/* ===========================================================
   Mercer Lindsay Lab — Stylesheet
   Palette: Desert Landscape (schemecolor.com) w/ WCM Red swap
   Typography: Fraunces (display) + General Sans (body)
=========================================================== */

/* ---------- Base reset ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html {
  -moz-text-size-adjust: none;
  -webkit-text-size-adjust: none;
  text-size-adjust: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
  hanging-punctuation: first last;
  scroll-padding-top: 5.5rem;
}

body {
  min-height: 100dvh;
  line-height: 1.65;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background-color: var(--color-bg);
}

img, picture, video, canvas, svg { display: block; max-width: 100%; height: auto; }
ul[role="list"], ol[role="list"] { list-style: none; }
input, button, textarea, select { font: inherit; color: inherit; }

h1, h2, h3, h4, h5, h6 { text-wrap: balance; line-height: 1.15; font-family: var(--font-display); font-weight: 600; }
p, li, figcaption { text-wrap: pretty; }

a { color: inherit; text-decoration: none; }

::selection { background: color-mix(in oklab, var(--color-primary) 30%, transparent); color: var(--color-text); }

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

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

button { cursor: pointer; background: none; border: none; }
table { border-collapse: collapse; width: 100%; }

a, button, [role="button"] {
  transition: color 180ms cubic-bezier(0.16,1,0.3,1),
              background 180ms cubic-bezier(0.16,1,0.3,1),
              border-color 180ms cubic-bezier(0.16,1,0.3,1),
              box-shadow 180ms cubic-bezier(0.16,1,0.3,1),
              transform 180ms cubic-bezier(0.16,1,0.3,1);
}

.sr-only {
  position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px;
  overflow: hidden; clip: rect(0,0,0,0); white-space: nowrap; border-width: 0;
}

/* ---------- Design Tokens ---------- */
:root {
  /* Type scale */
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.25rem);
  --text-3xl: clamp(2.4rem, 1rem + 4vw, 4.5rem);
  --text-hero: clamp(2.8rem, 0.7rem + 6vw, 6rem);

  /* Spacing (4px system) */
  --space-1: 0.25rem; --space-2: 0.5rem; --space-3: 0.75rem; --space-4: 1rem;
  --space-5: 1.25rem; --space-6: 1.5rem; --space-8: 2rem; --space-10: 2.5rem;
  --space-12: 3rem; --space-16: 4rem; --space-20: 5rem; --space-24: 6rem; --space-32: 8rem;

  --radius-sm: 0.375rem; --radius-md: 0.6rem; --radius-lg: 0.9rem; --radius-xl: 1.4rem; --radius-full: 9999px;

  --content-narrow: 640px;
  --content-default: 780px;
  --content-wide: 1180px;
  --content-full: 100%;

  --font-display: 'Fraunces', 'Iowan Old Style', Georgia, serif;
  --font-body: 'General Sans', 'Helvetica Neue', Arial, sans-serif;

  /* ---- Desert Landscape palette (light) ---- */
  --clr-black: #030102;
  --clr-red: #B31B1B;        /* Weill Cornell red (replaces Aesthetic Maroon) */
  --clr-red-bright: #EB3327; /* Laser Red */
  --clr-gold: #EA9F28;       /* Fire Bush */
  --clr-yellow: #FFD863;     /* Juliana */
  --clr-purple: #3E2C46;     /* Matte Purple */

  --color-bg: #FBF7F0;
  --color-surface: #FFFFFF;
  --color-surface-2: #F6EFE2;
  --color-surface-offset: #F0E6D3;
  --color-surface-dynamic: #E9DCC0;
  --color-divider: #E3D5B8;
  --color-border: #D7C6A0;

  --color-text: var(--clr-black);
  --color-text-muted: #5E564A;
  --color-text-faint: #A0937A;
  --color-text-inverse: #FBF7F0;

  --color-primary: var(--clr-red);
  --color-primary-hover: #8F1515;
  --color-primary-active: #6B1010;
  --color-primary-highlight: #F3D9D3;

  --color-gold: var(--clr-gold);
  --color-gold-highlight: #FBEACB;
  --color-purple: var(--clr-purple);
  --color-purple-highlight: #E3DAE6;

  --shadow-sm: 0 1px 2px rgba(3,1,2,0.06);
  --shadow-md: 0 8px 24px rgba(3,1,2,0.08);
  --shadow-lg: 0 20px 48px rgba(3,1,2,0.14);
}

[data-theme='dark'] {
  --color-bg: #0B0908;
  --color-surface: #151210;
  --color-surface-2: #1B1815;
  --color-surface-offset: #211D18;
  --color-surface-dynamic: #2A251E;
  --color-divider: #2E2822;
  --color-border: #40382D;

  --color-text: #F2EADB;
  --color-text-muted: #B7AC98;
  --color-text-faint: #7C7261;
  --color-text-inverse: #151210;

  --color-primary: #E4483C;
  --color-primary-hover: #EB3327;
  --color-primary-active: #F4685D;
  --color-primary-highlight: #3C1E1A;

  --color-gold: #EFAE45;
  --color-gold-highlight: #3A2E17;
  --color-purple: #8F72A0;
  --color-purple-highlight: #2A2130;

  --shadow-sm: 0 1px 2px rgba(0,0,0,0.3);
  --shadow-md: 0 8px 24px rgba(0,0,0,0.35);
  --shadow-lg: 0 24px 56px rgba(0,0,0,0.5);
}

/* ---------- Layout helpers ---------- */
.wrap {
  width: 100%;
  max-width: var(--content-wide);
  margin-inline: auto;
  padding-inline: clamp(var(--space-5), 4vw, var(--space-10));
}
.wrap--narrow { max-width: var(--content-default); }

.section { padding-block: clamp(var(--space-16), 8vw, var(--space-32)); }
.section--tight { padding-block: clamp(var(--space-10), 6vw, var(--space-20)); }
.section--surface { background: var(--color-surface); }
.section--offset { background: var(--color-surface-offset); }

.eyebrow {
  display: inline-flex; align-items: center; gap: var(--space-2);
  font-size: var(--text-xs); letter-spacing: 0.14em; text-transform: uppercase;
  font-weight: 600; color: var(--color-primary);
}
.eyebrow::before {
  content: ""; width: 22px; height: 2px; background: var(--color-primary); display: inline-block;
}

h1 { font-size: var(--text-hero); font-weight: 500; letter-spacing: -0.01em; }
h2.section-title { font-size: var(--text-2xl); font-weight: 500; letter-spacing: -0.01em; margin-top: var(--space-3); }
h3.card-title { font-size: var(--text-lg); font-weight: 600; font-family: var(--font-body); }

.lede { font-size: var(--text-lg); color: var(--color-text-muted); line-height: 1.55; font-family: var(--font-body); font-weight: 400; }

p.body-text, .prose p { max-width: 68ch; }
.prose p + p, .prose ul + p, .prose p + ul { margin-top: var(--space-5); }
.prose h3 { font-size: var(--text-lg); margin-top: var(--space-10); margin-bottom: var(--space-3); }
.prose ul { padding-left: var(--space-6); margin-top: var(--space-3); }
.prose li { list-style: disc; margin-bottom: var(--space-2); max-width: 66ch; }
.prose em { font-style: italic; color: var(--color-text); }

/* ---------- Header / Nav ---------- */
.site-header {
  position: sticky; top: 0; z-index: 50;
  background: color-mix(in oklab, var(--color-bg) 88%, transparent);
  backdrop-filter: blur(14px);
  border-bottom: 1px solid var(--color-divider);
}
.nav {
  display: flex; align-items: center; justify-content: space-between;
  padding-block: var(--space-4);
}
.brand { display: flex; align-items: center; gap: var(--space-3); }
.brand-mark { width: 34px; height: 34px; flex-shrink: 0; border-radius: 50%; object-fit: cover; object-position: center; border: 1px solid var(--color-border); }
.brand-mark-dark { display: none; }
[data-theme="dark"] .brand-mark-light { display: none; }
[data-theme="dark"] .brand-mark-dark { display: block; }
.brand-text { display: flex; flex-direction: column; line-height: 1.15; }
.brand-name { font-family: var(--font-display); font-weight: 600; font-size: var(--text-base); }
.brand-sub { font-size: 0.68rem; letter-spacing: 0.08em; text-transform: uppercase; color: var(--color-text-muted); }

.nav-links {
  display: flex; align-items: center; gap: var(--space-8);
  font-size: var(--text-sm); font-weight: 500;
}
.nav-links a { position: relative; padding-block: var(--space-1); color: var(--color-text-muted); }
.nav-links a:hover, .nav-links a[aria-current="page"] { color: var(--color-text); }
.nav-links a[aria-current="page"]::after {
  content: ""; position: absolute; left: 0; right: 0; bottom: -4px; height: 2px; background: var(--color-primary);
}

.nav-right { display: flex; align-items: center; gap: var(--space-4); }

.theme-toggle {
  display: inline-flex; align-items: center; justify-content: center;
  width: 36px; height: 36px; border-radius: var(--radius-full);
  border: 1px solid var(--color-border); color: var(--color-text);
}
.theme-toggle:hover { background: var(--color-surface-offset); }

.nav-toggle {
  display: none; width: 40px; height: 40px; align-items: center; justify-content: center;
  border-radius: var(--radius-md); border: 1px solid var(--color-border);
}

.btn {
  display: inline-flex; align-items: center; justify-content: center; gap: var(--space-2);
  padding: var(--space-3) var(--space-6); border-radius: var(--radius-full);
  font-size: var(--text-sm); font-weight: 600; white-space: nowrap;
}
.btn--primary { background: var(--color-primary); color: #fff; }
.btn--primary:hover { background: var(--color-primary-hover); transform: translateY(-1px); box-shadow: var(--shadow-md); }
.btn--ghost { border: 1px solid var(--color-border); color: var(--color-text); }
.btn--ghost:hover { border-color: var(--color-primary); color: var(--color-primary); }

/* ---------- Hero ---------- */
.hero {
  position: relative; overflow: hidden; color: #F2EADB;
  min-height: 84vh; display: flex; align-items: center;
}
.hero::before {
  content: ""; position: absolute; inset: 0; background: linear-gradient(180deg, rgba(3,1,2,0.55) 0%, rgba(3,1,2,0.78) 55%, rgba(3,1,2,0.94) 100%), var(--hero-img); background-size: cover; background-position: center 30%;
  z-index: 0;
}
.hero-inner { position: relative; z-index: 1; padding-block: var(--space-32) var(--space-20); }
.hero .eyebrow { color: var(--clr-yellow); }
.hero .eyebrow::before { background: var(--clr-yellow); }
.hero h1 { color: #FBF7F0; max-width: 26ch; margin-top: var(--space-4); font-size: clamp(2.2rem, 0.6rem + 4.4vw, 4.5rem); }
.hero-sub { max-width: 56ch; font-size: var(--text-lg); color: #E7DFCF; margin-top: var(--space-6); font-family: var(--font-body); font-weight: 400; }
.hero-cta { display: flex; gap: var(--space-4); margin-top: var(--space-10); flex-wrap: wrap; }
.hero .btn--ghost { border-color: rgba(242,234,219,0.4); color: #F2EADB; }
.hero .btn--ghost:hover { border-color: var(--clr-yellow); color: var(--clr-yellow); }

.page-hero {
  padding-block: clamp(var(--space-24), 12vw, var(--space-32)) var(--space-16);
  background: linear-gradient(180deg, var(--color-surface-offset), var(--color-bg));
  border-bottom: 1px solid var(--color-divider);
}
.page-hero h1 { font-size: var(--text-2xl); max-width: 22ch; }
.page-hero .lede { margin-top: var(--space-5); max-width: 62ch; }

/* ---------- Cards & grids ---------- */
.grid { display: grid; gap: var(--space-8); }
.grid--4 { grid-template-columns: repeat(4, 1fr); }
.grid--3 { grid-template-columns: repeat(3, 1fr); }
.grid--2 { grid-template-columns: repeat(2, 1fr); }
@media (max-width: 980px) { .grid--4 { grid-template-columns: repeat(2, 1fr); } .grid--3 { grid-template-columns: repeat(2,1fr); } }
@media (max-width: 640px) { .grid--4, .grid--3, .grid--2 { grid-template-columns: 1fr; } }

.card {
  background: var(--color-surface); border: 1px solid var(--color-divider);
  border-radius: var(--radius-lg); padding: var(--space-8);
  transition: border-color 200ms ease, transform 200ms ease, box-shadow 200ms ease;
}
.card:hover { border-color: var(--color-primary); transform: translateY(-3px); box-shadow: var(--shadow-md); }
.card-icon {
  width: 44px; height: 44px; border-radius: var(--radius-md);
  background: var(--color-primary-highlight); color: var(--color-primary);
  display: flex; align-items: center; justify-content: center; margin-bottom: var(--space-5);
}
.card p { color: var(--color-text-muted); font-size: var(--text-sm); margin-top: var(--space-3); }

.tag {
  display: inline-flex; padding: var(--space-1) var(--space-3); border-radius: var(--radius-full);
  font-size: var(--text-xs); font-weight: 600; letter-spacing: 0.02em;
  background: var(--color-gold-highlight); color: #7A5310;
}
[data-theme='dark'] .tag { color: var(--clr-yellow); }
.tag--purple { background: var(--color-purple-highlight); color: var(--color-purple); }

/* ---------- Two column / figure blocks ---------- */
.split {
  display: grid; grid-template-columns: 1.05fr 0.95fr; gap: clamp(var(--space-8), 6vw, var(--space-20));
  align-items: center;
}
.split--reverse .split-media { order: 2; }
@media (max-width: 900px) { .split { grid-template-columns: 1fr; } .split--reverse .split-media { order: 0; } }

.figure { border-radius: var(--radius-lg); overflow: hidden; border: 1px solid var(--color-divider); background: var(--color-surface-2); }
.figure img { width: 100%; }
.figure figcaption {
  padding: var(--space-5) var(--space-6); font-size: var(--text-xs); color: var(--color-text-muted); line-height: 1.6;
  border-top: 1px solid var(--color-divider);
}
.figure figcaption strong { color: var(--color-text); }

.pull-quote {
  font-family: var(--font-display); font-size: var(--text-lg); font-style: italic; font-weight: 400;
  color: var(--color-text); border-left: 3px solid var(--color-primary); padding-left: var(--space-6);
  margin-block: var(--space-10); max-width: 60ch;
}

/* ---------- Project cards (research directions) ---------- */
.project {
  display: grid; grid-template-columns: 220px 1fr; gap: var(--space-8);
  padding-block: var(--space-10); border-top: 1px solid var(--color-divider);
}
.project:first-of-type { border-top: none; }
@media (max-width: 760px) { .project { grid-template-columns: 1fr; gap: var(--space-3); } }
.project-label { display: flex; flex-direction: column; gap: var(--space-3); }
.project-num { font-family: var(--font-display); font-size: var(--text-xl); color: var(--color-primary); font-weight: 500; }
.project h3 { font-size: var(--text-lg); margin-bottom: var(--space-3); font-family: var(--font-body); font-weight: 600; }
.project p { color: var(--color-text-muted); max-width: 68ch; }

/* ---------- Timeline (People page) ---------- */
.timeline { position: relative; padding-left: var(--space-8); }
.timeline::before { content: ""; position: absolute; left: 5px; top: 6px; bottom: 6px; width: 2px; background: var(--color-divider); }
.timeline-item { position: relative; padding-bottom: var(--space-10); }
.timeline-item:last-child { padding-bottom: 0; }
.timeline-item::before {
  content: ""; position: absolute; left: -35px; top: 4px; width: 12px; height: 12px; border-radius: 50%;
  background: var(--color-primary); border: 3px solid var(--color-bg);
}
.timeline-year { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.08em; color: var(--color-primary); font-weight: 700; }
.timeline-item h4 { font-size: var(--text-base); font-family: var(--font-body); font-weight: 600; margin-top: var(--space-1); }
.timeline-item p { color: var(--color-text-muted); font-size: var(--text-sm); margin-top: var(--space-2); max-width: 60ch; }

/* ---------- PI profile ---------- */
.pi-card { display: grid; grid-template-columns: 300px 1fr; gap: var(--space-12); align-items: start; }
@media (max-width: 820px) { .pi-card { grid-template-columns: 1fr; } }
.pi-photo { border-radius: var(--radius-xl); overflow: hidden; border: 1px solid var(--color-divider); box-shadow: var(--shadow-md); }
.pi-photo img { aspect-ratio: 9/10; object-fit: cover; }

/* ---------- Publications ---------- */
.pub-list { display: flex; flex-direction: column; }
.pub-item { padding-block: var(--space-6); border-top: 1px solid var(--color-divider); display: flex; gap: var(--space-6); align-items: flex-start; }
.pub-list .pub-item:first-child { border-top: none; }
.pub-year {
  flex-shrink: 0; width: 64px; font-family: var(--font-display); font-size: var(--text-lg); color: var(--color-primary); font-weight: 500;
}
.pub-body p { color: var(--color-text-muted); font-size: var(--text-sm); }
.pub-body .pub-title { color: var(--color-text); font-size: var(--text-base); font-weight: 600; font-family: var(--font-body); margin-bottom: var(--space-1); }
.pub-body .pub-journal { font-style: italic; }
.pub-link { display: inline-flex; align-items: center; gap: var(--space-1); font-size: var(--text-xs); font-weight: 600; color: var(--color-primary); margin-top: var(--space-2); }
.pub-link:hover { text-decoration: underline; }
@media (max-width: 600px) { .pub-item { flex-direction: column; gap: var(--space-2); } .pub-year { width: auto; } }

/* ---------- Approach grid icons ---------- */
.approach-icon { width: 26px; height: 26px; }

/* ---------- CTA band ---------- */
.cta-band {
  background: var(--color-purple); color: #F2EADB; border-radius: var(--radius-xl);
  padding: clamp(var(--space-10), 6vw, var(--space-16));
  display: flex; align-items: center; justify-content: space-between; gap: var(--space-8); flex-wrap: wrap;
}
.cta-band h2 { color: #F9F4E8; font-size: var(--text-xl); font-weight: 500; max-width: 24ch; }
.cta-band p { color: #D9CFE0; margin-top: var(--space-2); max-width: 46ch; }
.cta-band .btn--primary { background: var(--clr-yellow); color: #2A1D08; }
.cta-band .btn--primary:hover { background: #ffe38a; }

/* ---------- Footer ---------- */
.site-footer { background: var(--color-surface-offset); border-top: 1px solid var(--color-divider); padding-block: var(--space-16) var(--space-10); position: relative; overflow: hidden; }
.footer-grid { display: grid; grid-template-columns: 1.4fr 1fr 1fr; gap: var(--space-12); }
@media (max-width: 760px) { .footer-grid { grid-template-columns: 1fr; gap: var(--space-8); } }
.footer-grid h4 { font-size: var(--text-xs); text-transform: uppercase; letter-spacing: 0.1em; color: var(--color-text-muted); margin-bottom: var(--space-4); font-family: var(--font-body); font-weight: 600; }
.footer-links { display: flex; flex-direction: column; gap: var(--space-3); font-size: var(--text-sm); }
.footer-links a:hover { color: var(--color-primary); }
.footer-bottom { display: flex; justify-content: space-between; align-items: center; margin-top: var(--space-16); padding-top: var(--space-8); border-top: 1px solid var(--color-divider); font-size: var(--text-xs); color: var(--color-text-faint); flex-wrap: wrap; gap: var(--space-4); }
.footer-poppy { position: absolute; right: -40px; bottom: -60px; width: 220px; opacity: 0.08; pointer-events: none; }
[data-theme='dark'] .footer-poppy { opacity: 0.12; }

/* ---------- Mobile nav ---------- */
.mobile-menu {
  display: none; position: fixed; inset: 0; z-index: 60; background: var(--color-bg);
  padding: var(--space-6); flex-direction: column; gap: var(--space-6);
}
.mobile-menu.is-open { display: flex; }
.mobile-menu a { font-family: var(--font-display); font-size: var(--text-xl); }
.mobile-menu-close { align-self: flex-end; width: 40px; height: 40px; border: 1px solid var(--color-border); border-radius: var(--radius-md); display: flex; align-items: center; justify-content: center; }

@media (max-width: 860px) {
  .nav-links { display: none; }
  .nav-toggle { display: inline-flex; }
}

/* ---------- Contact page ---------- */
.contact-grid { display: grid; grid-template-columns: 1fr 1fr; gap: var(--space-16); }
@media (max-width: 820px) { .contact-grid { grid-template-columns: 1fr; } }
.contact-item { display: flex; gap: var(--space-4); padding-block: var(--space-5); border-top: 1px solid var(--color-divider); }
.contact-item:first-child { border-top: none; }
.contact-icon { width: 22px; height: 22px; color: var(--color-primary); flex-shrink: 0; margin-top: 2px; }
.contact-item h4 { font-family: var(--font-body); font-size: var(--text-sm); text-transform: uppercase; letter-spacing: 0.06em; color: var(--color-text-muted); margin-bottom: var(--space-1); }
.contact-item p, .contact-item a { font-size: var(--text-base); }
.contact-item a:hover { color: var(--color-primary); }

.map-figure { border-radius: var(--radius-lg); overflow: hidden; border: 1px solid var(--color-divider); }
.map-figure iframe { width: 100%; height: 100%; min-height: 340px; border: 0; display: block; }

/* ---------- Tab panels ---------- */
.tab-panel { display: none; }
.tab-panel.is-active { display: block; animation: tab-fade-in 320ms cubic-bezier(0.16,1,0.3,1); }
@keyframes tab-fade-in { from { opacity: 0; } to { opacity: 1; } }
@media (prefers-reduced-motion: reduce) { .tab-panel.is-active { animation: none; } }

/* ---------- Utility ---------- */
.mt-2{margin-top:var(--space-2)} .mt-4{margin-top:var(--space-4)} .mt-6{margin-top:var(--space-6)} .mt-8{margin-top:var(--space-8)} .mt-10{margin-top:var(--space-10)} .mt-12{margin-top:var(--space-12)} .mt-16{margin-top:var(--space-16)}
.text-center{text-align:center}
.max-w{max-width:var(--content-default); margin-inline:auto}