/*
 * sd-mega — Mega Menu panels of the primary navigation (Session 3.1; Blueprint 5.33, 15.13)
 * Requires: header.css (trigger .sd-nav__trigger, drawer), base.css (sd-link-arrow).
 * Areas: Services, Products, Knowledge Hub. Solutions is a single page and stays a plain link
 * (Navigation_Structure.md 3).
 *
 * One calm pattern for every panel (owner review, Session 3.1: the first version was too busy):
 * ≥ 1280px: vertical dropdown with an introduction (owner choice F-09 A, Session 5.2; replaces the full-width
 *            horizontal panel of D-028): a panel directly below the header bar, aligned with its menu item
 *            (left edge 24 px before the trigger, set by components.js as --sd-mega-left, never past the
 *            header edge). Left: title, one line, and the overview link on a light gray strip. Right: the
 *            pages as one vertical list, one per row; a panel with two groups (Products) shows them as two
 *            short columns. No descriptions, no feature boxes.
 *            Opens on click / Enter / Space (not on hover), one panel at a time.
 * Status notes: "Coming Soon" in copper (sd-mega__link-note--soon, owner request F-09); other notes muted.
 * < 1280px:  the same markup becomes an accordion section in the drawer — overview link first, then titles;
 *            intro text, index numbers and arrows are left out (Blueprint 15.12).
 * Without JS the panels stay closed; every target page is also reachable from the footer and the overview pages.
 */

.sd-mega { display: none; }

.sd-nav__trigger[aria-expanded="true"] + .sd-mega { display: block; }

.sd-mega__list {
  display: grid;
  margin: 0;
  padding: 0;
  list-style: none;
}

.sd-mega__link {
  display: flex;
  align-items: center;
  gap: var(--sd-space-3);
  color: var(--sd-color-text-default);
  text-decoration: none;
}

.sd-mega__link-body { display: grid; flex: 1; min-width: 0; }

.sd-mega__link-title {
  color: var(--sd-color-brand-blue);
  font-size: var(--sd-font-size-ui);
  font-weight: var(--sd-font-weight-medium);
  line-height: var(--sd-line-height-ui);
}

/* Short status note under a title: "Coming Soon", "Flagship service" */
.sd-mega__link-note {
  color: var(--sd-color-text-muted);
  font-size: var(--sd-font-size-label);
  line-height: var(--sd-line-height-label);
}

.sd-mega__link[aria-current="page"] .sd-mega__link-title {
  text-decoration: underline;
  text-decoration-color: var(--sd-color-accent-copper);
  text-decoration-thickness: 2px;
  text-underline-offset: 0.3em;
}

.sd-mega__group-title {
  margin: 0 0 var(--sd-space-2);
  color: var(--sd-color-text-muted);
  font-size: var(--sd-font-size-label);
  font-weight: var(--sd-font-weight-medium);
  line-height: var(--sd-line-height-label);
  letter-spacing: var(--sd-letter-spacing-label);
  text-transform: uppercase;
}

/* ---------- Desktop panel (≥ 1280px) ---------- */

@media (min-width: 1280px) {
  .sd-mega {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--sd-color-surface);
    border-top: var(--sd-border-width) solid var(--sd-color-border-subtle);
    border-bottom: var(--sd-border-width) solid var(--sd-color-border-subtle);
    box-shadow: var(--sd-shadow-overlay);
    animation: sd-mega-in var(--sd-duration-base) var(--sd-ease-out);
  }

  .sd-mega__inner {
    display: grid;
    grid-template-columns: repeat(12, minmax(0, 1fr));
    column-gap: var(--sd-grid-gutter);
    padding-block: var(--sd-space-6);
  }

  .sd-mega__intro {
    grid-column: span 3;
    display: grid;
    align-content: start;
    gap: var(--sd-space-2);
    padding-right: var(--sd-space-5);
  }

  .sd-mega__title {
    margin: 0;
    color: var(--sd-color-text-heading);
    font-size: var(--sd-font-size-h4);
    font-weight: var(--sd-font-weight-medium);
    line-height: var(--sd-line-height-h4);
    letter-spacing: var(--sd-letter-spacing-heading);
  }

  .sd-mega__text {
    margin: 0;
    color: var(--sd-color-text-muted);
    font-size: var(--sd-font-size-small);
    line-height: var(--sd-line-height-small);
  }

  .sd-mega__overview { margin-top: var(--sd-space-2); }

  .sd-mega__body {
    grid-column: span 9;
    display: grid;
    gap: var(--sd-space-5);
  }

  .sd-mega__list {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    column-gap: var(--sd-grid-gutter);
  }

  .sd-mega__link {
    min-height: 4rem;    /* 64 — every cell the same height */
    padding-block: var(--sd-space-2);
    border-top: var(--sd-border-width) solid var(--sd-color-border-subtle);
    transition: border-color var(--sd-transition-feedback);
  }

  .sd-mega__link:hover { border-top-color: var(--sd-color-brand-blue); }

  .sd-mega__link-index {
    flex: none;
    width: 1.75rem;
    color: var(--sd-color-card-index);
    font-size: var(--sd-font-size-small);
    font-variant-numeric: tabular-nums;
  }

  .sd-mega__link-arrow {
    width: 1.125rem;
    height: 1.125rem;
    flex: none;
    color: var(--sd-color-brand-blue);
    opacity: 0;
    transform: translateX(-0.25rem);
    transition: opacity var(--sd-transition-feedback), transform var(--sd-transition-ui);
  }

  .sd-mega__link:hover .sd-mega__link-arrow,
  .sd-mega__link:focus-visible .sd-mega__link-arrow { opacity: 1; transform: none; }
}

/* ---------- Vertical dropdown with an introduction (≥ 1280px; owner choice F-09 A, Session 5.2) ---------- */

@media (min-width: 1280px) {
  .sd-mega {
    left: var(--sd-mega-left, 0px);
    right: auto;
    width: 40rem;
    border: var(--sd-border-width) solid var(--sd-color-border-subtle);
    border-radius: 0 0 var(--sd-radius-md) var(--sd-radius-md);
    overflow: hidden;
  }

  .sd-mega:has(.sd-mega__group + .sd-mega__group) { width: 46rem; }

  .sd-mega__inner {
    grid-template-columns: 15rem minmax(0, 1fr);
    column-gap: 0;
    max-width: none;
    margin: 0;
    padding: 0;
  }

  .sd-mega__intro {
    grid-column: auto;
    padding: var(--sd-space-5);
    border-right: var(--sd-border-width) solid var(--sd-color-border-subtle);
    background: var(--sd-color-surface-subtle);
  }

  .sd-mega__body {
    grid-column: auto;
    gap: var(--sd-space-3);
    padding: var(--sd-space-3);
  }

  .sd-mega__body:has(.sd-mega__group + .sd-mega__group) {
    grid-template-columns: 1fr 1fr;
    column-gap: var(--sd-space-3);
    align-items: start;
  }

  .sd-mega__group-title { margin: var(--sd-space-2) var(--sd-space-4) var(--sd-space-1); }

  .sd-mega__list { grid-template-columns: 1fr; }

  .sd-mega__link {
    min-height: 3rem;
    padding: var(--sd-space-2) var(--sd-space-4);
    border-top: 0;
    border-radius: var(--sd-radius-sm);
    transition: background-color var(--sd-transition-feedback);
  }

  .sd-mega__link:hover { background: var(--sd-color-blue-050); }
}

/* "Coming Soon" in copper (owner request F-09); text colour meets 4.5:1 (copper text token, Blueprint 3.14.1) */
.sd-mega__link-note--soon {
  color: var(--sd-color-text-accent);
  font-weight: var(--sd-font-weight-medium);
}

@keyframes sd-mega-in {
  from { opacity: 0; transform: translateY(-4px); }
  to { opacity: 1; transform: none; }
}

/* ---------- Drawer accordion (< 1280px) ---------- */

@media (max-width: 1279.98px) {
  .sd-mega { padding: 0 0 var(--sd-space-3) var(--sd-space-3); }

  .sd-mega__inner { display: grid; gap: 0; padding-inline: 0; }   /* no second page margin inside the drawer */

  /* Intro text, index numbers and arrows are desktop only */
  .sd-mega__title,
  .sd-mega__text,
  .sd-mega__link-index,
  .sd-mega__link-arrow { display: none; }

  .sd-mega__intro { display: contents; }
  .sd-mega__overview { order: -1; min-height: var(--sd-target-min); }

  .sd-mega__body { display: grid; }

  .sd-mega__group-title { margin: var(--sd-space-3) 0 var(--sd-space-1); }

  .sd-mega__link { min-height: var(--sd-target-min); padding-block: var(--sd-space-1); }

  /* Title and note on one line */
  .sd-mega__link-body { display: flex; flex-wrap: wrap; align-items: baseline; column-gap: var(--sd-space-2); }

  .sd-mega__link-title { font-size: 1rem; font-weight: var(--sd-font-weight-regular); color: var(--sd-color-text-default); }
  .sd-mega__link:hover .sd-mega__link-title { color: var(--sd-color-brand-blue); }
}