/* === set these to match your header container === */
:root{
  --content-max: 1200px;     /* header/content max width on desktop */
  --content-max-tablet: 960px;/* header/content max width on tablet (if used) */
  --min-gutter: 24px;        /* minimum side space on phones */
  --band-bg: #eef4ff;        /* light blue fill */
  --band-rule: #1e6bb8;      /* blue line color */
}

/* Blue band module */
.hc-band{
  display: block !important;
  float: none !important;
  flex: 0 0 auto !important;         /* don't stretch in flex parents */

  /* Center and size to match the header's content width,
     but never go closer than 24px to the viewport edges */
  width: min(var(--content-max), calc(100vw - (var(--min-gutter) * 2))) !important;
  margin-left: auto !important;
  margin-right: auto !important;
  box-sizing: border-box;

  /* Visuals */
  background: var(--band-bg);
  border-top: 2px solid var(--band-rule);
  border-bottom: 2px solid var(--band-rule);
  padding: 12px 16px;
}

/* Tablet breakpoint: match the header's tablet max width (if your header changes) */
@media (min-width: 768px) and (max-width: 1199px){
  .hc-band{
    width: min(var(--content-max-tablet), calc(100vw - (var(--min-gutter) * 2))) !important;
  }
}
/* === Configure to your header/container widths === */
:root{
  --content-max: 1200px;       /* header/content max width on desktop */
  --content-max-tablet: 960px; /* header/content max width on tablet (if applicable) */
  --min-gutter: 24px;          /* min side space on phones */
}

/* Rich Text modules that should match header width */
.rt-match{
  display: block !important;
  float: none !important;
  flex: 0 0 auto !important;
  box-sizing: border-box;

  /* Center and size to the same width as the header/content area */
  width: min(var(--content-max), calc(100vw - (var(--min-gutter) * 2))) !important;
  margin-left: auto !important;
  margin-right: auto !important;

  /* Optional: tidy defaults */
  padding: 0;                   /* keep the module flush; add inner padding if you want */
}
@media (min-width: 768px) and (max-width: 1199px){
  .rt-match{
    width: min(var(--content-max-tablet), calc(100vw - (var(--min-gutter) * 2))) !important;
  }
}

/* Nice-to-haves inside Rich Text */
.rt-match .hs-richtext{ margin: 0; }
.rt-match img{ max-width: 100%; height: auto; }  /* prevent oversized images */
<style>
/* Remove underlines inside Rich Text modules with class rt-match */
.dnd-section .rt-match .hs-richtext a,
.dnd-section .rt-match .hs-richtext a:link,
.dnd-section .rt-match .hs-richtext a:visited,
.dnd-section .rt-match .hs-richtext a:hover,
.dnd-section .rt-match .hs-richtext a:active,
.dnd-section .rt-match .hs-richtext a:focus,
.dnd-section .rt-match .hs-richtext a * {
  text-decoration: none !important;
  -webkit-text-decoration: none !important;
  border-bottom: 0 !important;            /* themes that fake underlines */
  box-shadow: none !important;            /* hover underline effects */
  background-image: none !important;      /* gradient underlines */
}

/* Kill pseudo-element based underlines */
.dnd-section .rt-match .hs-richtext a::before,
.dnd-section .rt-match .hs-richtext a::after {
  content: none !important;
}

/* If the editor inserted <u> tags or inline text-decoration */
.dnd-section .rt-match .hs-richtext u,
.dnd-section .rt-match .hs-richtext [style*="text-decoration"] {
  text-decoration: none !important;
  border: 0 !important;
  box-shadow: none !important;
  background-image: none !important;
}
</style>