/* ==========================================================================
   The Vitruvian Protocol
   Pen, ink and watercolor over metalpoint on paper.
   ========================================================================== */

@view-transition { navigation: auto; }

:root {
  --paper: #efe4cb;
  --paper-deep: #e4d4b2;
  --ink: #3b2a1c;
  --ink-soft: #6a5442;
  --ink-faint: rgba(59, 42, 28, 0.22);
  --metal: #8f877c;
  --rule: rgba(59, 42, 28, 0.28);
  --pig: #8a5a3a;
  --pig-ink: #5a3a22;

  --display: "Cormorant Garamond", "Cormorant", Garamond, "Times New Roman", serif;
  --text: "EB Garamond", Garamond, "Times New Roman", serif;

  --ease: cubic-bezier(.65, 0, .25, 1);
  --gutter: clamp(16px, 4vw, 56px);
  color-scheme: light;
}

*, *::before, *::after { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; }

body {
  margin: 0;
  min-height: 100svh;
  background-color: var(--paper);
  background-image:
    radial-gradient(ellipse 120% 90% at 50% 45%, transparent 55%, rgba(120, 82, 40, 0.16) 100%),
    radial-gradient(circle at 12% 18%, rgba(150, 100, 50, 0.07) 0 3px, transparent 18px),
    radial-gradient(circle at 86% 74%, rgba(150, 100, 50, 0.06) 0 2px, transparent 14px),
    radial-gradient(circle at 72% 12%, rgba(150, 100, 50, 0.05) 0 2px, transparent 12px),
    radial-gradient(circle at 22% 88%, rgba(150, 100, 50, 0.06) 0 3px, transparent 20px),
    linear-gradient(170deg, #f2e8d1 0%, var(--paper) 45%, var(--paper-deep) 100%);
  background-attachment: fixed;
  color: var(--ink);
  font-family: var(--text);
  font-size: clamp(17px, 1.05vw + 10px, 19px);
  line-height: 1.6;
  font-variant-numeric: oldstyle-nums;
  text-rendering: optimizeLegibility;
  -webkit-font-smoothing: antialiased;
}

/* paper grain */
body::after {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 50;
  opacity: 0.3;
  mix-blend-mode: multiply;
  background-image: url("../assets/paper-grain.svg");
  background-size: 320px 320px;
}

::selection { background: rgba(192, 67, 47, 0.22); }

a { color: inherit; }

:focus-visible {
  outline: 1.5px solid var(--ink);
  outline-offset: 4px;
  border-radius: 2px;
}

.skip {
  position: absolute; left: -9999px; top: 8px;
  background: var(--paper); padding: 6px 12px; z-index: 100;
}
.skip:focus { left: 8px; }

/* -------------------------------------------------------------- type */
.eyebrow {
  font-family: var(--text);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin: 0 0 0.9rem;
}

h1, h2, h3 {
  font-family: var(--display);
  font-weight: 400;
  line-height: 1.08;
  margin: 0;
  letter-spacing: -0.005em;
}

.rule {
  border: 0;
  height: 1px;
  background: linear-gradient(90deg, transparent, var(--rule) 12%, var(--rule) 88%, transparent);
  margin: 2.5rem 0;
}

.mirror {
  font-family: var(--display);
  font-style: italic;
  font-size: 0.86rem;
  line-height: 1.3;
  color: var(--ink-soft);
  opacity: 0.55;
  transform: scaleX(-1);
  text-align: center;
  margin: 0;
  user-select: none;
}

/* -------------------------------------------------------------- site bar */
.bar {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 1rem;
  padding: 22px var(--gutter) 0;
  position: relative;
  z-index: 5;
}
.mark {
  font-family: var(--display);
  font-size: 1.05rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  text-decoration: none;
  font-weight: 500;
}
.mark small { font-size: 0.7em; letter-spacing: 0.2em; color: var(--ink-soft); font-weight: 400; }
.bar nav { display: flex; gap: 1.6rem; font-size: 0.9rem; }
.bar nav a { text-decoration: none; color: var(--ink-soft); }
.bar nav a:hover { color: var(--ink); text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 1px; }

/* -------------------------------------------------------------- the figure */
.figure { aspect-ratio: 1; width: 100%; position: relative; view-transition-name: vitruvian; }
.vm { display: block; width: 100%; height: 100%; overflow: visible; }

.vm .metal { fill: none; stroke: var(--metal); stroke-width: 0.45; opacity: 0.55; }
.vm .ink path { fill: none; stroke: var(--ink); stroke-linecap: round; stroke-linejoin: round; }
.vm .ink .fine { stroke: var(--ink-soft); }
.vm .alt path { stroke: var(--ink-soft); }
.vm .ink-all > g { transition: opacity .45s var(--ease); }

.vm .sys { opacity: 0; transition: opacity .45s var(--ease); pointer-events: none; }
.vm .sys.on { opacity: 1; }
.vm .wash { mix-blend-mode: multiply; }
.vm .w-fill { fill: var(--pig); stroke: none; }
.vm .w-line { fill: none; stroke: var(--pig); stroke-linecap: round; stroke-linejoin: round; }
.vm .marks path { fill: none; stroke: var(--pig-ink); stroke-linecap: round; stroke-linejoin: round; }
.vm .l-shape { stroke-width: 0.75; }
.vm .l-skin { stroke-width: 1.6; opacity: 0.8; }
.vm .l-dash { stroke-width: 0.8; stroke-dasharray: 3 3; }

.vm.has-active .body { opacity: 0.38; }
.vm.has-active .alt { opacity: 0.16; }
.vm.has-active .frame { opacity: 0.55; }

.vm .hits path { fill: transparent; stroke: transparent; pointer-events: all; cursor: pointer; }
.vm .hits .h-line { fill: none; stroke-width: 10; pointer-events: stroke; }
.vm .hits .h-fill { stroke-width: 3; }

/* ink drawing itself in on first visit */
.vm.drawing .ink path[pathLength] {
  stroke-dasharray: 1;
  stroke-dashoffset: 1;
  animation: vm-draw 1.6s var(--ease) forwards;
  animation-delay: calc(var(--i) * 45ms);
}
.vm.drawing .frame path[pathLength] { animation-duration: 2.2s; animation-delay: 0s; }
.vm.drawing .ink .fine { opacity: 0; animation: vm-fade 1.2s ease forwards; animation-delay: 1.8s; }
.vm.drawing .metal { opacity: 0; animation: vm-metal 2.4s ease forwards; }
@keyframes vm-draw { to { stroke-dashoffset: 0; } }
@keyframes vm-fade { to { opacity: 1; } }
@keyframes vm-metal { to { opacity: 0.55; } }

/* -------------------------------------------------------------- home */
.home {
  display: grid;
  grid-template-columns: minmax(220px, 1fr) minmax(0, min(78svh, 50vw)) minmax(250px, 1fr);
  align-items: center;
  gap: clamp(16px, 3vw, 56px);
  padding: 8px var(--gutter) 24px;
  min-height: calc(100svh - 60px);
}

.intro { align-self: center; max-width: 23rem; }
.intro h1 {
  font-size: clamp(2.6rem, 4.2vw, 4.4rem);
  font-weight: 300;
  line-height: 0.98;
}
.intro h1 em { font-style: italic; display: block; }
.intro .thesis { margin: 1.4rem 0 0; color: var(--ink); max-width: 21rem; }
.intro .hint {
  margin: 1.6rem 0 0;
  font-style: italic;
  color: var(--ink-soft);
  font-size: 0.92rem;
  padding-left: 1rem;
  border-left: 1px solid var(--rule);
}

.stage { display: flex; flex-direction: column; gap: 6px; }

.systems-nav h2 {
  font-family: var(--text);
  font-size: 0.72rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  margin: 0 0 0.6rem;
  font-weight: 400;
}
.systems-nav ol { list-style: none; margin: 0; padding: 0; }
.systems-nav li { position: relative; }
.systems-nav a {
  --pig: transparent;
  display: grid;
  grid-template-columns: 2.6rem 1fr;
  align-items: baseline;
  padding: 0.34rem 0.5rem 0.34rem 0;
  text-decoration: none;
  position: relative;
  isolation: isolate;
}
.systems-nav a::before {
  /* watercolor dab behind the active item */
  content: "";
  position: absolute;
  inset: 8% -6% 8% 1.8rem;
  z-index: -1;
  background:
    radial-gradient(ellipse 60% 70% at 30% 50%, var(--pig), transparent 70%),
    radial-gradient(ellipse 50% 60% at 70% 55%, var(--pig), transparent 72%);
  opacity: 0;
  filter: blur(6px);
  transition: opacity .35s var(--ease);
}
.systems-nav .num {
  font-family: var(--display);
  font-size: 0.95rem;
  color: var(--ink-soft);
  letter-spacing: 0.04em;
  text-align: right;
  padding-right: 0.9rem;
}
.systems-nav .name {
  font-family: var(--display);
  font-size: clamp(1.15rem, 1.25vw, 1.4rem);
  line-height: 1.15;
  transition: color .3s var(--ease), letter-spacing .3s var(--ease);
}
.systems-nav .sub {
  grid-column: 2;
  font-size: 0.8rem;
  font-style: italic;
  color: var(--ink-soft);
  line-height: 1.3;
}
.systems-nav .go {
  display: none;
  grid-column: 2;
  font-size: 0.78rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--pig-ink);
  margin-top: 0.15rem;
}
.systems-nav a.active::before { opacity: 0.32; }
.systems-nav a.active .name { color: var(--pig-ink); }
.systems-nav a.active .num { color: var(--pig-ink); }
.systems-nav a.armed .go { display: block; }

/* leader line from list to organ */
.leader {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 4;
  overflow: visible;
}
.leader path {
  fill: none;
  stroke: var(--pig-ink, var(--ink));
  stroke-width: 0.7;
  stroke-dasharray: 1;
  stroke-dashoffset: 1;
  opacity: 0.7;
}
.leader circle { fill: none; stroke: var(--pig-ink, var(--ink)); stroke-width: 0.8; opacity: 0; }
.leader.show path { animation: vm-draw .55s var(--ease) forwards; }
.leader.show circle { animation: vm-fade .3s ease .45s forwards; }

/* -------------------------------------------------------------- foundations */
.section {
  padding: clamp(48px, 8vw, 110px) var(--gutter);
  max-width: 1180px;
  margin: 0 auto;
}
.section-head { display: grid; grid-template-columns: 1fr 2fr; gap: 2rem; align-items: end; margin-bottom: 2.5rem; }
.section-head h2 { font-size: clamp(2rem, 3.4vw, 3rem); font-weight: 300; }
.section-head p { margin: 0; color: var(--ink-soft); max-width: 36rem; }

.levers {
  list-style: none; margin: 0; padding: 0;
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  border-top: 1px solid var(--rule);
}
.levers li { padding: 1.4rem 1.2rem 0 0; }
.levers li + li { padding-left: 1.2rem; border-left: 1px solid var(--rule); }
.levers .n { font-family: var(--display); color: var(--ink-soft); font-size: 0.95rem; }
.levers h3 { font-size: 1.45rem; margin: 0.3rem 0 0.5rem; }
.levers p { margin: 0; font-size: 0.92rem; color: var(--ink); }

.grades { display: grid; grid-template-columns: repeat(3, 1fr); gap: 0; border-top: 1px solid var(--rule); }
.grades > div { padding: 1.4rem 1.2rem 0 0; }
.grades > div + div { padding-left: 1.2rem; border-left: 1px solid var(--rule); }
.grades h3 { font-size: 1.35rem; margin: 0.6rem 0 0.4rem; }
.grades p { margin: 0; font-size: 0.92rem; }

/* -------------------------------------------------------------- footer */
.foot {
  padding: 2rem var(--gutter) 2.5rem;
  border-top: 1px solid var(--rule);
  display: flex; flex-wrap: wrap; gap: 1rem 2rem; justify-content: space-between;
  font-size: 0.85rem; color: var(--ink-soft);
  max-width: 1180px; margin: 0 auto;
}
.foot p { margin: 0; max-width: 46rem; }

/* -------------------------------------------------------------- grade dots */
.grade { display: inline-flex; align-items: center; gap: 0.5rem; font-size: 0.82rem; letter-spacing: 0.06em; color: var(--ink-soft); white-space: nowrap; }
.dots { display: inline-flex; gap: 4px; }
.dots i {
  width: 9px; height: 9px; border-radius: 50%;
  border: 1px solid var(--ink);
  background: transparent;
  display: block;
}
.dots i.f { background: radial-gradient(circle at 40% 38%, #5a4230, var(--ink) 70%); }

/* -------------------------------------------------------------- system page */
.sys-page {
  display: grid;
  grid-template-columns: minmax(300px, 42%) minmax(0, 1fr);
  gap: clamp(24px, 5vw, 88px);
  padding: 0 var(--gutter);
  max-width: 1440px;
  margin: 0 auto;
}
.plate {
  position: sticky;
  top: 0;
  height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  padding: 72px 0 32px;
}
.plate .figure { max-width: min(520px, 72svh); margin: 0 auto; }
.plate figcaption {
  text-align: center;
  font-style: italic;
  color: var(--ink-soft);
  font-size: 0.9rem;
  max-width: 24rem;
  margin: 0.4rem auto 0;
}

.reading { padding: clamp(40px, 10svh, 120px) 0 64px; max-width: 40rem; }
.reading .sys-num { font-family: var(--display); font-size: 1.1rem; letter-spacing: 0.14em; color: var(--pig-ink); }
.reading h1 {
  font-size: clamp(2.8rem, 5vw, 4.8rem);
  font-weight: 300;
  margin: 0.2rem 0 0.4rem;
  view-transition-name: sys-title;
  width: fit-content;
}
.reading .sub { font-style: italic; color: var(--ink-soft); font-size: 1.1rem; margin: 0; }

.reading h2 {
  font-family: var(--text);
  font-size: 0.74rem;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--ink-soft);
  font-weight: 400;
  margin: 3rem 0 1rem;
  display: flex; align-items: center; gap: 1rem;
}
.reading h2::after { content: ""; flex: 1; height: 1px; background: var(--rule); }
.reading p { margin: 0 0 1rem; }

.lede { font-size: 1.12em; }
.lede::first-letter {
  font-family: var(--display);
  float: left;
  font-size: 3.6em;
  line-height: 0.82;
  padding: 0.06em 0.12em 0 0;
  color: var(--pig-ink);
}

.protocol { position: relative; padding: 1.5rem 0 0.5rem; }
.protocol::before {
  /* faint wash behind the protocol's title */
  content: "";
  position: absolute;
  left: -1.2rem; top: 0.6rem;
  width: 62%; height: 5.5rem;
  background: radial-gradient(ellipse 70% 60% at 30% 50%, var(--pig), transparent 72%);
  opacity: 0.16;
  filter: blur(10px);
  z-index: -1;
}
.protocol .p-label { font-size: 0.74rem; letter-spacing: 0.2em; text-transform: uppercase; color: var(--pig-ink); }
.protocol h3 { font-size: clamp(1.7rem, 2.6vw, 2.25rem); line-height: 1.12; margin: 0.4rem 0 0.8rem; font-weight: 400; }
.protocol dl { margin: 1.2rem 0 0; }
.protocol dt {
  font-family: var(--display);
  font-style: italic;
  font-size: 1.12rem;
  color: var(--pig-ink);
  margin-top: 1.1rem;
}
.protocol dd { margin: 0.15rem 0 0; }
.protocol dd ul { margin: 0.3rem 0 0; padding-left: 1.1rem; }
.protocol dd li { margin: 0.2rem 0; }
.protocol dd li::marker { color: var(--pig-ink); }

sup { line-height: 0; font-size: 0.7em; }
sup a { text-decoration: none; color: var(--pig-ink); padding: 0 1px; }
sup a:hover { text-decoration: underline; }

.measures { list-style: none; margin: 0; padding: 0; }
.measures li {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.2rem 1.5rem;
  padding: 0.7rem 0;
  border-bottom: 1px solid var(--rule);
}
.measures li:first-child { border-top: 1px solid var(--rule); }
.measures b { font-weight: 500; }
.measures .target { font-family: var(--display); font-size: 1.15rem; color: var(--pig-ink); text-align: right; }
.measures .note { grid-column: 1 / -1; font-size: 0.88rem; color: var(--ink-soft); }

.avoid { list-style: none; margin: 0; padding: 0; }
.avoid li { padding-left: 1.6rem; position: relative; margin: 0 0 0.9rem; }
.avoid li::before {
  content: "";
  position: absolute; left: 0.1rem; top: 0.75em;
  width: 0.85rem; height: 1px;
  background: var(--ink);
  transform: rotate(-8deg);
}

.sources { padding-left: 1.4rem; font-size: 0.86rem; color: var(--ink-soft); }
.sources li { margin: 0 0 0.6rem; padding-left: 0.3rem; }
.sources li:target { color: var(--ink); background: linear-gradient(90deg, rgba(192, 67, 47, 0.08), transparent); }
.sources a { color: var(--ink-soft); word-break: break-word; }

.pager {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  gap: 1rem;
  align-items: center;
  margin-top: 3.5rem;
  padding-top: 1.4rem;
  border-top: 1px solid var(--rule);
  font-size: 0.92rem;
}
.pager a { text-decoration: none; }
.pager a:hover .pn { text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 1px; }
.pager .next { text-align: right; }
.pager small { display: block; font-size: 0.72rem; letter-spacing: 0.18em; text-transform: uppercase; color: var(--ink-soft); }
.pager .pn { font-family: var(--display); font-size: 1.25rem; }
.pager .home-link { font-style: italic; color: var(--ink-soft); }

.disclaimer { font-size: 0.82rem; color: var(--ink-soft); margin-top: 2.2rem; font-style: italic; }

/* -------------------------------------------------------------- 404 */
.lost {
  display: grid;
  grid-template-columns: minmax(0, 360px) minmax(0, 28rem);
  gap: clamp(24px, 5vw, 72px);
  align-items: center;
  justify-content: center;
  min-height: calc(100svh - 70px);
  padding: 24px var(--gutter);
}
.lost h1 { font-size: clamp(2.4rem, 5vw, 3.6rem); font-weight: 300; margin-bottom: 1rem; }
.lost .vm .body { opacity: 0.5; }
@media (max-width: 820px) { .lost { grid-template-columns: 1fr; } .lost-figure { max-width: 260px; } }

/* -------------------------------------------------------------- transitions */
::view-transition-group(vitruvian),
::view-transition-group(sys-title) {
  animation-duration: .75s;
  animation-timing-function: var(--ease);
}
::view-transition-old(vitruvian),
::view-transition-new(vitruvian) {
  height: 100%;
  animation-duration: .75s;
  animation-timing-function: var(--ease);
}
::view-transition-old(root) { animation: vt-out .35s ease both; }
::view-transition-new(root) { animation: vt-in .55s ease .15s both; }
@keyframes vt-out { to { opacity: 0; filter: blur(2px); } }
@keyframes vt-in { from { opacity: 0; transform: translateY(8px); } }

/* fallback for browsers without cross-document view transitions */
.no-vt body { animation: page-in .55s ease both; }
.no-vt body.leaving { animation: page-out .34s ease both; }
@keyframes page-in { from { opacity: 0; } }
@keyframes page-out { to { opacity: 0; transform: scale(1.015); filter: blur(1.5px); } }

/* -------------------------------------------------------------- responsive */
@media (max-width: 1100px) {
  .home { grid-template-columns: minmax(0, 1fr) minmax(250px, 34%); grid-template-areas: "intro intro" "stage list"; }
  .intro { grid-area: intro; max-width: 40rem; padding-top: 1.5rem; }
  .stage { grid-area: stage; }
  .systems-nav { grid-area: list; }
  .levers { grid-template-columns: repeat(2, 1fr); }
  .levers li, .levers li + li { padding: 1.2rem 1rem 1.2rem 0; border-left: 0; border-bottom: 1px solid var(--rule); }
}

@media (max-width: 820px) {
  body { font-size: 17px; }
  .bar nav { gap: 1rem; }
  .bar { padding-top: 16px; }
  .mark { font-size: 0.82rem; letter-spacing: 0.12em; }
  /* phone: title, then the figure and the systems together, then the thesis */
  .home { display: flex; flex-direction: column; align-items: stretch; gap: 0; min-height: 0; padding-top: 18px; padding-bottom: 8px; }
  .intro { display: contents; }
  .intro .eyebrow { order: 1; margin-bottom: 0.4rem; }
  .intro h1 { order: 2; font-size: clamp(1.9rem, 9vw, 2.6rem); }
  .intro h1 em { display: inline; }
  .stage { order: 3; margin: 0.4rem -6px 0; }
  .stage .mirror { display: none; }
  .stage .figure { width: min(100%, 76vw, 46svh); margin: 0 auto; }
  .systems-nav { order: 4; }
  .intro .thesis { order: 5; margin-top: 1.8rem; max-width: none; }
  .intro .hint { order: 6; }
  .systems-nav h2 { margin-bottom: 0.3rem; }
  .systems-nav ol { display: grid; grid-template-columns: 1fr 1fr; column-gap: 0.4rem; }
  .systems-nav a { grid-template-columns: 1.9rem 1fr; padding: 0.28rem 0.2rem 0.28rem 0; }
  .systems-nav .num { padding-right: 0.45rem; font-size: 0.8rem; }
  .systems-nav .name { font-size: 1.08rem; }
  .systems-nav .sub { display: none; }
  .systems-nav a.armed .go { font-size: 0.66rem; }
  .leader { display: none; }
  .section-head { grid-template-columns: 1fr; gap: 0.8rem; }
  .levers { grid-template-columns: 1fr; }
  .grades { grid-template-columns: 1fr; }
  .grades > div, .grades > div + div { padding: 1.2rem 0; border-left: 0; border-bottom: 1px solid var(--rule); }

  .sys-page { grid-template-columns: 1fr; gap: 0; }
  .plate { position: relative; height: auto; padding: 16px 0 0; }
  .plate .figure { max-width: 300px; }
  .reading { padding-top: 16px; }
  .pager { grid-template-columns: 1fr 1fr; }
  .pager .home-link { grid-column: 1 / -1; grid-row: 2; text-align: center; }
}

@media (max-width: 420px) {
  .bar nav a.opt { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation-duration: 0.01ms !important; animation-delay: 0s !important; transition-duration: 0.01ms !important; }
  ::view-transition-group(*), ::view-transition-old(*), ::view-transition-new(*) { animation: none !important; }
}

@media print {
  body::after, .plate, .bar nav, .pager { display: none; }
  .sys-page { display: block; }
}