:root{
  --green:#6aaa64; --darkendGreen:#538d4e; --yellow:#c9b458; --darkendYellow:#b59f3b;
  --color-tone-1:#212121; --color-tone-2:#787c7e; --color-tone-3:#878a8c;
  --color-tone-4:#d3d6da; --color-tone-5:#edeff1; --color-tone-6:#f6f7f8; --color-tone-7:#ffffff;
  --opacity-50:rgba(0,0,0,0.08);
  --color-present:var(--yellow); --color-correct:var(--green); --color-absent:var(--color-tone-2);
  --tile-text-color:#fff;
}

:root[data-theme="dark"]{
  --color-tone-1:#e8e8e6; --color-tone-2:#a8a6a3; --color-tone-3:#8a8886;
  --color-tone-4:#3a3a3c; --color-tone-5:#232325; --color-tone-6:#1c1c1e; --color-tone-7:#131314;
  --opacity-50:rgba(0,0,0,0.35);
  --green:#538d4e; --yellow:#b59f3b;
}

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

/* Fold priority: game is the only thing in view on landing, ads/content
   deferred below so they don't compete visually or for render cost. */
.scroll-cue{
  display:block;text-align:center;font-size:12px;color:var(--ink-faint);
  text-decoration:none;padding:14px 0 6px;
}
.scroll-cue:hover{color:var(--accent);}
.content-section,.two-column,.interactive-quiz{
  content-visibility:auto;
  contain-intrinsic-size:1000px 600px;
}
.content-section{background:var(--color-tone-7);margin:32px auto;max-width:1160px;padding:32px;
  border-radius:12px;border:1px solid var(--color-tone-4);box-shadow:0 2px 10px var(--opacity-50);}
.section-title{font-size:1.7rem;margin:0 0 16px;color:var(--color-tone-1);border-bottom:2px solid var(--green);padding-bottom:8px;}
.section-subtitle{font-size:1.25rem;margin:22px 0 12px;color:var(--color-tone-1);}
.section-content{font-size:1rem;margin-bottom:16px;color:var(--color-tone-2);line-height:1.55;}

.two-column{display:grid;grid-template-columns:2fr 320px;gap:32px;max-width:1160px;margin:32px auto;}
.main-content{background:var(--color-tone-7);padding:32px;border-radius:12px;border:1px solid var(--color-tone-4);box-shadow:0 2px 10px var(--opacity-50);}
.sidebar{display:flex;flex-direction:column;gap:16px;}
.sidebar-widget{background:var(--color-tone-7);padding:18px;border-radius:12px;border:1px solid var(--color-tone-4);box-shadow:0 2px 8px var(--opacity-50);}
.sidebar-widget h3{color:var(--green);margin:0 0 12px;font-size:1.05rem;}

.strategy-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:18px;margin:22px 0;}
.strategy-card{background:var(--color-tone-7);padding:20px;border-radius:12px;border:1px solid var(--color-tone-4);
  transition:transform .2s ease,border-color .2s ease;box-shadow:0 2px 8px var(--opacity-50);}
.strategy-card:hover{transform:translateY(-3px);border-color:var(--green);}
.strategy-card h3{color:var(--green);margin:0 0 10px;font-size:1.1rem;}
.strategy-card p{color:var(--color-tone-2);line-height:1.5;margin:0;font-size:0.92rem;}
.strategy-card .number{background:var(--green);color:#fff;width:28px;height:28px;border-radius:50%;
  display:flex;align-items:center;justify-content:center;font-weight:bold;margin-bottom:10px;}

.stats-container{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:16px;margin:22px 0;}
.stat-card{background:linear-gradient(135deg,var(--green),var(--darkendGreen));color:#fff;padding:20px;
  border-radius:12px;text-align:center;}
.stat-number{font-size:2rem;font-weight:bold;margin-bottom:6px;}
.stat-label{font-size:0.82rem;opacity:0.92;}

.tips-list{list-style:none;margin:20px 0;padding:0;}
.tips-list li{background:var(--color-tone-6);margin:12px 0;padding:16px 16px 16px 24px;border-radius:8px;
  border-left:4px solid var(--yellow);color:var(--color-tone-1);font-size:0.95rem;}
.tips-list li strong{color:var(--darkendYellow);}

.word-examples{display:flex;flex-wrap:wrap;gap:12px;margin:16px 0;justify-content:center;}
.word-example{background:var(--color-tone-5);color:var(--color-tone-1);padding:9px 14px;border-radius:6px;
  font-family:var(--font-mono,monospace);font-weight:bold;border:1px solid var(--color-tone-4);cursor:pointer;
  transition:all .2s ease;}
.word-example:hover{background:var(--green);color:#fff;}

.letter-freq{margin:16px 0;}
.freq-item{display:flex;align-items:center;margin:6px 0;}
.freq-letter{width:26px;font-weight:bold;color:var(--green);}
.freq-bar{flex:1;height:18px;background:var(--color-tone-4);border-radius:9px;margin:0 10px;overflow:hidden;}
.freq-fill{height:100%;background:linear-gradient(90deg,var(--green),var(--darkendGreen));border-radius:9px;transition:width .8s ease;}
.freq-percent{font-size:0.85rem;color:var(--color-tone-2);}

.interactive-quiz{background:var(--color-tone-7);padding:26px;border-radius:12px;border:1px solid var(--color-tone-4);
  max-width:1160px;margin:32px auto;box-shadow:0 2px 10px var(--opacity-50);}
.quiz-question{font-size:1.05rem;margin-bottom:16px;color:var(--color-tone-1);}
.quiz-options{display:grid;gap:8px;margin-bottom:16px;}
.quiz-option{background:var(--color-tone-5);padding:13px;border-radius:8px;cursor:pointer;transition:all .2s ease;
  border:2px solid transparent;color:var(--color-tone-1);font-size:0.95rem;}
.quiz-option:hover{background:var(--color-tone-4);border-color:var(--green);}
.quiz-option.correct{background:var(--green);color:#fff;border-color:var(--darkendGreen);}
.quiz-option.incorrect{background:#e24b4a;color:#fff;border-color:#c23c3b;}

.footer{background:var(--color-tone-6);color:var(--color-tone-2);padding:32px 0;border-top:1px solid var(--color-tone-4);margin-top:40px;}
.footer-content{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:28px;max-width:1160px;margin:0 auto;padding:0 20px;}
.footer h4{margin:0 0 10px;color:var(--green);font-size:0.95rem;}
.footer ul{list-style:none;margin:0;padding:0;}
.footer ul li{margin-bottom:6px;}
.footer a{color:var(--color-tone-2);text-decoration:none;font-size:0.88rem;}
.footer button{color:var(--color-tone-2);text-decoration:none;font-size:0.88rem;
  background:none;border:none;padding:0;font-family:inherit;cursor:pointer;text-align:left;}
.footer a:hover,.footer button:hover{color:var(--green);}
.footer a:hover{color:var(--green);}
.footer-bottom{text-align:center;margin-top:22px;padding-top:22px;border-top:1px solid var(--color-tone-4);
  max-width:1160px;margin-left:auto;margin-right:auto;padding-left:20px;padding-right:20px;font-size:0.82rem;}

.fade-in{opacity:0;transform:translateY(20px);transition:all .5s ease;}
.fade-in.visible{opacity:1;transform:translateY(0);}

/* Solver tool */
.solver-container{display:grid;grid-template-columns:1fr 1fr;gap:28px;margin:20px 0;}
.solver-section-title{color:var(--green);font-size:1.15rem;margin-bottom:14px;}
.solver-instructions{background:var(--color-tone-6);padding:10px 14px;border-radius:8px;font-size:0.85rem;
  color:var(--color-tone-2);margin-bottom:16px;border-left:3px solid var(--yellow);}
.solver-board{display:flex;flex-direction:column;gap:6px;margin-bottom:20px;}
.solver-row{display:flex;gap:6px;justify-content:center;}
.solver-tile{width:48px;height:48px;border:2px solid var(--color-tone-4);border-radius:4px;cursor:pointer;
  transition:all .2s ease;display:flex;align-items:center;justify-content:center;background:var(--color-tone-7);}
.solver-tile:hover{border-color:var(--color-tone-3);transform:scale(1.04);}
.solver-input{width:100%;height:100%;border:none;background:transparent;text-align:center;font-size:1.4rem;
  font-weight:bold;color:var(--color-tone-1);text-transform:uppercase;outline:none;}
.solver-tile[data-state="absent"]{background:var(--color-tone-2);border-color:var(--color-tone-2);}
.solver-tile[data-state="absent"] .solver-input{color:#fff;}
.solver-tile[data-state="present"]{background:var(--color-present);border-color:var(--color-present);}
.solver-tile[data-state="present"] .solver-input{color:#fff;}
.solver-tile[data-state="correct"]{background:var(--color-correct);border-color:var(--color-correct);}
.solver-tile[data-state="correct"] .solver-input{color:#fff;}
.solver-controls{display:flex;gap:10px;flex-wrap:wrap;justify-content:center;}
.solver-btn{padding:10px 16px;border:none;border-radius:8px;font-size:0.9rem;font-weight:600;cursor:pointer;transition:all .2s ease;}
.solver-btn-primary{background:linear-gradient(135deg,var(--green),var(--darkendGreen));color:#fff;}
.solver-btn-primary:hover{transform:translateY(-1px);}
.solver-btn-secondary{background:var(--color-tone-4);color:var(--color-tone-1);}
.solver-btn-hint{background:linear-gradient(135deg,var(--yellow),var(--darkendYellow));color:#fff;}
.solver-results-section{background:var(--color-tone-6);padding:20px;border-radius:12px;border:1px solid var(--color-tone-4);}
.results-empty{text-align:center;padding:30px 16px;color:var(--color-tone-2);}
.empty-icon{font-size:2.4rem;margin-bottom:10px;}
.example-hint{background:var(--color-tone-7);padding:12px;border-radius:8px;border-left:3px solid var(--green);
  margin-top:16px;font-size:0.85rem;text-align:left;}
.word-suggestions{display:grid;gap:10px;}
.suggestion-item{background:var(--color-tone-7);padding:12px;border-radius:8px;border:1px solid var(--color-tone-4);
  display:flex;justify-content:space-between;align-items:center;}
.suggestion-word{font-family:var(--font-mono,monospace);font-size:1.2rem;font-weight:bold;color:var(--green);letter-spacing:0.15rem;}
.suggestion-info{text-align:right;font-size:0.85rem;color:var(--color-tone-2);}
.analytics-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(160px,1fr));gap:14px;margin-top:16px;}
.analytics-card{background:linear-gradient(135deg,var(--green),var(--darkendGreen));color:#fff;padding:18px;border-radius:12px;text-align:center;}
.analytics-number{font-size:1.9rem;font-weight:bold;margin-bottom:6px;}
.analytics-label{font-size:0.82rem;opacity:0.92;}

/* FAQ accordion */
.faq-container{margin-top:20px;}
.faq-category{margin-bottom:24px;border:1px solid var(--color-tone-4);border-radius:12px;overflow:hidden;
  background:var(--color-tone-7);box-shadow:0 2px 8px var(--opacity-50);}
.faq-category-title{background:linear-gradient(135deg,var(--green),var(--darkendGreen));color:#fff;margin:0;
  padding:14px 18px;font-size:1.05rem;font-weight:600;}
.faq-item{border-bottom:1px solid var(--color-tone-4);}
.faq-item:last-child{border-bottom:none;}
.faq-question{width:100%;background:none;border:none;padding:14px 18px;text-align:left;cursor:pointer;
  font-size:0.95rem;font-weight:500;color:var(--color-tone-1);display:flex;justify-content:space-between;
  align-items:center;transition:all .2s ease;}
.faq-question:hover{background:var(--color-tone-6);color:var(--green);}
.faq-question[aria-expanded="true"]{background:var(--color-tone-6);color:var(--green);}
.faq-icon{font-size:1.3rem;font-weight:bold;color:var(--green);transition:transform .2s ease;margin-left:12px;flex-shrink:0;}
.faq-question[aria-expanded="true"] .faq-icon{transform:rotate(45deg);}
.faq-answer{max-height:0;overflow:hidden;transition:max-height .3s ease;}
.faq-answer.active{max-height:1000px;}
.faq-content{padding:0 18px 18px;color:var(--color-tone-2);line-height:1.55;font-size:0.9rem;}
.faq-content ul{margin:10px 0;padding-left:18px;}
.faq-content li{margin-bottom:6px;}
.faq-content strong{color:var(--green);}

@media (max-width:768px){
  .two-column{grid-template-columns:1fr;}
  .sidebar{order:-1;}
  .solver-container{grid-template-columns:1fr;}
  .content-section,.main-content{padding:20px;}
  .footer-content{grid-template-columns:repeat(2,1fr);}
}
@media (max-width:480px){
  .stats-container{grid-template-columns:1fr;}
  .footer-content{grid-template-columns:1fr;}
  .solver-tile{width:42px;height:42px;}
  .solver-input{font-size:1.2rem;}
}