/* ============================================================
   BASE — design tokens + shared layout (header, nav, footer)
   Loaded on every page, before the page-specific stylesheet.
   ============================================================ */

:root{
  /* Color: deep-lab navy, with the magenta/cyan pulled straight
     from the mounted-crystal photos in the group's own lab. */
  --ink:        #0b1220;
  --ink-rgb:    11, 18, 32;      /* NEW — lets rgba() reuse --ink with transparency */
  --panel:      #101a2e;
  --surface-2:  #12294a;         /* NEW — third gradient stop, was hardcoded before */
  --panel-line: #24314c;
  --paper:      #edf1f7;
  --muted:      #93a0b8;
  --accent:     #e63e76;
  --accent-rgb: 230, 62, 118;    /* NEW — lets rgba() reuse --accent with transparency */
  --accent-2:   #4fd8e0;
  --accent-soft: rgba(var(--accent-rgb), 0.14);   /* now derived, not a separate copy */

  /* Type */
  --font-display: "Space Grotesk", "Segoe UI", Arial, sans-serif;
  --font-body:    "IBM Plex Sans", "Segoe UI", Arial, sans-serif;
  --font-mono:    "IBM Plex Mono", "Courier New", monospace;

  --max-width: 1180px;
}

*, *::before, *::after{ box-sizing: border-box; }
html{ scroll-behavior: smooth; }
body{
  margin: 0;
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-size: 16px;
  line-height: 1.65;
}
img{ max-width: 100%; display: block; }
a{ color: inherit; }
h1, h2, h3{
  font-family: var(--font-display);
  font-weight: 600;
  letter-spacing: -0.01em;
  line-height: 1.15;
}
p{ margin: 0 0 1rem; }

/* ---------- header / nav (shared across every page) ---------- */

.site-header{
  background-image: linear-gradient(180deg,rgba(var(--ink-rgb), 0.55) 0%, rgba(var(--ink-rgb), 0.75) 100%),
                     url("../images/bckgnd_header.png");
  background-size: cover;
  background-position: center;
  border-bottom: 1px solid var(--panel-line);
}
.site-header__inner{
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 1.6rem 5vw;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
  flex-wrap: wrap;
}
.brand{
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.05rem;
  letter-spacing: 0.01em;
  text-decoration: none;
  white-space: nowrap;
}
.brand em{
  font-style: normal;
  color: var(--accent);
}
nav ul{
  list-style: none;
  display: flex;
  flex-wrap: wrap;
  gap: 0.25rem;
  margin: 0;
  padding: 0;
}
nav a{
  display: inline-block;
  text-decoration: none;
  color: var(--paper);
  font-family: var(--font-mono);
  font-size: 0.74rem;
  letter-spacing: 0.09em;
  text-transform: uppercase;
  padding: 0.55rem 1rem;
  border-radius: 999px;
  transition: background-color 0.2s ease, color 0.2s ease;
}
nav a:hover,
nav a:focus-visible{
  background-color: var(--accent-soft);
  color: var(--accent);
  outline: none;
}
nav a[aria-current="page"]{
  color: var(--accent-2);
}

/* small reusable signature: a two-tone gradient rule,
   standing in for the beam line running through the lab photos */
.rule{
  height: 2px;
  width: 56px;
  border: 0;
  margin: 1.1rem 0 1.6rem;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

main{
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3.5rem 5vw 5rem;
}

/* ---------- footer (shared) ---------- */

.site-footer{
  border-top: 1px solid var(--panel-line);
  padding: 1.75rem 5vw;
  text-align: center;
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.03em;
  color: var(--muted);
}

/* ---------- focus visibility (accessibility floor) ---------- */
a:focus-visible, button:focus-visible{
  outline: 2px solid var(--accent-2);
  outline-offset: 2px;
}