:root{
  --bg:#0a0c16; --bg2:#11142a; --card:rgba(255,255,255,.045); --card2:rgba(255,255,255,.08);
  --line:rgba(255,255,255,.10); --line2:rgba(255,255,255,.18);
  --tx:#eef0ff; --tx2:#b7bbd6; --tx3:#7d82a6;
  --ok:#22d39a; --bad:#ff5d73; --warn:#ffd166;
  --accent:#8b7bff; --accent2:#5ad1ff; --glow:rgba(139,123,255,.35);
  --r:18px; --r2:12px;
  --shadow:0 20px 60px -20px rgba(0,0,0,.6);
  --mono:'JetBrains Mono',ui-monospace,monospace;
}
body.s-shqip{--accent:#ff4d5e;--accent2:#ffb35c;--glow:rgba(255,77,94,.35)}
body.s-kimi{--accent:#16e0a3;--accent2:#5ad1ff;--glow:rgba(22,224,163,.30)}
body.s-fizike{--accent:#5a8bff;--accent2:#c77dff;--glow:rgba(90,139,255,.35)}

*{box-sizing:border-box}
html{scroll-behavior:smooth}
body{margin:0;background:var(--bg);color:var(--tx);font:16px/1.6 Inter,system-ui,sans-serif;min-height:100vh;overflow-x:hidden}
h1,h2,h3,h4{font-family:Sora,Inter,sans-serif;line-height:1.2;margin:0 0 .5em}
a{color:var(--accent2)}
b,strong{color:#fff}
.mono{font-family:var(--mono)}
sub,sup{font-size:.7em}

.bg-orbs{position:fixed;inset:0;z-index:-1;overflow:hidden;pointer-events:none}
.bg-orbs span{position:absolute;width:55vmax;height:55vmax;border-radius:50%;filter:blur(90px);opacity:.22;animation:float 22s ease-in-out infinite}
.bg-orbs span:nth-child(1){background:var(--accent);left:-20vmax;top:-20vmax}
.bg-orbs span:nth-child(2){background:var(--accent2);right:-25vmax;top:20vh;animation-delay:-7s}
.bg-orbs span:nth-child(3){background:#3a2bff;left:20vw;bottom:-35vmax;animation-delay:-14s;opacity:.15}
@keyframes float{50%{transform:translate(6vmax,4vmax) scale(1.1)}}

/* top bar */
.topbar{position:sticky;top:0;z-index:50;display:flex;align-items:center;gap:16px;padding:12px clamp(16px,4vw,40px);background:rgba(10,12,22,.72);backdrop-filter:blur(14px);border-bottom:1px solid var(--line)}
.brand{font-family:Sora;font-weight:700;font-size:20px;color:var(--tx);text-decoration:none;display:flex;align-items:center;gap:8px;white-space:nowrap}
.brand b{background:linear-gradient(90deg,var(--accent),var(--accent2));-webkit-background-clip:text;background-clip:text;color:transparent}
.brand-dot{width:12px;height:12px;border-radius:50%;background:linear-gradient(135deg,var(--accent),var(--accent2));box-shadow:0 0 14px var(--glow)}
.subjects{display:flex;gap:6px;margin-left:auto;overflow-x:auto}
.subjects a{color:var(--tx2);text-decoration:none;padding:8px 14px;border-radius:999px;font-weight:600;font-size:14px;border:1px solid transparent;white-space:nowrap;transition:.2s}
.subjects a:hover{color:#fff;background:var(--card2)}
.subjects a.on{color:#fff;background:linear-gradient(135deg,var(--accent),var(--accent2));box-shadow:0 6px 24px -6px var(--glow)}
.score-pill{padding:6px 12px;border-radius:999px;background:var(--card2);border:1px solid var(--line);font-size:14px;white-space:nowrap}
@media(max-width:640px){.brand{font-size:0}.brand-dot{width:18px;height:18px}.subjects a{padding:7px 10px;font-size:13px}.score-pill{font-size:12px;padding:5px 9px}}

main{max-width:1200px;margin:0 auto;padding:24px clamp(16px,4vw,40px) 60px}
.foot{text-align:center;color:var(--tx3);font-size:13px;padding:30px 16px 50px}

/* home */
.hero{text-align:center;padding:40px 0 20px}
.hero h1{font-size:clamp(34px,6vw,64px);font-weight:800;letter-spacing:-.02em}
.hero h1 span{background:linear-gradient(90deg,#ff4d5e,#ffd166,#16e0a3,#5a8bff,#c77dff);-webkit-background-clip:text;background-clip:text;color:transparent}
.hero p{color:var(--tx2);max-width:640px;margin:0 auto;font-size:18px}
.order{display:inline-flex;gap:8px;align-items:center;margin-top:18px;padding:8px 16px;border-radius:999px;background:var(--card);border:1px solid var(--line);color:var(--tx2);font-size:14px}
.subject-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(280px,1fr));gap:22px;margin-top:36px;perspective:1200px}
.subj-card{position:relative;display:block;text-decoration:none;color:var(--tx);border-radius:24px;padding:26px;min-height:300px;background:linear-gradient(160deg,rgba(255,255,255,.08),rgba(255,255,255,.02));border:1px solid var(--line2);overflow:hidden;transform-style:preserve-3d;transition:transform .25s ease, box-shadow .25s}
.subj-card:hover{box-shadow:0 30px 70px -25px var(--c)}
.subj-card .num{position:absolute;top:18px;right:22px;font:800 64px Sora;color:rgba(255,255,255,.06)}
.subj-card .ico{font-size:46px;transform:translateZ(40px);display:inline-block}
.subj-card h2{font-size:26px;margin-top:10px;transform:translateZ(30px)}
.subj-card p{color:var(--tx2);font-size:14px;margin:0 0 14px}
.subj-card ul{margin:0;padding:0;list-style:none;display:flex;flex-wrap:wrap;gap:6px}
.subj-card li{font-size:12px;padding:4px 10px;border-radius:999px;background:rgba(255,255,255,.07);color:var(--tx2)}
.subj-card .bar{margin-top:18px;height:6px;border-radius:9px;background:rgba(255,255,255,.08);overflow:hidden}
.subj-card .bar i{display:block;height:100%;background:var(--c);border-radius:9px;width:0;transition:width .6s}
.subj-card .glowball{position:absolute;width:220px;height:220px;border-radius:50%;background:var(--c);filter:blur(70px);opacity:.35;right:-60px;bottom:-80px}
.how{display:grid;grid-template-columns:repeat(auto-fit,minmax(200px,1fr));gap:14px;margin-top:40px}
.how div{background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:16px}
.how b{display:block;font-family:Sora;margin-bottom:4px}
.how span{color:var(--tx2);font-size:14px}

/* subject page */
.subj-head{display:flex;align-items:flex-end;justify-content:space-between;gap:16px;flex-wrap:wrap;margin:10px 0 18px}
.subj-head h1{font-size:clamp(28px,4.5vw,44px);margin:0}
.subj-head h1 small{display:block;font:600 14px Inter;color:var(--accent);letter-spacing:.12em;text-transform:uppercase;margin-bottom:6px}
.subj-head p{margin:6px 0 0;color:var(--tx2)}
.tabs{position:sticky;top:61px;z-index:40;display:flex;gap:6px;padding:6px;border-radius:16px;background:rgba(17,20,42,.85);backdrop-filter:blur(12px);border:1px solid var(--line);overflow-x:auto;margin-bottom:24px;scrollbar-width:none}
.tabs::-webkit-scrollbar{display:none}
.tabs button{flex:1 0 auto;background:none;border:0;color:var(--tx2);font:600 14px Inter;padding:10px 14px;border-radius:11px;cursor:pointer;white-space:nowrap;transition:.2s}
.tabs button:hover{color:#fff;background:var(--card2)}
.tabs button.on{color:#0a0c16;background:linear-gradient(135deg,var(--accent),var(--accent2))}
.tabs button .n{display:inline-block;min-width:18px;font-size:11px;opacity:.7;margin-left:4px}

/* lesson nav */
.layout{display:grid;grid-template-columns:240px minmax(0,1fr);gap:26px;align-items:start}
.layout>*,.lessons,.lesson,.viz,.grid2>*,.grid3>*{min-width:0}
@media(max-width:900px){.layout{grid-template-columns:1fr}.toc{position:static!important;display:flex;overflow-x:auto;gap:6px}.toc a{white-space:nowrap}}
.toc{position:sticky;top:130px;display:flex;flex-direction:column;gap:4px;background:var(--card);border:1px solid var(--line);border-radius:var(--r);padding:10px}
.toc a{color:var(--tx2);text-decoration:none;font-size:13.5px;padding:8px 10px;border-radius:9px;line-height:1.35}
.toc a:hover,.toc a.on{background:var(--card2);color:#fff}
.toc a .k{color:var(--accent);font-weight:700;margin-right:6px}

.lesson{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:clamp(18px,3vw,32px);margin-bottom:26px;scroll-margin-top:130px}
.lesson>h2{font-size:clamp(22px,3vw,30px);display:flex;gap:12px;align-items:center}
.lesson>h2 .tag{font:700 12px Inter;padding:4px 10px;border-radius:999px;background:var(--accent);color:#0a0c16;letter-spacing:.04em}
.lesson h3{font-size:19px;margin-top:26px;color:#fff}
.lesson h3::before{content:"";display:inline-block;width:10px;height:10px;border-radius:3px;background:var(--accent);margin-right:10px;transform:rotate(45deg) translateY(-2px)}
.lesson p,.lesson li{color:var(--tx2)}
.lesson ul,.lesson ol{padding-left:22px}
.lesson li{margin:4px 0}
.goal{display:flex;gap:12px;align-items:flex-start;background:linear-gradient(135deg,rgba(255,255,255,.07),rgba(255,255,255,.02));border-left:4px solid var(--accent);border-radius:12px;padding:14px 16px;margin:14px 0}
.goal .gi{font-size:22px}
.key{background:rgba(255,209,102,.09);border:1px solid rgba(255,209,102,.35);border-radius:14px;padding:14px 18px;margin:16px 0;color:#ffe9b0}
.key b{color:#ffd166}
.key::before{content:"🔑 MBAJ MEND";display:block;font:700 11px Inter;letter-spacing:.12em;color:#ffd166;margin-bottom:6px}
.trick{background:rgba(90,209,255,.08);border:1px dashed rgba(90,209,255,.45);border-radius:14px;padding:12px 16px;margin:14px 0;color:#cdeeff}
.trick::before{content:"🧠 TRUK PËR KUJTESË";display:block;font:700 11px Inter;letter-spacing:.12em;color:#5ad1ff;margin-bottom:4px}
.law{font-family:Sora;font-weight:600;font-size:17px;color:#fff;background:linear-gradient(90deg,var(--glow),transparent);border-left:4px solid var(--accent);padding:12px 16px;border-radius:10px;margin:12px 0}
.formula{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:10px 22px;font-family:var(--mono);font-size:clamp(17px,2.4vw,22px);color:#fff;background:#0d1024;border:1px solid var(--line2);border-radius:14px;padding:16px;margin:14px 0;text-align:center}
.formula .lbl{font:600 12px Inter;color:var(--tx3);display:block}
.frac{display:inline-flex;flex-direction:column;align-items:center;vertical-align:middle;margin:0 2px}
.frac>span:first-child{border-bottom:2px solid currentColor;padding:0 4px}
.frac>span{line-height:1.25}
.grid2{display:grid;grid-template-columns:repeat(auto-fit,minmax(240px,1fr));gap:14px;margin:14px 0}
.grid3{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:12px;margin:14px 0}
.mini{background:rgba(255,255,255,.04);border:1px solid var(--line);border-radius:14px;padding:14px}
.mini h4{font-size:15px;margin-bottom:6px;color:#fff}
.mini p{margin:0;font-size:14px}
.chip{display:inline-block;font-size:12px;font-weight:600;padding:3px 9px;border-radius:999px;background:var(--card2);color:var(--tx);margin:2px}
.chip.g{background:rgba(255,77,94,.18);color:#ff9aa5}
.chip.t{background:rgba(90,139,255,.2);color:#a9c2ff}
table.tbl{width:100%;border-collapse:separate;border-spacing:0;margin:14px 0;font-size:14px;overflow:hidden;border-radius:12px;border:1px solid var(--line)}
.tbl th{background:rgba(255,255,255,.07);color:#fff;text-align:left;padding:10px 12px;font-family:Sora;font-size:13px}
.tbl td{padding:9px 12px;border-top:1px solid var(--line);color:var(--tx2);vertical-align:top}
.tbl tr:hover td{background:rgba(255,255,255,.03)}
.tblwrap{overflow-x:auto}
.check-inline{margin-top:18px;border-top:1px dashed var(--line2);padding-top:14px}
.check-inline>b{font-family:Sora;display:block;margin-bottom:8px}

/* buttons */
.btn{display:inline-flex;align-items:center;gap:8px;border:1px solid var(--line2);background:var(--card2);color:var(--tx);font:600 14px Inter;padding:10px 16px;border-radius:12px;cursor:pointer;transition:.15s;text-decoration:none}
.btn:hover{background:rgba(255,255,255,.14);transform:translateY(-1px)}
.btn.primary{background:linear-gradient(135deg,var(--accent),var(--accent2));color:#0a0c16;border:0}
.btn.small{padding:6px 11px;font-size:13px;border-radius:9px}
.btn.on{outline:2px solid var(--accent);background:rgba(255,255,255,.12)}
.btnrow{display:flex;flex-wrap:wrap;gap:8px;margin:10px 0}

/* viz */
.viz{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:clamp(14px,2.5vw,24px);margin-bottom:24px}
.viz>h2{font-size:22px}
.viz>p.d{color:var(--tx2);margin-top:-4px}
.stage{position:relative;width:100%;height:clamp(320px,52vh,520px);border-radius:16px;overflow:hidden;background:radial-gradient(ellipse at 50% 30%,#1a1f45,#07091a 70%);border:1px solid var(--line);touch-action:none}
.stage canvas{display:block;width:100%!important;height:100%!important}
.stage .hint{position:absolute;left:12px;bottom:10px;font-size:12px;color:var(--tx3);pointer-events:none;background:rgba(0,0,0,.35);padding:4px 8px;border-radius:8px}
.stage .readout{position:absolute;right:12px;top:12px;font:600 13px var(--mono);color:#fff;background:rgba(8,10,24,.78);border:1px solid var(--line2);padding:10px 12px;border-radius:12px;line-height:1.6;pointer-events:none;max-width:60%;overflow-wrap:anywhere}
.stage .readout.r1{font-family:Inter;font-weight:500}
@media(max-width:640px){.stage .readout{font-size:10.5px;padding:6px 8px;max-width:78%!important;right:6px;top:6px;line-height:1.45}.stage .hint{display:none}.ctrls input[type=range]{width:130px}}
.stage .readout .ok{color:var(--ok)}.stage .readout .bad{color:var(--bad)}
.stage .lbl3d{position:absolute;font:700 12px Inter;color:#fff;background:rgba(0,0,0,.55);padding:2px 7px;border-radius:6px;pointer-events:none;transform:translate(-50%,-50%);white-space:nowrap}
.ctrls{display:flex;flex-wrap:wrap;gap:12px 20px;align-items:center;margin-top:14px}
.ctrls label{display:flex;align-items:center;gap:10px;font-size:14px;color:var(--tx2)}
.ctrls input[type=range]{accent-color:var(--accent);width:170px}
.ctrls output{font:700 13px var(--mono);color:#fff;min-width:56px}
.legend{display:flex;flex-wrap:wrap;gap:12px;font-size:13px;color:var(--tx2);margin-top:10px}
.legend i{display:inline-block;width:12px;height:12px;border-radius:50%;margin-right:6px;vertical-align:-1px}

/* quiz */
.quiz-top{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin-bottom:14px}
.progress{flex:1;min-width:200px;height:10px;background:rgba(255,255,255,.08);border-radius:9px;overflow:hidden}
.progress i{display:block;height:100%;background:linear-gradient(90deg,var(--accent),var(--accent2));width:0;transition:width .4s}
.qcard{background:var(--card);border:1px solid var(--line);border-radius:22px;padding:clamp(18px,3vw,30px);animation:pop .35s ease}
@keyframes pop{from{opacity:0;transform:translateY(10px) scale(.98)}}
.qcard .qmeta{font:700 12px Inter;letter-spacing:.1em;color:var(--accent);text-transform:uppercase}
.qcard h3{font-size:clamp(18px,2.4vw,22px);margin:8px 0 18px;color:#fff;font-weight:600;line-height:1.4}
.opts{display:grid;gap:10px}
.opt{display:flex;gap:14px;align-items:center;text-align:left;background:rgba(255,255,255,.04);border:1.5px solid var(--line2);color:var(--tx);font:500 15.5px Inter;padding:14px 16px;border-radius:14px;cursor:pointer;transition:.15s}
.opt:hover:not(:disabled){border-color:var(--accent);background:rgba(255,255,255,.08);transform:translateX(3px)}
.opt .L{flex:0 0 34px;height:34px;border-radius:10px;display:grid;place-items:center;font:800 15px Sora;background:rgba(255,255,255,.08)}
.opt.right{border-color:var(--ok);background:rgba(34,211,154,.12)}
.opt.right .L{background:var(--ok);color:#04130d}
.opt.wrong{border-color:var(--bad);background:rgba(255,93,115,.12);animation:shake .4s}
.opt.wrong .L{background:var(--bad);color:#200}
.opt:disabled{cursor:default}
@keyframes shake{25%{transform:translateX(-6px)}75%{transform:translateX(6px)}}
.explain{margin-top:16px;padding:14px 16px;border-radius:14px;background:rgba(255,255,255,.05);border-left:4px solid var(--ok);color:var(--tx2);animation:pop .3s}
.explain.no{border-left-color:var(--bad)}
.explain b.v{display:block;font-family:Sora;font-size:16px;margin-bottom:4px}
.explain.yes b.v{color:var(--ok)}.explain.no b.v{color:var(--bad)}
.qnav{display:flex;justify-content:space-between;gap:10px;margin-top:18px;flex-wrap:wrap}
.result{text-align:center;padding:30px 10px}
.result .big{font:800 72px Sora;background:linear-gradient(90deg,var(--accent),var(--accent2));-webkit-background-clip:text;background-clip:text;color:transparent}
.ring{width:170px;height:170px;margin:0 auto 10px;border-radius:50%;display:grid;place-items:center;background:conic-gradient(var(--accent) var(--p),rgba(255,255,255,.08) 0)}
.ring div{width:140px;height:140px;border-radius:50%;background:var(--bg2);display:grid;place-items:center;font:800 38px Sora}
.qdots{display:flex;flex-wrap:wrap;gap:5px;margin:12px 0}
.qdots i{width:12px;height:12px;border-radius:4px;background:rgba(255,255,255,.1)}
.qdots i.r{background:var(--ok)}.qdots i.w{background:var(--bad)}.qdots i.c{outline:2px solid #fff}

/* problems */
.prob{background:var(--card);border:1px solid var(--line);border-radius:20px;padding:clamp(16px,2.5vw,26px);margin-bottom:18px}
.prob .ph{display:flex;gap:12px;align-items:flex-start}
.prob .pn{flex:0 0 38px;height:38px;border-radius:12px;display:grid;place-items:center;font:800 16px Sora;background:linear-gradient(135deg,var(--accent),var(--accent2));color:#0a0c16}
.prob .pq{color:#fff;font-size:16px}
.prob .pq .given{display:block;margin-top:6px;color:var(--tx2);font-size:14px}
.ansrow{display:flex;flex-wrap:wrap;gap:8px;align-items:center;margin:14px 0 0 50px}
@media(max-width:600px){.ansrow{margin-left:0}}
.ansrow input{background:#0d1024;border:1.5px solid var(--line2);color:#fff;font:600 16px var(--mono);padding:10px 12px;border-radius:11px;width:180px}
.ansrow input:focus{outline:none;border-color:var(--accent)}
.ansrow input.ok{border-color:var(--ok)}.ansrow input.no{border-color:var(--bad);animation:shake .4s}
.ansrow .unit{color:var(--tx2);font:600 14px var(--mono)}
.fb{margin:10px 0 0 50px;font-weight:600}
@media(max-width:600px){.fb{margin-left:0}}
.fb.ok{color:var(--ok)}.fb.no{color:var(--bad)}
.steps{margin:12px 0 0 50px;background:#0d1024;border:1px solid var(--line);border-radius:14px;padding:14px 18px;color:var(--tx2);animation:pop .3s}
@media(max-width:600px){.steps{margin-left:0}}
.steps ol{margin:0;padding-left:20px}
.steps li{margin:6px 0}
.steps .mono{color:#fff}

/* flashcards */
.fc-wrap{max-width:720px;margin:0 auto}
.fc-top{display:flex;justify-content:space-between;align-items:center;gap:10px;flex-wrap:wrap;margin-bottom:14px;color:var(--tx2);font-size:14px}
.fc-scene{perspective:1400px;height:clamp(300px,46vh,400px);cursor:pointer;margin-bottom:16px}
.fc{position:relative;width:100%;height:100%;transform-style:preserve-3d;transition:transform .65s cubic-bezier(.3,1.4,.5,1)}
.fc.flip{transform:rotateY(180deg)}
.fc-face{position:absolute;inset:0;backface-visibility:hidden;-webkit-backface-visibility:hidden;border-radius:24px;padding:28px;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;border:1px solid var(--line2);overflow:auto}
.fc-front{background:linear-gradient(150deg,#1b2050,#0e1130)}
.fc-front::after{content:"";position:absolute;inset:0;border-radius:24px;background:radial-gradient(circle at 80% 0%,var(--glow),transparent 55%);pointer-events:none}
.fc-back{background:linear-gradient(150deg,#122a2a,#0b1424);transform:rotateY(180deg)}
body.s-shqip .fc-back{background:linear-gradient(150deg,#2a1218,#140b16)}
body.s-fizike .fc-back{background:linear-gradient(150deg,#121a3a,#0b0d24)}
.fc-face .em{font-size:52px;margin-bottom:10px}
.fc-face .ft{font:700 clamp(20px,3vw,27px) Sora;color:#fff}
.fc-face .bt{font-size:clamp(15px,2vw,18px);color:#e4e7ff;line-height:1.55}
.fc-face .bt .mono{color:var(--accent2)}
.fc-face .cat{position:absolute;top:16px;left:18px;font:700 11px Inter;letter-spacing:.12em;text-transform:uppercase;color:var(--accent)}
.fc-face .tap{position:absolute;bottom:14px;font-size:12px;color:var(--tx3)}
.fc-btns{display:flex;justify-content:center;gap:10px;flex-wrap:wrap}
.fc-btns .btn.no{border-color:rgba(255,93,115,.5);color:#ff9aa5}
.fc-btns .btn.yes{border-color:rgba(34,211,154,.5);color:#7ff0c7}
.fc-deck{display:flex;gap:6px;flex-wrap:wrap;justify-content:center;margin-bottom:16px}

/* authors */
.carousel-wrap{position:relative;height:430px;perspective:1300px;overflow:hidden;margin:6px 0 10px}
.carousel{position:absolute;left:50%;top:40px;width:170px;height:240px;margin-left:-85px;transform-style:preserve-3d;transition:transform 1s cubic-bezier(.2,.8,.2,1)}
.acard{position:absolute;inset:0;border-radius:16px;overflow:hidden;background:#151937;border:1px solid var(--line2);box-shadow:0 20px 40px -10px rgba(0,0,0,.7);cursor:pointer;backface-visibility:hidden}
.acard img,.avatar img{width:100%;height:100%;object-fit:cover;filter:grayscale(.15) contrast(1.05)}
.acard .nm{position:absolute;left:0;right:0;bottom:0;padding:26px 10px 10px;background:linear-gradient(transparent,rgba(0,0,0,.92));font:700 14px Sora;text-align:center}
.acard .nm small{display:block;font:600 11px Inter;margin-top:2px}
.acard .var{position:absolute;top:8px;right:8px}
.initials{width:100%;height:100%;display:grid;place-items:center;font:800 54px Sora;color:#fff;background:linear-gradient(135deg,var(--accent),#2a2f6b)}
.car-ctrl{position:absolute;bottom:14px;left:0;right:0;display:flex;justify-content:center;gap:10px}
.author-detail{display:grid;grid-template-columns:200px 1fr;gap:22px;background:linear-gradient(135deg,rgba(255,255,255,.07),rgba(255,255,255,.02));border:1px solid var(--line2);border-radius:20px;padding:20px;animation:pop .35s}
@media(max-width:640px){.author-detail{grid-template-columns:1fr}.author-detail .avatar{max-width:200px;margin:0 auto}}
.avatar{width:100%;aspect-ratio:3/4;border-radius:14px;overflow:hidden;background:#151937;border:1px solid var(--line2)}
.author-detail h3{font-size:24px;margin:0 0 4px}
.author-detail .meta{color:var(--accent2);font-weight:600;font-size:14px;margin-bottom:10px}
.author-detail p{color:var(--tx2);margin:6px 0}
.author-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(150px,1fr));gap:14px;margin-top:14px}
.author-tile{background:var(--card);border:1px solid var(--line);border-radius:16px;overflow:hidden;cursor:pointer;transition:.2s;text-align:center}
.author-tile:hover{transform:translateY(-4px) rotateX(4deg);border-color:var(--accent)}
.author-tile .avatar{border-radius:0;border:0}
.author-tile b{display:block;font:700 13.5px Sora;padding:8px 6px 2px}
.author-tile span{display:block;font-size:12px;color:var(--tx3);padding-bottom:10px}

/* timeline */
.timeline{position:relative;display:flex;gap:16px;overflow-x:auto;padding:30px 4px 20px;scroll-snap-type:x mandatory;perspective:900px}
.timeline::before{content:"";position:absolute;left:0;right:0;top:56px;height:3px;background:linear-gradient(90deg,var(--accent),var(--accent2));opacity:.6;min-width:100%}
.tl-item{flex:0 0 230px;scroll-snap-align:start;position:relative;padding-top:46px}
.tl-item .dot{position:absolute;top:14px;left:18px;width:24px;height:24px;border-radius:50%;background:var(--bg);border:4px solid var(--accent);box-shadow:0 0 18px var(--glow)}
.tl-item .yr{position:absolute;top:0;left:52px;font:800 15px Sora;color:var(--accent2)}
.tl-card{background:linear-gradient(160deg,rgba(255,255,255,.09),rgba(255,255,255,.02));border:1px solid var(--line2);border-radius:16px;padding:14px;transition:transform .3s;transform:rotateY(-8deg);transform-origin:left}
.tl-card:hover{transform:rotateY(0) translateZ(20px) scale(1.03)}
.tl-card h4{font-size:15px;margin:0 0 6px;color:#fff}
.tl-card p{font-size:13px;color:var(--tx2);margin:0}

/* dialect schematic */
.dialect{display:grid;grid-template-columns:1fr;gap:0;border-radius:20px;overflow:hidden;border:1px solid var(--line2)}
.dz{padding:18px 20px;position:relative}
.dz.g{background:linear-gradient(180deg,rgba(255,77,94,.25),rgba(255,77,94,.08))}
.dz.t{background:linear-gradient(0deg,rgba(90,139,255,.25),rgba(90,139,255,.08))}
.dz h3{margin:0 0 6px!important;font-size:20px}
.dz h3::before{display:none!important}
.river{height:46px;background:#07203a;position:relative;overflow:hidden;display:flex;align-items:center;justify-content:center;font:700 13px Sora;color:#9fd8ff;letter-spacing:.12em}
.river::before{content:"";position:absolute;inset:0;background:repeating-linear-gradient(90deg,transparent 0 30px,rgba(90,209,255,.35) 30px 60px);animation:flow 3s linear infinite;mask:radial-gradient(ellipse 60% 18% at 50% 50%,#000 60%,transparent 62%) 0 0/120px 46px repeat-x}
.river span{position:relative;background:#07203a;padding:2px 12px;border-radius:999px;border:1px solid rgba(90,209,255,.4)}
@keyframes flow{to{background-position:60px 0}}
.feat-switch{display:flex;flex-wrap:wrap;gap:6px;margin:12px 0}
.compare{display:grid;grid-template-columns:1fr 1fr;gap:12px}
.compare .side{border-radius:14px;padding:14px;text-align:center}
.compare .side.g{background:rgba(255,77,94,.12);border:1px solid rgba(255,77,94,.35)}
.compare .side.t{background:rgba(90,139,255,.12);border:1px solid rgba(90,139,255,.35)}
.compare .w{font:800 clamp(20px,3vw,28px) Sora;color:#fff}
.compare small{color:var(--tx3);display:block}

/* sort game */
.sortgame{display:grid;grid-template-columns:1fr 1fr;gap:12px;margin-top:10px}
.bin{min-height:120px;border-radius:16px;padding:12px;border:2px dashed var(--line2)}
.bin.g{border-color:rgba(255,77,94,.5)}.bin.t{border-color:rgba(90,139,255,.5)}
.bin h4{margin:0 0 8px;font-size:14px}
.pool{display:flex;flex-wrap:wrap;gap:8px;justify-content:center;margin:10px 0}
.token{padding:8px 12px;border-radius:999px;background:var(--card2);border:1px solid var(--line2);font-weight:600;font-size:14px;cursor:pointer;user-select:none}
.token.sel{outline:2px solid var(--accent2)}
.token.ok{background:rgba(34,211,154,.18);border-color:var(--ok)}
.token.no{background:rgba(255,93,115,.18);border-color:var(--bad);animation:shake .4s}

/* concentric */
.concentric{position:relative;width:min(420px,100%);aspect-ratio:1;margin:10px auto}
.concentric div{position:absolute;border-radius:50%;display:flex;align-items:flex-start;justify-content:center;text-align:center;font:700 13px Sora;padding-top:6%;transition:.3s;cursor:default}
.concentric div:hover{filter:brightness(1.3)}
.concentric .c1{inset:0;background:rgba(255,179,92,.12);border:2px solid rgba(255,179,92,.6);color:#ffcf91}
.concentric .c2{inset:22%;background:rgba(255,77,94,.16);border:2px solid rgba(255,77,94,.7);color:#ffb1b9}
.concentric .c3{inset:44%;background:rgba(255,255,255,.12);border:2px solid #fff;color:#fff;align-items:center;padding:0;font-size:11px}

/* story */
.story{display:grid;grid-template-columns:repeat(auto-fit,minmax(180px,1fr));gap:14px;perspective:1000px}
.scene{height:230px;cursor:pointer}
.scene .in{position:relative;width:100%;height:100%;transform-style:preserve-3d;transition:transform .6s}
.scene.flip .in{transform:rotateY(180deg)}
.scene .s-f,.scene .s-b{position:absolute;inset:0;backface-visibility:hidden;border-radius:16px;padding:16px;display:flex;flex-direction:column;justify-content:center;align-items:center;text-align:center;border:1px solid var(--line2)}
.scene .s-f{background:linear-gradient(160deg,#2b1f3d,#120d1f)}
.scene .s-f .e{font-size:54px}
.scene .s-f b{font-family:Sora;margin-top:6px}
.scene .s-f small{color:var(--tx3)}
.scene .s-b{background:linear-gradient(160deg,#1d2a3d,#0d1220);transform:rotateY(180deg);font-size:13.5px;color:var(--tx2)}

/* tree */
.tree ul{list-style:none;margin:0;padding-left:22px;border-left:2px dashed var(--line2)}
.tree>ul{border:0;padding:0}
.tree li{position:relative;margin:8px 0}
.tree li>span{display:inline-block;padding:7px 12px;border-radius:10px;background:var(--card2);border:1px solid var(--line2);font-weight:600;font-size:14px;color:#fff;cursor:pointer}
.tree li>span.leaf{cursor:default;background:rgba(22,224,163,.12);border-color:rgba(22,224,163,.4);color:#9ff5d8}
.tree li.closed>ul{display:none}
.tree li>span::before{content:"▾ ";color:var(--accent)}
.tree li.closed>span::before{content:"▸ "}
.tree li>span.leaf::before{content:"• "}

.fg-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(200px,1fr));gap:12px}
.fg{border-radius:14px;padding:14px;background:var(--card);border:1px solid var(--line);transition:.2s}
.fg:hover{border-color:var(--accent);transform:translateY(-3px)}
.fg .g{font:800 22px var(--mono);color:var(--accent)}
.fg b{display:block;margin:4px 0 2px;font-family:Sora}
.fg small{color:var(--tx2);font-family:var(--mono)}

svg text{font-family:Inter,sans-serif}
.svgbox{width:100%;background:radial-gradient(ellipse at 50% 30%,#1a1f45,#07091a 75%);border-radius:16px;border:1px solid var(--line)}

.toast{position:fixed;left:50%;bottom:24px;transform:translateX(-50%) translateY(120px);background:#141838;border:1px solid var(--line2);padding:12px 18px;border-radius:14px;font-weight:600;z-index:100;transition:.35s;box-shadow:var(--shadow)}
.toast.show{transform:translateX(-50%) translateY(0)}
.empty{color:var(--tx3);text-align:center;padding:30px}

/* ---------- voice / TTS ---------- */
.tts-btn{display:inline-flex;align-items:center;gap:6px;border:1px solid var(--line2);background:rgba(255,255,255,.07);color:var(--tx);font:600 12.5px Inter;padding:6px 11px;border-radius:999px;cursor:pointer;transition:.15s;vertical-align:middle;white-space:nowrap}
.tts-btn:hover{background:var(--accent);color:#0a0c16;border-color:transparent}
.lesson>h2 .tts-btn{margin-left:auto}
.lesson>h2{flex-wrap:wrap}
.tts-reading{outline:2px solid var(--accent);outline-offset:4px;border-radius:8px;background:rgba(255,255,255,.06)!important;transition:outline .2s}
.tts-fab{position:fixed;right:18px;bottom:18px;z-index:120;width:52px;height:52px;border-radius:50%;border:0;font-size:22px;cursor:pointer;background:linear-gradient(135deg,var(--accent),var(--accent2));box-shadow:0 10px 30px -8px var(--glow)}
.tts-bar{position:fixed;right:18px;bottom:80px;z-index:121;width:min(380px,calc(100vw - 32px));background:rgba(17,20,42,.96);backdrop-filter:blur(14px);border:1px solid var(--line2);border-radius:18px;padding:14px 14px 10px;box-shadow:var(--shadow);transform:translateY(20px);opacity:0;pointer-events:none;transition:.25s}
.tts-bar.show{transform:none;opacity:1;pointer-events:auto}
.tts-st{font-size:13.5px;color:var(--tx2);padding-right:24px;min-height:20px;line-height:1.4}
.tts-st b{color:#fff}
.tts-row{display:flex;gap:6px;align-items:center;margin:10px 0 6px;flex-wrap:wrap}
.tts-row button{width:40px;height:40px;border-radius:12px;border:1px solid var(--line2);background:var(--card2);color:#fff;font-size:16px;cursor:pointer}
.tts-row .tts-play{background:linear-gradient(135deg,var(--accent),var(--accent2));color:#0a0c16;border:0}
.tts-row button:disabled{opacity:.5}
.tts-row select{background:#0d1024;color:#fff;border:1px solid var(--line2);border-radius:10px;padding:8px;font:600 13px Inter}
.tts-eng{color:var(--tx3);font-size:11.5px}
.tts-x{position:absolute;top:8px;right:10px;background:none;border:0;color:var(--tx3);font-size:16px;cursor:pointer}
.fc-face .tts-btn{position:absolute;top:12px;right:14px;z-index:2}