html.purpose-course{--paper:#f5f5f2;--paper-2:#e9e9e6;--paper-3:#d7d7d4;--ink:#14161c;--ink-2:#1d2028;--text:#23242b;--text-2:#51525c;--muted:#777984;--gutter:clamp(20px,4vw,60px)}
.purpose-course .page>.frame{max-width:1520px;margin:auto}.purpose-course .page.in>.frame{animation:fn-page-in .32s var(--ease) both}.purpose-course.still .page.in>.frame{animation:none}.purpose-course [data-theme=codex]{--mark:#ffe270}.purpose-course .page.t-codex{background:#323d77}.purpose-course .fc .t,.purpose-course .fi .t{letter-spacing:-.025em}.purpose-course .page .head{margin-bottom:0}.purpose-course .t-paper .note{color:#6c6d77}.purpose-course .fc-lines{max-width:1050px}.purpose-course .fc-lines li{border-radius:0}.purpose-course .fn-bridge{display:grid;grid-template-columns:170px 1fr;align-items:center;gap:65px;max-width:1130px;margin:auto}.fn-bridge-line{display:flex;flex-direction:column;align-items:center;gap:20px;height:360px;color:#e7bb65}.fn-bridge-line>span{font:400 6.5rem/1 var(--mono);letter-spacing:-.1em}.fn-bridge-line i{width:1px;flex:1;background:#5e574d}.fn-bridge-line b{font-size:2rem;font-weight:400}.fn-bridge h1{font-size:clamp(2.2rem,4.1vw,4.5rem);line-height:1.3;letter-spacing:-.035em;max-width:900px;margin:22px 0}.fn-bridge-text{font-size:1.2rem;line-height:1.85;max-width:790px;color:#b8bbc4}.fn-bridge button{display:flex;justify-content:space-between;gap:80px;align-items:center;margin-top:36px;border-top:1px solid #464953;padding-top:20px;text-align:left;font-size:1rem}.fn-bridge button span{color:#e7bb65;font-size:1.5rem}.purpose-course #path-toggle{opacity:1;border:1px solid var(--line);border-radius:6px}.purpose-course .toc-block button .fn-branch-label{font-size:10px;margin-left:auto;color:#777}.purpose-course .branch-return{display:none}.purpose-course .page:not([hidden]) .branch-return{display:inline-flex;align-self:start;margin:0 0 20px;font-size:.85rem;color:var(--muted);border-bottom:1px solid currentColor}.purpose-course .pager #next strong{max-width:260px}.purpose-course #lesson-field{opacity:.35}.purpose-course body[data-theme=paper] #lesson-field{opacity:0}
@keyframes fn-page-in{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:translateY(0)}}
html.purpose-course::view-transition-old(stage){animation:fn-out .2s ease both}html.purpose-course::view-transition-new(stage){animation:fn-in .32s ease both}@keyframes fn-out{to{opacity:0;transform:translateX(calc(var(--dir,1)*-16px))}}@keyframes fn-in{from{opacity:0;transform:translateX(calc(var(--dir,1)*24px))}}
@media(max-width:900px){.purpose-course .fn-bridge{grid-template-columns:85px 1fr;gap:26px}.fn-bridge-line{height:300px}.fn-bridge-line>span{font-size:4rem}.fn-bridge h1{font-size:2.5rem}.fn-bridge-text{font-size:1.1rem}}
@media(max-width:600px){.purpose-course .fn-bridge{display:block}.fn-bridge-line{height:auto;flex-direction:row;justify-content:start;margin-bottom:40px}.fn-bridge-line>span{font-size:3rem}.fn-bridge-line i{height:1px;width:auto;flex:1}.fn-bridge h1{font-size:2rem}.fn-bridge-text{font-size:1rem}.fn-bridge button{gap:25px;font-size:.95rem}.purpose-course #path-toggle{padding:0 8px;font-size:.7rem}.purpose-course .brand span{display:none}}
@media(prefers-reduced-motion:reduce){.purpose-course .page.in>.frame{animation:none}}
.purpose-course .page>.frame>.branch-return{flex:0 0 auto}.purpose-course .topbar{background:var(--paper)}.purpose-course body[data-theme=ink] .topbar{background:var(--ink)}.purpose-course body[data-theme=codex] .topbar{background:#323d77}.purpose-course body[data-theme=sage] .topbar{background:#e7ebe3}.purpose-course .page{padding-bottom:calc(var(--bottom) + 42px)}