.learn-scope{--learn-accent:var(--color-brand);--learn-accent-tint:color-mix(in oklab,var(--color-brand) 9%,transparent);--learn-accent-line:color-mix(in oklab,var(--color-brand) 28%,transparent);--learn-wrong:#c00;--learn-wrong-tint:rgb(204 0 0/7%);--learn-surface:#fff;--learn-surface-sunken:#f3f5f5;--learn-page:#f7f8f8;--learn-border:rgb(17 24 28/9%);--learn-border-strong:rgb(17 24 28/16%);--learn-text:#14181b;--learn-text-dim:#5d666d;--learn-veil:rgb(243 245 245/72%);--learn-hero-fade:#fbfcfc;--learn-callout-bg:#f3f5f7;--learn-hero-grid:rgb(17 24 28/7%);--learn-header-offset:var(--site-nav-h);--learn-spine-empty:rgb(17 24 28/9%);--learn-shadow:0 1px 2px rgb(17 24 28/4%),0 14px 32px -18px rgb(17 24 28/22%);--learn-shadow-soft:0 1px 2px rgb(17 24 28/4%);font-family:-apple-system,blinkmacsystemfont,PingFang SC,Hiragino Sans GB,Microsoft YaHei,Noto Sans SC,sans-serif;color:var(--learn-text);background:var(--learn-page)}[data-theme=dark] .learn-scope{--learn-accent:var(--color-brand);--learn-accent-tint:color-mix(in oklab,var(--color-brand) 16%,transparent);--learn-accent-line:color-mix(in oklab,var(--color-brand) 36%,transparent);--learn-wrong:#ff6b6b;--learn-wrong-tint:rgb(255 107 107/10%);--learn-surface:#171a1d;--learn-surface-sunken:#1e2225;--learn-page:#101315;--learn-border:rgb(255 255 255/9%);--learn-border-strong:rgb(255 255 255/17%);--learn-text:rgb(255 255 255/88%);--learn-text-dim:rgb(255 255 255/55%);--learn-veil:rgb(30 34 37/78%);--learn-hero-fade:#14171a;--learn-callout-bg:rgb(255 255 255/5%);--learn-hero-grid:rgb(255 255 255/7%);--learn-spine-empty:rgb(255 255 255/11%);--learn-shadow:0 1px 2px rgb(0 0 0/30%),0 16px 34px -20px rgb(0 0 0/60%);--learn-shadow-soft:0 1px 2px rgb(0 0 0/30%)}.learn-num{font-family:ui-monospace,JetBrains Mono,sfmono-regular,menlo,monospace;font-variant-numeric:tabular-nums}.learn-eyebrow{margin:0;font-size:11px;font-weight:600;letter-spacing:.16em;color:var(--learn-text-dim);text-transform:uppercase}.learn-hero{position:relative;overflow:hidden;background:radial-gradient(120% 150% at 100% 0,var(--learn-accent-tint) 0,transparent 58%),linear-gradient(180deg,var(--learn-surface) 0,var(--learn-hero-fade) 100%);border-bottom:1px solid var(--learn-border-strong)}.learn-hero:before{position:absolute;background-image:linear-gradient(to right,var(--learn-hero-grid) 1px,transparent 1px),linear-gradient(to bottom,var(--learn-hero-grid) 1px,transparent 1px);background-size:32px 32px;content:"";inset:0;mask-image:linear-gradient(180deg,#000,rgb(0 0 0/45%) 55%,transparent)}.learn-hero-inner{padding-top:calc(var(--learn-header-offset) + 24px);padding-bottom:40px}@media (width >= 640px){.learn-hero-inner{padding-top:calc(var(--learn-header-offset) + 40px);padding-bottom:48px}}.learn-heat-scroll{padding-bottom:2px;overflow-x:auto}.learn-skeleton{background:var(--learn-spine-empty)!important}.learn-timeline-item{position:relative;padding-left:24px}.learn-timeline-item:before{position:absolute;top:16px;bottom:-14px;left:5px;width:2px;background:var(--learn-border);content:""}.learn-timeline-item:last-child:before{display:none}.learn-timeline-item:after{position:absolute;top:4px;left:0;width:12px;height:12px;background:var(--learn-surface);border:2px solid var(--learn-accent);border-radius:50%;content:""}.learn-heat-cell{width:11px;height:11px;background:var(--learn-spine-empty);border-radius:2px}.learn-heat-cell[data-level="1"]{background:color-mix(in oklab,var(--learn-accent) 26%,transparent)}.learn-heat-cell[data-level="2"]{background:color-mix(in oklab,var(--learn-accent) 48%,transparent)}.learn-heat-cell[data-level="3"]{background:color-mix(in oklab,var(--learn-accent) 72%,transparent)}.learn-heat-cell[data-level="4"]{background:var(--learn-accent)}.learn-heat-cell[data-today="1"]{box-shadow:0 0 0 1.5px var(--learn-accent)}.learn-node-list{padding-left:0;list-style:none}.learn-page-top{padding-top:calc(var(--learn-header-offset) + 24px)}.learn-title-mark{position:relative;padding-left:16px}.learn-title-mark:before{position:absolute;top:.18em;bottom:.18em;left:0;width:4px;background:linear-gradient(180deg,var(--learn-accent) 0,var(--learn-accent-line) 100%);border-radius:2px;content:""}.learn-hero>*{position:relative}.learn-chip{display:inline-flex;gap:5px;align-items:center;padding:3px 9px;font-size:11.5px;font-weight:500;color:var(--learn-text-dim);white-space:nowrap;border:1px solid var(--learn-border-strong);border-radius:999px}.learn-chip-accent{color:var(--learn-accent);background:var(--learn-accent-tint);border-color:var(--learn-accent-line)}.learn-chip-wrong{color:var(--learn-wrong);background:var(--learn-wrong-tint);border-color:color-mix(in oklab,var(--learn-wrong) 32%,transparent)}.learn-card-surface{background:var(--learn-surface);border:1px solid var(--learn-border);border-radius:14px;box-shadow:var(--learn-shadow-soft)}.learn-card-main{position:relative;overflow:hidden;background:var(--learn-surface);border:1px solid var(--learn-border);border-radius:18px;box-shadow:var(--learn-shadow)}.learn-prompt{padding-left:16px;border-left:3px solid var(--learn-accent)}.learn-actionbar{display:flex;flex-wrap:wrap;gap:10px;align-items:center;padding:14px 16px;background:var(--learn-surface-sunken);border-radius:14px}.learn-callout{padding:.75rem 1.25rem;background-color:var(--learn-callout-bg);border-left:.5rem solid var(--color-brand)}.learn-quote{padding:.25rem 0 .25rem 1rem;color:var(--learn-text-dim);border-left:.2rem solid var(--learn-border-strong)}.learn-spine{display:flex;flex-direction:column-reverse;gap:2px;width:4px}.learn-spine-row{flex-direction:row;width:auto;height:5px}.learn-spine-seg{flex:1 1 auto;min-height:6px;background:var(--learn-spine-empty);border-radius:2px;transition:background .32s cubic-bezier(.22,1,.36,1)}.learn-spine-row .learn-spine-seg{min-width:7px;min-height:0}.learn-spine-seg[data-on="1"]{background:color-mix(in oklab,var(--learn-accent) 32%,transparent)}.learn-spine-seg[data-on="2"]{background:color-mix(in oklab,var(--learn-accent) 54%,transparent)}.learn-spine-seg[data-on="3"]{background:color-mix(in oklab,var(--learn-accent) 76%,transparent)}.learn-spine-seg[data-on="4"]{background:var(--learn-accent)}.learn-steps{display:flex;gap:3px;align-items:center}.learn-steps-seg{width:14px;height:4px;background:var(--learn-spine-empty);border-radius:2px;transition:background .2s ease,width .2s ease}.learn-steps-seg[data-state=done]{background:var(--learn-accent)}.learn-steps-seg[data-state=current]{width:24px;background:var(--learn-accent-tint);box-shadow:inset 0 0 0 1.5px var(--learn-accent)}.learn-veil-wrap{position:relative}.learn-veil{position:absolute;inset:0;display:flex;align-items:center;justify-content:center;background:var(--learn-veil);border-radius:12px;backdrop-filter:blur(10px);box-shadow:inset 0 1px 0 rgb(255 255 255/30%),inset 0 0 0 1px var(--learn-border)}.learn-reveal{animation:learn-wipe .24s cubic-bezier(.22,1,.36,1) both}@keyframes learn-wipe{0%{clip-path:inset(0 0 100% 0)}to{clip-path:inset(0 0 0 0)}}.learn-card-enter{animation:learn-slide .16s cubic-bezier(.22,1,.36,1) both}@keyframes learn-slide{0%{opacity:0;transform:translateX(12px)}to{opacity:1;transform:translateX(0)}}.learn-btn{display:inline-flex;gap:8px;align-items:center;justify-content:center;min-height:46px;padding:0 20px;font-size:14.5px;font-weight:600;border-radius:11px;transition:transform .14s ease,opacity .14s ease,background .14s ease}.learn-btn:active{transform:translateY(1px)}.learn-btn-primary{color:#fff!important;background:var(--color-brand);box-shadow:0 8px 18px -10px color-mix(in oklab,var(--color-brand) 70%,transparent)}.learn-btn-primary:hover{color:#fff!important;opacity:.92}.learn-btn-ghost{color:var(--learn-text-dim);background:var(--learn-surface);border:1px solid var(--learn-border-strong)}.learn-btn-ghost:hover{color:var(--learn-text);background:var(--learn-surface-sunken)}.learn-btn:disabled{cursor:not-allowed;opacity:.4}.learn-grade{display:flex;flex-direction:column;gap:2px;align-items:flex-start;min-height:62px;padding:10px 14px;text-align:left;border:1px solid var(--learn-border-strong);border-radius:12px;transition:border-color .14s ease,background .14s ease}.learn-grade:hover:not(:disabled){background:var(--learn-accent-tint);border-color:var(--learn-accent-line)}.learn-scope :focus-visible{border-radius:8px;outline:2px solid var(--learn-accent);outline-offset:2px;box-shadow:0 0 0 4px var(--learn-accent-tint)}.learn-inline :where(code),.learn-prose :where(code:not(pre.hljs>code)){padding:.2em .4em;margin:auto 3px;font-family:source-code-pro,ui-monospace,sfmono-regular,menlo,monaco,consolas,monospace;font-size:.9em;color:var(--code-text-color);background-color:var(--code-bg);border-radius:5px}.learn-prose :where(p,ul,ol,pre){margin-bottom:.75rem;line-height:1.7}.learn-prose :where(ul,ol){padding-left:1.15rem;list-style:disc}.learn-prose :where(ol){list-style:decimal}.learn-prose :where(pre){padding-right:16px;padding-bottom:14px;padding-left:16px;overflow-x:auto;font-size:13px;line-height:1.75;border-radius:10px}.learn-prose :where(pre code){padding:0;margin:0;font-size:13px;background:none;border:0}.learn-digest{overflow:hidden;background:var(--learn-surface);border:1px solid var(--learn-border);border-radius:14px;box-shadow:var(--learn-shadow-soft)}.learn-digest>summary{display:flex;gap:10px;align-items:center;padding:13px 16px;font-size:13.5px;font-weight:600;color:var(--learn-text);list-style:none;cursor:pointer;transition:background .16s ease}.learn-digest>summary::-webkit-details-marker{display:none}.learn-digest>summary:hover{background:var(--learn-surface-sunken)}.learn-digest[open]>summary{border-bottom:1px solid var(--learn-border)}.learn-digest-caret{flex:none;color:var(--learn-text-dim);transition:transform .2s cubic-bezier(.22,1,.36,1)}.learn-digest[open] .learn-digest-caret{transform:rotate(90deg)}.learn-digest-list{padding:8px;margin:0;list-style:none}.learn-digest-item{position:relative;padding:11px 12px 12px;border-radius:12px;transition:background .16s ease}.learn-digest-item:hover{background:var(--learn-surface-sunken)}.learn-digest-q{padding:0;margin:0;font-size:14.5px;font-weight:600;line-height:1.7;border:0}.learn-digest-jump{display:grid;grid-template-columns:24px minmax(0,1fr) 16px;gap:0 10px;align-items:start;width:100%;padding:0;font:inherit;color:inherit;text-align:left;cursor:pointer;background:none;border:0}.learn-digest-jump:after{position:absolute;border-radius:12px;content:"";inset:0}.learn-digest-index{display:flex;align-items:center;justify-content:center;height:22px;margin-top:2px;font-family:ui-monospace,JetBrains Mono,sfmono-regular,menlo,monospace;font-size:11.5px;font-weight:600;font-variant-numeric:tabular-nums;color:var(--learn-text-dim);background:var(--learn-surface-sunken);border-radius:7px;transition:color .16s ease,background .16s ease}.learn-digest-item:hover .learn-digest-index{color:var(--learn-accent);background:var(--learn-accent-tint)}.learn-digest-go{margin-top:5px;color:var(--learn-text-dim);opacity:0;transform:translateX(-3px);transition:opacity .16s ease,transform .16s ease}.learn-digest-item:hover .learn-digest-go,.learn-digest-jump:focus-visible .learn-digest-go{color:var(--learn-accent);opacity:1;transform:none}@media (hover:none){.learn-digest-go{opacity:.45;transform:none}}.learn-digest-a{padding-left:11px;margin:7px 0 0 34px;font-size:13px;line-height:1.75;color:var(--learn-text-dim);border-left:2px solid var(--learn-border);transition:border-color .16s ease}.learn-digest-item:hover .learn-digest-a{border-left-color:var(--learn-accent-line)}.learn-digest .learn-inline :where(code){padding:.1em .35em;margin:0 2px;font-size:.88em;color:inherit;background-color:var(--learn-surface-sunken);border:1px solid var(--learn-border)}@media (width >= 640px){.learn-digest-list{padding:10px}.learn-digest-item{padding:12px 14px 13px}.learn-digest-jump{gap:0 12px}.learn-digest-a{margin-left:36px}.learn-digest-item+.learn-digest-item{margin-top:2px}}@media (prefers-reduced-motion:reduce){.learn-card-enter,.learn-reveal{animation:none}.learn-btn,.learn-digest-caret,.learn-digest-go,.learn-digest-index,.learn-grade,.learn-spine-seg{transition:none}}.learn-scroll-slim{scrollbar-width:thin;scrollbar-color:transparent transparent}.learn-scroll-slim:hover{scrollbar-color:var(--learn-border-strong) transparent}.learn-scroll-slim::-webkit-scrollbar{width:6px}.learn-scroll-slim::-webkit-scrollbar-track{background:transparent}.learn-scroll-slim::-webkit-scrollbar-thumb{background:transparent;border-radius:999px;transition:background .2s ease}.learn-scroll-slim:hover::-webkit-scrollbar-thumb{background:var(--learn-border-strong)}.learn-scroll-slim::-webkit-scrollbar-thumb:hover{background:var(--learn-text-dim)}.learn-input{background:var(--learn-surface-sunken);border:1px solid var(--learn-border)}.learn-search{border-radius:12px}:root[data-theme=dark] .learn-card-main.wi-glass,:root[data-theme=dark] .learn-card-surface.wi-glass,:root[data-theme=dark] .learn-chip.wi-glass:not(.learn-chip-accent),:root[data-theme=dark] .learn-search.wi-glass .learn-input,:root[data-theme=dark] .learn-search.wi-glass:focus-within .learn-input{border-color:transparent}.learn-veil-wrap.wi-glass{border-radius:12px}:root[data-theme=dark] .learn-btn-ghost.wi-glass,:root[data-theme=dark] .learn-card-main.wi-glass,:root[data-theme=dark] .learn-card-surface.wi-glass,:root[data-theme=dark] .learn-digest.wi-glass{border-color:transparent}