linear-gradient(135deg,#667eea,#764ba2);padding:24px !important}
.daily-tip{display:flex;align-items:center;gap:16px;color:#fff}
.tip-icon{font-size:36px}
.tip-content h4{font-size:14px;font-weight:600;margin-bottom:6px}
.tip-content p{font-size:13px;opacity:0.9;margin:0;line-height:1.6}
@media(max-width:768px){
.diff-row{grid-template-columns:1fr 1fr;gap:4px;font-size:11px;padding:10px 12px}
.diff-header span:nth-child(3),.diff-header span:nth-child(4),.diff-row span:nth-child(3),.diff-row span:nth-child(4){display:none}
.glossary-grid{grid-template-columns:repeat(2,1fr);gap:8px}
.glossary-item{padding:12px}
.glossary-item h4{font-size:13px}
.glossary-item p{font-size:11px}
.history-timeline{flex-wrap:wrap;gap:16px;justify-content:center}
.timeline-item{width:45%}
.benefits-grid{grid-template-columns:repeat(2,1fr);gap:10px}
.benefit-card{padding:14px}
.benefit-icon{font-size:24px;margin-bottom:6px}
.benefit-card h4{font-size:13px;margin-bottom:4px}
.benefit-card p{font-size:11px}
.daily-tip{flex-direction:column;text-align:center;gap:10px}
.tip-icon{font-size:28px}
}


.game-links{display:grid;grid-template-columns:repeat(4,1fr);gap:16px}
.game-link-card{display:block;background:#f5f5f7;padding:24px 16px;border-radius:12px;text-align:center;text-decoration:none;transition:all 0.2s}
.game-link-card:hover{transform:translateY(-4px);box-shadow:0 8px 24px rgba(0,0,0,0.1)}
.game-link-card span{font-size:36px;display:block;margin-bottom:8px}
.game-link-card h4{font-size:15px;color:#1d1d1f;margin-bottom:4px}
.game-link-card p{font-size:12px;color:#86868b;margin:0}
@media(max-width:768px){
.game-links{grid-template-columns:repeat(2,1fr);gap:10px}
.game-link-card{padding:16px 12px}
.game-link-card span{font-size:28px}
}


.cover-image{margin:24px 0 0;text-align:center}
.cover-image img{width:100%;max-width:800px;height:auto;border-radius:12px;box-shadow:0 4px 20px rgba(0,0,0,0.1)}
@media(max-width:768px){
.cover-image{margin:16px 0 0}
.cover-image img{border-radius:8px}
}