:root {
  --paper: #f8f8f6;
  --ink: #1c1c1c;
  --body: #30302d;
  --quiet: #77776f;
  --rule: #deded6;
  --rail: #1c1c1c;
  --rail-text: #aaa99e;
  --signal: #718660;
  --signal-dark: #506245;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

body {
  min-width: 320px;
  margin: 0;
  color: var(--ink);
  background: var(--paper);
  font-family: "IBM Plex Serif", Georgia, serif;
  font-size: 17px;
  line-height: 1.65;
}

.layout { display: flex; min-height: 100vh; }

.rail {
  position: sticky;
  top: 0;
  width: 17.25rem;
  height: 100vh;
  flex: 0 0 auto;
  display: flex;
  flex-direction: column;
  padding: 2.5rem 1.75rem;
  color: var(--rail-text);
  background: var(--rail);
  font-family: "IBM Plex Mono", Consolas, monospace;
  font-size: .8rem;
}

.brand { display: inline-flex; align-items: center; gap: .7rem; width: max-content; color: #e6e6dc; font-size: .84rem; font-weight: 500; letter-spacing: .11em; text-decoration: none; text-transform: uppercase; }
.sigil { position: relative; width: 2.25rem; height: 2.25rem; display: inline-block; border: 1px solid #6f8065; transform: rotate(45deg); }
.sigil i { position: absolute; display: block; border: 1px solid #9bad8d; }
.sigil i:nth-child(1) { inset: .37rem; }
.sigil i:nth-child(2) { inset: .68rem; border-color: #6f8065; }
.sigil i:nth-child(3) { top: .91rem; left: .91rem; width: .3rem; height: .3rem; border: 0; background: #b5c5a8; }

.rail-statement { max-width: 12rem; margin: 1.35rem 0 3.5rem; color: #74746d; font-size: .74rem; line-height: 1.55; }
nav { display: grid; gap: .45rem; }
nav a { color: #8d8d84; text-decoration: none; transition: color .15s ease; }
nav a::before { content: "› "; color: #55554e; }
nav a:hover { color: #e0e0d7; }
nav a:hover::before { color: #a4ba91; }
.rail-status { display: flex; align-items: center; gap: .5rem; margin: auto 0 0; color: #74746d; font-size: .67rem; letter-spacing: .07em; text-transform: uppercase; }
.rail-status span { width: .42rem; height: .42rem; border-radius: 50%; background: var(--signal); box-shadow: 0 0 0 .2rem rgba(113, 134, 96, .12); }

.content { flex: 1; display: flex; flex-direction: column; background-color: var(--paper); background-image: linear-gradient(rgba(75, 75, 67, .035) 1px, transparent 1px), linear-gradient(90deg, rgba(75, 75, 67, .035) 1px, transparent 1px); background-size: 26px 26px; }
main { width: min(100% - 6rem, 56rem); flex: 1; padding: 4.7rem 0 3.75rem; }

.kicker, .section-label, .number, footer { font-family: "IBM Plex Mono", Consolas, monospace; font-size: .68rem; letter-spacing: .1em; text-transform: uppercase; }
.kicker { margin: 0 0 1.2rem; color: var(--signal-dark); }
h1, h2, h3, p { margin-top: 0; }
h1 { max-width: 10ch; margin-bottom: 1.5rem; font-size: clamp(3.75rem, 8.6vw, 7.8rem); font-weight: 400; letter-spacing: -.065em; line-height: .91; }
h1 em { color: var(--signal-dark); font-weight: inherit; }
.lede { max-width: 31rem; margin-bottom: 4.25rem; color: #45453f; font-size: clamp(1.15rem, 2vw, 1.4rem); line-height: 1.55; }

.principles { padding-top: .8rem; border-top: 1px solid var(--rule); }
h2 { margin-bottom: 1.2rem; font-family: "IBM Plex Mono", Consolas, monospace; font-size: .78rem; font-weight: 500; letter-spacing: .08em; text-transform: uppercase; }
.principle-grid { display: grid; grid-template-columns: repeat(3, 1fr); border-top: 1px solid var(--rule); border-left: 1px solid var(--rule); }
.principle-grid article { min-height: 14rem; padding: 1.2rem 1.25rem; border-right: 1px solid var(--rule); border-bottom: 1px solid var(--rule); background: rgba(248, 248, 246, .72); }
.number { display: block; margin-bottom: 2.6rem; color: var(--signal-dark); }
.principle-grid h3 { margin-bottom: .55rem; font-family: "IBM Plex Mono", Consolas, monospace; font-size: 1rem; font-weight: 500; }
.principle-grid p { margin-bottom: 0; color: #5f5f58; font-size: .94rem; line-height: 1.58; }

.approach { max-width: 38rem; margin-top: 4.5rem; padding-top: .8rem; border-top: 1px solid var(--rule); }
.section-label { margin-bottom: .95rem; color: var(--signal-dark); }
.approach h2 { margin-bottom: .75rem; font-family: "IBM Plex Serif", Georgia, serif; font-size: clamp(2rem, 4vw, 3rem); font-weight: 400; letter-spacing: -.04em; text-transform: none; }
.approach p:last-child { margin-bottom: 0; color: var(--body); font-size: 1.1rem; line-height: 1.68; }

footer { display: flex; justify-content: space-between; width: min(100% - 6rem, 56rem); padding: 1.45rem 0; border-top: 1px solid var(--rule); color: var(--quiet); }

@media (max-width: 800px) {
  .layout { display: block; }
  .rail { position: relative; width: auto; height: auto; min-height: 12rem; padding: 1.5rem; }
  .rail-statement { margin: 1rem 0 1.4rem; }
  nav { grid-template-columns: repeat(2, max-content); column-gap: 1.4rem; }
  .rail-status { margin-top: 1.7rem; }
  main { width: min(100% - 3rem, 56rem); padding: 3rem 0; }
  footer { width: min(100% - 3rem, 56rem); }
}

@media (max-width: 560px) {
  h1 { font-size: clamp(3.35rem, 17vw, 5rem); }
  .principle-grid { grid-template-columns: 1fr; }
  .principle-grid article { min-height: auto; }
  .number { margin-bottom: 1.75rem; }
  .approach { margin-top: 3.5rem; }
  footer { display: grid; gap: .5rem; }
}