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solid;border-inline-end-color:#0000;border-radius:50%;block-size:1em;inline-size:1em;margin-inline-start:.4em;animation:0s .3s forwards pending-in,.8s linear infinite pending-spin;display:inline-block}@keyframes pending-in{to{opacity:1}}@keyframes pending-spin{to{transform:rotate(1turn)}}@media (prefers-reduced-motion:reduce){button.is-pending:after,.spinner{animation:0s .3s forwards pending-in}}.btn[aria-pressed=true]{background:var(--c-primary-soft-2);border-color:var(--c-primary-border)}.run-head{gap:var(--s-3) var(--s-5);color:var(--c-muted);flex-wrap:wrap;align-items:baseline;margin-block-end:var(--s-4);scroll-margin-block-start:var(--s-4);font-size:.95rem;display:flex}.run-head .timer{font-variant-numeric:tabular-nums;color:var(--c-text);font-weight:600}.run-head .timer.low{color:var(--c-err)}.run-head .stopwatch{color:var(--c-muted);font-weight:400}.q{margin-block-end:var(--s-5)}.q .stem{margin-block-end:var(--s-2);font-size:1.15rem;font-weight:600}.q .stem+.tr{margin-block-end:var(--s-4)}.tr{color:var(--c-muted)}.options{margin:0 0 var(--s-4);gap:var(--s-2);padding:0;list-style:none;display:grid}.test-col{max-inline-size:48rem;margin-inline:auto}.option{text-align:start;inline-size:100%;font:inherit;padding:var(--s-3) var(--s-4);border:1px solid var(--c-border);border-radius:var(--radius);background:var(--c-surface);color:var(--c-text);cursor:pointer;grid-template-columns:1.6em 1fr;display:grid}.option:hover{border-color:var(--c-border-strong);background:var(--c-surface-hover)}.option[aria-pressed=true],.option.chosen{border-color:var(--c-primary-border);background:var(--c-primary-soft-2)}.option.correct{border-color:var(--c-ok-border);background:var(--c-ok-bg)}.option.wrong{border-color:var(--c-err-border);background:var(--c-err-bg)}.option:disabled{cursor:default}.option .mark{grid-row:1/span 2;font-weight:700}.option>:not(.mark){grid-column:2}.verdict{font-weight:700}.verdict.ok{color:var(--c-ok)}.verdict.err{color:var(--c-err)}.explain{background:var(--c-note);border-radius:var(--radius);padding:var(--s-3) var(--s-4);margin-block:var(--s-3) var(--s-4)}.run-nav{gap:var(--s-3);margin-block:var(--s-4);justify-content:space-between;align-items:flex-start;display:flex}.run-nav-forward{justify-content:flex-end;gap:var(--s-3);flex-wrap:wrap;display:flex}@media (width<=40rem){.run-nav-forward .btn{min-inline-size:8rem}}.navigator{gap:var(--s-1);margin-block:0 var(--s-4);flex-wrap:wrap;display:flex}.navigator button{block-size:2.4rem;inline-size:2.4rem;font:inherit;border:1px solid var(--c-border);background:var(--c-surface);color:var(--c-text);cursor:pointer;border-radius:6px;font-size:.85rem}.navigator button.answered{background:var(--c-primary-soft-2);border-color:var(--c-primary-border)}.navigator button.right{background:var(--c-ok-bg);border-color:var(--c-ok-border);color:var(--c-ok)}.navigator button.wrong{background:var(--c-err-bg);border-color:var(--c-err-border);color:var(--c-err)}.navigator-label{margin-block:var(--s-4) var(--s-2)}.navigator button[aria-current=true]{outline:2px solid var(--c-primary)}.result{text-align:center;padding-block:var(--s-5)}.all-right{margin-block:var(--s-2);padding:var(--s-2) var(--s-4);background:var(--c-ok-bg);border:1px solid var(--c-ok-border);color:var(--c-ok);border-radius:999px;font-weight:600;display:inline-block}.test-col:has(.result)>h1{text-align:center;margin-block-end:0}.result .big{margin:0;font-size:2.2rem;font-weight:700}.exam-pick{align-items:center;gap:var(--s-2) var(--s-3);margin-block:var(--s-4) var(--s-5);flex-wrap:wrap;display:flex}.modes{gap:var(--s-3);margin-block:var(--s-4);display:grid}.modes .card{cursor:pointer;border-color:var(--c-border)}.modes .card[aria-pressed=true]{border-color:var(--c-primary-border);background:var(--c-primary-soft-2)}.modes .card h3{margin-block-end:var(--s-1)}.modes .card p{color:var(--c-muted);margin:0;font-size:.95rem}.hero{padding:var(--s-5) var(--s-4) var(--s-4);margin-block:var(--s-2) var(--s-7);border-radius:calc(var(--radius) * 1.6);background:linear-gradient(135deg, var(--c-primary-soft), var(--c-surface) 70%);border:1px solid var(--c-border)}@media (width>=60rem){.hero{padding:var(--s-7) var(--s-7) var(--s-6)}}.hero h1{letter-spacing:-.01em;max-inline-size:24ch;font-size:clamp(1.4rem,4.5vw + .4rem,2.6rem)}.hero .lead{max-inline-size:var(--measure);font-size:1.1rem}.eyebrow{text-transform:uppercase;letter-spacing:.08em;color:var(--c-primary-text);margin-block-end:var(--s-3);font-size:.8rem;font-weight:600}.trust{gap:var(--s-2) var(--s-4);color:var(--c-muted);flex-wrap:wrap;margin:0;padding:0;font-size:.9rem;list-style:none;display:flex}.trust li:before{content:"✓ ";color:var(--c-ok)}.exams{grid-template-columns:repeat(auto-fit,minmax(19rem,1fr));margin-block-end:var(--s-7)}.exam-card{gap:var(--s-4);padding:var(--s-4);flex-direction:column;display:flex}@media (width>=40rem){.exam-card{padding:var(--s-5)}}.exam-card>*,.exam-card .numbers{margin:0}.exam-card-head{align-items:center;gap:var(--s-3);display:flex}.exam-card-head h3{margin:0;font-size:clamp(1.1rem,1.5vw + .75rem,1.3rem)}.exam-card-head p{margin:0}.exam-card .more{color:var(--c-primary-text);margin-block-start:auto;font-weight:600}.exam-card:hover .more{text-decoration:underline}.numbers{gap:var(--s-3);margin:var(--s-4) 0;grid-template-columns:repeat(3,1fr);display:grid}.numbers div{align-content:start;display:grid}.numbers dd{font-variant-numeric:tabular-nums;order:-1;margin:0;font-size:1.8rem;font-weight:700;line-height:1.1}.numbers dt{color:var(--c-muted);text-transform:uppercase;letter-spacing:.04em;font-size:.75rem}.numbers-strip{text-align:center;padding:var(--s-3) 0;background:var(--c-bg);border:1px solid var(--c-border);border-radius:var(--radius);grid-template-columns:repeat(3,minmax(0,1fr));gap:0}.numbers-strip div{padding-inline:var(--s-1);min-inline-size:0}.numbers-strip dt{letter-spacing:.02em;hyphens:auto;font-size:.7rem}@media (width>=40rem){.numbers-strip div{padding-inline:var(--s-4)}.numbers-strip dt{font-size:.75rem}}.numbers-strip div+div{border-inline-start:1px solid var(--c-border)}.numbers-strip dd{font-size:1.6rem}.area-1{--a-bg:var(--area-1-bg);--a-soft:var(--area-1-soft);--a-border:var(--area-1-border);--a-solid:var(--area-1-solid);--a-text:var(--area-1-text)}.area-2{--a-bg:var(--area-2-bg);--a-soft:var(--area-2-soft);--a-border:var(--area-2-border);--a-solid:var(--area-2-solid);--a-text:var(--area-2-text)}.area-3{--a-bg:var(--area-3-bg);--a-soft:var(--area-3-soft);--a-border:var(--area-3-border);--a-solid:var(--area-3-solid);--a-text:var(--area-3-text)}.areas{gap:var(--s-5);display:grid}.area{background:var(--a-bg);border:1px solid var(--a-border);border-radius:calc(var(--radius) * 1.6);padding:var(--s-4) var(--s-3) var(--s-3)}@media (width>=40rem){.area{padding:var(--s-5)}}.area-head{align-items:center;gap:var(--s-3);padding-inline:var(--s-1);margin-block-end:var(--s-4);display:flex}.area-head h3{margin:0;font-size:1.2rem}.area-head p{margin:0}.area-num{background:var(--a-solid);color:#fff;font-variant-numeric:tabular-nums;border-radius:50%;flex:none;place-items:center;block-size:2.25rem;inline-size:2.25rem;font-weight:700;display:grid}.topic-cards{gap:var(--s-3)}.topic-card{align-items:flex-start;gap:var(--s-3);padding:var(--s-3) var(--s-4);display:flex}.topic-card:hover{border-color:var(--a-border);background:var(--c-surface);box-shadow:0 2px 10px #21201c14}.topic-card>div{min-inline-size:0}.topic-card h4{margin:0 0 var(--s-1);color:var(--c-primary-text);font-size:1.05rem;line-height:1.3}.topic-meta{margin:0 0 var(--s-1);color:var(--c-text);align-items:center;gap:var(--s-2);flex-wrap:wrap;font-size:.85rem;font-weight:600;display:flex}.lessons-list{-webkit-line-clamp:2;-webkit-box-orient:vertical;margin:0;display:-webkit-box;overflow:hidden}.icon-tile{border-radius:var(--radius);background:var(--a-soft,var(--c-primary-soft));block-size:2.5rem;inline-size:2.5rem;color:var(--a-text,var(--c-primary-text));flex:none;place-items:center;display:grid}.icon-tile svg{block-size:1.4rem;inline-size:1.4rem}.icon-tile-lg{block-size:3.25rem;inline-size:3.25rem}.icon-tile-lg svg{block-size:1.8rem;inline-size:1.8rem}.icon-tile-xl{border-radius:calc(var(--radius) * 1.4);background:var(--c-primary-soft-2);block-size:3.5rem;inline-size:3.5rem}.icon-tile-xl svg{block-size:2rem;inline-size:2rem}@media (width>=40rem){.icon-tile-xl{block-size:6.5rem;inline-size:6.5rem}.icon-tile-xl svg{stroke-width:1.5px;block-size:3.6rem;inline-size:3.6rem}}.badge-quiet{border:1px solid var(--c-border);color:var(--c-muted);background:0 0;font-weight:400}.topic-head{align-items:flex-start;gap:var(--s-4);padding:var(--s-4);background:var(--a-bg);border:1px solid var(--a-border);border-radius:calc(var(--radius) * 1.6);margin-block-end:var(--s-5);display:flex}@media (width>=40rem){.topic-head{padding:var(--s-5)}}.topic-head .icon-tile{background:var(--c-surface)}.topic-head .eyebrow{color:var(--a-text);margin-block-end:var(--s-1)}.topic-head .eyebrow a{color:inherit;text-decoration:none}.topic-head .eyebrow a:hover{text-decoration:underline}.lesson-head{align-items:center}.lesson-head .eyebrow{letter-spacing:.05em}.topic-head h1,.topic-head .subtitle{margin-block-end:0}.facts-cards{grid-template-columns:repeat(auto-fit,minmax(15rem,1fr));margin-block-end:var(--s-3)}.facts-cards h3{text-transform:uppercase;letter-spacing:.05em;color:var(--c-muted);margin-block-end:var(--s-2);font-size:.8rem}.facts-cards p{margin-block-end:var(--s-2)}.hero .numbers{max-inline-size:34rem}.hero-icon>.icon-tile{margin-block-end:var(--s-4)}@media (width>=40rem){.hero-icon{column-gap:var(--s-6);grid-template-columns:1fr auto;display:grid}.hero-icon>*{grid-column:1}.hero-icon>.icon-tile{grid-area:1/2/span 6;align-self:start;margin:0}}.lesson-card{align-items:flex-start;gap:var(--s-3);display:flex}.lesson-card>div{min-inline-size:0}.lesson-card h3{margin-block-end:var(--s-1)}.lesson-card p{margin-block-end:var(--s-2)}.lesson-card>:last-child>:last-child{margin-block-end:0}a.lesson-card:hover{border-color:var(--a-border);background:var(--c-surface)}.lesson-num{background:var(--a-soft);block-size:1.9rem;inline-size:1.9rem;color:var(--a-text);font-variant-numeric:tabular-nums;border-radius:50%;flex:none;place-items:center;font-size:.9rem;font-weight:700;display:grid}.card-quiet .lesson-num{border:1px dashed var(--c-border-strong);color:var(--c-muted);background:0 0}.pager.topic .pager-title{color:var(--a-text)}.pager-topic{color:var(--a-text);font-size:.85rem}.nowrap{white-space:nowrap}.lesson-passed{color:var(--c-ok);font-weight:600}.meta .link{color:inherit;font-size:inherit}.lesson-card[data-passed] .lesson-num{color:#0000;background:var(--c-ok-bg);box-shadow:inset 0 0 0 1px var(--c-ok-border);position:relative}.lesson-card[data-passed] .lesson-num:after{content:"✓";color:var(--c-ok);place-items:center;display:grid;position:absolute;inset:0}.lesson-card[data-failed] .lesson-num{color:#0000;background:var(--c-err-bg);box-shadow:inset 0 0 0 1px var(--c-err-border);position:relative}.lesson-card[data-failed] .lesson-num:after{content:"✗";color:var(--c-err);place-items:center;display:grid;position:absolute;inset:0}.hero-progress{margin:var(--s-3) 0 0}.hero-progress[hidden]{display:none}.badge-passed{background:var(--c-ok-bg);color:var(--c-ok);font-weight:600}.badge-passed[hidden],.topic-progress[hidden]{display:none}.topic-progress{margin:var(--s-2) 0 0;color:var(--c-ok);font-size:.95rem;font-weight:600}.sr-only{clip-path:inset(50%);white-space:nowrap;block-size:1px;inline-size:1px;position:absolute;overflow:hidden}.key-facts{margin-block:var(--s-6);padding:var(--s-4) var(--s-5);background:var(--a-bg,var(--c-surface));border:1px solid var(--a-border,var(--c-border));border-inline-start:4px solid var(--a-solid,var(--c-primary));border-radius:var(--radius)}.key-facts h2{margin-block:0 var(--s-3);font-size:1.15rem}.key-facts ul{gap:var(--s-2);margin:0;padding-inline-start:1.2em;display:grid}.key-facts li>span{display:block}.key-facts li .tr{color:var(--c-muted);font-size:.95rem}@media (width>=60rem){.key-facts.two li{gap:var(--s-6);grid-template-columns:1fr 1fr;display:grid}.key-facts.two li .tr{font-size:inherit}}@media (width>=60rem) and (hover:hover){.bi.two .row:not(.li):not(.table),.bi.two .row.li,.key-facts.two li,.bi.two .row.table .merged tbody tr{border-radius:var(--radius);transition:background-color .12s,box-shadow .12s}.bi.two .row:not(.table):hover,.key-facts.two li:hover{background:var(--c-row-hover);box-shadow:0 0 0 var(--s-2) var(--c-row-hover)}.bi.two .row.table .merged tbody tr:hover{background:var(--c-row-hover)}}.dialog.support-ask{inline-size:min(100% - 2 * var(--gutter), 32rem);padding:var(--s-6) var(--s-5) var(--s-5)}.support-free{align-items:center;gap:var(--s-3);margin-block-end:var(--s-3);display:flex}.support-free-mark{background:var(--c-ok-bg);block-size:2.6rem;inline-size:2.6rem;color:var(--c-ok);box-shadow:inset 0 0 0 1px var(--c-ok-border);border-radius:50%;flex:none;place-items:center;font-size:1.4rem;font-weight:700;display:grid}.support-free h2{color:var(--c-ok);margin:0;font-size:clamp(1.5rem,4vw + .5rem,1.9rem);line-height:1.15}.support-give{align-items:center;gap:var(--s-3) var(--s-4);padding:calc(var(--s-4) + 6px) var(--s-4) var(--s-4);border-radius:var(--radius);background:linear-gradient(to bottom, #0057b7 0 3px, gold 3px 6px, var(--c-primary-soft) 6px);margin-block:var(--s-4) var(--s-3);flex-wrap:wrap;display:flex}.support-choice{align-items:center;gap:var(--s-3) var(--s-4);flex-flow:row-reverse wrap;margin-block-start:var(--s-4);display:flex}@media (width<=40rem){.support-choice{text-align:center;flex-direction:column;align-items:stretch}}.support-card h3{margin-block-start:0}.dialog-signin{align-items:stretch;gap:var(--s-2);flex-direction:column}.dialog-signin .link{align-self:center;margin-block-start:var(--s-1)}.save-progress .actions{align-items:center}.btn-google{font:inherit;border-radius:var(--radius);border:1px solid var(--c-google-border);background:var(--c-google-bg);color:var(--c-google-text);cursor:pointer;justify-content:center;align-items:center;gap:.6em;padding:.6em 1.1em;font-weight:500;line-height:1.2;display:inline-flex}.btn-google:disabled{opacity:.6;cursor:default}.btn-google.is-pending:disabled{opacity:1}.btn-google .g-logo{flex:none;block-size:1.15em;inline-size:1.15em}.google-who{align-items:center;gap:var(--s-3);margin-block-end:var(--s-3);display:flex}.google-who img{border-radius:50%;flex:none}.google-who>div{flex-direction:column;min-inline-size:0;display:flex}.google-who span{overflow-wrap:anywhere;font-size:.95rem}.attempt-head{align-items:baseline;gap:var(--s-1) var(--s-2);flex-wrap:wrap;display:flex}.badge-lesson{border:1px solid var(--c-border-strong);color:var(--c-muted);background:0 0}.badge-topic{background:var(--c-primary-soft-2);color:var(--c-primary-text);font-weight:600}.badge-full{background:var(--c-primary);color:var(--c-primary-ink);font-weight:600}.topic-test{margin:0}