/* ==========================================================================
   SIGINTENT — minimalist advisory site
   ========================================================================== */

:root {
  --bg:        #ededeb;
  --bg-rgb:    237, 237, 235;
  --surface:   #f6f5f3;
  --surface-2: #fbfaf7;
  --ink:       #1a1a1a;
  --ink-2:     #4f4f4d;
  --ink-3:     #84847f;
  --line:      #d8d7d3;
  --line-2:    #c5c4bf;
  --accent:    #2a2a2a;

  --maxw:     1120px;
  --gutter:   clamp(20px, 4vw, 48px);

  --f-serif:  "Fraunces", Georgia, "Times New Roman", serif;
  --f-sans:   "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
}

:root[data-theme="dark"] {
  --bg:        #0f0f0e;
  --bg-rgb:    15, 15, 14;
  --surface:   #1a1a18;
  --surface-2: #201f1d;
  --ink:       #ededeb;
  --ink-2:     #b8b7b2;
  --ink-3:     #84847f;
  --line:      #2a2a28;
  --line-2:    #3a3a37;
  --accent:    #ededeb;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg:        #0f0f0e;
    --bg-rgb:    15, 15, 14;
    --surface:   #1a1a18;
    --surface-2: #201f1d;
    --ink:       #ededeb;
    --ink-2:     #b8b7b2;
    --ink-3:     #84847f;
    --line:      #2a2a28;
    --line-2:    #3a3a37;
    --accent:    #ededeb;
  }
}

/* reset ------------------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html, body { margin: 0; padding: 0; }
img { max-width: 100%; display: block; }
button { font: inherit; cursor: pointer; }
a { color: inherit; text-decoration: none; }

/* base -------------------------------------------------------------------- */
html { scroll-behavior: smooth; }
body {
  font-family: var(--f-sans);
  font-size: 16px;
  line-height: 1.65;
  color: var(--ink-2);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
  text-rendering: optimizeLegibility;
  transition: background 0.25s ease, color 0.25s ease;
}

h1, h2, h3, h4 {
  font-family: var(--f-serif);
  font-weight: 400;
  color: var(--ink);
  letter-spacing: -0.01em;
  margin: 0 0 0.6em 0;
  font-optical-sizing: auto;
}

h1 { font-size: clamp(2.2rem, 5vw, 3.6rem); line-height: 1.08; letter-spacing: -0.02em; }
h2 { font-size: clamp(1.6rem, 3vw, 2.2rem); line-height: 1.15; }
h3 { font-size: 1.15rem; line-height: 1.3; color: var(--ink); }
p  { margin: 0 0 1em 0; }
strong { color: var(--ink); font-weight: 500; }

/* layout ------------------------------------------------------------------ */
.container {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 var(--gutter);
}

section { padding: clamp(64px, 9vw, 120px) 0; }
.section--tight { padding: clamp(40px, 6vw, 72px) 0; }
.divider { border: 0; border-top: 1px solid var(--line); margin: 0; }

.eyebrow {
  display: inline-block;
  font-family: var(--f-sans);
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 1.4em;
}

.lead {
  font-size: clamp(1.05rem, 1.6vw, 1.2rem);
  color: var(--ink-2);
  max-width: 60ch;
  line-height: 1.6;
}

/* header / nav ------------------------------------------------------------ */
.site-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(var(--bg-rgb), 0.88);
  backdrop-filter: saturate(140%) blur(10px);
  -webkit-backdrop-filter: saturate(140%) blur(10px);
  border-bottom: 1px solid var(--line);
}

/* Anchor scrolling — offset for sticky header */
section[id] { scroll-margin-top: 80px; }
.site-header__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}
.brand {
  display: flex;
  flex-direction: column;
  line-height: 1;
}
.brand__mark {
  font-family: var(--f-sans);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.22em;
  color: var(--ink);
}
.brand__name {
  font-family: var(--f-serif);
  font-size: 0.78rem;
  font-style: italic;
  color: var(--ink-3);
  margin-top: 4px;
  letter-spacing: 0.02em;
}

.nav {
  display: flex;
  align-items: center;
  gap: clamp(16px, 2.4vw, 32px);
}
.nav a {
  font-size: 0.92rem;
  color: var(--ink-2);
  transition: color 0.2s ease;
}
.nav a:hover { color: var(--ink); }
.nav a.active { color: var(--ink); }

.lang-toggle {
  background: none;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  padding: 6px 12px;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 0.1em;
  color: var(--ink-2);
  display: flex;
  align-items: center;
  gap: 6px;
  transition: all 0.2s ease;
}
.lang-toggle:hover { color: var(--ink); border-color: var(--ink-3); }
.lang-toggle .sep { color: var(--line-2); }
.lang-toggle [data-lang-opt].active { color: var(--ink); }

.theme-toggle {
  background: none;
  border: 1px solid var(--line-2);
  border-radius: 999px;
  width: 34px;
  height: 30px;
  padding: 0;
  color: var(--ink-2);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  transition: color 0.2s ease, border-color 0.2s ease;
}
.theme-toggle:hover { color: var(--ink); border-color: var(--ink-3); }
.theme-toggle svg { display: block; }
.theme-toggle .icon-sun { display: none; }
.theme-toggle .icon-moon { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: block; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: none; }
@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle .icon-sun { display: block; }
  :root:not([data-theme="light"]) .theme-toggle .icon-moon { display: none; }
}

.menu-toggle {
  display: none;
  background: none;
  border: 0;
  padding: 8px;
  color: var(--ink);
}

/* hero -------------------------------------------------------------------- */
.hero { padding: clamp(80px, 12vw, 160px) 0 clamp(64px, 9vw, 120px); }
.hero h1 { max-width: 18ch; }
.hero .lead { margin-top: 1.4em; }
.hero__cta {
  margin-top: 2.4em;
  display: flex;
  flex-wrap: wrap;
  gap: 18px 28px;
  align-items: center;
}

/* buttons ----------------------------------------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 13px 22px;
  border: 1px solid var(--ink);
  color: var(--ink);
  background: transparent;
  font-size: 0.9rem;
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: all 0.2s ease;
}
.btn:hover { background: var(--ink); color: var(--bg); }
.btn--ghost { border-color: var(--line-2); color: var(--ink-2); }
.btn--ghost:hover { border-color: var(--ink); background: transparent; color: var(--ink); }
.link-arrow {
  font-size: 0.92rem;
  color: var(--ink);
  border-bottom: 1px solid var(--line-2);
  padding-bottom: 2px;
  transition: border-color 0.2s ease;
}
.link-arrow:hover { border-color: var(--ink); }
.link-arrow::after { content: " →"; color: var(--ink-3); }

/* positioning strip ------------------------------------------------------- */
.strip {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.strip__item {
  padding: 36px 28px;
  border-right: 1px solid var(--line);
  font-family: var(--f-serif);
  font-size: 1.05rem;
  color: var(--ink);
  line-height: 1.4;
}
.strip__item:last-child { border-right: 0; }
.strip__item span {
  display: block;
  font-family: var(--f-sans);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  margin-bottom: 10px;
  font-weight: 500;
}

/* services ---------------------------------------------------------------- */
.section-head { margin-bottom: clamp(40px, 6vw, 72px); }
.section-head h2 { max-width: 22ch; }
.section-head .lead { margin-top: 0.6em; }

.services {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.service {
  padding: 40px 36px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--surface);
  transition: background 0.25s ease;
}
.service:hover { background: var(--surface-2); }
.service__num {
  font-family: var(--f-sans);
  font-size: 0.7rem;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  margin-bottom: 14px;
  font-weight: 500;
}
.service h3 { margin-bottom: 14px; }
.service p { font-size: 0.95rem; margin-bottom: 18px; }
.service ul {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.88rem;
  color: var(--ink-2);
}
.service ul li {
  padding: 6px 0 6px 18px;
  position: relative;
  border-top: 1px solid var(--line);
}
.service ul li:first-child { border-top: 0; }
.service ul li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--ink-3);
}

/* why generalist ---------------------------------------------------------- */
.why {
  display: grid;
  grid-template-columns: 1.1fr 1fr;
  gap: clamp(40px, 6vw, 88px);
  align-items: start;
}
.why__lead {
  font-family: var(--f-serif);
  font-size: clamp(1.3rem, 2.2vw, 1.7rem);
  line-height: 1.4;
  color: var(--ink);
  letter-spacing: -0.005em;
}
.why__claims {
  list-style: none;
  padding: 0;
  margin: 0;
  border-top: 1px solid var(--line);
}
.why__claims li {
  padding: 22px 0 22px 32px;
  border-bottom: 1px solid var(--line);
  position: relative;
  font-size: 0.98rem;
  color: var(--ink);
}
.why__claims li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--ink-3);
}

/* approach ---------------------------------------------------------------- */
.approach {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: clamp(28px, 4vw, 56px);
}
.step__num {
  font-family: var(--f-serif);
  font-size: 2.4rem;
  color: var(--ink-3);
  line-height: 1;
  margin-bottom: 18px;
  font-style: italic;
}
.step h3 { margin-bottom: 10px; }
.step p { font-size: 0.95rem; }

/* clients ----------------------------------------------------------------- */
.clients {
  display: flex;
  flex-wrap: wrap;
  gap: 0;
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}
.clients span {
  padding: 22px 28px;
  font-family: var(--f-serif);
  font-size: 1.05rem;
  color: var(--ink);
  border-right: 1px solid var(--line);
  flex: 1 1 auto;
  text-align: center;
  letter-spacing: 0.01em;
}
.clients span:last-child { border-right: 0; }

/* about teaser ------------------------------------------------------------ */
.about-teaser {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: clamp(32px, 5vw, 72px);
  align-items: start;
}
.about-teaser__img {
  position: relative;
  background: var(--line);
  aspect-ratio: 4 / 5;
  overflow: hidden;
}
.about-teaser__img img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  filter: grayscale(100%) contrast(0.95);
}
.about-teaser__body h2 { max-width: 16ch; }
.about-teaser__body .lead { margin-bottom: 1.6em; }

/* writing ----------------------------------------------------------------- */
.writing {
  border-top: 1px solid var(--line);
}
.writing__item {
  display: grid;
  grid-template-columns: 100px 1fr auto;
  gap: 28px;
  align-items: baseline;
  padding: 28px 0;
  border-bottom: 1px solid var(--line);
  transition: padding-left 0.3s ease;
}
.writing__item:hover { padding-left: 12px; }
.writing__date {
  font-size: 0.78rem;
  letter-spacing: 0.1em;
  color: var(--ink-3);
  text-transform: uppercase;
}
.writing__title {
  font-family: var(--f-serif);
  font-size: 1.2rem;
  color: var(--ink);
}
.writing__meta { font-size: 0.82rem; color: var(--ink-3); }

/* closing CTA ------------------------------------------------------------- */
.closing {
  text-align: center;
  padding: clamp(80px, 11vw, 140px) 0;
  border-top: 1px solid var(--line);
}
.closing h2 {
  font-size: clamp(1.8rem, 4vw, 2.8rem);
  max-width: 20ch;
  margin: 0 auto 1em;
}
.closing .btn { margin-top: 12px; }

/* footer ------------------------------------------------------------------ */
.site-footer {
  border-top: 1px solid var(--line);
  padding: 56px 0 40px;
  background: var(--bg);
}
.site-footer__inner {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr;
  gap: 40px;
}
.site-footer h4 {
  font-family: var(--f-sans);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 500;
  margin-bottom: 18px;
}
.site-footer ul { list-style: none; padding: 0; margin: 0; }
.site-footer li { padding: 5px 0; font-size: 0.92rem; }
.site-footer li a { color: var(--ink-2); }
.site-footer li a:hover { color: var(--ink); }
.site-footer__brand .brand__mark { font-size: 1rem; }
.site-footer__brand p {
  font-size: 0.85rem;
  color: var(--ink-3);
  max-width: 32ch;
  margin-top: 12px;
}
.site-footer__legal {
  margin-top: 56px;
  padding-top: 24px;
  border-top: 1px solid var(--line);
  display: flex;
  justify-content: space-between;
  font-size: 0.78rem;
  color: var(--ink-3);
}

/* inner page hero --------------------------------------------------------- */
.page-hero {
  padding: clamp(80px, 11vw, 140px) 0 clamp(48px, 7vw, 88px);
  border-bottom: 1px solid var(--line);
}
.page-hero h1 { max-width: 20ch; }

/* prose (about, services detail) ------------------------------------------ */
.prose {
  max-width: 70ch;
}
.prose p { font-size: 1.02rem; line-height: 1.75; margin-bottom: 1.2em; }
.prose h2 { margin-top: 2em; }
.prose h3 { margin-top: 1.8em; }
.prose ul {
  list-style: none;
  padding: 0;
  margin: 1em 0 1.6em;
}
.prose ul li {
  padding: 8px 0 8px 24px;
  position: relative;
  border-top: 1px solid var(--line);
  font-size: 0.98rem;
}
.prose ul li:last-child { border-bottom: 1px solid var(--line); }
.prose ul li::before {
  content: "—";
  position: absolute;
  left: 0;
  color: var(--ink-3);
}

/* two-col layout ---------------------------------------------------------- */
.two-col {
  display: grid;
  grid-template-columns: 1fr 2fr;
  gap: clamp(32px, 5vw, 80px);
  align-items: start;
}
.two-col__aside {
  position: sticky;
  top: 100px;
}
.two-col__aside h3 {
  font-family: var(--f-sans);
  font-size: 0.72rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  color: var(--ink-3);
  font-weight: 500;
  margin-bottom: 14px;
}
.two-col__aside img {
  filter: grayscale(100%) contrast(0.95);
  margin-bottom: 18px;
}

/* contact ----------------------------------------------------------------- */
.contact-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 0;
  border-top: 1px solid var(--line);
  border-left: 1px solid var(--line);
}
.contact-grid > div {
  padding: 36px;
  border-right: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
  background: var(--surface);
}
.contact-grid h3 { font-family: var(--f-sans); font-size: 0.72rem; letter-spacing: 0.16em; text-transform: uppercase; color: var(--ink-3); font-weight: 500; }
.contact-grid p { font-family: var(--f-serif); font-size: 1.2rem; color: var(--ink); }

/* responsive -------------------------------------------------------------- */
@media (max-width: 860px) {
  .menu-toggle { display: block; }
  .nav {
    position: fixed;
    inset: 72px 0 auto 0;
    flex-direction: column;
    align-items: flex-start;
    gap: 0;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    padding: 24px var(--gutter);
    transform: translateY(-120%);
    transition: transform 0.3s ease;
  }
  .nav.is-open { transform: translateY(0); }
  .nav a { padding: 10px 0; width: 100%; border-bottom: 1px solid var(--line); }
  .nav .lang-toggle { margin-top: 14px; }

  .strip { grid-template-columns: 1fr; }
  .strip__item { border-right: 0; border-bottom: 1px solid var(--line); }
  .strip__item:last-child { border-bottom: 0; }

  .services { grid-template-columns: 1fr; }
  .approach { grid-template-columns: 1fr; gap: 32px; }
  .why { grid-template-columns: 1fr; gap: 32px; }
  .about-teaser { grid-template-columns: 1fr; }
  .about-teaser__img { max-width: 320px; }
  .two-col { grid-template-columns: 1fr; }
  .two-col__aside { position: static; }
  .two-col__aside img { max-width: 280px; }
  .contact-grid { grid-template-columns: 1fr; }
  .site-footer__inner { grid-template-columns: 1fr; gap: 32px; }
  .site-footer__legal { flex-direction: column; gap: 8px; }
  .writing__item { grid-template-columns: 1fr; gap: 6px; }
  .clients span { flex: 1 1 50%; border-bottom: 1px solid var(--line); }
}