:root{--navy:#0D1B3D;--navy-deep:#122B4E;--cyan:#1BB5D9;--cyan-dark:#0E9CBA;--light-cyan:#E6F7FC;--amber:#F5A623;--amber-text:#9A6A12;--ink:#1A2433;--gray:#5A6678;--line:#DDE4EE;--panel:#F5F8FC;--paper:#FBF9F4;--warn-bg:#FFF4E5;--warn-fg:#8B4513;--danger-bg:#FDECEA;--danger-fg:#9F1B1B;--success:#1E9E6A}*{box-sizing:border-box}body{margin:0;background:var(--paper);color:var(--ink);font-family:Noto Sans JP,Hiragino Kaku Gothic ProN,Meiryo,sans-serif;line-height:1.95;font-size:17px;-webkit-font-smoothing:antialiased}a{color:var(--cyan-dark)}.container{max-width:900px;margin:0 auto;padding:28px 20px 72px}.site-head{position:sticky;top:0;z-index:30;display:flex;gap:18px;align-items:center;justify-content:space-between;padding:12px 22px;background:#fbf9f4db;backdrop-filter:blur(8px);border-bottom:1px solid var(--line);flex-wrap:wrap}.site-head .brand{display:flex;flex-direction:column;line-height:1.1;text-decoration:none}.site-head .brand b{font-family:Zen Kaku Gothic New;font-weight:900;color:var(--navy);font-size:1.18rem;letter-spacing:.04em}.site-head .brand small{font-family:Shippori Mincho B1;color:var(--amber-text);font-size:.62rem;letter-spacing:.18em;margin-top:2px}.site-head nav{display:flex;gap:18px;align-items:center;flex-wrap:wrap}.site-head nav a.nlink{color:var(--ink);text-decoration:none;font-size:.9rem;font-weight:500}.site-head nav a.nlink:hover{color:var(--cyan-dark)}.site-head nav a.cta{background:var(--amber);color:var(--navy);font-weight:700;padding:8px 16px;border-radius:999px;font-size:.86rem;text-decoration:none}.site-foot{border-top:1px solid var(--line);padding:24px 18px;font-size:.8rem;color:var(--gray);text-align:center;background:#fff}article{max-width:760px;margin:0 auto;counter-reset:sec}.breadcrumb{font-family:Shippori Mincho B1;font-size:.78rem;color:var(--gray);margin-bottom:14px;letter-spacing:.02em}.breadcrumb a{color:var(--gray)}.eyebrow{font-family:Shippori Mincho B1;font-weight:700;color:var(--amber-text);font-size:.82rem;letter-spacing:.14em}.eyebrow:before{content:"―― ";color:var(--amber)}article h1{font-family:Zen Kaku Gothic New;font-weight:900;color:var(--navy);font-size:clamp(1.6rem,4.6vw,2.4rem);line-height:1.4;margin:.35em 0 .5em;letter-spacing:.01em}.art-meta{font-size:.8rem;color:var(--gray);border-top:1px solid var(--line);border-bottom:1px solid var(--line);padding:9px 0;margin:0 0 8px;display:flex;gap:18px;flex-wrap:wrap}.art-meta b{color:var(--navy);font-weight:700}.lead{position:relative;background:#fff;border:1px solid var(--line);border-left:6px solid var(--cyan);border-radius:12px;padding:18px 22px;margin:24px 0;box-shadow:0 10px 30px -22px #0d1b3d80}.lead .tag{font-family:Shippori Mincho B1;font-weight:800;color:var(--navy);font-size:.92rem;display:flex;align-items:center;gap:9px;margin-bottom:8px}.lead .tag i{font-style:normal;background:var(--navy);color:#fff;font-size:.66rem;font-weight:700;font-family:Noto Sans JP;padding:3px 9px;border-radius:6px;letter-spacing:.08em}.lead p{margin:0;font-size:1.02rem;font-weight:500;color:#26303f}.toc{background:var(--panel);border:1px solid var(--line);border-radius:12px;padding:16px 22px;margin:24px 0}.toc h4{font-family:Zen Kaku Gothic New;font-weight:700;color:var(--navy);margin:0 0 8px;font-size:.98rem}.toc ol{margin:0;padding:0;list-style:none;counter-reset:t;columns:2;column-gap:26px}.toc li{counter-increment:t;font-size:.88rem;padding:5px 0;break-inside:avoid}.toc li:before{content:counter(t,decimal-leading-zero);font-family:Shippori Mincho B1;font-weight:700;color:var(--cyan-dark);margin-right:9px}.toc a{color:var(--ink);text-decoration:none}.toc a:hover{color:var(--cyan-dark);text-decoration:underline}article h2{font-family:Zen Kaku Gothic New;font-weight:800;color:var(--navy);font-size:clamp(1.24rem,3.2vw,1.6rem);line-height:1.5;margin:2.4em 0 .7em}article>h2{counter-increment:sec;padding-top:.7em;border-top:1px solid var(--line)}article>h2:before{content:counter(sec,decimal-leading-zero);display:block;font-family:Shippori Mincho B1;font-weight:700;color:var(--amber-text);font-size:.82rem;letter-spacing:.1em;margin-bottom:.25em}article h3{font-family:Zen Kaku Gothic New;font-weight:700;color:var(--navy);font-size:1.1rem;margin:1.8em 0 .5em;padding-left:14px;border-left:4px solid var(--cyan)}article p{margin:1.05em 0}article strong{color:var(--navy);font-weight:700}article blockquote{background:var(--light-cyan);border-left:4px solid var(--cyan);border-radius:0 10px 10px 0;padding:12px 18px;margin:18px 0;font-size:.93rem;color:#27424b}article blockquote p{margin:.3em 0}.note{background:var(--light-cyan);border-left:4px solid var(--cyan);border-radius:0 10px 10px 0;padding:13px 18px;margin:18px 0;font-size:.93rem}.note.warn{background:var(--warn-bg);border-color:var(--amber);color:#5c4316}.note.alert{background:var(--danger-bg);border-color:var(--danger-fg);color:#7c1d1d}.note.muted{background:#f3f4f6;border-color:#aab2c0;color:#4b5563;font-size:.84rem}.note .nlab{font-weight:700;font-size:.74rem;letter-spacing:.06em;margin-right:8px}.trap{background:linear-gradient(180deg,#fffaf1,#fff);border:1px solid #f0dcbf;border-left:5px solid var(--amber);border-radius:12px;padding:6px 22px 16px;margin:20px 0}.trap .ttag{display:inline-block;background:var(--amber);color:var(--navy);font-weight:700;font-size:.72rem;padding:3px 11px;border-radius:0 0 8px 8px;letter-spacing:.06em}.trap h3{border:0;padding:0;margin:.7em 0 .4em;color:var(--warn-fg)}.case{background:#fff;border:1px solid var(--line);border-left:5px solid var(--cyan-dark);border-radius:12px;padding:16px 22px;margin:20px 0}.case .ctag{font-family:Shippori Mincho B1;font-weight:700;color:var(--cyan-dark);font-size:.8rem;letter-spacing:.06em}.formula{background:var(--navy);color:#fff;border-radius:12px;padding:20px;margin:22px 0;text-align:center}.formula .f{font-family:Shippori Mincho B1;font-weight:700;font-size:1.08rem}.formula .ex{margin-top:10px;font-size:.86rem;color:var(--light-cyan)}.formula .ex b{color:var(--amber)}article table{display:block;width:max-content;max-width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch;border-collapse:collapse;margin:20px 0;font-size:.9rem;border:1px solid var(--line);border-radius:12px}article th,article td{border-top:1px solid var(--line);padding:10px 13px;text-align:left;vertical-align:top}article thead th{background:var(--navy);color:#fff;font-family:Zen Kaku Gothic New;font-weight:700;font-size:.86rem;border-top:0}article tbody tr:nth-child(2n){background:#fbfaf6}article tbody td:first-child{font-weight:700;color:var(--navy)}article pre:not(.mermaid){background:#0f172a;color:#e2e8f0;padding:14px 16px;border-radius:10px;overflow:auto;font-size:.82rem;line-height:1.6}article :not(pre)>code{background:var(--panel);padding:1px 5px;border-radius:4px;font-size:.88em}pre.mermaid{background:none;border:0;padding:0;margin:24px auto;text-align:center;overflow-x:auto;-webkit-overflow-scrolling:touch;line-height:1.2;max-width:100%}pre.mermaid svg{display:block;margin:0 auto;height:auto}article figure{margin:26px auto;max-width:560px}article figure svg{width:100%;height:auto;display:block}article figure figcaption{font-family:Shippori Mincho B1;font-size:.78rem;color:var(--gray);text-align:center;margin-top:10px}article figure.svg-fig{max-width:100%;overflow-x:auto;-webkit-overflow-scrolling:touch}article figure.svg-fig svg{max-width:700px;margin:0 auto}@media(max-width:640px){article figure.svg-fig svg{width:auto;min-width:600px}}.faq{margin-top:48px}.faq h2{border-top:2px solid var(--navy);padding-top:.7em}.faq details{border-bottom:1px solid var(--line);padding:4px 0}.faq summary{font-family:Zen Kaku Gothic New;font-weight:700;color:var(--navy);cursor:pointer;list-style:none;position:relative;padding:13px 30px 13px 4px;font-size:.98rem}.faq summary:after{content:"+";position:absolute;right:6px;top:11px;font-size:1.3rem;color:var(--cyan-dark)}.faq details[open] summary:after{content:"–"}.faq details[open] summary{color:var(--cyan-dark)}.faq details>p{padding:0 4px 14px;font-size:.93rem;color:#37414f;margin:0}.related{margin-top:40px;background:var(--panel);border:1px solid var(--line);border-radius:14px;padding:20px 24px}.related h2{font-family:Zen Kaku Gothic New;font-size:1.05rem;color:var(--navy);margin:0 0 8px;border:0;padding:0;counter-increment:none}.related h2:before{content:none}.related ul{margin:0;padding:0;list-style:none}.related li{padding:7px 0 7px 22px;position:relative;border-bottom:1px dashed var(--line)}.related li:before{content:"→";position:absolute;left:0;color:var(--cyan-dark);font-weight:700}.related a{color:var(--cyan-dark);text-decoration:none}.cta-box{margin-top:34px;background:linear-gradient(135deg,var(--navy),var(--navy-deep));color:#fff;border-radius:16px;padding:30px 26px;text-align:center;position:relative;overflow:hidden}.cta-box:after{content:"";position:absolute;right:-40px;top:-40px;width:160px;height:160px;border-radius:50%;background:radial-gradient(circle,rgba(27,181,217,.35),transparent 70%)}.cta-box strong{display:block;font-family:Zen Kaku Gothic New;font-weight:800;font-size:1.25rem;color:#fff;margin-bottom:6px}.cta-box a{display:inline-block;margin-top:14px;background:var(--amber);color:var(--navy);font-weight:800;font-size:1.02rem;padding:13px 30px;border-radius:999px;text-decoration:none;box-shadow:0 12px 26px -10px #f5a62399}@media(max-width:640px){body{font-size:16px}.site-head{padding:11px 15px}.site-head nav a.nlink{display:none}.container{padding:22px 16px 56px}.toc ol{columns:1}}