/* claude1 frontend layout. Brand color lives in --color; u2 derives the rest. */

#container {
  /* Change this one value to re-theme the whole site. */
  --color: #2f6f9e;

  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  background:
    radial-gradient(120% 60% at 100% 0%, var(--color-lightest), transparent 60%),
    var(--color-bg);
  color: var(--color-text);
  font-family: var(--font-1);
  -webkit-font-smoothing: antialiased;
}

/* Header --------------------------------------------------------------- */
#head {
  position: sticky;
  top: 0;
  z-index: 10;
  padding-block: .9rem;
  background: color-mix(in srgb, var(--color-bg), transparent 25%);
  backdrop-filter: blur(14px) saturate(1.4);
  border-bottom: 1px solid color-mix(in srgb, var(--color-line), transparent 88%);
  box-shadow: 0 .4rem 1.2rem color-mix(in srgb, var(--color), transparent 92%);
}
#head .u2-flex { align-items: center; }

#logo {
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: -.03em;
  color: var(--color-dark);
  text-decoration: none;
}
#logo img { display: block; }
#logo::after { /* accent dot for a bit of character */
  content: ".";
  color: var(--accent);
}
#logo:has(img)::after { content: none; }

/* Burger (mobile only, toggles #nav via the hidden checkbox) ------------ */
#burger {
  display: none;
  cursor: pointer;
  color: var(--color-dark);
}
#burger .-close { display: none; }
#navtoggle:checked ~ #burger .-menu { display: none; }
#navtoggle:checked ~ #burger .-close { display: inline; }

/* Nav (cms.cont.nav3 markup) ------------------------------------------- */
#nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: .15rem;
  margin: 0;
  padding: 0;
  list-style: none;
}
#nav ul ul { display: none; } /* keep the header to a single row */

#nav a {
  display: block;
  padding: .45rem .9rem;
  border-radius: 2rem;
  font-weight: 500;
  color: var(--color-text);
  text-decoration: none;
  transition: background .18s, color .18s;
}
#nav a:hover { background: color-mix(in srgb, var(--accent), transparent 90%); }
#nav :is(.cmsActive, .cmsInside) > a {
  background: var(--accent);
  color: var(--accent-lightest);
  box-shadow: 0 .3rem .8rem color-mix(in srgb, var(--accent), transparent 65%);
}

/* Main ----------------------------------------------------------------- */
#content {
  flex: 1;
  padding-block: clamp(2.5rem, 6vw, 5rem);
}

/* Footer --------------------------------------------------------------- */
#foot {
  margin-top: 5rem;
  padding-block: 3rem;
  /* brand-tinted dark, not flat black */
  background: linear-gradient(var(--color-darker), var(--color-darkest));
  border-top: 3px solid var(--accent);
  color: color-mix(in srgb, var(--color-lightest), transparent 20%);
  line-height: 1.7;
}
#foot a {
  color: var(--color-lighter);
  text-underline-offset: .2em;
}
#foot a:hover { color: #fff; }

/* Mobile: collapse nav into a burger dropdown --------------------------- */
@media (max-width: 720px) {
  #burger { display: inline-flex; }

  #nav {
    display: none;
    position: absolute;
    inset: 100% 0 auto 0;
    padding: .75rem 1rem 1.25rem;
    background: var(--color-bg);
    border-bottom: 1px solid var(--color-area);
    box-shadow: var(--shadow);
  }
  #navtoggle:checked ~ #nav { display: block; }

  #nav ul { flex-direction: column; gap: .15rem; }
  #nav ul ul { display: block; padding-left: 1rem; } /* show sub-levels in the drawer */
  #nav a { border-radius: var(--radius); }
}