:root{--yellow:#fc0;--black:#111;--gray:#6b6b6b;--light:#f4f4f4;--white:#fff;--radius:16px}*{box-sizing:border-box}body,html{margin:0;padding:0;font-family:system-ui,-apple-system,Segoe UI,Roboto,sans-serif;background:var(--light);color:var(--black)}.app{max-width:480px;margin:0 auto;min-height:100vh;background:var(--white);display:flex;flex-direction:column}.topbar{background:var(--black);color:var(--white);padding:18px 20px;display:flex;align-items:center;justify-content:space-between;position:-webkit-sticky;position:sticky;top:0;z-index:60}.brand{font-weight:900;letter-spacing:1px;font-size:20px}.brand .fin{color:var(--yellow)}.content{flex:1 1;padding:20px}.hero{background:var(--yellow);border-radius:var(--radius);padding:20px;margin-bottom:16px}.hero h2{margin:0 0 12px;font-weight:900}.progress{background:rgba(0,0,0,.15);border-radius:999px;height:22px;overflow:hidden}.progress>div{background:var(--black);color:var(--yellow);height:100%;display:flex;align-items:center;justify-content:center;font-size:13px;font-weight:800;transition:width .4s ease}.stats{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:10px;gap:10px;margin-bottom:16px}.stat{background:var(--light);border-radius:12px;padding:12px;text-align:center}.stat .value{font-size:22px;font-weight:900}.stat .label{font-size:11px;color:var(--gray);text-transform:uppercase}.card{background:var(--white);border:2px solid var(--black);border-radius:var(--radius);padding:18px;margin-bottom:16px}.card h3{margin:0 0 10px}button{font-family:inherit;cursor:pointer;border:none;border-radius:12px;padding:12px 16px;font-weight:800;font-size:15px}.btn-primary{background:var(--black);color:var(--yellow);width:100%}.btn-yellow{background:var(--yellow);color:var(--black)}.btn-ghost{background:transparent;color:var(--black);text-decoration:underline;padding:6px}.option{display:block;width:100%;text-align:left;background:var(--light);margin-bottom:8px;border:2px solid transparent}.option.correct{border-color:#2e7d32;background:#e8f5e9}.option.wrong{border-color:#c62828;background:#ffebee}input,select,textarea{width:100%;padding:12px;border:2px solid #ddd;border-radius:12px;font-size:15px;font-family:inherit;margin-bottom:10px}.tiles{display:grid;grid-template-columns:1fr 1fr;grid-gap:12px;gap:12px;margin-top:4px}.tile{background:var(--black);color:var(--white);border-radius:var(--radius);padding:18px 14px;text-align:left;cursor:pointer;border:none;min-height:96px;display:flex;flex-direction:column;justify-content:space-between}.tile.accent{background:var(--yellow);color:var(--black)}.tile .tile-icon{font-size:26px}.tile .tile-title{font-weight:900;font-size:15px}.tile .tile-sub{font-size:12px;opacity:.75}.level-bar{background:rgba(0,0,0,.12);border-radius:999px;height:10px;overflow:hidden;margin:8px 0 4px}.level-bar>div{background:var(--black);height:100%;transition:width .4s ease}.level-row{display:flex;justify-content:space-between;align-items:center;padding:10px 0;border-bottom:1px solid #eee}.level-row.current{background:var(--yellow);border-radius:12px;padding:10px 12px;border:none}.level-badge{display:inline-flex;align-items:center;justify-content:center;width:34px;height:34px;border-radius:50%;background:var(--black);color:var(--yellow);font-weight:900;flex-shrink:0}.back-btn{background:transparent;color:var(--white);border:none;font-size:15px;padding:0;cursor:pointer}.statusbar{position:fixed;bottom:0;left:50%;transform:translateX(-50%);width:100%;max-width:480px;background:var(--black);color:var(--white);display:flex;justify-content:space-around;padding:10px 0;border-top:3px solid var(--yellow);z-index:50}.statusbar>div{text-align:center}.statusbar b{display:block;font-size:18px}.statusbar span{font-size:11px;opacity:.75;text-transform:uppercase}.modal-overlay{position:fixed;inset:0;background:rgba(0,0,0,.5);display:flex;align-items:flex-end;justify-content:center;z-index:100}.modal{background:var(--white);width:100%;max-width:480px;border-radius:20px 20px 0 0;padding:20px}.timer{font-weight:900;font-size:18px}.timer.low{color:#c62828}.tabbar{display:flex;border-top:1px solid #eee;position:-webkit-sticky;position:sticky;bottom:0;background:var(--white)}.tabbar button{flex:1 1;background:transparent;border-radius:0;padding:14px 4px;font-size:12px;color:var(--gray)}.tabbar button.active{color:var(--black);border-top:3px solid var(--yellow)}.chips{display:flex;flex-wrap:wrap;gap:8px;margin-bottom:10px}.chip{background:var(--light);border:2px solid transparent;border-radius:999px;padding:8px 14px;font-size:14px;font-weight:700}.chip.on{background:var(--yellow);border-color:var(--black)}.error{color:#c62828;margin:8px 0}.error,.muted{font-size:14px}.muted{color:var(--gray)}.chat-msg{padding:10px 14px;border-radius:14px;margin-bottom:8px;max-width:85%}.chat-msg.user{background:var(--yellow);margin-left:auto}.chat-msg.assistant{background:var(--light)}