:root {
    --brand-blue: #234A91;
  }
  
  /* Banner / header background */
  .banner {
    background-color: var(--brand-blue);
  }
  
  /* Force white text/icons inside the banner only */
  .banner a,
  .banner button span,
  .banner nav a {
    color: #ffffff;
  }
  
  /* assets/css/style.css  (or inside a <style> block) */
.link-underline {
  position: relative;
}
.link-underline::after {
  content:'';
  position:absolute; left:0; bottom:-2px;
  width:100%; height:2px; background:#fbbf24;   /* amber-400 */
  transform:scaleX(0); transform-origin:left;
  transition:transform .25s ease;
}
.link-underline:hover::after,
.link-underline:focus-visible::after {
  transform:scaleX(1);
}