:root{--blue:#025ea1;--blue-dark:#014a80;--orange:#f5a61f;--orange-dark:#e67600;--ink:#333;--muted:#666;--line:#d9e2ee;--paper:#f2f6fb;--tint:#e1e9f4;--white:#fff}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:var(--paper);font-family:Hiragino Kaku Gothic ProN,Hiragino Sans,Yu Gothic,Meiryo,sans-serif;line-height:1.8;word-break:keep-all;overflow-wrap:anywhere}a{color:inherit;text-decoration:none}a:hover{color:var(--blue)}.nb{white-space:nowrap}.shell{width:min(1120px,calc(100% - 40px));margin:auto}.site-header{background:var(--white)}.header-top{display:flex;align-items:center;justify-content:space-between;gap:20px;padding:14px 0}.brand-block p{margin:4px 0 0;font-size:13px;color:var(--muted);line-height:1.5}.brand{display:flex;align-items:center;gap:8px}.brand img{display:block;height:40px;width:auto}.brand-name{font-size:22px;font-weight:700;letter-spacing:.03em;color:var(--ink)}.header-contact{display:flex;align-items:center;gap:22px}.tel{text-align:right;line-height:1.3}.tel span{display:block;font-size:13px;color:var(--muted)}.tel a{font-size:26px;font-weight:700;letter-spacing:.03em;color:var(--blue)}.header-buttons{display:grid;grid-gap:6px;gap:6px}.header-buttons a{display:block;padding:6px 16px;background:var(--tint);color:var(--blue);font-size:13px;font-weight:700;white-space:nowrap}.header-buttons a:before{content:"›";margin-right:8px}.header-buttons a:hover{background:var(--blue);color:#fff}.main-nav{background:var(--blue)}.main-nav-inner{display:flex;align-items:stretch;justify-content:center;overflow-x:auto;white-space:nowrap}.main-nav a{display:flex;align-items:center;padding:13px 20px;color:#fff;font-size:13px;font-weight:700;letter-spacing:.06em}.main-nav a:hover{background:var(--blue-dark);color:#fff}.main-nav .is-current{background:var(--blue-dark);box-shadow:inset 0 -3px 0 var(--orange)}.main-nav .nav-contact{background:var(--orange);color:#fff}.main-nav .nav-contact:hover{background:var(--orange-dark)}.eyebrow{display:block;color:var(--blue);font-size:13px;font-weight:700;letter-spacing:.18em}.tag{padding:1px 10px;border:1px solid}.draft-label,.tag{display:inline-block;font-size:13px;font-weight:700}.draft-label{margin-left:8px;padding:1px 8px;background:var(--tint);color:var(--blue)}.button{display:inline-block;padding:12px 26px;background:var(--orange);color:#fff;font-size:14px;font-weight:700}.button:hover{background:var(--orange-dark);color:#fff}.page-title{padding:52px 0 8px}.post-card-head h2,.toc li,h1,h2,h3{text-wrap:balance}.page-title h1{margin:8px 0 12px;font-size:38px;line-height:1.3;color:var(--ink)}.page-title p{margin:0;max-width:720px;color:var(--muted);text-wrap:balance}.content{padding:28px 0 90px}.pills{display:flex;flex-wrap:wrap;gap:10px;margin-bottom:30px}.pill{padding:8px 18px;border:1px solid var(--line);border-radius:999px;background:#fff;color:var(--ink);font:inherit;font-size:14px;font-weight:700;cursor:pointer}.pill span{margin-left:4px;color:var(--muted);font-weight:400}.pill:hover{border-color:var(--blue);color:var(--blue)}.pill.is-active{background:var(--blue);border-color:var(--blue);color:#fff}.pill.is-active span{color:#cfe3f5}.card-grid{display:grid;grid-template-columns:repeat(3,1fr);grid-gap:22px;gap:22px}.post-card{display:flex;flex-direction:column;background:#fff;border:1px solid var(--line)}.post-card:hover{border-color:var(--blue);color:inherit;box-shadow:0 4px 14px rgba(2,94,161,.14)}.post-card-head{flex:1 1;min-height:210px;padding:18px 20px 22px;background:var(--blue);color:#fff}.post-card-brand{display:block;margin-bottom:26px;font-size:13px;font-weight:700;letter-spacing:.08em}.post-card-brand:before{content:"";display:inline-block;width:14px;height:2px;margin-right:8px;vertical-align:middle;background:var(--orange)}.post-card-head .tag{margin-bottom:10px;color:#fff}.post-card-head h2{margin:0;font-size:18px;line-height:1.6}.post-card-foot{display:flex;flex-wrap:wrap;align-items:center;gap:4px 14px;padding:14px 20px;color:var(--muted);font-size:13px}.post-card-foot .draft-label{margin-left:auto}.empty{padding:40px 0;color:var(--muted)}.article-main{padding-bottom:90px}.breadcrumbs{display:flex;flex-wrap:wrap;gap:8px;padding:22px 0;color:var(--muted);font-size:13px}.breadcrumbs a{color:var(--blue)}.article-layout,.breadcrumbs{max-width:820px;margin-left:auto;margin-right:auto}.article-layout article{padding:44px 48px;background:#fff;border:1px solid var(--line)}.article-header h1{margin:14px 0 10px;font-size:30px;line-height:1.5}.article-header p{margin:0;color:var(--muted);font-size:13px}.conclusion{margin:28px 0;padding:22px 26px;background:var(--paper);border-left:5px solid var(--orange)}.conclusion p{margin:8px 0 0;font-weight:700}.toc{margin:0 0 12px;padding:20px 26px;border:1px solid var(--line)}.toc strong{display:block;margin-bottom:8px;color:var(--blue)}.toc ol{margin:0;padding-left:22px}.toc li+li{margin-top:4px}.toc a:hover{text-decoration:underline}.article-section{margin-top:46px}.article-section h2,.sources h2{margin:0 0 16px;padding:12px 16px;background:var(--tint);border-left:5px solid var(--blue);font-size:22px;line-height:1.5}.article-section p,.sources li{margin:0 0 14px;text-wrap:pretty}.diagram{margin:26px 0;padding:22px 26px;background:var(--paper);border:1px solid var(--line)}.diagram figcaption{margin-bottom:14px;font-size:13px;font-weight:700}.diagram-steps{display:flex;gap:18px;margin:0;padding:0;list-style:none;counter-reset:diagram}.diagram-steps li{position:relative;flex:1 1;min-width:0;counter-increment:diagram;padding:13px 6px;background:#fff;border:1px solid var(--line);font-size:13px;text-align:center}.diagram-steps li:not(:last-child):after{content:"";position:absolute;top:50%;right:-13px;width:8px;height:8px;border-top:2px solid var(--blue);border-right:2px solid var(--blue);transform:translateY(-50%) rotate(45deg)}.diagram-steps li:before{content:counter(diagram,decimal-leading-zero);display:block;color:var(--blue);font-size:22px;font-weight:700}.faq{margin-bottom:18px}.faq h3{margin:0 0 6px;color:var(--blue);font-size:18px}.faq p{margin:0}.sources{margin-top:46px}.sources ul{margin:0;padding-left:20px}.sources a{color:var(--blue);text-decoration:underline}.office-card{margin-top:46px;padding:26px 30px;background:var(--paper);border:2px solid var(--blue)}.office-card h2{margin:6px 0;font-size:22px}.office-card p{margin:0 0 10px}.office-card .button{margin-top:6px}.cta{display:flex;align-items:center;justify-content:space-between;gap:24px;margin:36px 0;padding:26px 30px;background:var(--blue);color:#fff}.cta .eyebrow{color:#cfe3f5}.cta p{margin:6px 0 0}.cta .cta-title{font-size:20px;font-weight:700;line-height:1.6}.cta .cta-note{font-size:13px}.cta .cta-note,.cta .cta-title{text-wrap:balance}.cta .button{flex:none;white-space:nowrap}.cta .button:hover{background:var(--orange-dark)}.cta-compact{margin:28px 0;padding:20px 24px;background:var(--tint);color:var(--ink)}.cta-compact .eyebrow{color:var(--blue)}.cta-compact .cta-title{color:var(--blue-dark);font-size:17px}.not-found{padding:90px 0 130px}.not-found h1{font-weight:700}.not-found .button{margin-top:20px}footer{background:var(--blue-dark);color:#fff;padding:46px 0}.footer-inner{display:flex;align-items:flex-start;justify-content:space-between;gap:30px}.footer-inner strong{font-size:18px}.footer-inner a,.footer-inner p{color:#dbe8f5;font-size:13px}.footer-inner p{margin:8px 0 0}.footer-inner a:hover{color:#fff;text-decoration:underline}.footer-inner>div:last-child{display:flex;flex-wrap:wrap;gap:8px 24px}@media (max-width:900px){.card-grid{grid-template-columns:repeat(2,1fr)}.article-layout article{padding:34px 28px}.site-header{position:-webkit-sticky;position:sticky;top:0;z-index:50}.header-top,.main-nav{display:none}html{scroll-padding-top:76px}}@media (max-width:600px){.shell{width:min(100% - 32px,1120px)}.page-title{padding-top:36px}.page-title h1{font-size:30px}.card-grid{grid-template-columns:1fr}.post-card-head{min-height:0}.article-layout article{padding:28px 18px}.article-header h1{font-size:26px}.article-section h2,.sources h2{font-size:18px}.footer-inner{display:block}.footer-inner>div:last-child{margin-top:24px}}.article-table{margin:26px 0}.article-table figcaption{margin-bottom:10px;font-size:14px;font-weight:700}.table-scroll{overflow-x:auto;border:1px solid var(--line);background:#fff}.article-table table{width:100%;border-collapse:collapse;font-size:16px;line-height:1.6}.article-table td,.article-table th{padding:10px 14px;border-bottom:1px solid var(--line);text-align:left;vertical-align:top;word-break:keep-all;overflow-wrap:normal}.article-table thead th{background:var(--tint);color:var(--blue-dark);font-size:14px;white-space:nowrap}.article-table tbody th{background:var(--paper);font-weight:700}.article-table tbody tr:last-child td,.article-table tbody tr:last-child th{border-bottom:0}.article-section p.table-note{margin:10px 0 0;color:var(--muted);font-size:14px}@media (max-width:600px){.article-table table{font-size:14px}.article-table td,.article-table th{padding:8px 6px}.article-table thead th{font-size:13px;white-space:normal}}.article-layout article{min-width:0}.table-scroll{max-width:100%}.mobile-header{display:none;background:var(--white);border-bottom:1px solid var(--line)}.mobile-bar{display:flex;align-items:center;justify-content:space-between;gap:8px;width:min(100% - 32px,1120px);min-height:60px;margin:0 auto}.mobile-bar .brand img{height:32px}.mobile-bar .brand-name{font-size:18px}.icon-button,.mobile-actions{display:flex;align-items:center}.icon-button{flex-direction:column;justify-content:center;width:44px;height:44px;padding:0;border:0;background:none;color:var(--blue);cursor:pointer}.burger{gap:6px}.burger span{display:block;width:24px;height:2px;background:var(--ink);transition:transform .25s,opacity .25s}.burger.is-open span:first-child{transform:translateY(8px) rotate(45deg)}.burger.is-open span:nth-child(2){opacity:0}.burger.is-open span:nth-child(3){transform:translateY(-8px) rotate(-45deg)}.mobile-panel{position:absolute;top:100%;left:0;right:0;max-height:calc(100vh - 61px);max-height:calc(100dvh - 61px);overflow-y:auto;background:var(--white);border-bottom:1px solid var(--line);box-shadow:0 10px 18px rgba(0,0,0,.1)}.mobile-panel[hidden]{display:none}.mobile-panel-inner{width:min(100% - 32px,1120px);margin:0 auto;padding:4px 0 20px}.mobile-links a{display:block;padding:14px 4px;border-bottom:1px solid var(--line);font-size:16px;font-weight:700;color:var(--ink)}.mobile-links a[aria-current=page]{padding-left:14px;background:var(--paper);box-shadow:inset 3px 0 0 var(--orange);color:var(--blue)}.mobile-cta{display:grid;grid-gap:8px;gap:8px;margin-top:16px}.mobile-cta a{display:block;padding:13px 16px;background:var(--tint);color:var(--blue);font-size:15px;font-weight:700;text-align:center}.mobile-cta a.primary{background:var(--orange);color:#fff}.mobile-tel{margin-top:14px;text-align:center;font-size:13px;color:var(--muted)}.mobile-tel a{display:block;font-size:24px;font-weight:700;letter-spacing:.03em;color:var(--blue)}@media (max-width:900px){.mobile-header{display:block}}.bars{display:grid;grid-gap:10px;gap:10px}.bar-row{display:grid;grid-template-columns:minmax(0,1.5fr) minmax(0,1fr) 4.5em;align-items:center;grid-gap:12px;gap:12px;font-size:14px}.bar-track{display:block;height:12px;background:var(--tint)}.bar-fill{display:block;height:100%;background:var(--blue)}.bar-value{text-align:right;font-weight:700;white-space:nowrap}.bar-total{display:flex;align-items:baseline;justify-content:space-between;gap:12px;margin:14px 0 0;padding-top:12px;border-top:2px solid var(--blue);font-size:14px;font-weight:700}.bar-total strong{color:var(--blue);font-size:18px}.article-section p.diagram-note{margin:12px 0 0;color:var(--muted);font-size:13px}@media (max-width:600px){.bar-row{grid-template-columns:minmax(0,1fr) auto;gap:4px 12px}.bars .bar-label{grid-column:1/-1}.bar-total{flex-direction:column;align-items:flex-start;gap:2px}}.article-table figcaption,.diagram figcaption,.diagram-steps li{text-wrap:balance}.article-header h1,.article-layout article p:not(.table-note):not(.diagram-note):not(.cta-title):not(.cta-note):not(.diagram p):not(.info-box p){word-break:normal;overflow-wrap:break-word;line-break:strict}.article-header h1{text-wrap:wrap}@media (max-width:600px){.bar-total strong{font-size:16px;white-space:nowrap}.diagram-steps{flex-direction:column;gap:22px}.diagram-steps li{display:flex;align-items:center;gap:14px;padding:12px 16px;font-size:14px;text-align:left}.diagram-steps li:before{min-width:2.2em}.diagram-steps li:not(:last-child):after{top:auto;bottom:-15px;right:auto;left:50%;transform:translateX(-50%) rotate(135deg)}.cta{flex-direction:column;align-items:stretch;gap:16px;padding:22px 20px}.cta .button{text-align:center}}.compare{display:grid;grid-template-columns:repeat(auto-fit,minmax(0,1fr));grid-gap:12px;gap:12px}.compare-2{grid-template-columns:repeat(2,minmax(0,1fr))}.compare-3{grid-template-columns:repeat(3,minmax(0,1fr))}.compare-4{grid-template-columns:repeat(4,minmax(0,1fr))}.compare-card{display:flex;flex-direction:column;gap:8px;padding:16px 14px;background:#fff;border:1px solid var(--line);border-top:4px solid var(--blue)}.article-section .compare-card p{margin:0}.compare-heading{color:var(--blue);font-size:18px;font-weight:700;line-height:1.5}.compare-tag{align-self:flex-start;padding:1px 10px;background:var(--tint);color:var(--blue-dark);font-size:13px;font-weight:700}.compare-text{font-size:14px;line-height:1.7;text-wrap:pretty}.article-section .formula p{margin:0}.formula-line{display:flex;flex-wrap:wrap;align-items:center;justify-content:center;gap:8px 10px;padding:16px 12px;background:#fff;font-size:18px;font-weight:700}.formula-line,.formula-term{border:1px solid var(--line)}.formula-term{padding:4px 12px;background:var(--paper);text-align:center}.formula-result{background:var(--blue);border-color:var(--blue);color:#fff}.formula-op{color:var(--blue);font-size:22px;line-height:1}.article-section .formula .formula-examples-title{margin:14px 0 8px;font-size:13px;font-weight:700}.formula-examples{display:grid;grid-template-columns:repeat(auto-fit,minmax(120px,1fr));grid-gap:8px;gap:8px;margin:0}.formula-examples div{padding:10px 8px;background:#fff;border:1px solid var(--line);text-align:center}.formula-examples dt{font-size:13px;color:var(--muted)}.formula-examples dd{margin:2px 0 0;color:var(--blue);font-size:18px;font-weight:700;white-space:nowrap}.checklist{display:grid;grid-gap:8px;gap:8px;margin:0;padding:0;list-style:none}.checklist li{position:relative;padding:12px 14px 12px 46px;background:#fff;border:1px solid var(--line);font-size:14px;line-height:1.7}.checklist li:before{content:"";position:absolute;top:14px;left:14px;width:18px;height:18px;border:2px solid var(--blue);background:#fff}.checklist li:after{content:"";position:absolute;top:17px;left:20px;width:6px;height:10px;border-right:2px solid var(--blue);border-bottom:2px solid var(--blue);transform:rotate(45deg)}.timeline{display:flex;align-items:stretch;margin:0;padding:0;list-style:none}.timeline-item{display:flex;align-items:center;flex:1 1;min-width:0}.timeline-item:last-child{flex:0 0 auto}.timeline-point{display:flex;flex-direction:column;align-items:center;flex:none;min-width:9em;padding:12px 14px;background:#fff;border:2px solid var(--blue);text-align:center}.timeline-date{color:var(--blue);font-size:22px;line-height:1.4;white-space:nowrap}.timeline-label{font-size:13px;font-weight:700}.timeline-span{position:relative;flex:1 1 auto;min-width:6em;margin:0 4px;padding-bottom:10px;text-align:center;font-size:14px;font-weight:700;color:var(--blue-dark)}.timeline-span:after{content:"";position:absolute;left:0;right:8px;bottom:0;height:2px;background:var(--blue)}.timeline-span:before{content:"";position:absolute;right:2px;bottom:-4px;width:8px;height:8px;border-top:2px solid var(--blue);border-right:2px solid var(--blue);transform:rotate(45deg)}.info-box{margin:26px 0;padding:22px 26px;background:#fff;border:2px solid var(--blue)}.article-layout article .info-box p{margin:0}.article-layout article .info-box .info-title{margin-bottom:12px;color:var(--blue);font-size:18px;font-weight:700;line-height:1.5}.info-rows{margin:0;border-top:1px solid var(--line)}.info-row{display:grid;grid-template-columns:7em minmax(0,1fr);grid-gap:16px;gap:16px;padding:10px 0;border-bottom:1px solid var(--line);font-size:16px;line-height:1.7}.info-row dt{color:var(--blue-dark);font-weight:700}.info-row dd{margin:0}.info-tel{color:var(--blue);font-weight:700;text-decoration:underline}.article-layout article .info-box .info-note{margin-top:10px;color:var(--muted);font-size:14px}.info-actions{display:flex;flex-wrap:wrap;align-items:center;gap:12px 20px;margin-top:16px}.info-more{color:var(--blue);font-size:14px;text-decoration:underline}.conclusion+.info-box{margin-top:-12px}@media (max-width:600px){.compare,.compare-2,.compare-3,.compare-4{grid-template-columns:minmax(0,1fr)}.compare-card{padding:14px}.formula-line{font-size:16px;gap:6px 8px}.formula-examples{grid-template-columns:repeat(2,minmax(0,1fr))}.timeline,.timeline-item{flex-direction:column}.timeline-item{align-items:stretch}.timeline-point{min-width:0}.timeline-span{min-width:0;margin:0;padding:16px 0 16px 48px;text-align:left}.timeline-span:after{left:28px;right:auto;top:0;bottom:8px;width:2px;height:auto}.timeline-span:before{left:25px;right:auto;bottom:2px;transform:rotate(135deg)}.info-box{padding:18px 16px}.info-row{grid-template-columns:minmax(0,1fr);gap:2px;font-size:14px}.info-actions .button{width:100%;text-align:center}}.article-section h2,.article-section h3,.article-section li,.diagram li,.diagram p,.sources li{text-wrap:balance}