/* ===== CSS Reset & Base ===== */
*,*::before,*::after{box-sizing:border-box;margin:0;padding:0}
html{font-size:16px;scroll-behavior:smooth}
body{font-family:"PingFang SC","Hiragino Sans GB","Microsoft YaHei","WenQuanYi Micro Hei",sans-serif;color:#212121;background:#f5f5f5;line-height:1.8}
img{max-width:100%;height:auto;display:block}
a{color:#1A237E;text-decoration:none;transition:color .3s}
a:hover{color:#FF6F00}
ul,ol{list-style:none}
h1,h2,h3,h4,h5,h6{font-family:"PingFang SC","Microsoft YaHei",sans-serif;font-weight:700;color:#1A237E;line-height:1.4}
h1{font-size:2rem;margin-bottom:1rem}
h2{font-size:1.6rem;margin-bottom:.8rem}
h3{font-size:1.3rem;margin-bottom:.6rem}
h4{font-size:1.1rem;margin-bottom:.5rem}
p{margin-bottom:1rem;color:#333}

/* ===== Layout ===== */
.container{max-width:1200px;margin:0 auto;padding:0 20px}
.section{padding:60px 0}
.section-alt{background:#fff}

/* ===== Header / Navigation ===== */
.site-header{background:#1A237E;padding:15px 0;position:relative;z-index:100}
.header-inner{display:flex;align-items:center;justify-content:space-between;flex-wrap:wrap}
.site-logo{display:flex;align-items:center;gap:10px}
.site-logo img{height:40px;width:auto}
.site-logo span{color:#fff;font-size:1.2rem;font-weight:700}
.nav-toggle{display:none;background:none;border:none;color:#fff;font-size:1.5rem;cursor:pointer;padding:5px}
.main-nav ul{display:flex;gap:5px;flex-wrap:wrap}
.main-nav a{color:#fff;padding:8px 14px;border-radius:4px;font-size:.9rem;transition:background .3s}
.main-nav a:hover,.main-nav a.active{background:#FF6F00;color:#fff}
.dropdown{position:relative}
.dropdown-menu{display:none;position:absolute;top:100%;left:0;background:#283593;min-width:220px;border-radius:0 0 8px 8px;box-shadow:0 4px 12px rgba(0,0,0,.3);z-index:200;padding:8px 0}
.dropdown:hover .dropdown-menu{display:block}
.dropdown-menu a{display:block;padding:10px 18px;color:#fff;font-size:.85rem}
.dropdown-menu a:hover{background:#FF6F00}

@media(max-width:768px){
  .nav-toggle{display:block}
  .main-nav{width:100%;order:3}
  .main-nav.closed ul{display:none}
  .main-nav.open ul{display:flex;flex-direction:column;width:100%;padding-top:10px}
  .main-nav a{display:block;padding:10px 14px}
  .dropdown-menu{position:static;box-shadow:none;padding-left:20px}
  .dropdown:hover .dropdown-menu{display:none}
  .dropdown.open .dropdown-menu{display:block}
}

/* ===== Breadcrumb ===== */
.breadcrumb{padding:12px 0;font-size:.85rem;color:#666}
.breadcrumb a{color:#1A237E}
.breadcrumb span{margin:0 6px;color:#999}

/* ===== Hero / Blackboard ===== */
.hero-blackboard{background:#2d2d2d;position:relative;padding:80px 20px;text-align:center;overflow:hidden;border-bottom:8px solid #5d4037}
.hero-blackboard::before{content:"";position:absolute;top:0;left:0;right:0;bottom:0;background:repeating-linear-gradient(0deg,transparent,transparent 2px,rgba(255,255,255,.02) 2px,rgba(255,255,255,.02) 4px)}
.hero-blackboard h1{color:#fff;font-size:2.2rem;text-shadow:2px 2px 4px rgba(0,0,0,.5);animation:chalkWrite 1.5s ease-out}
.hero-blackboard .chalk-text{color:#e0e0e0;font-size:1.1rem;margin-top:15px;font-style:italic;animation:chalkWrite 2s ease-out}
.hero-blackboard .highlight{color:#FF6F00;font-weight:700}

@keyframes chalkWrite{
  0%{opacity:0;transform:translateY(20px);filter:blur(3px)}
  100%{opacity:1;transform:translateY(0);filter:blur(0)}
}

/* ===== Game Academy Cards ===== */
.academy-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(260px,1fr));gap:25px;margin-top:30px}
.academy-card{background:#fff;border-radius:12px;overflow:hidden;box-shadow:0 4px 15px rgba(0,0,0,.1);transition:transform .3s,box-shadow .3s}
.academy-card:hover{transform:translateY(-5px);box-shadow:0 8px 25px rgba(0,0,0,.15)}
.academy-card img{width:100%;height:200px;object-fit:cover}
.academy-card .card-body{padding:20px}
.academy-card h3{color:#1A237E;margin-bottom:8px}
.academy-card p{font-size:.9rem;color:#555;margin-bottom:12px}
.academy-card .btn{display:inline-block;background:#FF6F00;color:#fff;padding:8px 20px;border-radius:6px;font-size:.85rem;transition:background .3s}
.academy-card .btn:hover{background:#E65100;color:#fff}

/* ===== Probability Lab ===== */
.lab-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(280px,1fr));gap:25px;margin-top:30px}
.lab-card{background:linear-gradient(135deg,#1A237E,#283593);border-radius:12px;padding:30px;color:#fff;text-align:center;transition:transform .3s}
.lab-card:hover{transform:scale(1.03)}
.lab-card .lab-icon{font-size:3rem;margin-bottom:15px}
.lab-card h3{color:#fff;margin-bottom:10px}
.lab-card p{color:rgba(255,255,255,.8);font-size:.9rem;margin-bottom:15px}
.lab-card .btn{background:#FF6F00;color:#fff;padding:8px 20px;border-radius:6px;display:inline-block}
.lab-card .btn:hover{background:#E65100;color:#fff}

/* ===== Glossary A-Z ===== */
.glossary-index{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin:30px 0}
.glossary-index a{display:inline-flex;align-items:center;justify-content:center;width:42px;height:42px;background:#1A237E;color:#fff;border-radius:50%;font-weight:700;font-size:.9rem;transition:background .3s}
.glossary-index a:hover{background:#FF6F00;color:#fff}
.daily-word{background:#fff;border-left:4px solid #FF6F00;padding:20px 25px;margin-top:25px;border-radius:0 8px 8px 0;box-shadow:0 2px 8px rgba(0,0,0,.08)}
.daily-word h4{color:#FF6F00;margin-bottom:8px}

/* ===== Roadmap ===== */
.roadmap{position:relative;padding:30px 0}
.roadmap::before{content:"";position:absolute;left:50%;top:0;bottom:0;width:4px;background:#1A237E;transform:translateX(-50%)}
.roadmap-step{position:relative;width:45%;padding:20px;background:#fff;border-radius:12px;box-shadow:0 3px 10px rgba(0,0,0,.08);margin-bottom:30px}
.roadmap-step:nth-child(odd){margin-left:5%}
.roadmap-step:nth-child(even){margin-left:50%}
.roadmap-step::before{content:"";position:absolute;top:25px;width:16px;height:16px;background:#FF6F00;border-radius:50%;border:3px solid #1A237E}
.roadmap-step:nth-child(odd)::before{right:-28px}
.roadmap-step:nth-child(even)::before{left:-28px}
.roadmap-step .step-num{display:inline-block;background:#1A237E;color:#fff;width:30px;height:30px;border-radius:50%;text-align:center;line-height:30px;font-weight:700;font-size:.85rem;margin-bottom:10px}
.roadmap-step h4{color:#1A237E}
.roadmap-step p{font-size:.9rem;color:#555}

@media(max-width:768px){
  .roadmap::before{left:20px}
  .roadmap-step{width:calc(100% - 50px);margin-left:50px!important}
  .roadmap-step::before{left:-38px!important;right:auto!important}
}

/* ===== Timeline / History ===== */
.timeline{position:relative;padding:30px 0}
.timeline::before{content:"";position:absolute;left:50%;top:0;bottom:0;width:3px;background:#283593;transform:translateX(-50%)}
.timeline-item{position:relative;width:45%;padding:20px;background:#fff;border-radius:10px;box-shadow:0 3px 10px rgba(0,0,0,.08);margin-bottom:30px}
.timeline-item:nth-child(odd){margin-left:5%}
.timeline-item:nth-child(even){margin-left:50%}
.timeline-item .year{display:inline-block;background:#FF6F00;color:#fff;padding:4px 14px;border-radius:20px;font-weight:700;font-size:.85rem;margin-bottom:10px}
.timeline-item h4{color:#1A237E}
.timeline-item p{font-size:.9rem;color:#555}

@media(max-width:768px){
  .timeline::before{left:20px}
  .timeline-item{width:calc(100% - 50px);margin-left:50px!important}
}

/* ===== Inner Page Content ===== */
.page-content{background:#fff;padding:40px;border-radius:12px;box-shadow:0 2px 12px rgba(0,0,0,.06);margin:30px 0}
.page-content h1{border-bottom:3px solid #FF6F00;padding-bottom:15px;margin-bottom:25px}
.page-content h2{margin-top:35px;padding-left:15px;border-left:4px solid #FF6F00}
.page-content h3{margin-top:25px;color:#283593}
.page-content img{border-radius:8px;margin:20px 0;box-shadow:0 2px 8px rgba(0,0,0,.1)}
.page-content table{width:100%;border-collapse:collapse;margin:20px 0}
.page-content table th{background:#1A237E;color:#fff;padding:12px 15px;text-align:left;font-size:.9rem}
.page-content table td{padding:10px 15px;border-bottom:1px solid #e0e0e0;font-size:.9rem}
.page-content table tr:hover{background:#f0f0f0}
.page-content blockquote{background:#f8f8ff;border-left:4px solid #1A237E;padding:15px 20px;margin:20px 0;font-style:italic;color:#555}
.page-content .tip-box{background:#FFF3E0;border:1px solid #FF6F00;border-radius:8px;padding:15px 20px;margin:20px 0}
.page-content .tip-box h4{color:#FF6F00;margin-bottom:8px}
.page-content .warning-box{background:#FFEBEE;border:1px solid #C62828;border-radius:8px;padding:15px 20px;margin:20px 0}
.page-content .warning-box h4{color:#C62828;margin-bottom:8px}

/* ===== Calculator UI ===== */
.calc-container{background:#f0f0f5;border-radius:12px;padding:30px;margin:25px 0;border:2px solid #1A237E}
.calc-container h3{text-align:center;color:#1A237E;margin-bottom:20px}
.calc-row{display:flex;gap:15px;margin-bottom:15px;flex-wrap:wrap}
.calc-input{flex:1;min-width:200px}
.calc-input label{display:block;font-size:.85rem;color:#555;margin-bottom:5px;font-weight:600}
.calc-input input,.calc-input select{width:100%;padding:10px 14px;border:2px solid #ccc;border-radius:8px;font-size:.95rem;background:#fff}
.calc-result{background:#1A237E;color:#fff;padding:20px;border-radius:8px;text-align:center;margin-top:20px}
.calc-result .result-num{font-size:2rem;font-weight:700;color:#FF6F00}
.calc-btn{display:inline-block;background:#FF6F00;color:#fff;padding:12px 30px;border:none;border-radius:8px;font-size:1rem;cursor:pointer;margin-top:15px;transition:background .3s}
.calc-btn:hover{background:#E65100}

/* ===== Formula Display ===== */
.formula-box{background:#2d2d2d;color:#e0e0e0;padding:20px;border-radius:8px;margin:20px 0;font-family:"Courier New",monospace;font-size:1.1rem;text-align:center;overflow-x:auto}
.formula-box .var{color:#FF6F00;font-weight:700}

/* ===== Quiz Section ===== */
.quiz-section{background:#f8f8ff;border:2px solid #1A237E;border-radius:12px;padding:25px;margin:30px 0}
.quiz-section h3{color:#1A237E;margin-bottom:15px}
.quiz-item{margin-bottom:20px;padding:15px;background:#fff;border-radius:8px}
.quiz-item p{font-weight:600;margin-bottom:10px}
.quiz-item label{display:block;padding:6px 0;cursor:pointer;font-size:.9rem}
.quiz-item label:hover{color:#FF6F00}

/* ===== Footer ===== */
.site-footer{background:#0D1442;color:#aaa;padding:50px 0 20px}
.footer-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(220px,1fr));gap:30px;margin-bottom:30px}
.footer-col h4{color:#fff;margin-bottom:15px;font-size:1rem;position:relative;padding-bottom:10px}
.footer-col h4::after{content:"";position:absolute;bottom:0;left:0;width:40px;height:3px;background:#FF6F00}
.footer-col a{display:block;color:#aaa;padding:4px 0;font-size:.85rem;transition:color .3s}
.footer-col a:hover{color:#FF6F00}
.footer-col p{font-size:.85rem;line-height:1.6}
.footer-bottom{border-top:1px solid #1a1a4e;padding-top:20px;text-align:center;font-size:.8rem}
.footer-bottom a{color:#aaa}
.responsible-gambling{background:#1a1a4e;border-radius:8px;padding:15px 20px;margin-top:20px;text-align:center;font-size:.8rem;color:#999}
.responsible-gambling strong{color:#FF6F00}

/* ===== Utility ===== */
.text-center{text-align:center}
.mt-20{margin-top:20px}
.mb-20{margin-bottom:20px}
.section-title{text-align:center;margin-bottom:40px}
.section-title h2{display:inline-block;position:relative;padding-bottom:12px}
.section-title h2::after{content:"";position:absolute;bottom:0;left:50%;transform:translateX(-50%);width:60px;height:4px;background:#FF6F00;border-radius:2px}
.section-title p{color:#666;margin-top:10px;font-size:.95rem}
.tag-list{display:flex;flex-wrap:wrap;gap:8px;margin:15px 0}
.tag-list a{display:inline-block;background:#e8eaf6;color:#1A237E;padding:4px 12px;border-radius:20px;font-size:.8rem;transition:background .3s}
.tag-list a:hover{background:#FF6F00;color:#fff}

/* ===== Learning Objectives ===== */
.learning-objectives{background:#E8EAF6;border-radius:12px;padding:25px;margin:25px 0}
.learning-objectives h3{color:#1A237E;margin-bottom:15px}
.learning-objectives ul{padding-left:20px}
.learning-objectives li{padding:5px 0;font-size:.95rem;position:relative;padding-left:25px}
.learning-objectives li::before{content:"✓";position:absolute;left:0;color:#FF6F00;font-weight:700}

/* ===== Error Analysis ===== */
.error-analysis{background:#FFF3E0;border-radius:12px;padding:25px;margin:25px 0;border-left:4px solid #FF6F00}
.error-analysis h3{color:#E65100;margin-bottom:15px}

/* ===== Animations ===== */
.fade-in{opacity:0;transform:translateY(20px);transition:opacity .6s,transform .6s}
.fade-in.visible{opacity:1;transform:translateY(0)}

/* ===== Responsive ===== */
@media(max-width:480px){
  h1{font-size:1.5rem}
  h2{font-size:1.3rem}
  .hero-blackboard{padding:50px 15px}
  .hero-blackboard h1{font-size:1.6rem}
  .page-content{padding:20px}
  .section{padding:40px 0}
  .academy-grid{grid-template-columns:1fr}
  .lab-grid{grid-template-columns:1fr}
}