/* ===========================================================
   Lewis Reeves — portfolio stylesheet
   Single stylesheet, no dependencies. Edit tokens below.
   =========================================================== */

/* Self-hosted IBM Plex — no third-party requests. */
@font-face{font-family:"IBM Plex Sans";src:url("/assets/fonts/ibm-plex-sans-latin-400-normal.woff2") format("woff2");font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:"IBM Plex Sans";src:url("/assets/fonts/ibm-plex-sans-latin-500-normal.woff2") format("woff2");font-weight:500;font-style:normal;font-display:swap}
@font-face{font-family:"IBM Plex Sans";src:url("/assets/fonts/ibm-plex-sans-latin-600-normal.woff2") format("woff2");font-weight:600;font-style:normal;font-display:swap}
@font-face{font-family:"IBM Plex Mono";src:url("/assets/fonts/ibm-plex-mono-latin-400-normal.woff2") format("woff2");font-weight:400;font-style:normal;font-display:swap}
@font-face{font-family:"IBM Plex Mono";src:url("/assets/fonts/ibm-plex-mono-latin-500-normal.woff2") format("woff2");font-weight:500;font-style:normal;font-display:swap}

:root {
  /* Palette — light */
  --bg:        #fcfbf9;
  --bg-raised: #ffffff;
  --bg-sunk:   #f4f2ee;
  --ink:       #16181c;
  --ink-soft:  #4d5560;
  --ink-faint: #7b838f;
  --rule:      #e4e1db;
  --rule-soft: #efece7;
  --accent:    #a4551f;   /* copper */
  --accent-ink:#8c4517;
  --accent-bg: #fbf1e8;
  --flag:      #7a1f1f;
  --flag-bg:   #fdf2f2;
  --flag-rule: #e9c9c9;

  /* Type */
  --sans: "IBM Plex Sans", ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;

  /* Measure */
  --measure: 40rem;
  --wide: 66rem;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg:        #0f1114;
    --bg-raised: #161a1f;
    --bg-sunk:   #14171b;
    --ink:       #e9e7e3;
    --ink-soft:  #a4adb9;
    --ink-faint: #7d8794;
    --rule:      #262b32;
    --rule-soft: #1d2127;
    --accent:    #d98d55;
    --accent-ink:#e8a570;
    --accent-bg: #1e1712;
    --flag:      #e08b8b;
    --flag-bg:   #1d1414;
    --flag-rule: #3a2424;
  }
}

:root[data-theme="dark"] {
  --bg:        #0f1114;
  --bg-raised: #161a1f;
  --bg-sunk:   #14171b;
  --ink:       #e9e7e3;
  --ink-soft:  #a4adb9;
  --ink-faint: #7d8794;
  --rule:      #262b32;
  --rule-soft: #1d2127;
  --accent:    #d98d55;
  --accent-ink:#e8a570;
  --accent-bg: #1e1712;
  --flag:      #e08b8b;
  --flag-bg:   #1d1414;
  --flag-rule: #3a2424;
}

/* ---------- base ---------- */

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

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

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
}

img { max-width: 100%; height: auto; display: block; }

a { color: var(--accent-ink); text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { text-decoration-thickness: 2px; }

h1, h2, h3, h4 { line-height: 1.2; letter-spacing: -0.015em; font-weight: 600; margin: 0 0 .5em; }
h1 { font-size: clamp(2rem, 5vw, 2.75rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.3rem, 3vw, 1.55rem); }
h3 { font-size: 1.075rem; }
p  { margin: 0 0 1.1em; }
ul, ol { margin: 0 0 1.1em; padding-left: 1.25em; }
li { margin-bottom: .35em; }
strong { font-weight: 600; }

::selection { background: var(--accent-bg); }

.skip {
  position: absolute; left: -9999px; top: 0;
  background: var(--accent); color: #fff; padding: .6rem 1rem; z-index: 100;
}
.skip:focus { left: 0; }

:focus-visible { outline: 2px solid var(--accent); outline-offset: 3px; border-radius: 2px; }

/* ---------- layout ---------- */

.wrap { width: 100%; max-width: var(--wide); margin: 0 auto; padding: 0 1.5rem; }
.narrow { max-width: var(--measure); }

section { padding: 3.25rem 0; border-top: 1px solid var(--rule-soft); }
section:first-of-type { border-top: 0; }

.eyebrow {
  font-family: var(--mono);
  font-size: .7rem;
  letter-spacing: .12em;
  text-transform: uppercase;
  color: var(--ink-faint);
  margin: 0 0 1.5rem;
  display: flex; align-items: center; gap: .9rem;
}
.eyebrow::after {
  content: ""; flex: 1; height: 1px; background: var(--rule);
}

/* ---------- site header ---------- */

.topbar {
  position: sticky; top: 0; z-index: 20;
  background: color-mix(in srgb, var(--bg) 88%, transparent);
  backdrop-filter: saturate(140%) blur(8px);
  border-bottom: 1px solid var(--rule-soft);
}
.topbar .wrap {
  display: flex; align-items: center; justify-content: space-between;
  gap: 1rem; min-height: 3.5rem;
}
.topbar .mark {
  font-weight: 600; letter-spacing: -0.02em; text-decoration: none; color: var(--ink);
  font-size: .95rem;
}
.topbar nav { display: flex; gap: 1.25rem; font-size: .875rem; }
.topbar nav a { color: var(--ink-soft); text-decoration: none; }
.topbar nav a:hover { color: var(--accent-ink); }
@media (max-width: 34rem) { .topbar nav a.opt { display: none; } }

/* ---------- hero ---------- */

.hero { padding: 3.5rem 0 3rem; }
.hero-grid {
  display: grid; gap: 2.25rem;
  grid-template-columns: 1fr;
  align-items: start;
}
@media (min-width: 46rem) {
  .hero-grid { grid-template-columns: 1fr 13.5rem; gap: 3rem; }
}
.hero h1 { margin-bottom: .35rem; }
.hero .standfirst {
  font-size: 1.2rem; color: var(--ink-soft); max-width: 34rem; margin-bottom: 1.35rem;
}
.status {
  font-family: var(--mono); font-size: .75rem; letter-spacing: .06em;
  text-transform: uppercase; color: var(--accent-ink);
  background: var(--accent-bg); border: 1px solid var(--rule);
  display: inline-block; padding: .3rem .65rem; border-radius: 999px; margin-bottom: 1.1rem;
}
.portrait {
  width: 100%; aspect-ratio: 4/5; object-fit: cover;
  border-radius: 3px; border: 1px solid var(--rule); background: var(--bg-sunk);
}

.actions { display: flex; flex-wrap: wrap; gap: .65rem; margin-top: .35rem; }
.btn {
  display: inline-flex; align-items: center; gap: .5rem;
  font-size: .9rem; font-weight: 500; text-decoration: none;
  padding: .55rem 1.05rem; border-radius: 3px;
  border: 1px solid var(--accent); color: #fff; background: var(--accent);
  transition: opacity .15s ease;
}
.btn:hover { opacity: .88; }
.btn.ghost { background: transparent; color: var(--ink); border-color: var(--rule); }
.btn.ghost:hover { border-color: var(--accent); color: var(--accent-ink); opacity: 1; }
:root[data-theme="dark"] .btn, :root:not([data-theme="light"]) .btn { color: #14100c; }
@media (prefers-color-scheme: light) { :root:not([data-theme="dark"]) .btn { color: #fff; } }
.btn.ghost { color: var(--ink) !important; }

/* ---------- project cards ---------- */

.cards { display: grid; gap: 1.25rem; grid-template-columns: 1fr; }
@media (min-width: 42rem) { .cards { grid-template-columns: repeat(2, 1fr); } }
@media (min-width: 62rem) { .cards { grid-template-columns: repeat(3, 1fr); } }

.card {
  display: flex; flex-direction: column;
  background: var(--bg-raised);
  border: 1px solid var(--rule);
  border-radius: 4px; overflow: hidden;
  text-decoration: none; color: inherit;
  transition: border-color .15s ease, transform .15s ease;
}
.card:hover { border-color: var(--accent); transform: translateY(-2px); }
.card .thumb {
  aspect-ratio: 16/10; width: 100%; object-fit: cover;
  background: var(--bg-sunk); border-bottom: 1px solid var(--rule);
}
.card .body { padding: 1.1rem 1.15rem 1.25rem; display: flex; flex-direction: column; flex: 1; }
.card .kicker {
  font-family: var(--mono); font-size: .68rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: .5rem;
}
.card h3 { margin-bottom: .4rem; letter-spacing: -0.02em; }
.card p { font-size: .925rem; color: var(--ink-soft); margin-bottom: .9rem; }
.card .more {
  margin-top: auto; font-size: .85rem; font-weight: 500; color: var(--accent-ink);
}

/* ---------- résumé blocks ---------- */

.entry { margin-bottom: 1.9rem; }
.entry:last-child { margin-bottom: 0; }
.entry-head {
  display: flex; flex-wrap: wrap; align-items: baseline; gap: .5rem 1rem;
  margin-bottom: .15rem;
}
.entry-head h3 { margin: 0; }
.entry-head .when {
  font-family: var(--mono); font-size: .78rem; color: var(--ink-faint);
  margin-left: auto;
}
.entry .org { color: var(--ink-soft); font-size: .95rem; margin: 0 0 .55rem; }
.entry ul { margin-bottom: 0; }
.entry li { font-size: .95rem; color: var(--ink-soft); }

.pairs { display: grid; gap: 1.1rem 2rem; grid-template-columns: 1fr; }
@media (min-width: 40rem) { .pairs { grid-template-columns: repeat(2, 1fr); } }
.pairs dt {
  font-family: var(--mono); font-size: .7rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: .3rem;
}
.pairs dd { margin: 0; font-size: .95rem; }

/* ---------- project page ---------- */

.proj-hero { padding: 2.75rem 0 2rem; }
.backlink {
  font-size: .85rem; color: var(--ink-soft); text-decoration: none;
  display: inline-block; margin-bottom: 1.25rem;
}
.backlink:hover { color: var(--accent-ink); }
.proj-hero h1 { font-size: clamp(1.8rem, 4.5vw, 2.4rem); }
.proj-hero .standfirst { font-size: 1.15rem; color: var(--ink-soft); max-width: 38rem; }

.specs {
  display: grid; gap: 1rem 1.75rem;
  grid-template-columns: repeat(auto-fit, minmax(9rem, 1fr));
  border-top: 1px solid var(--rule); border-bottom: 1px solid var(--rule);
  padding: 1.25rem 0; margin: 1.75rem 0 0;
}
.specs dt {
  font-family: var(--mono); font-size: .68rem; letter-spacing: .1em;
  text-transform: uppercase; color: var(--ink-faint); margin-bottom: .25rem;
}
.specs dd { margin: 0; font-size: .9rem; line-height: 1.45; }

.step { padding: 2.5rem 0; border-top: 1px solid var(--rule-soft); }
.step > .wrap > .num {
  font-family: var(--mono); font-size: .7rem; letter-spacing: .12em;
  text-transform: uppercase; color: var(--accent-ink); margin-bottom: .6rem;
}
.step h2 { margin-bottom: 1rem; }
.step .narrow > :last-child { margin-bottom: 0; }

figure { margin: 1.75rem 0; }
figure img { border-radius: 3px; border: 1px solid var(--rule); width: 100%; }
figcaption {
  font-size: .82rem; color: var(--ink-faint); margin-top: .6rem; line-height: 1.5;
}
.gallery { display: grid; gap: 1rem; grid-template-columns: 1fr; margin: 1.75rem 0; }
@media (min-width: 40rem) { .gallery.two { grid-template-columns: repeat(2, 1fr); } }

.datatable { width: 100%; border-collapse: collapse; font-size: .9rem; margin: 1.5rem 0; }
.datatable th, .datatable td { text-align: left; padding: .55rem .75rem; border-bottom: 1px solid var(--rule-soft); }
.datatable th { font-family: var(--mono); font-size: .7rem; letter-spacing: .08em; text-transform: uppercase; color: var(--ink-faint); }
.datatable td.num { font-family: var(--mono); }
.scroll-x { overflow-x: auto; }

.callout {
  border-left: 3px solid var(--accent); background: var(--accent-bg);
  padding: 1rem 1.15rem; border-radius: 0 3px 3px 0; margin: 1.5rem 0;
  font-size: .95rem;
}
.callout > :last-child { margin-bottom: 0; }

/* ---------- footer ---------- */

footer {
  border-top: 1px solid var(--rule);
  padding: 2.5rem 0 3.5rem;
  font-size: .875rem; color: var(--ink-soft);
}
footer .wrap { display: flex; flex-wrap: wrap; gap: 1rem 2rem; justify-content: space-between; }
footer a { color: var(--ink-soft); }
footer .contact { display: flex; flex-wrap: wrap; gap: 1.25rem; }

/* ---------- print ---------- */

@media print {
  :root {
    --bg: #fff; --bg-raised: #fff; --bg-sunk: #fff;
    --ink: #000; --ink-soft: #222; --ink-faint: #555;
    --rule: #bbb; --rule-soft: #ddd; --accent: #000; --accent-ink: #000;
  }
  .topbar, .actions, .card .more, footer .contact { display: none !important; }
  body { font-size: 10.5pt; }
  section, .step { padding: 1rem 0; break-inside: avoid; }
  a { text-decoration: none; color: #000; }
  a[href^="http"]::after { content: " (" attr(href) ")"; font-size: 8pt; color: #555; }
  .card { break-inside: avoid; border-color: #ccc; }
}

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

/* ===========================================================
   Charts — validated two-step copper ramp.
   light #8c4517 / #d08a4e · dark #c08050 / #8f4f22
   Both pass lightness band, chroma, CVD and normal-vision
   separation. The sub-3:1 contrast WARN on the recessive step
   is relieved by direct labels + the table view below each chart.
   Dark steps are selected against the dark surface, not flipped.
   =========================================================== */

:root {
  --chart-1: #8c4517;   /* emphasis */
  --chart-2: #d08a4e;   /* recessive */
  --chart-track: #ece8e2;
  --chart-line: #6b7280;
}
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --chart-1: #c08050; --chart-2: #8f4f22;
    --chart-track: #1e232a; --chart-line: #98a0ac;
  }
}
:root[data-theme="dark"] {
  --chart-1: #c08050; --chart-2: #8f4f22;
  --chart-track: #1e232a; --chart-line: #98a0ac;
}

figure.chart { margin: 2rem 0; }
.chart-title {
  font-size: .95rem; font-weight: 600; margin-bottom: .25rem;
}
.chart-sub {
  font-size: .84rem; color: var(--ink-faint); margin-bottom: 1.25rem; line-height: 1.5;
}

/* --- stacked budget bar --- */
.budget { margin: 0 0 .5rem; }
.budget-track {
  display: flex; align-items: stretch; gap: 2px;
  height: 46px; width: 100%;
}
.budget-seg {
  border-radius: 2px; position: relative;
  display: flex; align-items: center; justify-content: center;
}
.budget-seg:first-child { border-radius: 4px 2px 2px 4px; }
.budget-seg.spare {
  background: repeating-linear-gradient(135deg,
    transparent 0 5px, var(--chart-track) 5px 10px);
  border: 1px dashed var(--rule);
  border-radius: 2px 4px 4px 2px;
}
.budget-seg .v {
  font-family: var(--mono); font-size: .82rem; font-weight: 500; color: #fff;
  white-space: nowrap;
}
:root[data-theme="dark"] .budget-seg .v { color: #14100c; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .budget-seg .v { color: #14100c; }
}
.budget-seg.spare .v { color: var(--ink-faint) !important; }

.budget-key {
  display: flex; flex-wrap: wrap; gap: .35rem 1.4rem; margin-top: .85rem;
  font-size: .85rem; color: var(--ink-soft);
}
.budget-key span { display: inline-flex; align-items: center; gap: .5rem; }
.budget-key i {
  width: 11px; height: 11px; border-radius: 2px; flex: none; display: inline-block;
}

/* --- gauge comparison --- */
.gauges { display: grid; gap: .55rem; margin: 0; }
.gauge-row {
  display: grid; align-items: center; gap: .7rem;
  grid-template-columns: 4.4rem 1fr 3rem 3.6rem;
}
.gauge-row .g {
  font-family: var(--mono); font-size: .84rem; color: var(--ink);
}
.gauge-plot { position: relative; height: 26px; background: var(--chart-track); border-radius: 3px; }
.gauge-bar {
  position: absolute; left: 0; top: 0; bottom: 0;
  border-radius: 2px 4px 4px 2px;
}
.gauge-row .val {
  font-family: var(--mono); font-size: .8rem; text-align: right; color: var(--ink-soft);
  white-space: nowrap;
}
.gauge-row .verdict {
  font-size: .78rem; color: var(--ink-faint); white-space: nowrap;
}
.gauge-row.chosen .verdict { color: var(--accent-ink); font-weight: 500; }
.gauge-row.chosen .g,
.gauge-row.chosen .val { color: var(--ink); font-weight: 500; }
.limit {
  position: absolute; top: -6px; bottom: -6px; width: 0;
  border-left: 2px dashed var(--chart-line);
}
.limit-note {
  display: grid; grid-template-columns: 4.4rem 1fr 3rem 3.6rem; gap: .7rem;
  margin-top: .5rem; font-size: .78rem; color: var(--ink-faint);
}
.limit-note .mark { position: relative; height: 1em; }
.limit-note .mark span {
  position: absolute; transform: translateX(-50%); white-space: nowrap;
  font-family: var(--mono);
}
@media (max-width: 32rem) {
  .gauge-row   { grid-template-columns: 3.5rem 1fr 2.6rem 3.2rem; gap: .5rem; }
  .limit-note  { grid-template-columns: 3.5rem 1fr 2.6rem 3.2rem; gap: .5rem; }
  .gauge-row .g, .gauge-row .val { font-size: .72rem; }
  .gauge-row .verdict, .limit-note { font-size: .68rem; }
}

/* --- schematic sits on its own light panel in both themes --- */
.schematic {
  background: #f4f2ec; border: 1px solid var(--rule);
  border-radius: 4px; padding: 1.25rem; margin: 0;
}
.schematic img { width: 100%; max-width: 30rem; margin: 0 auto; border: 0; }

/* --- worked calculation --- */
.calc {
  border-left: 3px solid var(--rule); padding: .25rem 0 .25rem 1.15rem;
  margin: 1.5rem 0; display: grid; gap: .85rem;
}
.calc-step { display: grid; gap: .2rem; }
.calc-step .lbl { font-size: .88rem; color: var(--ink-soft); }
.calc-step .expr {
  font-family: var(--mono); font-size: .88rem; color: var(--ink);
  overflow-x: auto; padding-bottom: .15rem;
}
.calc-step .expr b { font-weight: 500; color: var(--accent-ink); }

/* Cards without a write-up yet: visibly pending, not a dead link. */
.card:not(a) { border-style: dashed; }
.card:not(a):hover { transform: none; border-color: var(--rule); }
.card:not(a) .more { color: var(--ink-faint); font-weight: 400; }
.card:not(a) .body { padding-top: 1.25rem; }