/* Layout: left-aligned editorial column on a 12-col grid; the 85% statistic is the hero, yellow "highlighter" is the only accent. */
:root {
  --paper: #fbfbf9;
  --paper-2: #f1f1ed;
  --ink: #111318;
  --muted: #5a5e67;
  --rule: #d9dad5;
  --spark: #ffd43b;
  --on-spark: #111318;

  --display: "Playfair Display", "Times New Roman", Georgia, serif;
  --body: "Instrument Sans", "Helvetica Neue", Arial, sans-serif;
  --mono: "IBM Plex Mono", ui-monospace, "SFMono-Regular", Menlo, monospace;

  --step--1: 0.8125rem;
  --step-0: 1.0625rem;
  --step-1: 1.25rem;
  --step-2: clamp(1.5rem, 1.2rem + 1.2vw, 2rem);
  --step-3: clamp(2rem, 1.4rem + 2.6vw, 3.25rem);
  --step-4: clamp(2.75rem, 1.6rem + 5.4vw, 6rem);

  --wrap: 1180px;
  --gutter: max(16px, env(safe-area-inset-left, 0px));
  --gutter-r: max(16px, env(safe-area-inset-right, 0px));
}

*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }
body {
  margin: 0;
  background: var(--paper);
  color: var(--ink);
  font: 400 var(--step-0)/1.6 var(--body);
  -webkit-font-smoothing: antialiased;
}
img { max-width: 100%; display: block; }
a { color: inherit; }
:focus-visible { outline: 3px solid var(--spark); outline-offset: 3px; border-radius: 2px; }
h1, h2, h3 { margin: 0; text-wrap: balance; }
p { margin: 0; }

.wrap {
  max-width: calc(var(--wrap) + 64px);
  margin-inline: auto;
  padding-left: var(--gutter);
  padding-right: var(--gutter-r);
}
@media (min-width: 720px) {
  .wrap { padding-left: max(32px, env(safe-area-inset-left, 0px)); padding-right: max(32px, env(safe-area-inset-right, 0px)); }
}

.label {
  font: 500 var(--step--1)/1.3 var(--mono);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--muted);
}
.hl {
  color: var(--on-spark);
  background: linear-gradient(var(--spark), var(--spark)) no-repeat 0 62% / 100% 78%;
  padding-inline: 0.06em;
  -webkit-box-decoration-break: clone; box-decoration-break: clone;
}

/* Header */
.site-header {
  position: sticky; top: env(safe-area-inset-top, 0px); z-index: 10;
  background: color-mix(in srgb, var(--paper) 88%, transparent);
  backdrop-filter: saturate(1.4) blur(10px);
  -webkit-backdrop-filter: saturate(1.4) blur(10px);
  border-bottom: 1px solid var(--rule);
}
.site-header .wrap { display: flex; align-items: center; justify-content: space-between; gap: 24px; padding-block: 14px; }
.brand { display: inline-flex; text-decoration: none; }
.brand-mark {
  display: block; width: 116px; aspect-ratio: 538 / 120; max-width: 100%;
  background: var(--ink);
  -webkit-mask: url("img/sparksfly.png") center / contain no-repeat;
  mask: url("img/sparksfly.png") center / contain no-repeat;
}
.nav { display: flex; align-items: center; gap: clamp(14px, 3vw, 32px); font-size: 0.95rem; font-weight: 500; }
.nav a { text-decoration: none; }
.nav a:not(.btn):hover { text-decoration: underline; text-underline-offset: 4px; text-decoration-thickness: 2px; text-decoration-color: var(--spark); }
.nav .hide-sm { display: none; }
@media (min-width: 640px) { .nav .hide-sm { display: inline; } }

.btn {
  display: inline-flex; align-items: center; gap: 0.5em;
  padding: 0.6em 1.05em;
  border-radius: 999px;
  background: var(--ink); color: var(--paper);
  font: 600 0.95rem/1 var(--body);
  text-decoration: none; border: 0; cursor: pointer;
  transition: transform .15s ease;
}
.btn:hover { transform: translateY(-1px); }
.btn-lg { padding: 0.95em 1.4em; font-size: 1.02rem; }
.arrow { transition: transform .2s ease; }
a:hover .arrow { transform: translateX(3px); }

/* Hero */
.hero { padding-block: clamp(56px, 10vw, 128px) clamp(40px, 6vw, 72px); }
.hero h1 {
  font: 900 var(--step-4)/1.02 var(--display);
  letter-spacing: -0.02em;
  max-width: 14ch;
}
.hero h1 .quiet { display: block; font-weight: 400; font-style: italic; letter-spacing: -0.01em; color: var(--muted); margin-top: 0.12em; }
.hero-foot {
  margin-top: clamp(28px, 4vw, 48px);
  display: grid; gap: 24px; align-items: end;
}
.hero-foot p { font-size: var(--step-1); max-width: 36ch; }
@media (min-width: 860px) { .hero-foot { grid-template-columns: 1fr auto; } }

@media (prefers-reduced-motion: no-preference) {
  .hero .hl { animation: swipe 0.9s cubic-bezier(.2,.7,.2,1) 0.25s both; }
  @keyframes swipe { from { background-size: 0% 78%; } to { background-size: 100% 78%; } }
}

/* Clients */
.clients { border-block: 1px solid var(--rule); padding-block: 28px; }
.clients .wrap { display: grid; gap: 18px; }
.logo-row {
  list-style: none; margin: 0; padding: 0;
  display: flex; flex-wrap: wrap; align-items: center;
  column-gap: clamp(28px, 5vw, 56px); row-gap: 22px;
}
.logo {
  display: block; height: var(--h, 30px); aspect-ratio: var(--ar);
  max-width: 100%;
  background: var(--ink); opacity: 0.78;
  -webkit-mask: var(--src) center / contain no-repeat;
  mask: var(--src) center / contain no-repeat;
}

/* Sections */
section.block { padding-block: clamp(64px, 9vw, 120px); }
.section-head { display: grid; gap: 14px; margin-bottom: clamp(32px, 5vw, 56px); max-width: 720px; }
.section-head h2 { font: 700 var(--step-3)/1.08 var(--display); letter-spacing: -0.015em; }
.section-head p { color: var(--muted); font-size: var(--step-1); max-width: 52ch; }

/* Services: the real sequence */
.steps { list-style: none; margin: 0; padding: 0; display: grid; gap: 0; counter-reset: step; }
.step {
  display: grid; gap: 10px 32px;
  grid-template-columns: 3.2rem 1fr;
  padding-block: 26px; border-top: 1px solid var(--rule);
}
.step:last-child { border-bottom: 1px solid var(--rule); }
.step .n { font: 500 var(--step--1)/2.1 var(--mono); color: var(--muted); }
.step .phase { grid-column: 2; }
.step h3 { grid-column: 2; font: 600 var(--step-2)/1.15 var(--body); letter-spacing: -0.01em; }
.step p { grid-column: 2; color: var(--muted); max-width: 54ch; }
@media (min-width: 900px) {
  .step { grid-template-columns: 4rem 8rem minmax(0, 20rem) minmax(0, 1fr); align-items: baseline; }
  .step .phase, .step h3, .step p { grid-column: auto; }
}

/* Case studies */
.cases { display: grid; gap: 0; }
.case {
  display: grid; gap: 14px 40px;
  padding-block: clamp(28px, 4vw, 44px);
  border-top: 1px solid var(--rule);
  text-decoration: none; color: inherit;
}
.cases .case:last-child { border-bottom: 1px solid var(--rule); }
.case > div { display: grid; gap: 8px; align-content: start; }
.case h3 { font: 700 var(--step-2)/1.15 var(--display); }
.case .summary { color: var(--muted); max-width: 46ch; }
.case .proof { font: 900 var(--step-3)/1 var(--display); letter-spacing: -0.02em; }
.case .proof-label { color: var(--muted); font-size: 0.95rem; margin-top: 6px; max-width: 26ch; }
.case .more { font-weight: 600; font-size: 0.95rem; display: inline-flex; gap: 0.4em; }
.case:hover h3 span { background: linear-gradient(var(--spark), var(--spark)) no-repeat 0 85% / 100% 30%; color: var(--ink); }
@media (min-width: 900px) {
  .case { grid-template-columns: minmax(0, 1.25fr) minmax(0, 1fr) auto; align-items: start; }
  .case .more { align-self: end; }
}

/* Quote */
.quote { background: var(--paper-2); }
.quote figure { margin: 0; display: grid; gap: 28px; max-width: 980px; }
.quote blockquote { margin: 0; font: 400 var(--step-3)/1.18 var(--display); letter-spacing: -0.01em; }
.quote blockquote::before { content: "\201C"; }
.quote blockquote::after { content: "\201D"; }
.quote figcaption { display: grid; gap: 2px; }
.quote figcaption strong { font-weight: 600; }
.quote figcaption span { color: var(--muted); }

/* Model */
.model { display: grid; gap: 40px; }
.model .copy { display: grid; gap: 18px; max-width: 58ch; font-size: var(--step-1); }
.model .copy p:not(:first-child) { color: var(--muted); font-size: var(--step-0); }
.model .copy p.punch { color: var(--ink); font: 700 var(--step-2)/1.2 var(--display); }
.stat { border-top: 2px solid var(--ink); padding-top: 18px; display: grid; gap: 8px; align-content: start; }
.stat p.big { color: var(--ink);  font: 900 var(--step-4)/0.95 var(--display); letter-spacing: -0.03em; font-variant-numeric: lining-nums; }
.stat p { color: var(--muted); max-width: 30ch; }
@media (min-width: 900px) { .model { grid-template-columns: minmax(0, 1.4fr) minmax(0, 1fr); gap: 80px; } }

/* Contact */
.contact { background: var(--ink); color: var(--paper); }
.contact .label { color: color-mix(in srgb, var(--paper) 65%, transparent); }
.contact .wrap { padding-block: clamp(64px, 9vw, 112px); display: grid; gap: 22px; }
.contact h2 { font: 900 var(--step-3)/1.05 var(--display); max-width: 18ch; }
.email-row { display: flex; flex-wrap: wrap; align-items: center; gap: 14px 20px; margin-top: 10px; }
.email {
  font: 600 clamp(1.25rem, 0.9rem + 2.2vw, 2.25rem)/1.2 var(--body);
  text-decoration: none; overflow-wrap: anywhere;
  background: linear-gradient(var(--spark), var(--spark)) no-repeat 0 100% / 100% 3px;
  padding-bottom: 4px;
}
.copy-btn {
  font: 600 0.9rem/1 var(--body); cursor: pointer;
  padding: 0.6em 1em; border-radius: 999px;
  background: transparent; color: inherit;
  border: 1px solid color-mix(in srgb, var(--paper) 40%, transparent);
}
.copy-btn:hover { border-color: var(--spark); }

/* Footer */
.site-footer { padding-block: 28px; font-size: 0.9rem; color: var(--muted); }
.site-footer .wrap { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 12px; }
.site-footer a { text-decoration: none; }

/* Case study page */
.cs-hero { padding-block: clamp(40px, 7vw, 96px) clamp(32px, 5vw, 56px); display: grid; gap: 22px; }
.back { font-weight: 600; font-size: 0.95rem; text-decoration: none; display: inline-flex; gap: 0.4em; width: fit-content; }
.back:hover .arrow { transform: translateX(-3px); }
.cs-hero h1 { font: 900 var(--step-4)/1.02 var(--display); letter-spacing: -0.02em; max-width: 16ch; }
.cs-hero .lede { font-size: var(--step-1); color: var(--muted); max-width: 48ch; }
.facts { display: flex; flex-wrap: wrap; gap: 10px; list-style: none; padding: 0; margin: 4px 0 0; }
.facts li { font: 500 0.82rem/1 var(--mono); padding: 0.55em 0.8em; border: 1px solid var(--rule); border-radius: 999px; color: var(--muted); }
.cs-body { padding-block: 0 clamp(56px, 8vw, 96px); }
.cs-row { display: grid; gap: 10px 40px; padding-block: 28px; border-top: 1px solid var(--rule); }
.cs-row:last-child { border-bottom: 1px solid var(--rule); }
.cs-row .text { display: grid; gap: 14px; max-width: 62ch; min-width: 0; }
.cs-row ul { margin: 0; padding-left: 1.2em; display: grid; gap: 6px; }
.outcome { font: 700 var(--step-2)/1.25 var(--display); }
@media (min-width: 860px) { .cs-row { grid-template-columns: 14rem minmax(0, 1fr); } }
.next { display: grid; gap: 8px; padding-block: clamp(40px, 6vw, 72px); text-decoration: none; }
.next h2 { font: 700 var(--step-3)/1.08 var(--display); }
.next:hover h2 span { background: linear-gradient(var(--spark), var(--spark)) no-repeat 0 85% / 100% 30%; }

/* Night: the homepage only. Black ground, yellow is the single light source. Case-study pages stay light for reading. */
body.night, .night {
  --paper: #050505;
  --paper-2: #111111;
  --ink: #ecebe6;
  --muted: #9d9c97;
  --rule: #262626;
  color-scheme: dark;
  font-size: 1.125rem;
}
.night .hero { position: relative; overflow: hidden; isolation: isolate; }
.night .hero .wrap { position: relative; z-index: 1; }
.night .hero h1 .quiet { color: color-mix(in srgb, var(--ink) 62%, var(--paper)); }
.night .hero .btn { background: var(--spark); color: var(--on-spark); }
.sparks { position: absolute; inset: 0; width: 100%; height: 100%; z-index: 0; pointer-events: none; }
.night .section-head h2, .night .case h3 { font-weight: 900; }
.night .step h3 { font-weight: 600; }
.night .logo { opacity: 0.72; }
.night .quote { background: var(--paper-2); }
.night .quote blockquote { font-weight: 700; }
.night .stat { border-top-color: var(--spark); }
.night .contact { background: var(--paper); color: var(--ink); border-top: 1px solid var(--rule); }
.night .contact .label { color: var(--muted); }
.night .email { color: var(--spark); font-size: clamp(1.25rem, 0.95rem + 1.5vw, 2rem); }
.night .copy-btn { border-color: var(--rule); }
.night .copy-btn:hover { border-color: var(--spark); color: var(--spark); }
.night .site-footer { border-top: 1px solid var(--rule); }
.night :focus-visible { outline-color: var(--spark); }
.night .site-header { border-bottom-color: transparent; }
.night .clients { border-top-color: transparent; }

/* Case studies in the hybrid: black frame (header, opening, contact), light reading body */
.night:not(body) { font-size: inherit; background: var(--paper); color: var(--ink); }
.site-header.night { border-bottom-color: transparent; background: var(--paper); }
.cs-hero { grid-template-columns: minmax(0, 1fr); align-items: end; }
.cs-intro { display: grid; gap: 22px; min-width: 0; }
.cs-proof { display: grid; gap: 8px; border-top: 2px solid var(--spark); padding-top: 16px; max-width: 22rem; }
.cs-proof .big { font: 900 clamp(2.5rem, 1.4rem + 3.4vw, 4.25rem)/0.95 var(--display); letter-spacing: -0.03em; color: var(--spark); }
.cs-proof p:not(.big) { color: var(--muted); }
.cs-open .facts li { border-color: var(--rule); }
.cs-open + .cs-body { padding-top: clamp(40px, 6vw, 72px); }
@media (min-width: 900px) { .cs-hero { grid-template-columns: minmax(0, 1fr) minmax(0, 20rem); column-gap: 64px; } }

/* Dusk: case-study reading body. Soft dark grey, off-white text, a step down from the black frame. */
body.dusk {
  --paper: #111111;
  --paper-2: #1a1a1a;
  --ink: #e7e6e1;
  --muted: #a3a29d;
  --rule: #2a2a2a;
  color-scheme: dark;
  font-size: 1.125rem;
  line-height: 1.7;
}