@import url('https://fonts.googleapis.com/css2?family=Noto+Serif+Bengali:wght@400;600;700&display=swap');:root{--primary:#0d9489;--muted:#6b6b6b;--card-w:420px}*{box-sizing:border-box}body{font-family:'Noto Serif Bengali',serif;margin:0;background:#f4f8f7;color:#17201a;-webkit-font-smoothing:antialiased;-moz-osx-font-smoothing:grayscale}.site-header,.learn-header{background:var(--primary);color:white;padding:1rem}.header-inner{display:flex;justify-content:space-between;align-items:center;gap:1rem;max-width:1100px;margin:0 auto;padding:0 1rem}.brand{margin:0;font-size:1.25rem}.tagline{margin:0;font-size:0.9rem;opacity:0.95}.top-links a{color:rgba(255,255,255,0.95);margin-left:0.8rem;text-decoration:none;font-size:0.95rem}main .topics-wrap{padding:1.25rem}.topics{display:grid;gap:1rem;justify-items:center;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));max-width:1100px;margin:0 auto}.topic-card{width:100%;max-width:300px;background:white;border-radius:12px;box-shadow:0 6px 18px rgba(0,0,0,0.08);padding:1rem;cursor:default;display:flex;flex-direction:column;align-items:flex-start;gap:0.6rem}.topic-card h3{margin:0;font-size:1.05rem}.topic-card p{margin:0;color:var(--muted);font-size:0.9rem}.topic-meta{margin-top:6px;color:#0b6b5c;font-weight:600}.start-btn{margin-top:10px;align-self:stretch;background:var(--primary);color:white;border:none;padding:8px 10px;border-radius:8px;cursor:pointer;font-weight:600}@media (max-width:540px){.topics{grid-template-columns:repeat(2,1fr);gap:0.6rem}.topic-card{max-width:100%}}.topic-card{transition:transform 0.25s ease,box-shadow 0.25s ease}.topic-card:hover{transform:translateY(-6px);box-shadow:0 10px 24px rgba(0,0,0,0.12)}.footer-info{max-width:1100px;margin:1.5rem auto;display:grid;grid-template-columns:1fr 240px 160px;gap:1rem;align-items:start;padding:0 1rem}.bottom-sep{border:0;height:1px;background:rgba(0,0,0,0.06);margin:0 1rem}.site-footer{padding:0.8rem;text-align:center;color:var(--muted);font-size:0.9rem;background:transparent}.learn-header{display:flex;justify-content:space-between;align-items:center;box-sizing:border-box;max-width:1100px;margin:0 auto;padding:0 1rem}.learn-left{display:flex;flex-direction:column;gap:6px}.progress-info{font-size:0.95rem;color:rgba(255,255,255,0.9)}.learn-right{display:flex;gap:8px;align-items:center}.icon-btn{background:rgba(255,255,255,0.12);color:white;border:none;padding:8px 10px;border-radius:8px;cursor:pointer;font-size:0.95rem}.learn-main{padding:1.25rem}.card-area{display:flex;flex-direction:column;align-items:center;gap:1rem}.flashcard{width:var(--card-w);max-width:92vw;height:320px;perspective:1000px;position:relative}.flashcard>div{width:100%;height:100%;border-radius:12px;background:white;box-shadow:0 10px 30px rgba(0,0,0,0.08);position:absolute;backface-visibility:hidden;padding:1.1rem;transition:transform 0.6s;display:flex;flex-direction:column;align-items:center;justify-content:center;text-align:center;gap:0.4rem}.flashcard.flipped .front{transform:rotateY(180deg)}.flashcard.flipped .back{transform:rotateY(0deg)}.front{transform:rotateY(0deg)}.back{transform:rotateY(180deg)}.front h2{margin:0;font-size:2.3rem}.bn-meaning{margin:2px 0;color:var(--muted);font-size:1.1rem}.bn-pron{margin:2px 0 8px 0;color:#2b6b5c;font-size:1.05rem}.speak-btn{align-self:center;margin-top:0.8rem;background:var(--primary);color:white;border:none;padding:8px 12px;border-radius:8px;cursor:pointer}.back .flip-back{width:100%;display:flex;justify-content:flex-end}#flipBackBtn{background:transparent;border:none;font-size:1.25rem;cursor:pointer}.prompt{margin:0;font-weight:600}#spellInput{width:100%;padding:12px;font-size:1.05rem;border-radius:8px;border:1px solid rgba(0,0,0,0.08);margin-top:6px}.validate-full{margin-top:10px;width:100%;padding:10px;background:var(--primary);color:white;border:none;border-radius:8px;cursor:pointer;font-weight:600}.result-msg{margin-top:8px;font-weight:700}.controls{display:flex;gap:8px;justify-content:space-between;width:var(--card-w);max-width:92vw}.control-btn{flex:1;padding:10px;border-radius:8px;border:none;background:#e9f2ef;cursor:pointer}.control-btn.primary{background:var(--primary);color:white}.control-btn.disabled{background:#d3d3d3;pointer-events:none;color:#777}.hidden{display:none}.complete{background:white;padding:14px;border-radius:10px;box-shadow:0 6px 18px rgba(0,0,0,0.06);text-align:center}@media (max-width:880px){.footer-info{grid-template-columns:1fr 1fr;gap:1rem;padding:0 1rem}}@media (max-width:520px){.learn-header{flex-direction:column;align-items:flex-start;gap:8px}.controls{flex-direction:column;align-items:stretch}}.learn-header{background:#006b63;padding:0.6rem 0}.learn-header .header-inner{max-width:1100px;margin:0 auto;padding:0 1rem;display:flex;justify-content:space-between;align-items:center}.learn-header h1{margin:0;font-size:1.6rem}.learn-header .word-count{margin-left:0.8rem;font-size:1rem;color:#e3f6f5}footer{text-align:center;padding:1rem 0;font-size:0.9rem;color:#333}.learn-header{background:var(--primary);color:white;max-width:1100px;margin:0.75rem auto 0 auto;padding:0.5rem 1.2rem;border-radius:10px;display:flex;justify-content:space-between;align-items:center;box-shadow:0 2px 8px rgba(0,0,0,0.08)}.learn-left{display:flex;flex-direction:column;gap:3px}.learn-left h2{margin:0;font-size:1.35rem;line-height:1.2}.progress-info{font-size:0.95rem;color:rgba(255,255,255,0.9)}.learn-right{display:flex;align-items:center;gap:8px}.icon-btn{background:rgba(255,255,255,0.12);color:#fff;border:none;padding:6px 12px;border-radius:6px;cursor:pointer;font-size:0.9rem;font-family:'Noto Serif Bengali',serif;transition:background 0.2s ease}.icon-btn:hover{background:rgba(255,255,255,0.25)}footer.learn-footer{text-align:center;padding:1rem 0;font-size:0.9rem;color:var(--muted);background:transparent}