:root{--ink:#171a22;--muted:#666c79;--line:#e2e4e9;--paper:#f7f8fa;--white:#fff;--accent:#e85c3a;--accent-soft:#fff1ec;--dark:#242936}
*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0;color:var(--ink);background:var(--white);font-family:"Hiragino Sans","Yu Gothic UI","Noto Sans JP",sans-serif;line-height:1.75}a{color:inherit;text-decoration:none}img{display:block;max-width:100%}.story-header{position:relative;z-index:10;display:flex;height:68px;align-items:center;justify-content:space-between;padding:0 max(22px,calc((100vw - 1280px)/2));border-bottom:1px solid var(--line);background:rgba(255,255,255,.94);backdrop-filter:blur(12px)}.brand{display:flex;align-items:center;gap:10px;font-size:1rem;font-weight:850;letter-spacing:.04em}.brand-mark{display:flex;width:30px;height:30px;align-items:flex-end;justify-content:center;gap:2px;padding:7px;border-radius:50%;background:var(--ink)}.brand-mark i{display:block;width:4px;border-radius:4px;background:#ffe0d6}.brand-mark i:nth-child(1){height:7px}.brand-mark i:nth-child(2){height:12px}.brand-mark i:nth-child(3){height:16px}.back-link{font-size:.88rem;font-weight:750}.back-link span{margin-right:7px}.story-hero{display:grid;min-height:calc(100vh - 68px);grid-template-columns:minmax(0,1.06fr) minmax(420px,.94fr);background:var(--paper)}.hero-media{position:relative;min-height:660px;overflow:hidden;background:#e8eaf0}.hero-media:after{position:absolute;inset:0;content:"";background:linear-gradient(180deg,transparent 56%,rgba(15,18,26,.28))}.hero-media img{width:100%;height:100%;object-fit:cover}.media-label{position:absolute;z-index:2;bottom:24px;left:24px;padding:7px 12px;border:1px solid rgba(255,255,255,.45);border-radius:99px;color:#fff;background:rgba(20,23,31,.58);font-size:.75rem;font-weight:800;backdrop-filter:blur(8px)}.hero-play{position:absolute;z-index:3;top:50%;left:50%;display:grid;width:108px;height:108px;place-items:center;border:1px solid rgba(255,255,255,.65);border-radius:50%;color:#fff;background:rgba(23,26,34,.58);transform:translate(-50%,-50%);backdrop-filter:blur(8px);transition:transform .25s,background .25s}.hero-play:hover{background:rgba(201,71,44,.90);transform:translate(-50%,-50%) scale(1.06)}.hero-play span{font-size:1.7rem;line-height:1}.hero-play b{font-size:.72rem}.hero-copy{display:flex;flex-direction:column;justify-content:center;padding:clamp(48px,7vw,100px)}.story-tags{display:flex;gap:7px;flex-wrap:wrap}.story-tags span{padding:5px 9px;border:1px solid #d8dbe3;border-radius:99px;background:#fff;font-size:.75rem;font-weight:800}.story-number{margin:26px 0 12px;color:var(--accent);font:800 .76rem/1.2 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.15em}.hero-copy h1{max-width:680px;margin:0;font-size:clamp(2.4rem,4.2vw,4.8rem);line-height:1.18;letter-spacing:-.055em}.hero-summary{max-width:650px;margin:24px 0 0;color:var(--muted);font-size:1rem;line-height:1.95}.result-reveal{margin:38px 0 0;padding:24px 26px;border-left:4px solid var(--accent);background:#fff;box-shadow:0 15px 35px rgba(32,37,54,.06)}.result-reveal small{display:block;margin-bottom:5px;color:var(--muted);font-size:.78rem;font-weight:750}.result-reveal strong{display:block;font-size:clamp(1.55rem,2.6vw,2.7rem);line-height:1.3;letter-spacing:-.035em}.hero-facts{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin:26px 0 0}.hero-facts div{padding-top:13px;border-top:1px solid #d9dce3}.hero-facts dt{color:var(--muted);font-size:.76rem}.hero-facts dd{margin:2px 0 0;font-size:.9rem;font-weight:800}.story-progress{position:sticky;z-index:9;top:0;display:flex;justify-content:center;border-bottom:1px solid var(--line);background:rgba(255,255,255,.93);backdrop-filter:blur(12px)}.story-progress a{position:relative;display:flex;align-items:center;gap:7px;padding:16px clamp(13px,2.5vw,32px);color:#898e99;font-size:.82rem;font-weight:800}.story-progress a:after{position:absolute;right:0;bottom:-1px;left:0;height:3px;content:"";background:var(--accent);transform:scaleX(0);transition:transform .2s}.story-progress a.is-active{color:var(--ink)}.story-progress a.is-active:after{transform:scaleX(1)}.story-progress span{font:800 .68rem/1 ui-monospace,SFMono-Regular,Menlo,monospace}.story-content{width:min(1040px,calc(100% - 40px));margin:auto}.story-chapter{display:grid;grid-template-columns:180px minmax(0,1fr);gap:68px;padding:110px 0;border-bottom:1px solid var(--line)}.chapter-index{display:flex;flex-direction:column;align-items:flex-start}.chapter-index span{color:var(--accent);font:800 4rem/.9 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:-.08em}.chapter-index small{margin-top:14px;color:#898e99;font:800 .72rem/1.4 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.14em}.chapter-body h2{margin:0 0 27px;font-size:clamp(2rem,4vw,3.7rem);line-height:1.28;letter-spacing:-.045em}.chapter-body>p{max-width:750px;margin:0;font-size:1.12rem;line-height:2}.method-facts{display:grid;grid-template-columns:repeat(3,1fr);gap:12px;margin-top:38px}.method-facts div{padding:19px;border:1px solid var(--line);border-radius:10px;background:var(--paper)}.method-facts span{display:block;color:var(--muted);font-size:.76rem}.method-facts strong{display:block;margin-top:4px;font-size:1rem}.human-note{margin-top:30px!important;padding:24px 27px;border-radius:11px;background:var(--accent-soft);font-size:.93rem!important;font-weight:700}.before-after{display:grid;grid-template-columns:1fr auto 1fr;gap:17px;align-items:stretch;margin-top:42px}.before-after article{padding:28px;border:1px solid var(--line);border-radius:13px;background:var(--paper)}.before-after article:last-child{border-color:#f0b5a5;background:#fff7f4}.before-after span{color:#787e8b;font:850 .72rem/1.2 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.15em}.before-after p{margin:12px 0 0;font-size:.98rem;line-height:1.8}.before-after i{align-self:center;color:#737988;font-size:1.3rem;font-style:normal}blockquote{margin:38px 0 0;padding:34px 38px;border-radius:14px;color:#fff;background:var(--dark)}blockquote p{margin:0;font-size:clamp(1.2rem,2.5vw,1.8rem);line-height:1.65}blockquote cite{display:block;margin-top:14px;color:#c7cbd4;font-size:.78rem;font-style:normal}.evidence-level{display:flex;align-items:center;justify-content:space-between;gap:20px;margin-top:36px;padding:20px 24px;border:1px solid #efb7a8;border-radius:10px;background:var(--accent-soft)}.evidence-level span{font-size:.8rem;font-weight:800}.evidence-level strong{font-size:1rem}.chapter-body aside{margin-top:18px;padding:25px 27px;border-radius:10px;background:#f1f2f4}.chapter-body aside strong{font-size:.9rem}.chapter-body aside p{margin:8px 0 0;color:var(--muted);font-size:.88rem;line-height:1.8}.video-story{width:min(1180px,calc(100% - 40px));margin:110px auto}.section-label span,.source-panel>div>span,.related-head>p{color:var(--accent);font:800 .72rem/1.3 ui-monospace,SFMono-Regular,Menlo,monospace;letter-spacing:.16em}.section-label p{margin:5px 0 20px;font-size:1.65rem;font-weight:850}.video-frame{position:relative;aspect-ratio:16/9;overflow:hidden;border-radius:18px;background:#11131a;box-shadow:0 28px 70px rgba(19,22,31,.18)}.video-frame iframe{position:absolute;inset:0;width:100%;height:100%;border:0}.media-note{margin:12px 3px 0;color:var(--muted);font-size:.78rem}.source-panel{display:grid;width:min(1040px,calc(100% - 40px));grid-template-columns:1fr 1fr;gap:42px;margin:110px auto;padding:48px;border-radius:18px;color:#fff;background:var(--dark)}.source-panel h2{margin:8px 0 12px;font-size:2rem}.source-panel p{margin:0;color:#c7cbd4;font-size:.9rem}.source-panel>a{display:flex;flex-direction:column;align-items:flex-start;justify-content:center;padding:24px;border:1px solid #555b6a;border-radius:12px;background:#303645}.source-panel>a small{color:#c7cbd4;font-size:.76rem}.source-panel>a strong{margin:5px 0 18px;font-size:1.1rem}.source-panel>a b{color:#ffe0d6;font-size:.86rem}.source-panel dl{display:grid;grid-column:1/-1;grid-template-columns:1fr 1fr;gap:16px;margin:0;padding-top:25px;border-top:1px solid #454b59}.source-panel dt{color:#aeb3bf;font-size:.72rem}.source-panel dd{margin:3px 0 0;font-size:.82rem;font-weight:750}.related-section{padding:105px max(22px,calc((100vw - 1180px)/2));background:var(--paper)}.related-head p{margin:0}.related-head h2{margin:10px 0 36px;font-size:clamp(2rem,4vw,3.5rem);letter-spacing:-.04em}.related-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:18px}.related-grid a{display:flex;min-width:0;flex-direction:column;overflow:hidden;border:1px solid var(--line);border-radius:13px;background:#fff;transition:transform .2s,box-shadow .2s}.related-grid a:hover{transform:translateY(-4px);box-shadow:0 17px 35px rgba(27,31,44,.09)}.related-grid img{width:100%;aspect-ratio:16/9;object-fit:cover}.related-grid span{margin:18px 20px 0;color:var(--accent);font-size:.72rem;font-weight:800}.related-grid strong{margin:8px 20px 0;font-size:1rem;line-height:1.6}.related-grid small{margin:auto 20px 19px;padding-top:16px;color:var(--muted);font-size:.76rem}.all-cases{display:inline-block;margin-top:30px;padding-bottom:4px;border-bottom:1px solid var(--ink);font-size:.9rem;font-weight:800}footer{display:flex;align-items:center;justify-content:space-between;gap:30px;padding:38px max(22px,calc((100vw - 1180px)/2));color:#c2c6d0;background:#171a22}footer a{color:#fff;font-weight:850}footer p{margin:0;font-size:.76rem}.reveal{opacity:0;transform:translateY(24px);transition:opacity .55s ease,transform .55s ease}.reveal.is-visible{opacity:1;transform:none}
@media(max-width:900px){.story-hero{grid-template-columns:1fr}.hero-media{min-height:58vh}.hero-copy{padding:58px 24px 68px}.story-progress{overflow-x:auto;justify-content:flex-start}.story-progress a{flex:0 0 auto}.story-chapter{grid-template-columns:110px 1fr;gap:32px}.chapter-index span{font-size:3rem}.related-grid{grid-template-columns:1fr 1fr}.source-panel{grid-template-columns:1fr}}
@media(max-width:620px){.story-header{height:62px;padding:0 17px}.brand{font-size:.9rem}.back-link{font-size:.78rem}.story-hero{min-height:auto}.hero-media{min-height:54vw;aspect-ratio:4/3}.media-label{bottom:13px;left:13px}.hero-play{width:82px;height:82px}.hero-copy{padding:38px 19px 50px}.story-number{margin-top:20px}.hero-copy h1{font-size:2.15rem}.hero-summary{font-size:.96rem}.result-reveal{margin-top:28px;padding:20px}.result-reveal strong{font-size:1.55rem}.hero-facts{gap:8px}.hero-facts dd{font-size:.78rem}.story-progress a{padding:13px 15px}.story-progress a:not(.is-active){font-size:0}.story-progress a:not(.is-active) span{font-size:.68rem}.story-content{width:calc(100% - 38px)}.story-chapter{grid-template-columns:1fr;gap:24px;padding:72px 0}.chapter-index{display:block}.chapter-index span{font-size:2.2rem}.chapter-index small{margin:0 0 0 13px}.chapter-body h2{margin-bottom:20px;font-size:2rem}.chapter-body>p{font-size:1rem;line-height:1.9}.method-facts{grid-template-columns:1fr;margin-top:28px}.before-after{grid-template-columns:1fr;margin-top:30px}.before-after i{justify-self:center;transform:rotate(90deg)}blockquote{padding:26px;margin-top:28px}.evidence-level{align-items:flex-start;flex-direction:column}.video-story,.source-panel{width:calc(100% - 38px);margin:75px auto}.video-frame{border-radius:12px}.source-panel{padding:29px 22px}.source-panel dl{grid-template-columns:1fr}.related-section{padding:72px 19px}.related-grid{grid-template-columns:1fr}.related-grid strong{font-size:1.02rem}footer{align-items:flex-start;flex-direction:column;padding:32px 19px}.reveal{opacity:1;transform:none}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}.reveal{opacity:1;transform:none;transition:none}.hero-play,.related-grid a{transition:none}}
.related-head>span{display:block;max-width:43em;margin:-22px 0 34px;color:var(--muted);font-size:.88rem}.related-next{display:grid;grid-template-columns:minmax(280px,.9fr) minmax(0,1.1fr);overflow:hidden;margin-bottom:18px;border:1px solid #e5b5a8;border-radius:16px;background:#fff}.related-next>img{width:100%;height:100%;min-height:300px;object-fit:cover}.related-next>div{display:flex;flex-direction:column;justify-content:center;padding:38px}.related-next span{color:var(--accent);font-size:.72rem;font-weight:850}.related-next strong{margin-top:11px;font-size:clamp(1.5rem,2.5vw,2.25rem);line-height:1.4;letter-spacing:-.035em}.related-next p{margin:15px 0 0;color:var(--muted);font-size:.88rem}.related-next b{margin-top:25px;font-size:.85rem}.related-grid--more{grid-template-columns:repeat(2,1fr)}.related-paths{display:flex;gap:9px;flex-wrap:wrap;margin-top:28px}.related-paths a{padding:11px 14px;border:1px solid #d9dce2;border-radius:9px;background:#fff;font-size:.78rem;font-weight:850}.related-paths a:first-child{border-color:var(--accent);color:#fff;background:var(--accent)}
@media(max-width:900px){.related-next{grid-template-columns:1fr}.related-next>img{min-height:0;aspect-ratio:16/9}}
@media(max-width:620px){.related-head>span{margin-top:-22px}.related-next>div{padding:25px 21px}.related-next strong{font-size:1.35rem}.related-grid--more{grid-template-columns:1fr}.related-paths{flex-direction:column}.related-paths a{text-align:center}}
.video-story--short{max-width:760px}.video-story--short .video-frame{max-width:420px;margin-left:auto;margin-right:auto;aspect-ratio:9/16}.video-story--short .media-note{max-width:420px;margin-left:auto;margin-right:auto}
.review-banner{display:flex;gap:14px;align-items:center;justify-content:center;padding:12px 20px;color:#5d4c12;background:#fff5cc;font-size:.82rem}.review-banner strong{font-size:.84rem}.review-banner span{color:#746635}
.story-share{display:flex;width:100%;align-items:center;justify-content:space-between;margin-top:18px;padding:12px 15px;border:1px solid #d7dae1;border-radius:8px;color:var(--ink);background:transparent;font-size:.76rem;font-weight:850;cursor:pointer;transition:border-color .2s,background .2s}.story-share:hover{border-color:var(--accent);background:var(--accent-soft)}.story-share b{color:var(--accent);font-size:.95rem}
.story-header-actions{display:flex;align-items:center;gap:22px;font-size:.82rem;font-weight:800}.story-save{display:flex;width:100%;align-items:center;justify-content:space-between;margin-top:9px;padding:12px 15px;border:1px solid #d7dae1;border-radius:8px;color:var(--ink);background:#fff;font-size:.76rem;font-weight:850;cursor:pointer}.story-save:hover,.story-save.is-saved{border-color:var(--accent);background:var(--accent-soft)}.story-save b{color:var(--accent);font-size:1rem}.story-save.is-saved b{font-size:0}.story-save.is-saved b:after{content:'✓';font-size:1rem}@media(max-width:620px){.story-header-actions>a:first-child{display:none}}
@media(max-width:620px){.review-banner{align-items:flex-start;flex-direction:column;gap:2px;padding:11px 17px}.review-banner span{font-size:.75rem;line-height:1.5}}
footer nav{display:flex;gap:16px;flex-wrap:wrap}footer nav a{color:#c2c6d0;font-size:.72rem;font-weight:700;text-decoration:underline;text-underline-offset:4px}
.brand-symbol{width:44px;height:28px;flex:0 0 auto;overflow:visible}.brand-symbol path{fill:none;stroke:var(--ink);stroke-width:3;stroke-linecap:round}.brand-symbol .brand-start{fill:var(--ink)}.brand-symbol .brand-end{fill:var(--accent)}.brand-word{display:inline-flex;align-items:baseline;letter-spacing:-.03em;font-weight:650;white-space:nowrap}.brand-word strong{font-weight:900}.brand-word b{color:#b93d24;font-weight:900}

/* Desktop typography polish. */
.hero-copy h1,.chapter-body h2,.result-reveal strong,.related-head h2,.related-next strong,.source-panel h2,.start-challenge h2{text-wrap:balance;line-break:strict;overflow-wrap:anywhere}
.hero-copy h1{max-width:11.5em;font-size:clamp(2.55rem,3.8vw,4.35rem);line-height:1.2}
.hero-summary{max-width:36em}
.chapter-body h2{max-width:14em}
.related-head h2{max-width:16em;line-height:1.25}
@media(max-width:1100px){.story-hero{grid-template-columns:minmax(0,1fr) minmax(390px,.95fr)}.hero-copy{padding:clamp(44px,5vw,70px)}}
@media(max-width:900px){.story-hero{grid-template-columns:1fr}.hero-copy h1{max-width:15em}}

/* Reading progress and desktop interaction polish. */
.story-read-progress{position:absolute;right:0;bottom:-1px;left:0;height:3px;background:var(--accent);transform:scaleX(0);transform-origin:left center;pointer-events:none;will-change:transform}
@media(prefers-reduced-motion:reduce){.story-read-progress{will-change:auto}}