/* 01 Design tokens */
:root {
  --basalt: #202827; --deep-steel: #344c55; --process-blue: #506e7c; --clay: #9a6952;
  --amber: #b28b55; --sage: #68786a; --plum: #6f5d6d; --graphite: #363d3d;
  --muted: #747f80; --mist: #e4e9e7; --steel-wash: #e1e8ea; --clay-wash: #eee3dd;
  --amber-wash: #f2e9d9; --sage-wash: #e5e9e3; --plum-wash: #eae3e8;
  --field-paper: #f6f2e9; --clean-paper: #fbfaf7; --white: #fff;
  --font-editorial: Georgia, Cambria, "Times New Roman", Times, serif;
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Monaco, Consolas, "Liberation Mono", monospace;
  --fs-sm: .76rem; --fs-base: clamp(.95rem, .9rem + .15vw, 1.05rem); --fs-h3: clamp(1.35rem, 1.15rem + .6vw, 1.85rem);
  --fs-h2: clamp(2rem, 1.3rem + 2vw, 3.5rem); --fs-h1: clamp(2.8rem, 1.75rem + 3.3vw, 5.5rem);
  --space-xs: .5rem; --space-sm: .85rem; --space-md: 1.5rem; --space-lg: 2.5rem; --space-xl: clamp(4rem, 8vw, 8rem);
  --container: 1200px; --border: 1px solid rgba(32,40,39,.2); --radius: 2px;
  --shadow: 0 18px 45px rgba(32,40,39,.08); --transition: 220ms ease;
}

/* 02 Reset */
*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 78px; }
body, h1, h2, h3, p, ul { margin: 0; }
ul { padding: 0; } img { display: block; max-width: 100%; }
button, input { font: inherit; } a { color: inherit; }

/* 03 Base */
body { background: var(--field-paper); color: var(--graphite); font-family: var(--font-sans); font-size: var(--fs-base); line-height: 1.65; overflow-x: hidden; }
::selection { background: var(--amber); color: var(--basalt); }
.container { width: min(calc(100% - 3rem), var(--container)); margin-inline: auto; }
.section { padding: var(--space-xl) 0; }

/* 04 Accessibility */
.skip-link { position: fixed; z-index: 100; top: .5rem; left: .5rem; background: var(--white); color: var(--basalt); padding: .8rem 1rem; transform: translateY(-150%); }
.skip-link:focus { transform: none; }
:focus-visible { outline: 3px solid var(--amber); outline-offset: 4px; }
[hidden] { display: none !important; }
.clipboard-fallback { position: fixed; left: -9999px; }

/* 05 Typography */
h1, h2, h3 { color: var(--basalt); font-family: var(--font-editorial); font-weight: 400; line-height: 1.08; }
h1 { font-size: var(--fs-h1); letter-spacing: -.04em; } h2 { font-size: var(--fs-h2); letter-spacing: -.025em; } h3 { font-size: var(--fs-h3); }
.eyebrow, .number, .profile-category, .interface-label { color: var(--clay); font-family: var(--font-mono); font-size: var(--fs-sm); font-weight: 700; letter-spacing: .12em; text-transform: uppercase; }
.section-heading { max-width: 800px; margin-bottom: clamp(2.5rem, 5vw, 5rem); }
.section-heading h2 { margin-top: .7rem; }
.section-heading > p:not(.eyebrow) { margin-top: 1rem; max-width: 70ch; }

/* 06 Layout */
.button-row { display: flex; flex-wrap: wrap; gap: .7rem; margin-top: 2rem; }
.button { display: inline-flex; min-height: 48px; align-items: center; justify-content: center; padding: .7rem 1.15rem; border: 1px solid var(--basalt); font-family: var(--font-mono); font-size: .75rem; letter-spacing: .05em; text-decoration: none; text-transform: uppercase; transition: var(--transition); }
.button-primary { background: var(--basalt); color: var(--white); }.button-primary:hover { background: var(--deep-steel); }
.button-secondary:hover { background: var(--white); }.button-light { background: var(--field-paper); color: var(--basalt); }.button-outline { border-color: var(--field-paper); color: var(--field-paper); }
.boundary { border-top: var(--border); font-size: .77rem; line-height: 1.55; margin-top: auto; padding-top: 1rem; }

/* 07 Header */
.site-header { position: sticky; z-index: 50; top: 0; background: rgba(32,40,39,.98); border-bottom: 1px solid rgba(255,255,255,.1); }
.header-inner { display: flex; min-height: 72px; align-items: center; justify-content: space-between; gap: 1.5rem; }
.brand { width: 288px; flex: 0 0 auto; }.brand img { width: 100%; }
.primary-navigation { display: flex; align-items: center; gap: clamp(.5rem, 1vw, 1.2rem); color: var(--mist); }
.primary-navigation a { font-size: .72rem; line-height: 1.2; text-decoration: none; white-space: nowrap; }.primary-navigation a:hover { color: var(--white); }
.primary-navigation .nav-cta { border: 1px solid var(--amber); padding: .7rem .8rem; color: var(--white); }
.menu-toggle { display: none; width: 44px; height: 40px; border: 1px solid rgba(255,255,255,.3); background: transparent; }
.menu-toggle span { display: block; width: 20px; height: 1px; margin: 6px auto; background: var(--white); }

/* 08 Hero */
.hero { min-height: calc(100vh - 72px); background: var(--field-paper); position: relative; }
.hero::before { content: ""; position: absolute; inset: 0 0 0 48%; background: var(--mist); border-left: 1px solid rgba(32,40,39,.12); }
.hero-grid { display: grid; min-height: calc(100vh - 72px); grid-template-columns: 48% 52%; align-items: center; }
.hero-copy { position: relative; z-index: 1; padding: 5rem 4.5rem 5rem 0; }.hero-copy h1 { margin-top: 1.25rem; }.hero-copy h1 em { color: var(--clay); font-style: normal; }
.hero-intro { max-width: 61ch; margin-top: 1.8rem; }.micro-status { margin-top: 2.2rem; font-family: var(--font-mono); font-size: .72rem; text-transform: uppercase; }
.status-dot { display: inline-block; width: 8px; height: 8px; margin-right: .55rem; background: var(--sage); }
.hero-architecture { position: relative; height: min(610px, 72vh); margin-left: clamp(2rem, 5vw, 5.5rem); display: flex; align-items: flex-start; gap: clamp(2rem, 3.5vw, 4.3rem); }
.hero-architecture > p { position: absolute; right: 0; bottom: 0; max-width: 38rem; border-top: 2px solid var(--basalt); padding: 1.2rem 0 0 4rem; font-family: var(--font-editorial); font-size: 1.15rem; }

/* 09 Operating Spines */
.spine { position: relative; width: 4.5rem; padding-top: 3rem; border-left: 4px solid var(--basalt); display: flex; flex-direction: column; gap: clamp(2.6rem, 5vh, 4.5rem); }
.spine::before { content: ""; position: absolute; width: 13px; height: 13px; top: 22%; left: -8px; border: 2px solid currentColor; border-radius: 50%; background: var(--mist); }
.spine::after { content: ""; position: absolute; width: 15px; height: 13px; left: -9px; bottom: 22%; background: currentColor; }
.spine b { position: absolute; top: 0; left: -.2rem; width: 8rem; font: 700 .66rem var(--font-mono); letter-spacing: .06em; text-transform: uppercase; transform: rotate(90deg) translateY(-100%); transform-origin: left top; }
.spine span { position: relative; left: 1rem; font: .66rem var(--font-mono); text-transform: uppercase; white-space: nowrap; }
.spine span::before { content: ""; position: absolute; top: 50%; right: calc(100% + .6rem); width: 1.6rem; border-top: 2px solid currentColor; }
.spine i { height: 17px; margin-left: -5px; border-left: 6px solid var(--mist); }
.spine-resource { height: 78%; color: var(--process-blue); margin-top: 15%; }.spine-process { height: 64%; color: var(--clay); margin-top: 2%; }.spine-network { height: 82%; color: var(--sage); margin-top: 9%; }.spine-horizon { height: 69%; color: var(--plum); margin-top: 0; }

/* 10 Crosspoints */
.crosspoint { position: relative; width: 42px; height: 32px; margin-bottom: 1.3rem; }
.crosspoint::before { content: ""; position: absolute; top: 14px; left: 0; width: 40px; border-top: 2px solid var(--clay); box-shadow: 20px -10px 0 -7px var(--clay); }
.crosspoint::after { content: ""; position: absolute; left: 15px; top: 2px; width: 13px; height: 13px; border: 2px solid var(--clay); border-radius: 50%; }

/* 11 System Signal Strip */
.signal-strip { background: var(--basalt); color: var(--mist); padding: 3rem 0; }.signal-strip .eyebrow { color: var(--amber); }.signal-lead { max-width: 76ch; margin: .6rem 0 2rem; font-family: var(--font-editorial); font-size: 1.35rem; }
.signal-grid { display: grid; grid-template-columns: repeat(4,1fr); border-top: 1px solid rgba(255,255,255,.2); }.signal-grid span { padding: 1rem 1rem 0 0; font-family: var(--font-mono); font-size: .78rem; }

/* 12 Energy Systems */
.systems-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 1px; background: rgba(32,40,39,.18); border: var(--border); }
.system-card { display: flex; min-height: 550px; flex-direction: column; padding: 1.7rem; background: var(--clean-paper); border-top: 7px solid; }.system-card h3 { margin: 2.5rem 0 1.2rem; }.system-card > p:not(.boundary) { font-size: .92rem; }
.system-card ul { margin: 2rem 0; list-style: none; }.system-card li { border-top: var(--border); padding: .45rem 0; font: .7rem var(--font-mono); text-transform: uppercase; }
.upstream { border-color: var(--process-blue); }.downstream { border-color: var(--clay); }.reliability { border-color: var(--sage); }.transition { border-color: var(--plum); }

/* 13 System Interfaces */
.interfaces { background: var(--clean-paper); }.interface-list { display: grid; gap: 1.5rem; }.interface { display: grid; grid-template-columns: .65fr 1.5fr 1fr; gap: 2rem; align-items: start; padding: 2.2rem; border-top: 3px solid var(--deep-steel); background: var(--field-paper); }
.interface h3 span { color: var(--clay); }.interface .question { font-family: var(--font-editorial); font-size: clamp(1.3rem, 2vw, 2rem); line-height: 1.25; }.interface b { font: .7rem var(--font-mono); text-transform: uppercase; }.interface .boundary { grid-column: 2 / -1; }
.interface-two { margin-left: 7%; border-color: var(--clay); }.interface-three { margin-right: 7%; border-color: var(--plum); }

/* 14 System Horizon Review */
.method { background: var(--steel-wash); }.method-grid { display: grid; grid-template-columns: repeat(12,1fr); gap: 1rem; }
.method-step { position: relative; min-height: 270px; padding: 4.5rem 1.4rem 1.4rem; background: var(--clean-paper); border-left: 3px solid var(--deep-steel); }.method-step::before { content: ""; position: absolute; left: -7px; top: 27px; width: 11px; height: 11px; border: 2px solid var(--deep-steel); border-radius: 50%; background: var(--steel-wash); }
.method-step span { position: absolute; top: 1rem; right: 1rem; font: .7rem var(--font-mono); }.method-step h3 { margin-bottom: 1rem; }.method-step p { font-size: .87rem; }
.method-step:nth-child(1),.method-step:nth-child(2),.method-step:nth-child(3) { grid-column: span 4; }.method-step:nth-child(n+4) { grid-column: span 3; }

/* 15 Professional Checklist */
.checklist { display: grid; grid-template-columns: .8fr 1.2fr; gap: 4rem; margin-top: 4rem; padding: clamp(2rem,5vw,4.5rem); background: var(--basalt); color: var(--mist); }.checklist h2 { color: var(--white); margin: .5rem 0 1rem; }.checklist .eyebrow { color: var(--amber); }.checklist ul { columns: 2; list-style: none; }.checklist li { break-inside: avoid; border-top: 1px solid rgba(255,255,255,.18); padding: .6rem 1rem .6rem 0; font-size: .82rem; }

/* 16 Reference Profiles */
.profile-grid { display: grid; grid-template-columns: repeat(3,1fr); gap: 1.2rem; }.profile { position: relative; padding: 1.7rem; background: var(--clean-paper); border: var(--border); overflow: hidden; }.profile::after { content: ""; position: absolute; top: 0; right: 1rem; height: 58px; border-left: 3px solid var(--clay); }
.avatar { display: grid; width: 62px; height: 62px; place-items: center; background: var(--deep-steel); color: var(--white); font: 700 .9rem var(--font-mono); }.profile-category { margin: 1.5rem 0 .5rem; }.profile h3 { margin-bottom: 1rem; }.profile-role { min-height: 5rem; color: var(--muted); font-size: .77rem; font-weight: 600; text-transform: uppercase; }.profile > p:not(.profile-category,.profile-role,.tags,.contact-note) { margin-top: 1rem; font-size: .88rem; }
.tags { margin: 1.2rem 0; color: var(--deep-steel); font: .7rem/1.7 var(--font-mono); }.contact { display: grid; gap: .5rem; margin-top: 1.5rem; border-top: var(--border); padding-top: 1rem; }.contact b,.reference-type { color: var(--clay); font: 700 .7rem var(--font-mono); text-transform: uppercase; }.contact a { overflow-wrap: anywhere; font-size: .85rem; }.copy-email { width: max-content; border: 1px solid var(--basalt); background: transparent; padding: .55rem .75rem; cursor: pointer; font: .7rem var(--font-mono); text-transform: uppercase; }.contact-note { margin-top: 1rem; color: var(--muted); font-size: .7rem; }
.profile-b { margin-top: 2rem; background: var(--steel-wash); }.profile-c .avatar { margin-left: auto; background: var(--clay); }.profile-d { background: var(--plum-wash); }.profile-e { margin-top: 2rem; }.profile-e::after { left: 1rem; right: auto; border-color: var(--plum); }.profile-f { background: var(--sage-wash); }.reference-type { display: block; margin-top: 2rem; border-top: var(--border); padding-top: 1rem; }

/* 17 Independence Note */
.independence-note { background: var(--amber-wash); border-block: var(--border); padding: 4rem 0; }.independence-grid { display: grid; grid-template-columns: .8fr 1.2fr; gap: 4rem; }.independence-grid h2 { margin-top: .7rem; }.independence-grid div:last-child { columns: 2; column-gap: 2rem; }.independence-grid div:last-child p { break-inside: avoid; margin-bottom: 1rem; font-size: .83rem; }

/* 18 Energy System Notes */
.notes { background: var(--clean-paper); }.notes-grid { display: grid; grid-template-columns: repeat(2,1fr); gap: 1rem; }.note-card { border: var(--border); background: var(--field-paper); }.note-card details { height: 100%; }.note-card summary { min-height: 300px; padding: 1.7rem; cursor: pointer; list-style: none; display: flex; flex-direction: column; }.note-card summary::-webkit-details-marker { display: none; }.note-card summary span { color: var(--clay); font: 700 .7rem var(--font-mono); letter-spacing: .1em; text-transform: uppercase; }.note-card summary h3 { margin: 2.5rem 0 1rem; }.note-card summary p { font-size: .9rem; }.note-card summary b { margin-top: auto; padding-top: 1.5rem; font: .7rem var(--font-mono); text-transform: uppercase; }.note-card[open],.note-card:has(details[open]) { border-color: var(--deep-steel); }.note-body { border-top: var(--border); padding: 1.7rem; background: var(--steel-wash); }.note-body p:first-child { font-size: .9rem; }.no-results { padding: 3rem; border: var(--border); text-align: center; font-family: var(--font-editorial); font-size: 1.4rem; }

/* 19 Search */
.search-panel { display: grid; grid-template-columns: 1fr auto; gap: .7rem 1.5rem; margin-bottom: 2rem; padding: 1.4rem; background: var(--basalt); color: var(--white); }.search-panel label { grid-column: 1 / -1; font: .75rem var(--font-mono); text-transform: uppercase; }.search-row { display: flex; gap: .5rem; }.search-row input { width: 100%; min-width: 0; border: 1px solid var(--muted); border-radius: 0; background: var(--white); padding: .85rem; }.search-row button { border: 1px solid var(--amber); background: transparent; color: var(--white); padding: .7rem 1rem; white-space: nowrap; cursor: pointer; }.search-panel > p { align-self: center; font: .75rem var(--font-mono); }

/* 20 About */
.about-grid { display: grid; grid-template-columns: 1fr 1fr; gap: clamp(2rem,8vw,8rem); }.about-copy { border-left: 3px solid var(--clay); padding-left: 2rem; }.about-copy p { margin-bottom: 1.2rem; }

/* 21 Principles */
.principles { padding: 0 0 var(--space-xl); }.principles-grid { display: grid; grid-template-columns: repeat(4,1fr); border: var(--border); }.principles article { padding: 2rem; border-right: var(--border); }.principles article:last-child { border: 0; }.principles span { font: .7rem var(--font-mono); }.principles h3 { margin: 2.5rem 0 1rem; text-transform: uppercase; }.principles p { font-size: .85rem; }

/* 22 Final CTA */
.final-cta { background: var(--deep-steel); color: var(--mist); padding: var(--space-xl) 0; }.final-grid { display: grid; grid-template-columns: .95fr 1.05fr; gap: clamp(3rem,8vw,8rem); align-items: center; }.final-cta h2 { color: var(--white); margin: .7rem 0 1.3rem; }.final-cta .eyebrow { color: var(--amber); }.cta-field { position: relative; display: grid; grid-template-columns: repeat(4,1fr); gap: 1rem; min-height: 340px; align-items: center; }.mini-spine { position: relative; border-left: 4px solid var(--field-paper); height: 210px; padding: 1rem; writing-mode: vertical-rl; font: .7rem var(--font-mono); text-transform: uppercase; }.mini-spine:nth-of-type(even) { height: 270px; margin-top: 2rem; }.mini-spine::before { content: ""; position: absolute; left: -8px; top: 38%; width: 12px; height: 12px; border: 2px solid var(--amber); border-radius: 50%; background: var(--deep-steel); }.cta-field strong { position: absolute; inset: 48% auto auto 50%; transform: translate(-50%,-50%); background: var(--clay); padding: .5rem .8rem; font: .7rem var(--font-mono); text-transform: uppercase; }.cta-field i { width: 12px; height: 12px; border: 2px solid var(--amber); border-radius: 50%; }

/* 23 Footer */
.site-footer { background: var(--basalt); color: var(--mist); padding: 4rem 0 2rem; }.footer-grid { display: grid; gap: 3rem; }.footer-brand { display: flex; align-items: center; gap: 1.2rem; }.footer-brand img { width: 52px; padding: .3rem; background: var(--field-paper); }.footer-brand strong { color: var(--white); font-family: var(--font-editorial); font-size: 1.5rem; }.footer-brand p { font-size: .82rem; }.footer-brand small { color: var(--muted); }.site-footer nav { display: flex; flex-wrap: wrap; gap: 1.3rem; padding-block: 1.2rem; border-block: 1px solid rgba(255,255,255,.15); }.site-footer nav a,.footer-bottom { font-size: .75rem; }.footer-bottom { display: flex; justify-content: space-between; }.footer-bottom a { font-family: var(--font-mono); }

/* 24 Reveal */
.js-enabled .reveal { opacity: 0; transform: translateY(20px); transition: opacity 650ms ease, transform 650ms ease; }.js-enabled .reveal.is-visible { opacity: 1; transform: none; }

/* 25 Responsive */
@media (max-width: 1080px) {
  .brand { width: 240px; }.menu-toggle { display: block; }.primary-navigation { position: absolute; top: 72px; right: 1.5rem; left: 1.5rem; display: none; flex-direction: column; align-items: stretch; padding: 1rem; background: var(--basalt); box-shadow: var(--shadow); }.primary-navigation.is-open { display: flex; }.primary-navigation a { padding: .55rem; }
  .hero::before { left: 50%; }.hero-grid { grid-template-columns: 50% 50%; }.hero-copy { padding-right: 2.5rem; }.hero-architecture { margin-left: 2.5rem; gap: 2.4rem; }.systems-grid { grid-template-columns: repeat(2,1fr); }.profile-grid { grid-template-columns: repeat(2,1fr); }.method-step:nth-child(n) { grid-column: span 6; }.method-step:last-child { grid-column: 4 / span 6; }.principles-grid { grid-template-columns: repeat(2,1fr); }.principles article:nth-child(2) { border-right: 0; }.principles article:nth-child(-n+2) { border-bottom: var(--border); }
}
@media (max-width: 760px) {
  .container { width: min(calc(100% - 2rem), var(--container)); }.hero::before { inset: 52% 0 0; border-left: 0; border-top: var(--border); }.hero-grid { grid-template-columns: 1fr; }.hero-copy { padding: 5rem 0 4rem; }.hero-architecture { height: 530px; margin: 3rem 0 0 1.5rem; gap: clamp(1.35rem,7vw,3rem); }.hero-architecture > p { right: 1rem; padding-left: 0; }.spine { gap: 3.2rem; }.spine span { font-size: .57rem; }.spine span:nth-of-type(even) { display: none; }
  .signal-grid,.systems-grid,.profile-grid,.notes-grid,.principles-grid { grid-template-columns: 1fr; }.signal-grid span { padding: .8rem 0; border-bottom: 1px solid rgba(255,255,255,.14); }.system-card { min-height: 0; }.interface { grid-template-columns: 1fr; padding: 1.5rem; }.interface .boundary { grid-column: auto; }.interface-two,.interface-three { margin: 0; }.method-step:nth-child(n) { grid-column: 1 / -1; min-height: 0; }.checklist,.independence-grid,.about-grid,.final-grid { grid-template-columns: 1fr; gap: 2.5rem; }.checklist ul { columns: 1; }.independence-grid div:last-child { columns: 1; }.profile-b,.profile-e { margin-top: 0; }.search-panel { grid-template-columns: 1fr; }.search-row { flex-direction: column; }.search-panel > p { grid-row: 2; }.principles article { border-right: 0; border-bottom: var(--border); }.cta-field { min-height: 260px; }.mini-spine { height: 170px; padding-left: .7rem; }.mini-spine:nth-of-type(even) { height: 210px; }.footer-bottom { flex-direction: column; gap: 1rem; }
}
@media (max-width: 380px) { .brand { width: 205px; }.hero-architecture { gap: 1.1rem; }.spine { width: 3.2rem; }.spine b { font-size: .58rem; }.cta-field { gap: .35rem; } }

/* 26 Reduced Motion */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; } *, *::before, *::after { scroll-behavior: auto !important; transition-duration: .01ms !important; animation-duration: .01ms !important; animation-iteration-count: 1 !important; }.js-enabled .reveal { opacity: 1; transform: none; }
}