:root{
  --bg:#07101f;--bg2:#030812;--panel:#111c31;--panel2:#172640;--panel3:#0d1729;
  --text:#f7f9ff;--muted:#9ba9c2;--line:#263651;--blue:#48a7ff;--purple:#914cff;
  --green:#38d6a0;--orange:#ffb454;--red:#ff6b78;--shadow:0 16px 44px rgba(0,0,0,.28);
  --radius:22px;
}
*{box-sizing:border-box}html,body{margin:0;min-height:100%;background:var(--bg2);color:var(--text);font-family:Inter,ui-sans-serif,system-ui,-apple-system,"Segoe UI",Arial,sans-serif}
button,input,textarea,select{font:inherit}.app-shell{width:min(100%,520px);min-height:100vh;margin:auto;background:radial-gradient(circle at 84% -5%,#1b3268 0,transparent 33%),var(--bg);padding-bottom:92px;position:relative}
.topbar{position:sticky;top:0;z-index:30;display:flex;align-items:center;gap:12px;padding:18px 16px 12px;background:linear-gradient(to bottom,rgba(7,16,31,.98),rgba(7,16,31,.86),transparent);backdrop-filter:blur(12px)}
.brand{font-size:24px;font-weight:950;letter-spacing:.4px}.brand span{background:linear-gradient(90deg,var(--blue),var(--purple));-webkit-background-clip:text;color:transparent}.small{font-size:12px}.muted{color:var(--muted)}
.avatar,.icon-btn{border:1px solid #31425f;background:#1b2942;color:var(--text);width:42px;height:42px;border-radius:50%;display:grid;place-items:center}.avatar{margin-left:auto}.hidden{display:none!important}
main{padding:6px 16px 26px}.card{background:linear-gradient(145deg,rgba(25,39,66,.97),rgba(13,24,43,.98));border:1px solid rgba(100,129,180,.22);border-radius:var(--radius);box-shadow:var(--shadow);padding:18px;margin:12px 0}.hero{background:radial-gradient(circle at 90% 10%,rgba(132,72,255,.35),transparent 37%),linear-gradient(145deg,#14284d,#111a35)}
.eyebrow{font-size:11px;color:#aebbd0;font-weight:900;letter-spacing:.85px;text-transform:uppercase}.title{font-size:28px;line-height:1.08;margin:8px 0}.subtitle{font-size:14px;color:#c3cee0;line-height:1.55}.row{display:flex;gap:10px;align-items:center}.between{justify-content:space-between}.wrap{flex-wrap:wrap}
.btn{border:0;border-radius:15px;padding:13px 15px;font-weight:800;cursor:pointer;color:white;background:#223452}.btn.primary{background:linear-gradient(90deg,#38bdf8,#7c4dff,#bd36f0);box-shadow:0 10px 26px rgba(100,75,255,.25)}.btn.ghost{background:#15233a;border:1px solid #344a6c}.btn.success{background:#17765b}.btn.danger{background:#823744}.btn.smallbtn{padding:9px 11px;font-size:12px}.btn.block{width:100%}.btn:disabled{opacity:.45;cursor:not-allowed}
.stats{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-top:16px}.stat{text-align:center;padding:11px 6px;background:rgba(10,20,38,.45);border-radius:14px;border:1px solid rgba(90,118,163,.16)}.stat b{display:block;font-size:17px}.stat small{color:var(--muted)}
.bar{height:9px;background:#293854;border-radius:99px;overflow:hidden;margin-top:12px}.fill{height:100%;background:linear-gradient(90deg,var(--blue),var(--purple));border-radius:99px;transition:.35s}.section-head{display:flex;justify-content:space-between;align-items:end;margin:22px 2px 8px}.section-head h3{margin:0;font-size:19px}.section-head span{font-size:12px;color:var(--muted)}
.grid2{display:grid;grid-template-columns:repeat(2,1fr);gap:10px}.grid3{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}.tile{padding:16px;border-radius:18px;background:linear-gradient(145deg,#152640,#0e1b31);border:1px solid #2b3d5c;cursor:pointer}.tile h4{margin:8px 0 4px}.tile p{margin:0;color:var(--muted);font-size:12px;line-height:1.45}.tile .icon{font-size:24px}.tile.locked{opacity:.58}.domain{border-left:4px solid var(--blue)}
.skill-list{display:grid;gap:9px}.skill-item{display:flex;gap:12px;align-items:center;padding:14px;border-radius:16px;background:#111d32;border:1px solid #263958;cursor:pointer}.skill-num{width:34px;height:34px;border-radius:11px;background:#213755;display:grid;place-items:center;font-weight:900}.skill-body{flex:1}.skill-body b{display:block}.skill-body small{color:var(--muted)}.score-pill{font-size:11px;padding:6px 8px;border-radius:999px;background:#20324e;color:#c9d7ec}
.chips{display:flex;gap:7px;flex-wrap:wrap;margin:10px 0}.chip{padding:7px 9px;border-radius:999px;background:#1b2a45;border:1px solid #314661;color:#dbe6f7;font-size:11px}.chip.clickable{cursor:pointer}.chip.good{background:#124a3b;border-color:#1d7e62}.chip.bad{background:#542c36;border-color:#82414d}
.lesson-block{margin:15px 0;padding:15px;border-radius:16px;background:#0e192b;border:1px solid #263651}.lesson-block h3,.lesson-block h4{margin:0 0 8px}.lesson-block p,.lesson-block li{color:#d3dced;line-height:1.62}.lesson-block ul,.lesson-block ol{padding-left:20px}.formula{font-family:"Cambria Math","Times New Roman",serif;font-size:18px;background:#0a1323;padding:12px;border-radius:12px;border:1px dashed #365071;overflow:auto}.example{border-left:3px solid var(--green)}
.question-card{padding:18px;border-radius:20px;background:#111e34;border:1px solid #2a3c5b}.qmeta{display:flex;justify-content:space-between;color:var(--muted);font-size:11px;margin-bottom:10px}.question{font-size:18px;font-weight:800;line-height:1.45;margin:8px 0 14px}.options{display:grid;gap:9px}.option{border:1px solid #344864;background:#17263e;color:var(--text);text-align:left;padding:12px 13px;border-radius:14px;cursor:pointer}.option.correct{background:#124a3b;border-color:#2da77f}.option.wrong{background:#592d37;border-color:#bb5262}.explanation{margin-top:12px;padding:12px;border-radius:13px;background:#0d1728;color:#dbe5f5;line-height:1.55;border:1px solid #263651}
.progress-dots{display:flex;gap:4px;flex-wrap:wrap}.dot{width:7px;height:7px;border-radius:50%;background:#2c3e59}.dot.done{background:var(--green)}.dot.current{background:var(--blue)}
.input,.textarea,.select{width:100%;border:1px solid #334a6a;background:#0d182a;color:var(--text);border-radius:14px;padding:12px;outline:none}.textarea{min-height:120px;resize:vertical}.field{margin:12px 0}.field label{display:block;font-size:12px;color:#b7c5da;margin-bottom:6px}.search{position:sticky;top:76px;z-index:15;background:rgba(7,16,31,.94);padding:8px 0;backdrop-filter:blur(8px)}
.table{width:100%;border-collapse:collapse;font-size:13px}.table th,.table td{padding:9px 8px;border-bottom:1px solid #263651;text-align:left}.table th{color:#aec1da}.term{font-weight:800}.pron{color:#9fb2cc;font-size:11px}.empty{text-align:center;color:var(--muted);padding:30px 12px}
.result-row{display:grid;grid-template-columns:1fr auto;gap:8px;padding:12px 0;border-bottom:1px solid #263651}.result-row:last-child{border:0}.score{font-weight:900}.score.good{color:var(--green)}.score.mid{color:var(--orange)}.score.bad{color:var(--red)}
.chat{display:grid;gap:10px;max-height:58vh;overflow:auto;padding-right:2px}.bubble{max-width:88%;padding:12px 14px;border-radius:17px;line-height:1.55;font-size:14px}.bubble.user{justify-self:end;background:#254b78}.bubble.ai{justify-self:start;background:#14233c;border:1px solid #2e4567}.chatbox{position:sticky;bottom:82px;background:linear-gradient(to top,var(--bg) 72%,transparent);padding-top:16px}.chat-input-row{display:flex;gap:8px}.chat-input-row input{flex:1}
.bottom-nav{position:fixed;z-index:40;bottom:0;left:50%;transform:translateX(-50%);width:min(100%,520px);height:76px;padding-bottom:env(safe-area-inset-bottom);display:flex;justify-content:space-around;align-items:center;background:rgba(7,16,31,.96);backdrop-filter:blur(18px);border-top:1px solid #24334c}.nav-item{border:0;background:none;color:#8e9bb2;font-size:10px;min-width:62px}.nav-item b{display:block;font-size:20px;margin-bottom:3px}.nav-item.active{color:#61adff}
.modal-backdrop{position:fixed;z-index:80;inset:0;background:rgba(0,0,0,.62);display:grid;place-items:end center}.modal{width:min(100%,520px);max-height:88vh;overflow:auto;background:#0d1728;border-radius:24px 24px 0 0;padding:20px;border:1px solid #2b3e5d}.modal h2{margin-top:0}.toast{position:fixed;z-index:100;left:50%;bottom:88px;transform:translateX(-50%) translateY(20px);opacity:0;background:#edf4ff;color:#10203a;padding:10px 15px;border-radius:12px;font-size:12px;transition:.25s;max-width:88%;text-align:center}.toast.show{opacity:1;transform:translateX(-50%) translateY(0)}
.badge{display:inline-flex;gap:5px;align-items:center;padding:6px 9px;border-radius:999px;background:#1b2b46;font-size:11px}.badge.green{background:#124a3b}.badge.orange{background:#543f20}.warning{padding:12px;border-radius:14px;background:#3d3020;border:1px solid #70542d;color:#ffe5b9;line-height:1.5}.successbox{padding:12px;border-radius:14px;background:#123b31;border:1px solid #236d58;color:#d7fff2;line-height:1.5}
@media(max-width:390px){.grid2{grid-template-columns:1fr}.title{font-size:25px}.stats{grid-template-columns:repeat(3,1fr)}.topbar{padding-left:12px;padding-right:12px}main{padding-left:12px;padding-right:12px}}