:root{--color-bg: #ffffff;--color-surface: #ffffff;--color-text: #1a1520;--color-muted: #6b6570;--color-border: #e8e4df;--color-link: #1a1520;--color-primary: #1a1520;--color-primary-dark: #0d0a10;--color-secondary: #3d6b59;--color-accent: #b8860b;--color-accent-dark: #8f6608;--color-ink: #1a1520;--color-sale: #c45c3e;--color-sale-bg: rgba(196, 92, 62, .08);--color-kindle: #f7941d;--color-kindle-bg: rgba(247, 148, 29, .1);--color-cat-kindle: #c07c2e;--color-cat-tips: #3d6b59;--color-cat-deals: #c45c3e;--color-cat-app: #4a6fa5;--color-cat-manga: #9b4dca;--shadow-sm: none;--shadow-md: none;--radius-sm: 3px;--radius-md: 4px;--radius-lg: 6px;--radius-full: 999px;--font-sans: YakuHanJP, "Roboto", "Noto Sans JP", sans-serif;--font-mono: "SF Mono", "Menlo", "Consolas", monospace;--max-width: 720px;--max-width-wide: 1200px;--space-xs: .5rem;--space-sm: 1rem;--space-md: 1.5rem;--space-lg: 2.5rem;--space-xl: 4rem;--line-height: 1.9;--line-height-heading: 1.4;--site-header-offset: 4.75rem}*,*:before,*:after{box-sizing:border-box}html{font-size:16px;-webkit-text-size-adjust:100%;scroll-behavior:smooth}body{margin:0;font-family:var(--font-sans);font-size:1.0625rem;font-weight:500;line-height:var(--line-height);color:var(--color-text);background:var(--color-bg);-webkit-font-smoothing:antialiased}img{max-width:100%;height:auto;display:block}a{color:var(--color-link);text-decoration:underline;text-decoration-thickness:2px;text-underline-offset:6px;font-weight:700;transition:opacity .15s ease}a:hover{opacity:.75}h1,h2,h3,h4{line-height:var(--line-height-heading);font-weight:800;color:var(--color-text)}h1{font-size:1.875rem;margin:0 0 var(--space-md)}h2{font-size:1.5em;font-weight:900;letter-spacing:.04em;margin:var(--space-lg) 0 var(--space-sm)}h3{font-size:1.2rem;margin:var(--space-md) 0 var(--space-xs);font-weight:800}p{margin:0 0 var(--space-sm)}ul,ol{margin:0 0 var(--space-sm);padding-left:1.5rem}li{margin-bottom:.4rem}.container{width:100%;max-width:var(--max-width-wide);margin:0 auto;padding:0 var(--space-md)}.container--narrow{max-width:var(--max-width)}.container--home{max-width:var(--max-width-wide)}.site-header{background:#1a1520;color:#fff;position:sticky;top:0;z-index:50}.site-header__inner{display:flex;align-items:center;justify-content:space-between;gap:var(--space-sm);padding-top:.75rem;padding-bottom:.75rem}.site-brand{display:inline-flex;align-items:center;gap:.35rem;flex-shrink:0;text-decoration:none;color:#fff}.site-brand:hover{opacity:.8;text-decoration:none}.site-brand__text{font-size:1.6rem;font-weight:900;letter-spacing:.1em;line-height:1}.site-brand__mark{width:2.75rem;height:2.75rem;object-fit:contain;object-position:center;filter:invert(1);flex-shrink:0;margin:0;transform:translateY(-.1em)}.site-nav{display:flex;align-items:center;flex-shrink:0;margin:0;padding:0}.site-nav-control{display:inline-flex;align-items:center;font-size:.875rem;font-weight:700;color:#fff;text-decoration:none;white-space:nowrap}.site-nav-control:hover{color:var(--color-accent);text-decoration:none;opacity:1}.site-footer{background:var(--color-bg);border-top:1px solid var(--color-border);margin-top:var(--space-xl);padding:var(--space-lg) 0;font-size:.875rem;color:var(--color-muted)}.site-footer a{color:var(--color-text)}.site-footer__nav{display:flex;flex-wrap:wrap;gap:.35rem var(--space-sm);list-style:none;margin:0 0 var(--space-md);padding:0}.site-footer__nav a{text-decoration:none;font-weight:700;padding:.35rem .75rem;border-radius:var(--radius-full);background:var(--color-bg)}.site-footer__nav a:hover{background:var(--color-text);color:#fff;text-decoration:none;opacity:1}.affiliate-notice{font-size:.8125rem;line-height:1.65;margin-top:var(--space-md);padding-top:var(--space-sm);border-top:1px dashed var(--color-border);color:var(--color-muted)}.page-title{font-size:1.625rem;margin:var(--space-xl) 0 var(--space-md);padding:.5rem 0;display:block;position:relative}.page-title:after{content:"";display:block;width:3rem;height:4px;background:var(--color-accent);border-radius:var(--radius-full);margin-top:.35rem}.page-desc{color:var(--color-muted);margin:-.5rem 0 var(--space-md)}.sitemap-page{padding-bottom:var(--space-xl)}.sitemap-section{margin-bottom:var(--space-lg)}.sitemap-section h2{font-size:1.125rem;margin:0 0 .75rem;padding-bottom:.35rem;border-bottom:1px solid var(--color-border)}.sitemap-list{list-style:none;margin:0;padding:0}.sitemap-list li{display:flex;flex-wrap:wrap;align-items:baseline;gap:.5rem 1rem;padding:.45rem 0;border-bottom:1px solid var(--color-border)}.sitemap-list li:last-child{border-bottom:none}.sitemap-list__date{font-size:.8125rem;color:var(--color-muted)}.sitemap-xml{margin-top:var(--space-lg);font-size:.875rem;color:var(--color-muted)}.layout-with-sidebar{display:grid;grid-template-columns:minmax(0,1fr) 280px;gap:var(--space-lg);align-items:stretch}.layout-with-sidebar__main,.sidebar{min-width:0}.sidebar__inner{display:flex;flex-direction:column;gap:var(--space-md)}main{padding:var(--space-md) 0 var(--space-xl);min-height:50vh}.category-badge{display:inline-block;font-size:.7rem;font-weight:800;padding:.2rem .55rem;border-radius:var(--radius-sm);border:1px solid currentColor}.category-badge--kindle{background:#c07c2e1a;color:var(--color-cat-kindle)}.category-badge--tips{background:#3d6b591a;color:var(--color-cat-tips)}.category-badge--deals{background:var(--color-sale-bg);color:var(--color-cat-deals)}.category-badge--app{background:#4a6fa51a;color:var(--color-cat-app)}.category-badge--manga{background:#9b4dca1a;color:var(--color-cat-manga)}.home-layout{display:grid;grid-template-columns:minmax(0,1fr) 300px;gap:var(--space-lg);align-items:start;padding:var(--space-md) 0 var(--space-xl)}.home-layout__main{min-width:0}.home-section{margin-bottom:var(--space-xl)}.home-section__head{margin-bottom:var(--space-md);padding-bottom:.5rem;border-bottom:2px solid var(--color-text)}.home-section__title{font-size:1.5rem;font-weight:900;letter-spacing:.15em;margin:0;text-transform:uppercase}.home-section__subtitle{font-size:.8125rem;color:var(--color-muted);margin:.25rem 0 0;font-weight:700}.home-section__footer{display:flex;justify-content:flex-end;margin:var(--space-md) 0 0}.home-section__more{font-size:.8125rem;font-weight:900;letter-spacing:.1em;text-decoration:none;padding:.35rem .75rem;border:1px solid var(--color-text)}.home-section__more:hover{background:var(--color-text);color:#fff;opacity:1}.topic-list{list-style:none;margin:0;padding:0;display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:var(--space-md)}.topic-card{padding:var(--space-md);border:1px solid var(--color-border);border-radius:var(--radius-md);background:var(--color-surface)}.topic-card__badge{margin-bottom:.5rem}.topic-card__title{font-size:1rem;font-weight:800;margin:0 0 .5rem;line-height:1.45}.topic-card__desc{font-size:.875rem;color:var(--color-muted);margin:0;line-height:1.65}.topic-card__status{display:inline-block;margin-top:.65rem;font-size:.75rem;font-weight:800;color:var(--color-muted);letter-spacing:.05em}.home-sidebar{position:sticky;top:var(--site-header-offset);align-self:start;width:100%;max-height:calc(100vh - var(--site-header-offset) - var(--space-md));overflow-y:auto;overscroll-behavior:contain;scrollbar-gutter:stable;z-index:10;display:flex;flex-direction:column;gap:var(--space-md)}.sidebar-box{border:1px solid rgba(26,21,32,.1);border-radius:.75rem;padding:1rem;background:linear-gradient(180deg,#fff,#faf8f5)}.sidebar-box__brand{display:flex;flex-direction:column;align-items:center;gap:.55rem;margin-bottom:.75rem;text-align:center}.sidebar-box__mark-wrap{display:flex;align-items:center;justify-content:center;width:4.25rem;height:4.25rem;border:2px solid rgba(26,21,32,.18);border-radius:50%;background:#fff}.sidebar-box__mark{width:2.65rem;height:2.65rem;object-fit:contain;flex-shrink:0}.sidebar-box__title{font-size:1.125rem;font-weight:900;letter-spacing:.1em;margin:0 0 .65rem;text-transform:uppercase;padding-bottom:.45rem;border-bottom:2px solid var(--color-text);line-height:1.2}.sidebar-box__title--brand{margin:0;padding:0;border-bottom:none;text-transform:none;font-size:1.05rem;letter-spacing:.08em}.sidebar-box__text{margin:0;font-size:.8125rem;font-weight:500;line-height:1.75;color:var(--color-text)}.sidebar-box__text a{font-weight:700;color:inherit;text-decoration:underline;text-decoration-thickness:1px;text-underline-offset:.18em}.sidebar-box__text a:hover{opacity:.72}.sidebar-box__list{list-style:none;margin:0;padding:0}.sidebar-box__item{padding:.5rem 0;border-top:1px solid rgba(26,21,32,.08);font-size:.875rem;font-weight:700;line-height:1.5}.sidebar-box__link{display:block;text-decoration:none;color:inherit;transition:opacity .15s ease}.sidebar-box__link:hover{opacity:.72;text-decoration:none}.sidebar-box__link:focus-visible{outline:2px solid var(--color-text);outline-offset:2px;border-radius:var(--radius-sm)}.sidebar-box__link-name{display:flex;align-items:center;gap:.35rem;font-weight:800;line-height:1.4}.sidebar-box__link-name:after{content:"↗";font-size:.75rem;font-weight:700;color:var(--color-muted);line-height:1}.sidebar-box__link-desc{display:block;margin-top:.2rem;font-size:.75rem;font-weight:500;color:var(--color-muted);line-height:1.45}.sidebar-box__item:first-child{border-top:none;padding-top:.2rem}.coming-soon-notice{text-align:center;padding:var(--space-xl) var(--space-md);border:2px dashed var(--color-border);border-radius:var(--radius-md);color:var(--color-muted)}.coming-soon-notice__title{font-size:1.125rem;font-weight:900;margin:0 0 .5rem;color:var(--color-text)}.coming-soon-notice__desc{font-size:.9375rem;margin:0}@media(min-width:961px){.layout-with-sidebar__main,.sidebar{padding-top:var(--space-lg)}.layout-with-sidebar__main .article-header,.layout-with-sidebar__main .page-title,.layout-with-sidebar__main>section:first-child,.home-layout__main .article-header{margin-top:0}.sidebar__inner{position:sticky;top:var(--site-header-offset);max-height:calc(100vh - var(--site-header-offset) - var(--space-md));overflow-y:auto;overscroll-behavior:contain;scrollbar-gutter:stable;z-index:10}}@media(max-width:960px){.layout-with-sidebar{grid-template-columns:1fr}.sidebar{display:none}.home-layout,.topic-list{grid-template-columns:1fr}}@media(max-width:640px){.site-brand__text{font-size:1.25rem}.site-brand__mark{width:2.35rem;height:2.35rem;transform:translateY(-.1em)}}.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}.post-list{display:flex;flex-direction:column;gap:0}.post-card{display:grid;grid-template-columns:13rem minmax(0,1fr);gap:var(--space-md);align-items:start;border-bottom:1px solid var(--color-border);padding:var(--space-md) 0;text-decoration:none;color:inherit}.post-card:hover{color:inherit;text-decoration:none;opacity:1}.post-card:hover .post-card__title{color:var(--color-accent)}.post-card__thumb img{width:100%;aspect-ratio:16 / 10;object-fit:cover;border-radius:var(--radius-sm);border:1px solid var(--color-border)}.post-card__thumb-ph{aspect-ratio:16 / 10;display:flex;align-items:center;justify-content:center;border-radius:var(--radius-sm);font-size:.875rem;font-weight:800;border:1px solid var(--color-border)}.post-card__thumb-ph--manga{background:#9b4dca14;color:var(--color-cat-manga)}.post-card__thumb-ph--deals{background:var(--color-sale-bg);color:var(--color-cat-deals)}.post-card__title{font-size:1.1875rem;font-weight:800;margin:.35rem 0 .5rem;line-height:1.45;transition:color .15s ease}.post-card__meta{font-size:.8125rem;margin:0;display:flex;flex-wrap:wrap;align-items:center;gap:.35rem;color:var(--color-muted)}.post-date{display:inline-flex;align-items:center;gap:.35rem}.new-badge{display:inline-block;font-size:.6875rem;font-weight:800;color:var(--color-sale);letter-spacing:.06em;line-height:1}.post-card__desc{font-size:.9375rem;margin:.5rem 0 0;color:var(--color-muted);display:-webkit-box;-webkit-line-clamp:2;-webkit-box-orient:vertical;overflow:hidden}.post-list-footer{display:flex;justify-content:flex-end;margin-top:var(--space-lg);padding-top:var(--space-md)}.text-link-arrow{font-weight:800;text-decoration:none}.sale-badge{display:inline-block;font-size:.7rem;font-weight:800;padding:.2rem .55rem;border-radius:var(--radius-sm)}.sale-badge--sale{background:var(--color-sale-bg);color:var(--color-sale);border:1px solid var(--color-sale)}.sale-badge--prime{background:var(--color-kindle-bg);color:var(--color-kindle);border:1px solid var(--color-kindle)}.article-header{margin-top:var(--space-lg);margin-bottom:var(--space-lg);padding:var(--space-lg) 0 var(--space-md);border-bottom:1px solid var(--color-border)}.article-header__meta{font-size:.875rem;margin:0 0 var(--space-sm);display:flex;flex-wrap:wrap;align-items:center;gap:.35rem;color:var(--color-muted)}.article-header h1{font-size:1.625rem;margin-top:var(--space-sm);margin-bottom:.5rem}.article-header__disclosure{font-size:.8125rem;line-height:1.5;margin:.25rem 0 0;text-align:right;color:#000;font-weight:600}.article-intro{margin:0 0 var(--space-md)}.article-intro p:last-child{margin-bottom:0}.article-lead{margin:0 0 var(--space-lg)}.article-lead p:last-child{margin-bottom:0}.toc{background:var(--color-surface);border:2px solid var(--color-border);border-radius:var(--radius-md);padding:var(--space-sm) var(--space-md);margin:0 0 var(--space-lg);font-size:.9375rem}.toc__title{font-size:.875rem;font-weight:800;margin:0 0 var(--space-xs);color:var(--color-primary)}.toc__list,.toc__sublist{margin:0;padding-left:1.25rem}.toc a{text-decoration:none;color:var(--color-text)}.toc a:hover{text-decoration:underline}.prose{max-width:var(--max-width)}.prose strong{font-weight:800}.prose table{width:100%;border-collapse:collapse;margin:0 0 var(--space-md);font-size:.9375rem;border:1px solid var(--color-border)}.prose th,.prose td{border:1px solid var(--color-border);padding:.65rem .9rem;text-align:left;vertical-align:top}.prose thead th{background:var(--color-secondary);color:#fff}.prose .amazon-product-embed{margin:var(--space-md) 0 var(--space-lg)}.share-buttons{display:flex;flex-wrap:wrap;gap:.4rem;margin:var(--space-md) 0;padding:var(--space-sm) 0;border-top:2px dashed var(--color-border);border-bottom:2px dashed var(--color-border)}.share-buttons a{font-size:.8125rem;font-weight:700;text-decoration:none;padding:.4rem .85rem;border-radius:var(--radius-full);background:var(--color-surface);border:1px solid var(--color-border)}.related-posts{margin-top:var(--space-xl);padding:var(--space-md);border:1px solid var(--color-border);border-radius:var(--radius-lg)}.related-posts h2{font-size:1.125rem;margin-top:0}.related-posts ul{list-style:none;padding:0;margin:0}.related-posts li{margin-bottom:.6rem}.amazon-product-cards{margin:var(--space-md) 0 var(--space-lg)}.amazon-product-cards__heading{font-size:1.0625rem;font-weight:800;margin:0 0 var(--space-sm)}.amazon-product-cards--covers{margin-top:var(--space-lg)}.amazon-product-cards--covers .amazon-product-cards__list{display:grid;grid-template-columns:repeat(5,minmax(0,1fr));gap:var(--space-sm)}.amazon-product-cards__list{list-style:none;margin:0;padding:0}.amazon-product-card__link{display:grid;grid-template-columns:112px 1fr;gap:var(--space-sm);align-items:start;padding:var(--space-sm);border-radius:var(--radius-sm);border:2px solid rgba(26,21,32,.15);text-decoration:none;color:var(--color-text)}.amazon-product-card__link:hover{border-color:var(--color-text);text-decoration:none;opacity:1}.amazon-product-card__image-wrap{display:flex;align-items:center;justify-content:center;background:#fff;border:1px solid var(--color-border);padding:.35rem}.amazon-product-card__image-wrap img{max-height:96px;width:auto;object-fit:contain}.amazon-product-card__label{font-size:.75rem;font-weight:700;color:var(--color-muted);margin:0 0 .25rem}.amazon-product-card__badges{display:flex;flex-wrap:wrap;gap:.35rem;margin-bottom:.35rem}.amazon-product-card__title{font-size:.9375rem;font-weight:700;line-height:1.45;margin:0 0 .35rem}.amazon-product-card__price{font-size:1rem;font-weight:700;margin:0 0 .25rem}.amazon-product-card__prices{display:flex;align-items:baseline;gap:.45rem;margin:0 0 .25rem}.amazon-product-card__price-ref{font-size:.8125rem;color:var(--color-muted);text-decoration:line-through}.amazon-product-card__price-sale{font-size:1.25rem;font-weight:900;color:var(--color-sale)}.amazon-product-card__price--muted{font-size:.8125rem;font-weight:500;color:var(--color-muted)}.amazon-product-card__note{font-size:.8125rem;color:var(--color-muted);margin:.35rem 0 0}.amazon-product-card__cta{font-size:.8125rem;margin:0;font-weight:700}.amazon-product-card--cover .amazon-product-card__link{display:flex;flex-direction:column;align-items:stretch;gap:.45rem;height:100%;padding:.5rem}.amazon-product-card--cover .amazon-product-card__image-wrap{aspect-ratio:3 / 4;padding:.25rem}.amazon-product-card--cover .amazon-product-card__image-wrap img{width:100%;max-height:none;height:100%;object-fit:contain}.amazon-product-card--cover .amazon-product-card__body{text-align:center}.amazon-product-card--cover .amazon-product-card__label{font-size:.8125rem;margin:0;color:var(--color-text)}.amazon-product-card--cover .amazon-product-card__price{font-size:.875rem;margin:0}@media(max-width:600px){.amazon-product-cards--covers .amazon-product-cards__list{grid-template-columns:repeat(3,minmax(0,1fr));gap:.5rem}.post-card{grid-template-columns:8rem minmax(0,1fr);gap:var(--space-sm)}}