/* ====== SIGMA Lab — Base Styles ====== */
:root{
  --theme: #d2e1de;        /* requested theme color */
  --ink: #0f172a;          /* near-black (good contrast on theme/bg) */
  --ink-muted: #475569;    /* slate */
  --header: #56a39d;       /* header)= */
  --accent: #0f766e;       /* teal for links/buttons (AA contrast on theme) */
  --card-bg: #ffffff;
  --card-border: #e2e8f0;
  --shadow: 0 10px 30px rgba(2,6,23,.07);
  --radius: 14px;
  --container: 1200px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0;
  font-family: ui-sans-serif, system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, "Noto Sans", "Liberation Sans", sans-serif;
  color: var(--ink);
  background-color: #f8fafc; /* subtle gray backdrop */
  line-height: 1.6;
}

/* Layout */
.container { max-width: var(--container); margin-inline: auto; padding-inline: 1rem; }

/* Skip link for accessibility */
.skip-link {
  position: absolute; left: -999px; padding: .5rem .75rem; background: #fff; color: var(--ink);
  border-radius: 8px; box-shadow: var(--shadow);
}
.skip-link:focus { left: 1rem; top: 1rem; z-index: 1000; }


.lab-logo {
  height: 80px;           /* Adjust to fit nicely in your header */
  width: auto;            /* Keeps proportions */
  margin-right: 0.75rem;  /* Adds space before the lab name */
  vertical-align: middle; /* Aligns with text */
}

/* Header / Nav */

a {
  color: var(--accent);
  text-decoration: none;
}

a:hover {
  color: #0d9488; /* a slightly lighter teal for hover */
  text-decoration: underline;
}

.site-header {
  background: var(--theme);
  border-bottom: 1px solid rgba(15,23,42,.1);
}
.nav {
  display: flex; align-items: center; justify-content: space-between; gap: 1rem; padding: 1rem 0;
}
.brand { display: flex; align-items: center; gap: .75rem; text-decoration: none; color: var(--ink); }
.brand .logo {
  width: 40px; height: 40px; display: inline-block; background: #0b3d3a10; border-radius: 10px;
}
.brand .name { font-weight: 800; letter-spacing: .2px; font-size: 1.25rem; }
.primary-nav a {
  text-decoration: none; color: var(--ink); padding: .5rem .25rem; margin: 0 .25rem;
  border-bottom: 2px solid transparent;
}
.primary-nav a:hover { border-bottom-color: var(--accent); }
.primary-nav a.current { border-bottom-color: var(--accent); color: var(--accent); }

/* Hero */
.hero {
  background: var(--theme);
  padding: 4rem 0 3rem;
}
.hero h1 { margin: 0 0 .5rem; font-size: clamp(2rem, 2.6vw + 1rem, 3rem); }
.hero p  { color: var(--ink-muted); max-width: 58ch; }

/* Sections */
.section { padding: 2.5rem 0; }
.section-header {
  display: flex; align-items: baseline; justify-content: space-between; gap: 1rem;
  border-bottom: 2px solid #dbe4ea; padding-bottom: .5rem; margin-bottom: 1.5rem;
}
.section h2 { margin: 0; font-size: 1.6rem; }

/* Cards & grids */
.grid { display: grid; gap: 1rem; }
.grid-2 { grid-template-columns: repeat(auto-fit, minmax(320px, 1fr)); }
.grid-3 { grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
.card {
  background: var(--card-bg); border: 1px solid var(--card-border); border-radius: var(--radius); box-shadow: var(--shadow);
  padding: 1rem 1.1rem;
}
.card h3 { margin-top: 0; margin-bottom: .25rem; }
.meta { color: var(--ink-muted); font-size: .95rem; }

/* Buttons / links */
.btn {
  display: inline-block; padding: .6rem .9rem; border-radius: 999px; text-decoration: none; font-weight: 600;
  background: var(--accent); color: white; box-shadow: var(--shadow);
}
.btn:hover { filter: brightness(0.95); }

/* Footer */
.site-footer {
  background: var(--theme); border-top: 1px solid rgba(15,23,42,.1); padding: 1.2rem 0; color: var(--ink-muted);
}

/* People cards */
.person {
  display: grid; grid-template-columns: 76px 1fr; gap: .9rem; align-items: center;
}
.person img { width: 76px; height: 76px; object-fit: cover; border-radius: 50%; border: 3px solid #ffffff; box-shadow: var(--shadow); }
.person .role { color: var(--ink-muted); margin: 0; }

/* Project tags */
.tags { display: flex; gap: .4rem; flex-wrap: wrap; margin-top: .25rem; }
.tag {
  border: 1px solid #cbd5e1; border-radius: 999px; padding: .18rem .55rem; font-size: .85rem; color: #0f172a;
  background: #ffffffaa;
}

/* Responsive adjustments */
@media (max-width: 640px) {
  .primary-nav { font-size: .95rem; }
}



/* ====== PEOPLE SECTION WITH BACKGROUND IMAGE ====== */
.section-people {
  position: relative;
  background-image: url("../images/background.png"); /* ✅ correct syntax */
  background-size: cover;
  background-position: center;
  background-attachment: fixed; /* optional for parallax feel */
  color: var(--ink);
  padding: 6rem 0;
}

/* subtle overlay for readability */
.section-people::before {
  content: "";
  position: absolute;
  inset: 0;
  background: rgba(210, 225, 222, 0.2); /* soft overlay matching theme */
  backdrop-filter: blur(2px);
}

/* text box */
.overlay-box {
  position: relative;
  z-index: 1;
  background: rgba(255, 255, 255, 0.95);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  max-width: 800px;
  margin: 0 auto;
  padding: 2rem 2.5rem;
  text-align: left;
}

.overlay-box h2 {
  font-size: clamp(2rem, 2.4vw + 0.5rem, 2.8rem); /* scales but stays large */
  font-weight: 800;
  color: var(--ink);
  line-height: 1.2;
  margin-bottom: 0.75rem;
}

.overlay-box p {
  color: var(--ink-muted);
  font-size: 1.1rem;
  line-height: 1.7;
}


/* Highlight SIGNAL initials */
.sig {
  color: var(--accent);                   /* optional: teal letter color */
  font-weight: 700;
  text-decoration: none;                  /* remove default underline */
}