:root{color-scheme:light;--paper: #f5f3ec;--paper-wash-sage: #e5ebdf;--paper-wash-sand: #efe4d5;--ink: #243c35;--muted: #66766e;--green: #285a46;--green-deep: #1e4837;--on-green: #f6f4e9;--on-green-strong: #ffffff;--focus: #bb7238;--card: #fffef9;--card-revealed: #f4faf0;--card-line: #e4e4d9;--card-under: #faf9f2;--card-under-line: #dedfd3;--card-meta: #758379;--card-hint: #718174;--card-front-dim: #63776b;--card-shadow: 0 13px 35px #3f463211;--card-shadow-hover: 0 16px 40px #3f46321c;--line: #d7ddd1;--control: #fffef980;--control-hover: #e5eddf;--kbd-line: #d8dccf;--footer-dot: #7d9777;--highlight: #f4dd83;--highlight-ink: #293c31;--segment: #eeeee5;--segment-line: #dce0d6;--segment-ink: #596c61;--select-line: #d8dcd2;--select: #ffffff70;--focus-note: #5c705f;--definition-line: #dce5d6;--status-line: #b4c3b0;--status: #fffef970;--field-line: #c3cbbd;--warn: #9c4424;--warn-wash: #f8ebe2;--ok-wash: #e7f0e1;--font-sans: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;--font-serif: ui-serif, Georgia, serif;--radius-card: 22px;--radius-control: 12px;--focus-width: 3px;--focus-offset: 4px;--gutter: 5vw}*{box-sizing:border-box}[hidden]{display:none!important}html{-webkit-text-size-adjust:100%;text-size-adjust:100%}body{margin:0;min-height:100svh;display:flex;flex-direction:column;background:var(--paper);color:var(--ink);font-family:var(--font-sans);background-image:radial-gradient(ellipse at 7% 47%,var(--paper-wash-sage) 0,transparent 47%),radial-gradient(ellipse at 95% 80%,var(--paper-wash-sand) 0,transparent 43%)}app-root{flex:1;display:flex;flex-direction:column;min-width:0}.topbar{display:flex;align-items:center;justify-content:space-between;gap:16px;padding:27px var(--gutter)}.brand{display:flex;align-items:center;gap:10px;color:var(--ink);font-size:18px;font-weight:750;text-decoration:none;letter-spacing:-.6px;white-space:nowrap}.brand-icon{display:grid;place-items:center;flex:none;width:34px;height:34px;border-radius:50%;background:var(--green);color:var(--on-green);font-size:28px;font-weight:400;font-variant-emoji:text}.header-note{font-size:12px;color:var(--muted);text-align:right}.view{flex:1;display:grid;place-items:center;min-width:0;padding:22px 24px 30px}.view>router-outlet{display:none}.practice{width:100%;max-width:850px;text-align:center}.eyebrow{font-size:10px;font-weight:800;letter-spacing:2.4px;text-transform:uppercase;color:var(--green);margin:0 0 13px}h1{font-family:var(--font-serif);font-size:clamp(28px,4vw,39px);font-weight:400;letter-spacing:-1.3px;line-height:1.2;margin:0}.lede{font-size:13px;line-height:1.6;color:var(--muted);margin:12px 0 27px}.rules{font-size:11px;line-height:1.6;color:var(--muted);margin:0}kbd{font:inherit;border:1px solid var(--kbd-line);border-radius:4px;padding:2px 5px}.cta{display:inline-flex;justify-content:center;align-items:center;min-height:48px;padding:0 30px;border-radius:var(--radius-control);background:var(--green);color:var(--on-green-strong);font-size:16px;font-weight:650;text-decoration:none}.cta:hover{background:var(--green-deep)}.text-link{color:var(--green);text-underline-offset:3px}.page{align-self:start;width:100%;max-width:560px;padding-top:18px;text-align:left}.page.wide{max-width:720px}.page-head{margin:0 0 26px}.page-head .lede{margin:10px 0 0;font-size:14px}.entry{width:100%;text-align:center}.entry-head{margin:0 0 24px}.entry-head .lede{margin:12px auto 0;max-width:340px}.entry .sheet{text-align:left}.entry-foot{margin:20px 0 0;font-size:14px}.sheet{background:var(--card);border:1px solid var(--card-line);border-radius:var(--radius-card);box-shadow:var(--card-shadow);padding:26px 28px}.sheet+.sheet{margin-top:22px}.sheet-title{font-family:var(--font-serif);font-size:22px;font-weight:400;letter-spacing:-.5px;margin:0 0 4px}.sheet-note{font-size:13px;line-height:1.6;color:var(--muted);margin:0 0 18px}.stack{display:grid;gap:12px}.btn{display:inline-flex;justify-content:center;align-items:center;min-height:48px;padding:0 24px;border:1px solid transparent;border-radius:var(--radius-control);background:var(--green);color:var(--on-green-strong);font:inherit;font-size:15px;font-weight:650;text-decoration:none;cursor:pointer}.btn:hover:enabled{background:var(--green-deep)}.btn:disabled{opacity:.55;cursor:default}.btn.quiet{background:transparent;border-color:var(--field-line);color:var(--green)}.btn.quiet:hover:enabled{background:var(--control-hover)}.btn.risky{background:var(--warn)}.btn.risky:hover:enabled{background:#7f3519}.btn.small{min-height:44px;padding:0 16px;font-size:14px}.actions{display:flex;flex-wrap:wrap;align-items:center;gap:10px 14px;margin-top:8px}.notice{min-height:20px;margin:0;font-size:13px;line-height:20px;color:var(--muted)}.notice.bad{color:var(--warn);font-weight:550}.notice.good{color:var(--green);font-weight:550}.notice.tail:empty,.notice.tail.idle{position:absolute;min-height:0}.dialog-foot .notice:empty{min-height:0}.dialog-foot .notice:not(:empty){margin-bottom:4px}.dialog{border:none;padding:0;background:transparent;width:100%;max-width:min(520px,calc(100vw - 24px));max-height:calc(100dvh - 24px);color:var(--ink)}.dialog::backdrop{background:#243c3573}.dialog-panel{display:flex;flex-direction:column;max-height:calc(100dvh - 24px);background:var(--card);border:1px solid var(--card-line);border-radius:var(--radius-card);box-shadow:var(--card-shadow);text-align:left}.dialog-head{padding:24px 26px 0}.dialog-title{font-family:var(--font-serif);font-size:24px;font-weight:400;letter-spacing:-.6px;margin:0}.dialog-body{overflow-y:auto;min-height:0;padding:18px 26px 16px}.dialog-foot{padding:12px 26px 22px;border-top:1px solid var(--card-line)}.skeleton{width:100%;max-width:420px;display:grid;gap:14px;justify-items:center;opacity:0;animation:skeleton-in .3s ease .4s forwards}.skeleton-bar{height:14px;width:60%;border-radius:7px;background:var(--line);opacity:.6}.skeleton-bar.title{height:30px;width:80%}.skeleton-bar.short{width:40%}@keyframes skeleton-in{to{opacity:1}}.equation{font-size:clamp(46px,9vw,74px);letter-spacing:-3px;font-weight:550;font-variant-numeric:tabular-nums;line-height:1.15}.answer{font-size:44px;font-weight:650;color:var(--green);line-height:1.1;margin:18px 0 0}.flashcard.revealed .equation{font-size:46px;color:var(--card-front-dim)}.modes{display:grid;grid-template-columns:repeat(var(--segments, 4),minmax(0,1fr));gap:4px;width:100%;max-width:660px;min-width:0;margin:0 auto;padding:5px;border:1px solid var(--segment-line);border-radius:14px;background:var(--segment)}.modes label{position:relative;min-width:0;cursor:pointer}.modes input{position:absolute;inset:0;width:100%;height:100%;margin:0;opacity:0;cursor:pointer}.modes span{display:flex;justify-content:center;align-items:center;gap:7px;min-height:44px;padding:0 4px;border-radius:10px;color:var(--segment-ink);font-size:12px;font-weight:650;text-align:center}.modes b{font-size:21px;font-weight:400}.modes input:checked+span{background:var(--green);color:var(--on-green-strong);box-shadow:0 2px 4px #243c3515}.modes input:focus-visible+span{outline:var(--focus-width) solid var(--focus);outline-offset:var(--focus-offset)}.pick{display:flex;flex-wrap:wrap;justify-content:center;align-items:center;gap:8px 12px;margin:17px 0 24px;font-size:12px;color:var(--muted)}.pick select,select.plain{min-height:44px;max-width:100%;padding:8px 10px;border:1px solid var(--select-line);border-radius:7px;background:var(--select);color:var(--ink);font:inherit;font-size:16px;cursor:pointer}.topic{margin:24px 0}.topic h2{font-family:var(--font-serif);font-size:26px;font-weight:400;margin:0 0 9px}.topic p{font-size:13px;line-height:1.6;color:var(--muted);margin:4px 0}.status{max-width:600px;margin:32px auto;padding:32px;border:1px dashed var(--status-line);border-radius:18px;background:var(--status);color:var(--muted);font-size:14px;line-height:1.7}.word{display:block;font-size:clamp(28px,5vw,54px);font-weight:600;letter-spacing:-1px;line-height:1.2;overflow-wrap:anywhere}mark{padding:0 2px;border-radius:5px;background:var(--highlight);color:var(--highlight-ink)}.focus-note{font-size:14px;line-height:1.7;color:var(--focus-note);margin:18px 0 0;overflow-wrap:anywhere;white-space:pre-line}.flashcard.reading.revealed .word{font-size:36px}.pronunciation{font-size:14px;color:var(--muted);margin:6px 0 0;overflow-wrap:anywhere}.definition{margin-top:18px;padding-top:14px;border-top:1px solid var(--definition-line)}.definition h3{font-size:14px;margin:0 0 7px}.definition p{margin:0;font-size:16px;line-height:1.65;white-space:pre-wrap;overflow-wrap:anywhere}a:focus-visible,button:focus-visible,select:focus-visible,main h1:focus-visible,[role=button]:focus-visible{outline:var(--focus-width) solid var(--focus);outline-offset:var(--focus-offset)}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}@media(max-width:540px){.topbar{padding:20px 23px}.header-note,.keyboard{display:none}.view{padding:15px 18px 25px}.page{padding-top:6px}.sheet{padding:22px 18px}.dialog-head{padding:20px 18px 0}.dialog-body{padding:16px 18px 14px}.dialog-foot{padding:12px 18px 18px}.actions .btn{flex:1 1 auto}.sheet .actions .btn{flex-basis:100%}.lede{max-width:280px;margin:12px auto 23px}.flashcard:not(.revealed) .equation{font-size:42px;letter-spacing:-2px}.modes span{font-size:11px;gap:4px}.modes b{font-size:17px}.modes.many{grid-template-columns:repeat(2,minmax(0,1fr))}.modes.many span{font-size:13px}.status{padding:24px 18px}.definition p{font-size:15px}}@media(prefers-reduced-motion:reduce){*{transition:none!important}.skeleton{animation-duration:.01s}}@media print{.no-print{display:none!important}}