/* Capitole (home), chapter and practice basics, landing intro */
/* home */
.cont{display:flex;align-items:center;justify-content:space-between;gap:16px;flex-wrap:wrap;background:var(--acc-w);border-radius:14px;padding:18px 20px;margin-bottom:28px}
.cont .k{font-size:13px;font-weight:700;color:var(--acc)}
.cont .tt{font-size:18px;font-weight:900;line-height:24px}
.cont .mt{font-size:13px;color:var(--muted)}
.goal{background:var(--panel);border-radius:14px;padding:16px 18px;margin-bottom:14px}
.goal-top{display:flex;align-items:center;gap:16px}
.gstep{display:flex;align-items:center;justify-content:space-between;gap:10px;flex-wrap:wrap;margin-top:12px;padding-top:12px;border-top:1px solid var(--line)}
.gstep label{font-size:14px;font-weight:700}
.gs-ctl{display:flex;align-items:center;gap:6px}
.gs-ctl button{width:36px;height:36px;border-radius:50%;border:1.5px solid var(--line2);background:var(--card);color:var(--ink);font:inherit;font-size:20px;font-weight:800;line-height:1;cursor:pointer}
.gs-ctl button:hover:not(:disabled){border-color:var(--acc);color:var(--acc)}
.gs-ctl button:disabled{opacity:.4;cursor:default}
.gs-ctl input{width:58px;height:36px;border:1.5px solid var(--line2);background:var(--card);color:var(--ink);border-radius:10px;font:inherit;font-weight:900;font-size:17px;text-align:center;-moz-appearance:textfield}
.gs-ctl input::-webkit-inner-spin-button,.gs-ctl input::-webkit-outer-spin-button{-webkit-appearance:none;margin:0}
.gs-ctl input:focus{outline:none;border-color:var(--acc)}
.goal-ring{--p:0;flex:none;width:64px;height:64px;border-radius:50%;display:grid;place-items:center;
  background:conic-gradient(var(--sun) calc(var(--p)*1%),var(--line) 0);transition:background .3s}
.goal.met .goal-ring{background:var(--good)}
.goal-ring span{width:50px;height:50px;border-radius:50%;background:var(--panel);display:flex;align-items:baseline;justify-content:center;padding-top:14px;
  font-size:18px;font-weight:900;font-variant-numeric:tabular-nums}
.goal-ring small{font-size:11px;color:var(--muted)}
.goal-t{flex:1;min-width:0}
.goal .k{font-size:12px;font-weight:800;letter-spacing:.05em;text-transform:uppercase;color:var(--muted)}
.goal .tt{font-size:17px;font-weight:800;line-height:24px}
.goal.met .tt{color:var(--good)}
.goal .goal-m{font-size:13px;color:var(--muted);display:flex;align-items:center;gap:6px;flex-wrap:wrap}
.goal .gf{display:inline-flex;align-items:center;gap:3px;color:var(--sun);font-weight:800}
.goal .gf svg{width:15px;height:15px}
.goal .lnk{font-size:13px}
.hb-toast{position:fixed;left:50%;bottom:24px;z-index:80;display:flex;align-items:center;gap:12px;max-width:min(440px,calc(calc(100vw / var(--rz)) - 32px));
  background:var(--card);color:var(--ink);border-radius:18px;padding:10px 40px 10px 12px;box-shadow:0 14px 40px rgba(20,30,60,.22),0 0 0 1px var(--line);
  transform:translate(-50%,140%);opacity:0;transition:transform .35s cubic-bezier(.2,1.3,.4,1),opacity .25s;pointer-events:none}
.hb-toast.in{transform:translate(-50%,0);opacity:1;pointer-events:auto}
.hb-toast.out{transform:translate(-50%,140%);opacity:0}
.hb-toast.big{border:2px solid var(--sun)}
.hb-toast .hb-m{width:58px;height:55px;flex:none}
.hb-toast b{display:block;font-size:16px;line-height:21px}
.hb-toast span{display:block;font-size:13.5px;line-height:19px;color:var(--muted)}
.hb-toast .x{position:absolute;top:6px;right:8px;border:none;background:none;font-size:20px;line-height:1;color:var(--muted);cursor:pointer;padding:4px}
@media (prefers-reduced-motion:reduce){.hb-toast{transition:opacity .2s}}
.stats{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;margin-bottom:28px}
.stat{background:var(--panel);border-radius:12px;padding:12px 14px}
.stat b{display:block;font-size:22px;line-height:28px;font-weight:900;font-variant-numeric:tabular-nums}
.stat span{font-size:13px;color:var(--muted)}
.group{margin-bottom:24px}
.gh{display:flex;justify-content:space-between;align-items:baseline;gap:12px;margin:0 4px 10px}
.gh .pts{font-size:13px;color:var(--muted)}
.chapters{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.ch{display:flex;flex-direction:column;gap:10px;text-align:left;background:var(--panel);border:2px solid transparent;border-radius:14px;padding:14px 16px;cursor:pointer;min-width:0}
.ch:hover{border-color:var(--line)}
.ch .r1{display:flex;align-items:center;gap:10px}
.ch .nm{font-weight:700;font-size:15px;line-height:20px;flex:1;min-width:0}
.ch .r2{display:flex;justify-content:space-between;align-items:center;gap:8px;font-size:13px;color:var(--muted)}
.ch .pill{font-size:12px;line-height:18px;font-weight:700;color:var(--acc);background:var(--acc-w);border-radius:999px;padding:1px 8px;white-space:nowrap}
.legend{display:flex;gap:16px;flex-wrap:wrap;font-size:13px;color:var(--muted);margin:4px 4px 0}
.legend span{display:flex;align-items:center;gap:6px}
.legend .m{width:14px;height:14px;border-radius:5px}

/* chapter */
.chhead{display:flex;justify-content:space-between;align-items:flex-end;gap:16px;flex-wrap:wrap;margin-bottom:20px}
.prog{display:flex;align-items:center;gap:10px;font-size:13px;color:var(--muted)}
.box{background:var(--panel);border-radius:14px;padding:16px;margin-bottom:16px}
.box h2{margin:0 4px 10px}
.where{display:flex;flex-wrap:wrap;gap:8px}
.where span{background:var(--bg);border-radius:999px;padding:3px 10px;font-size:13px}
.topics{margin:0;padding-left:20px;color:var(--ink)}
.topics li{margin:2px 0}
.ex{display:flex;align-items:center;gap:12px;width:100%;background:var(--bg);border:2px solid transparent;border-radius:10px;padding:9px 12px;margin-bottom:8px;text-align:left;cursor:pointer}
.ex:hover{border-color:var(--line)}
.ex .t{flex:1;min-width:0}
.ex .meta{font-size:13px;color:var(--muted);flex:none}
.ex.off{cursor:default;color:var(--muted)}
.ex.off:hover{border-color:transparent}

/* practice */
.card{background:var(--panel);border-radius:14px;padding:22px}
/* at the bottom of the practice page, quiet: whoever wants to report finds it, nobody else is distracted */
.rep-line{margin:14px 0 0;text-align:center}
/* "?" in the exercise card's corner: report a mistake */
.app.prac .ex-card{position:relative}
.rep-q{position:absolute;top:10px;right:10px;z-index:2;width:30px;height:30px;padding:0;border-radius:50%;border:1.5px solid var(--line2);
  background:var(--card);color:var(--muted);font:800 15px/1 var(--font);cursor:pointer;display:grid;place-items:center}
.rep-q:hover,.rep-q:focus-visible{color:var(--acc);border-color:var(--acc)}
.app.prac .ex-card>.rep-q{width:30px;max-width:none;margin:0}   /* the card's children are full width at ≥1200px */
@media (max-width:760px){.rep-q{top:8px;right:8px;width:28px;height:28px;font-size:14px}.app.prac .ex-card .src{margin-right:30px}}
.rep-btn{border:none;background:none;padding:4px 6px;font:500 12px var(--font);color:var(--muted);cursor:pointer;opacity:.65}
.rep-btn:hover{opacity:1;text-decoration:underline}
.rep-dlg.dlg{width:min(420px,calc(calc(100vw / var(--rz)) - 32px))}
.rep{padding:20px 22px 18px}
.rep h2{margin:0 0 2px;font-size:20px}
.rep-s{margin:0 0 12px;font-size:13px;color:var(--muted)}
.rep-k{display:flex;flex-wrap:wrap;gap:6px;margin-bottom:10px}
.rep-k button{border:1.5px solid var(--line2);background:var(--card);color:var(--ink);border-radius:999px;padding:6px 12px;font:600 13px var(--font);cursor:pointer}
.rep-k button[aria-checked="true"]{border-color:var(--bad);background:var(--bad-w);color:var(--bad)}
.rep textarea{width:100%;border:1.5px solid var(--line2);background:var(--card);color:var(--ink);border-radius:12px;padding:8px 10px;font:500 14px var(--font);resize:vertical}
.rep textarea:focus{outline:none;border-color:var(--acc)}
.rep-e{margin:6px 0 0;font-size:13px;color:var(--bad)}
.rep-b{display:flex;gap:8px;margin-top:12px}
.rep-b .btn{flex:1}
.src{display:inline-block;font-size:12px;line-height:18px;color:var(--muted);background:var(--bg);border-radius:999px;padding:4px 10px;margin-bottom:12px}
.st{font-size:17px;line-height:29px}
.st i,.step i{font-style:italic}
math{font-size:1em}
.ans{display:flex;gap:12px;align-items:center;flex-wrap:wrap;margin-top:18px}
.f{display:flex;align-items:center;gap:6px;font-style:italic;color:var(--muted)}
.f input{width:62px;height:40px;border-radius:10px;border:2px solid var(--sq);background:var(--bg);text-align:center;font:400 16px var(--font);color:var(--ink);outline:none}
.f input:focus{border-color:var(--acc)}
.f input.ok{border-color:var(--good);background:var(--good-w)}
.f input.no{border-color:var(--bad);background:var(--bad-w)}
.fb{display:flex;align-items:center;gap:10px;margin-top:16px;border-radius:10px;padding:10px 14px;font-weight:700;font-size:14.5px;line-height:20px}
.fb svg{width:18px;height:18px;flex:none}
.fb.ok{background:var(--good-w);color:var(--good)}
.fb.no{background:var(--bad-w);color:var(--bad)}
.sol{margin-top:16px}
.sol h3{font-size:13px;color:var(--muted);margin:0 0 6px;font-weight:700}
.step{display:flex;gap:12px;align-items:baseline;padding:7px 0}
.step .n{width:24px;height:24px;flex:none;border-radius:50%;background:var(--acc-w);color:var(--acc);font-weight:900;font-size:13px;line-height:24px;text-align:center}
.step .tx{flex:1;min-width:0}
.step .pp{flex:none;font-size:12px;line-height:18px;font-weight:700;color:var(--muted);background:var(--bg);border-radius:999px;padding:2px 8px;font-variant-numeric:tabular-nums}
.foot{display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;margin-top:18px}
.dots{display:flex;gap:6px}
.dots i{width:28px;height:8px;border-radius:4px;background:var(--line)}
.dots i.d{background:var(--acc)} .dots i.c{background:var(--acc-w);box-shadow:inset 0 0 0 2px var(--acc)}
.acts{display:flex;align-items:center;gap:16px}
.skip{background:none;border:none;padding:0;color:var(--muted);font-weight:700;font-size:14px;cursor:pointer}
.skip:hover{color:var(--ink)}
.note{margin-top:14px;font-size:13px;color:var(--muted)}

/* ---------- landing: a new way to learn ---------- */
.nou{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:16px}
.nou .col{border-radius:16px;padding:24px 26px}
.nou .old{background:var(--panel)}
.nou .new{background:var(--card);border:2px solid var(--acc);box-shadow:0 6px 0 var(--acc-w)}
.nou h3{margin:0 0 16px;font-size:13px;line-height:18px;font-weight:800;letter-spacing:.06em;text-transform:uppercase;color:var(--muted)}
.nou .new h3{color:var(--acc)}
.nou ul{list-style:none;margin:0;padding:0;display:grid;gap:14px}
.nou li{display:flex;gap:12px;align-items:flex-start;font-size:16px;line-height:24px}
.nou li i{flex:none;width:24px;height:24px;border-radius:50%;display:grid;place-items:center}
.nou li svg{width:13px;height:13px}
.nou .old li{color:var(--muted)} .nou .old li i{background:var(--line);color:var(--muted)}
.nou .new li{font-weight:600} .nou .new li i{background:var(--acc);color:var(--on-acc)}
@media (max-width:820px){.nou{grid-template-columns:1fr}}