:root{--pop-ink:#15131f;--pop-bg:#ececfb;--pop-peri:#99e;--pop-peri-deep:#6b6bd6;--pop-yellow:#ffe34d;--pop-cream:#fff9b2;--pop-blue:#2337ff;--font-pop:"M PLUS Rounded 1c", "UD Digi Kyokasho NK-R", "Ubuntu", "Atkinson", sans-serif;--shadow-pop:5px 5px 0 var(--pop-ink);--shadow-pop-lg:8px 8px 0 var(--pop-ink);--shadow-pop-sm:3px 3px 0 var(--pop-ink);--accent:var(--pop-blue);--box-shadow:var(--shadow-pop)}@font-face{font-family:Atkinson;src:url(/_astro/atkinson-regular.RL0Mhkoc.woff)format("woff");font-weight:400;font-style:normal;font-display:swap}@font-face{font-family:Atkinson;src:url(/_astro/atkinson-bold.Bzqih8FG.woff)format("woff");font-weight:700;font-style:normal;font-display:swap}*{box-sizing:border-box}html,body{min-height:100%;margin:0}svg{display:block}body{background-color:var(--pop-bg);font-family:var(--font-pop);color:var(--pop-ink);word-wrap:break-word;overflow-wrap:break-word;background-image:linear-gradient(#9999eeb3 1.5px,#0000 1.5px),linear-gradient(90deg,#9999eeb3 1.5px,#0000 1.5px),linear-gradient(#9999ee40 1px,#0000 1px),linear-gradient(90deg,#9999ee40 1px,#0000 1px);background-size:100px 100px,100px 100px,20px 20px,20px 20px;font-size:16px;line-height:1.7}.sticker{border:3px solid var(--pop-ink);box-shadow:var(--shadow-pop);background:#fff;border-radius:26px}.pop-btn{font-family:var(--font-pop);cursor:pointer;border:3px solid var(--pop-ink);background:var(--pop-yellow);color:var(--pop-ink);box-shadow:var(--shadow-pop);border-radius:999px;align-items:center;gap:8px;padding:13px 26px;font-size:17px;font-weight:800;text-decoration:none;transition:transform .12s,box-shadow .12s;display:inline-flex}.pop-btn:hover{box-shadow:var(--shadow-pop-lg);transform:translate(-2px,-2px)}.pop-btn:active{box-shadow:0 0 0 var(--pop-ink);transform:translate(5px,5px)}.pop-btn.blue{background:var(--pop-blue);color:#fff}.pop-btn.peri{background:var(--pop-peri);color:var(--pop-ink)}.pop-btn.white{background:#fff}.pop-tag{font-family:var(--font-pop);border:2.5px solid var(--pop-ink);color:var(--pop-ink);box-shadow:var(--shadow-pop-sm);background:#fff;border-radius:999px;align-items:center;padding:5px 14px;font-size:14px;font-weight:800;display:inline-flex}.pop-tag.peri{background:var(--pop-peri)}.pop-tag.yellow{background:var(--pop-yellow)}.pop-tag.blue{background:var(--pop-blue);color:#fff}.pop-h1{font-family:var(--font-pop);letter-spacing:.01em;margin:0;font-size:clamp(34px,6vw,60px);font-weight:900;line-height:1.05}.pop-h2{font-family:var(--font-pop);margin:0;font-size:clamp(24px,3.4vw,34px);font-weight:900}.pop-eyebrow{font-family:var(--font-pop);letter-spacing:.14em;text-transform:uppercase;color:var(--pop-peri-deep);font-size:14px;font-weight:800}.hl{background:linear-gradient(transparent 58%, var(--pop-yellow) 58%);border-radius:3px;padding:0 4px}.pop-nav{z-index:50;background:var(--pop-peri);border-bottom:3px solid var(--pop-ink);justify-content:space-between;align-items:center;gap:16px;padding:12px clamp(16px,4vw,40px);display:flex;position:sticky;top:0}.pop-wordmark{letter-spacing:.02em;color:var(--pop-ink);white-space:nowrap;flex:1 1 0;align-items:center;gap:10px;font-size:clamp(15px,2vw,19px);font-weight:900;text-decoration:none;display:flex}.pop-wordmark img{border:2.5px solid var(--pop-ink);width:34px;height:34px;box-shadow:var(--shadow-pop-sm);background:#fff;border-radius:999px;padding:4px;transition:transform .3s cubic-bezier(.2,.8,.2,1),box-shadow .15s}.pop-wordmark:hover img{box-shadow:4px 4px 0 var(--pop-ink);transform:rotate(-12deg)scale(1.08)}.pop-wordmark .mark-wrap{align-items:center;display:flex;position:relative}.pop-wordmark .mark-wrap:after{content:"";background:var(--pop-blue);border:2px solid var(--pop-ink);border-radius:999px;width:9px;height:9px;position:absolute;top:-3px;right:-3px}.pop-navlinks{flex-wrap:wrap;gap:8px;display:flex}.pop-navlink{font-family:var(--font-pop);cursor:pointer;border:2.5px solid var(--pop-ink);color:var(--pop-ink);box-shadow:var(--shadow-pop-sm);white-space:nowrap;background:#fff;border-radius:999px;padding:7px 15px;font-size:15px;font-weight:800;text-decoration:none;transition:transform .12s,box-shadow .12s,background .12s}.pop-navlink:hover{box-shadow:4px 4px 0 var(--pop-ink);color:var(--pop-ink);transform:translate(-1px,-1px)}.pop-navlink:active{box-shadow:0 0 0 var(--pop-ink);transform:translate(3px,3px)}.pop-navlink.is-active{background:var(--pop-yellow)}.pop-social{flex:1 1 0;justify-content:flex-end;gap:8px;display:flex}.pop-social a{border:2.5px solid var(--pop-ink);width:38px;height:38px;color:var(--pop-ink);box-shadow:var(--shadow-pop-sm);background:#fff;border-radius:999px;justify-content:center;align-items:center;text-decoration:none;transition:transform .12s,box-shadow .12s;display:flex}.pop-social a:hover{box-shadow:4px 4px 0 var(--pop-ink);color:var(--pop-ink);transform:translate(-1px,-1px)}.pop-main{max-width:1080px;margin:0 auto;padding:clamp(24px,5vw,56px) clamp(16px,4vw,32px) 80px}@keyframes pop-float{0%,to{transform:translateY(0)rotate(-2deg)}50%{transform:translateY(-14px)rotate(2deg)}}@keyframes pop-spin{to{transform:rotate(360deg)}}@keyframes pop-rise{0%{opacity:0;transform:translateY(22px)}to{opacity:1;transform:translateY(0)}}@keyframes pop-pulse{0%,to{transform:scale(1)}50%{transform:scale(1.06)}}.float{animation:4.2s ease-in-out infinite pop-float}.burst{animation:18s linear infinite pop-spin}.rise{animation:.5s cubic-bezier(.2,.8,.2,1) both pop-rise}.wobble{transition:transform .15s,box-shadow .15s}.wobble:hover{box-shadow:var(--shadow-pop-lg);transform:translate(-3px,-3px)rotate(-1deg)}@media (prefers-reduced-motion:reduce){.float,.burst,.rise{animation:none}}a.cleanlink{color:var(--pop-blue);font-weight:800;text-decoration:none}a.cleanlink:hover{text-decoration:underline}h1,h2,h3,h4,h5,h6{font-family:var(--font-pop);color:var(--pop-ink);margin:0 0 .5rem;font-weight:900;line-height:1.2}h1{font-size:2.4em}h2{font-size:1.75em}h3{font-size:1.5em}h4{font-size:1.25em}h5{font-size:1.15em}strong,b{font-weight:700}a{color:var(--pop-blue)}a:hover{color:var(--pop-peri-deep)}p{margin:0 0 1em;font-size:1em}textarea{width:100%;font-size:16px}input{font-size:16px}table{width:100%}img{max-width:100%;height:auto}code{background-color:var(--pop-cream);border:1.5px solid var(--pop-ink);border-radius:4px;padding:2px 6px;font-size:.88em}pre{border:3px solid var(--pop-ink);box-shadow:var(--shadow-pop-sm);border-radius:16px;padding:1.5em;overflow-x:auto}pre>code{all:unset}blockquote{background:var(--pop-yellow);border:3px solid var(--pop-ink);box-shadow:var(--shadow-pop);border-radius:20px;margin:26px 0;padding:20px 24px;font-size:1.05em;font-weight:800;line-height:1.7}hr{border:none;border-top:3px solid var(--pop-ink);margin:24px 0}@media (width<=720px){body{font-size:16px}.pop-social{display:none}.pop-nav{gap:10px;padding:8px 14px}.pop-wordmark{gap:8px;font-size:15px}.pop-wordmark img{width:28px;height:28px;padding:3px}.pop-navlinks{gap:6px}.pop-navlink{border-width:2px;padding:5px 11px;font-size:13px}}@media (width<=480px){.pop-nav{flex-wrap:nowrap;gap:8px;padding:5px 10px}.pop-wordmark{flex:none;gap:0}.pop-wordmark span:last-child{display:none}.pop-wordmark img{border-width:2px;width:26px;height:26px;padding:2px}.pop-wordmark .mark-wrap:after{width:7px;height:7px}.pop-navlinks{-webkit-overflow-scrolling:touch;scrollbar-width:none;flex-wrap:nowrap;flex:auto;justify-content:flex-end;gap:5px;min-width:0;overflow-x:auto}.pop-navlinks::-webkit-scrollbar{display:none}.pop-navlink{flex:none;padding:4px 10px;font-size:12.5px}}.sr-only{clip:rect(1px 1px 1px 1px);clip:rect(1px, 1px, 1px, 1px);clip-path:inset(50%);white-space:nowrap;border:0;width:1px;height:1px;margin:0;padding:0;overflow:hidden;position:absolute!important}.pop-article-body{padding:28px clamp(22px,5vw,44px) 40px;font-size:18px;font-weight:600;line-height:1.9}.pop-article-body.is-math{font-family:Times New Roman,Noto Serif JP,serif;font-weight:400}mjx-container[jax=SVG]{line-height:0;display:inline-block}mjx-container[jax=SVG]>svg{display:inline-block;overflow:visible}mjx-container[jax=SVG][display=true]{text-align:center;margin:1em 0;display:block;overflow:auto hidden}