:root {
  --ink: #111312;
  --paper: #f7f7f5;
  --white: #fff;
  --line: #c8cac7;
  --line-strong: #8d908c;
  --muted: #5f625f;
  --soft: #e7e8e5;
  --grid: rgba(17, 19, 18, .055);
  --content: 1280px;
  --mono: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
  --sans: "Helvetica Neue", "Yu Gothic", "YuGothic", "Hiragino Kaku Gothic ProN", Arial, sans-serif;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  color: var(--ink);
  background-color: var(--paper);
  background-image:
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px),
    linear-gradient(rgba(17,19,18,.025) 1px, transparent 1px),
    linear-gradient(90deg, rgba(17,19,18,.025) 1px, transparent 1px);
  background-size: 32px 32px, 32px 32px, 8px 8px, 8px 8px;
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.85;
}
a { color: inherit; text-decoration: none; }
a:focus-visible, button:focus-visible { outline: 2px solid var(--ink); outline-offset: 4px; }
img, svg { display: block; max-width: 100%; }

.site-shell { width: min(calc(100% - 48px), var(--content)); margin: 0 auto; }
.site-header {
  position: sticky;
  top: 0;
  z-index: 20;
  background: rgba(247,247,245,.94);
  backdrop-filter: blur(12px);
  border-bottom: 1px solid var(--ink);
}
.header-inner { min-height: 84px; display: flex; align-items: center; justify-content: space-between; gap: 24px; }
.brand { display: flex; align-items: center; gap: 14px; font: 700 .84rem/1.15 var(--mono); letter-spacing: .08em; }
.brand-mark { width: 31px; height: 31px; border: 1px solid var(--ink); position: relative; background: var(--ink); }
.brand-mark::before, .brand-mark::after { content: ""; position: absolute; background: var(--paper); }
.brand-mark::before { width: 1px; height: 19px; left: 9px; top: 6px; box-shadow: 11px 0 var(--paper); }
.brand-mark::after { width: 13px; height: 1px; left: 9px; top: 6px; box-shadow: 0 18px var(--paper); }
.brand small { display: block; font-size: .65rem; font-weight: 400; color: var(--muted); letter-spacing: .06em; margin-top: 4px; }
.main-nav { display: flex; align-items: center; gap: 28px; font: 600 .73rem/1 var(--mono); letter-spacing: .06em; }
.main-nav a { padding: 10px 0 8px; border-bottom: 1px solid transparent; }
.main-nav a:hover, body[data-page="home"] .nav-home, body[data-page="roadmap"] .nav-roadmap, body[data-page="logs"] .nav-logs, body[data-page="profile"] .nav-profile { border-color: var(--ink); }
.menu-button { display: none; border: 1px solid var(--ink); background: transparent; width: 44px; height: 40px; font: 700 .7rem var(--mono); }

.eyebrow { margin: 0 0 18px; font: 700 .72rem/1.4 var(--mono); letter-spacing: .12em; text-transform: uppercase; }
.eyebrow::before { content: "[ "; color: var(--line-strong); }
.eyebrow::after { content: " ]"; color: var(--line-strong); }
.page-intro { padding: 72px 0 58px; border-bottom: 1px solid var(--ink); }
.page-intro-grid { display: grid; grid-template-columns: 1fr 360px; gap: 72px; align-items: end; }
h1, h2, h3, p { margin-top: 0; }
h1 { margin-bottom: 24px; max-width: 940px; font-size: clamp(2.45rem, 6.4vw, 6.3rem); line-height: 1.03; letter-spacing: -.055em; font-weight: 700; }
.page-intro h1 { font-size: clamp(2.6rem, 5.4vw, 5.3rem); }
.lead { max-width: 780px; margin-bottom: 0; font-size: clamp(1.05rem, 1.7vw, 1.3rem); line-height: 2; }
.drawing-code { border-left: 1px solid var(--ink); padding: 14px 0 14px 24px; font: .75rem/2 var(--mono); letter-spacing: .04em; }
.drawing-code div { display: flex; justify-content: space-between; gap: 24px; border-bottom: 1px dotted var(--line-strong); }

.hero { min-height: calc(100vh - 84px); border-bottom: 1px solid var(--ink); display: grid; align-content: space-between; padding: 56px 0 34px; }
.hero-top { display: grid; grid-template-columns: 1fr 315px; gap: 64px; }
.hero-title { max-width: 880px; margin: 0; font-size: clamp(3.5rem, 8.3vw, 8.6rem); line-height: .9; letter-spacing: -.075em; }
.hero-title span { display: block; }
.hero-title .outline { color: var(--paper); -webkit-text-stroke: 1.5px var(--ink); }
.hero-copy { align-self: end; padding-bottom: 10px; }
.hero-copy p { margin-bottom: 26px; font-size: 1.08rem; line-height: 2; }
.text-link { display: inline-flex; align-items: center; gap: 20px; border-bottom: 1px solid var(--ink); padding: 0 0 8px; font: 700 .77rem var(--mono); letter-spacing: .08em; }
.text-link::after { content: "→"; font-size: 1.1rem; transition: transform .2s; }
.text-link:hover::after { transform: translateX(5px); }
.hero-bottom { display: grid; grid-template-columns: repeat(4, 1fr); border: 1px solid var(--ink); background: rgba(247,247,245,.83); }
.stat { min-height: 130px; padding: 20px; border-right: 1px solid var(--ink); display: flex; flex-direction: column; justify-content: space-between; }
.stat:last-child { border-right: 0; }
.stat-label { font: .67rem/1.4 var(--mono); letter-spacing: .08em; color: var(--muted); }
.stat-value { margin-top: 20px; font: 700 clamp(1.1rem, 2.2vw, 1.8rem)/1.2 var(--sans); }
.stat-value.large { font: 700 clamp(2.25rem, 4.5vw, 4.2rem)/.85 var(--mono); letter-spacing: -.08em; }

.section { padding: 94px 0; border-bottom: 1px solid var(--ink); }
.section-grid { display: grid; grid-template-columns: 190px 1fr; gap: 72px; }
.section-no { font: 700 4.8rem/.8 var(--mono); letter-spacing: -.1em; color: transparent; -webkit-text-stroke: 1px var(--ink); }
.section-heading { margin-bottom: 34px; font-size: clamp(2rem, 3.8vw, 3.5rem); line-height: 1.12; letter-spacing: -.04em; }
.body-copy { max-width: 780px; }
.body-copy p { margin-bottom: 1.5em; }
.principle { margin-top: 42px; padding: 26px 30px; border: 1px solid var(--ink); background: var(--white); font-size: 1.08rem; }

.progress-panel { display: grid; grid-template-columns: 1fr 1fr; border: 1px solid var(--ink); background: var(--white); }
.progress-main { padding: 34px; border-right: 1px solid var(--ink); }
.progress-main strong { display: block; font: 700 clamp(4rem, 8vw, 7.2rem)/.9 var(--mono); letter-spacing: -.1em; }
.progress-main small { display: block; margin-top: 18px; font: .72rem var(--mono); letter-spacing: .08em; color: var(--muted); }
.progress-list { margin: 0; padding: 0; list-style: none; }
.progress-list li { min-height: 33.33%; padding: 22px 26px; border-bottom: 1px solid var(--ink); display: grid; align-content: center; }
.progress-list li:last-child { border-bottom: 0; }
.progress-list span { font: .67rem var(--mono); color: var(--muted); letter-spacing: .08em; }
.progress-list b { margin-top: 8px; font-size: 1.04rem; }

.roadmap-preview, .roadmap-list { list-style: none; margin: 0; padding: 0; border-top: 1px solid var(--ink); }
.roadmap-preview li, .roadmap-item { display: grid; grid-template-columns: 100px 1fr auto; gap: 28px; padding: 22px 0; border-bottom: 1px solid var(--ink); align-items: center; }
.step-no { font: 700 .95rem var(--mono); }
.step-title { font-weight: 700; font-size: 1.08rem; }
.step-status { border: 1px solid var(--line-strong); padding: 5px 9px; font: .65rem var(--mono); letter-spacing: .06em; white-space: nowrap; }
.step-status.active { background: var(--ink); color: var(--paper); border-color: var(--ink); }
.roadmap-item { grid-template-columns: 110px minmax(0,1fr) 160px; padding: 30px 0; align-items: start; }
.roadmap-item .step-no { font-size: 1.8rem; }
.roadmap-item h2 { margin: 0 0 8px; font-size: 1.35rem; }
.roadmap-item p { margin: 0; max-width: 670px; color: var(--muted); }

.latest-card { display: grid; grid-template-columns: 210px 1fr 80px; border: 1px solid var(--ink); background: var(--white); transition: background .2s, color .2s; }
.latest-card:hover { background: var(--ink); color: var(--white); }
.latest-meta, .latest-body, .latest-arrow { padding: 28px; }
.latest-meta { border-right: 1px solid currentColor; font: .7rem/1.8 var(--mono); }
.latest-body h3 { margin: 0 0 12px; font-size: clamp(1.35rem, 2.5vw, 2rem); line-height: 1.35; }
.latest-body p { margin: 0; color: var(--muted); }
.latest-card:hover .latest-body p { color: #c9cbc8; }
.latest-arrow { border-left: 1px solid currentColor; display: grid; place-items: center; font-size: 1.6rem; }

.goal-line { display: grid; grid-template-columns: repeat(6, 1fr); margin-top: 36px; border-top: 1px solid var(--ink); }
.goal-step { position: relative; padding: 24px 10px 0 0; font: .7rem/1.6 var(--mono); color: var(--muted); }
.goal-step::before { content: ""; position: absolute; top: -5px; left: 0; width: 9px; height: 9px; border: 1px solid var(--ink); background: var(--paper); }
.goal-step:first-child::before { background: var(--ink); }

.log-list { border-top: 1px solid var(--ink); }
.log-row { display: grid; grid-template-columns: 150px 1fr 140px; gap: 30px; padding: 32px 0; border-bottom: 1px solid var(--ink); align-items: start; }
.log-date, .log-time { font: .72rem/1.6 var(--mono); letter-spacing: .05em; }
.log-title { margin: 0 0 12px; font-size: 1.45rem; line-height: 1.35; }
.log-summary { margin: 0; color: var(--muted); }
.log-time { text-align: right; }

.article-layout { display: grid; grid-template-columns: 1fr 310px; gap: 80px; padding: 72px 0 110px; }
.article-body { max-width: 760px; font-size: 1.04rem; }
.article-body p { margin-bottom: 1.65em; }
.article-body .opening { font-size: 1.28rem; line-height: 2; }
.article-note { margin: 42px 0; padding: 26px 28px; border-left: 3px solid var(--ink); background: var(--white); }
.article-aside { position: sticky; top: 120px; align-self: start; border-top: 1px solid var(--ink); }
.article-aside dl { margin: 0; }
.article-aside div { padding: 18px 0; border-bottom: 1px solid var(--line); }
.article-aside dt { font: .65rem var(--mono); letter-spacing: .08em; color: var(--muted); }
.article-aside dd { margin: 7px 0 0; font-weight: 700; }

.profile-block { display: grid; grid-template-columns: 160px 1fr; gap: 50px; padding: 38px 0; border-top: 1px solid var(--ink); }
.profile-block:last-child { border-bottom: 1px solid var(--ink); }
.profile-index { font: 700 1.6rem var(--mono); }
.profile-content h2 { font-size: 1.45rem; margin-bottom: 22px; }
.profile-content p { max-width: 790px; }
.topic-list { display: grid; grid-template-columns: 1fr 1fr; list-style: none; padding: 0; margin: 16px 0 0; border-top: 1px solid var(--line); }
.topic-list li { padding: 13px 0; border-bottom: 1px solid var(--line); }
.topic-list li:nth-child(odd) { padding-right: 20px; }

.site-footer { background: var(--ink); color: var(--paper); padding: 58px 0 30px; }
.footer-top { display: flex; justify-content: space-between; align-items: end; gap: 40px; }
.footer-title { max-width: 630px; margin: 0; font-size: clamp(2rem, 4.6vw, 4.5rem); line-height: .95; letter-spacing: -.06em; }
.footer-meta { font: .68rem/1.9 var(--mono); color: #aeb0ad; text-align: right; }
.footer-bottom { margin-top: 58px; padding-top: 18px; border-top: 1px solid #474947; display: flex; justify-content: space-between; font: .65rem var(--mono); color: #aeb0ad; }

@media (max-width: 900px) {
  .site-shell { width: min(calc(100% - 32px), var(--content)); }
  .menu-button { display: block; }
  .main-nav { display: none; position: absolute; top: 84px; left: 0; right: 0; padding: 18px 16px 26px; background: var(--paper); border-bottom: 1px solid var(--ink); flex-direction: column; align-items: stretch; gap: 2px; }
  .main-nav[data-open="true"] { display: flex; }
  .main-nav a { padding: 14px 8px; border-bottom: 1px solid var(--line); }
  .hero { min-height: auto; gap: 60px; padding-top: 42px; }
  .hero-top, .page-intro-grid { grid-template-columns: 1fr; gap: 42px; }
  .hero-copy { max-width: 620px; }
  .hero-bottom { grid-template-columns: 1fr 1fr; }
  .stat:nth-child(2) { border-right: 0; }
  .stat:nth-child(-n+2) { border-bottom: 1px solid var(--ink); }
  .section-grid { grid-template-columns: 100px 1fr; gap: 32px; }
  .section-no { font-size: 3rem; }
  .article-layout { grid-template-columns: 1fr; gap: 50px; }
  .article-aside { position: static; }
  .latest-card { grid-template-columns: 150px 1fr 64px; }
}

@media (max-width: 640px) {
  body { font-size: 16px; }
  .header-inner { min-height: 72px; }
  .brand small { display: none; }
  .main-nav { top: 72px; }
  .hero { min-height: calc(100svh - 72px); }
  .hero-title { font-size: clamp(3.05rem, 16vw, 5rem); }
  .hero-bottom { grid-template-columns: 1fr; }
  .stat { min-height: 104px; border-right: 0; border-bottom: 1px solid var(--ink); }
  .stat:last-child { border-bottom: 0; }
  .section, .page-intro { padding: 64px 0; }
  .section-grid { grid-template-columns: 1fr; gap: 22px; }
  .section-no { font-size: 2.3rem; }
  .progress-panel { grid-template-columns: 1fr; }
  .progress-main { border-right: 0; border-bottom: 1px solid var(--ink); }
  .roadmap-preview li { grid-template-columns: 52px 1fr; gap: 14px; }
  .roadmap-preview .step-status { grid-column: 2; justify-self: start; }
  .roadmap-item { grid-template-columns: 60px 1fr; gap: 14px; }
  .roadmap-item .step-status { grid-column: 2; justify-self: start; }
  .latest-card { grid-template-columns: 1fr; }
  .latest-meta, .latest-arrow { border: 0; }
  .latest-meta { border-bottom: 1px solid currentColor; }
  .latest-arrow { display: none; }
  .goal-line { grid-template-columns: 1fr 1fr; border-top: 0; }
  .goal-step { border-top: 1px solid var(--ink); margin-top: 14px; }
  .log-row { grid-template-columns: 1fr; gap: 12px; }
  .log-time { text-align: left; }
  .profile-block { grid-template-columns: 1fr; gap: 14px; }
  .topic-list { grid-template-columns: 1fr; }
  .footer-top { align-items: start; flex-direction: column; }
  .footer-meta { text-align: left; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition: none !important; }
}