/* ==========================================================================
   Site header — templates/partials/header.php, behaviour in /assets/js/nav.js
   --------------------------------------------------------------------------
   Solid (white) by default, `--overlay` = transparent over the home hero.
   State classes set by nav.js: `.is-ready` (JS running), `.is-solid`
   (overlay scrolled past the hero), `.is-open` (mobile menu open).
   ========================================================================== */

@layer components {
  .site-header {
    --header-fg: var(--neutral-800);
    --header-logo-fg: var(--neutral-600);
    --header-bg: var(--color-bg);

    position: sticky;
    inset-block-start: 0;
    z-index: 50;
    color: var(--header-fg);
    background-color: var(--header-bg);
    transition: background-color var(--duration-normal) var(--ease-standard),
                box-shadow var(--duration-normal) var(--ease-standard),
                color var(--duration-normal) var(--ease-standard);
  }

  /* Transparent over the hero. Without JS it simply scrolls away with the
     page (absolute), so white text never ends up over white content. */
  .site-header--overlay {
    --header-fg: var(--color-text-on-dark);
    --header-logo-fg: var(--color-text-on-dark);
    --header-bg: transparent;

    position: absolute;
    inset-inline: 0;
  }

  .site-header--overlay.is-ready {
    position: fixed;
  }

  .site-header--overlay.is-solid {
    --header-fg: var(--neutral-800);
    --header-logo-fg: var(--neutral-600);
    --header-bg: var(--color-bg);
  }

  .site-header.is-solid,
  .site-header.is-scrolled {
    box-shadow: var(--shadow-md);
  }

  .site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: var(--space-5);
    min-block-size: var(--header-height);
  }

  /* ----- Logo -------------------------------------------------------- */

  .site-header__logo {
    position: relative;
    z-index: 2;           /* stays above the open mobile panel */
    display: block;
    inline-size: var(--logo-width);
    flex: none;
    color: var(--header-logo-fg);
    border-radius: var(--radius-sm);
  }

  .logo {
    display: block;
    inline-size: 100%;
    block-size: auto;
    fill: currentColor;
  }

  .logo__kaars {
    fill: var(--color-brand);
  }

  /* ----- Desktop nav (≥ 68rem): panel dissolves into the header row --- */

  .site-nav {
    display: contents;
  }

  .site-nav__list {
    display: flex;
    align-items: center;
    gap: 1.875rem;
  }

  .site-nav__link {
    position: relative;
    display: inline-block;
    color: inherit;
    font-weight: var(--font-medium);
    text-decoration: none;
  }

  .site-nav__link::after {
    content: "";
    position: absolute;
    inset-inline-start: 0;
    inset-block-end: -0.3125rem;
    inline-size: 0;
    block-size: 2px;
    background-color: var(--color-brand);
    transition: inline-size var(--duration-normal) var(--ease-standard);
  }

  .site-nav__link:hover {
    color: inherit;
  }

  .site-nav__link:hover::after,
  .site-nav__link[aria-current="page"]::after {
    inline-size: 100%;
  }

  .site-nav__contact {
    display: flex;
    align-items: center;
    gap: 0.9375rem;
  }

  .site-nav__phone {
    display: inline-flex;
    align-items: center;
    gap: 0.9375rem;
    color: inherit;
    font-weight: var(--font-medium);
    text-decoration: none;
    white-space: nowrap;
    transition: opacity var(--duration-normal) var(--ease-standard);
  }

  .site-nav__phone .icon {
    --icon-size: 1.25rem;
    stroke-width: 1.5;
  }

  .site-nav__phone:hover {
    color: inherit;
    opacity: 0.8;
  }

  .site-header--overlay:not(.is-solid) :focus-visible {
    outline-color: var(--color-focus-ring-on-dark);
  }

  /* ----- Burger ------------------------------------------------------ */

  .site-header__toggle {
    position: relative;
    z-index: 2;
    display: none;
    place-items: center;
    inline-size: 2.75rem;
    block-size: 2.75rem;
    margin-inline-end: -0.5625rem;  /* optical: bars align with the gutter */
    padding: 0;
    color: inherit;
    background: none;
    border: 0;
    border-radius: var(--radius-sm);
    cursor: pointer;
  }

  .site-header__burger,
  .site-header__burger::before,
  .site-header__burger::after {
    display: block;
    inline-size: 1.5625rem;
    block-size: 3px;
    background-color: currentColor;
    transition: transform var(--duration-normal) var(--ease-standard),
                opacity var(--duration-normal) var(--ease-standard);
  }

  .site-header__burger {
    position: relative;
  }

  .site-header__burger::before,
  .site-header__burger::after {
    content: "";
    position: absolute;
    inset-inline-start: 0;
  }

  .site-header__burger::before { inset-block-start: -9px; }
  .site-header__burger::after  { inset-block-start: 9px; }

  .site-header.is-open .site-header__burger {
    background-color: transparent;
  }
  .site-header.is-open .site-header__burger::before {
    transform: translateY(9px) rotate(45deg);
  }
  .site-header.is-open .site-header__burger::after {
    transform: translateY(-9px) rotate(-45deg);
  }

  /* ----- Mobile (< 68rem): full-screen off-canvas panel -------------- */

  @media (max-width: 67.99rem) {
    :root {
      --header-height: 4.375rem;  /* 70px — also feeds scroll-padding-top */
    }

    .site-header {
      --logo-width: 15.625rem;
    }

    /* The off-canvas layout depends only on JS being on — decided by CSS at
       the first paint (not by nav.js adding a class later), so the header
       never renders as the tall no-JS fallback first (layout shift). */
    @media (scripting: enabled) {
      /* The burger (hidden in the markup for no-JS visitors) shows from the
         first paint, so nothing jumps when nav.js boots. */
      .site-header__toggle {
        display: grid;
      }

      .site-header .site-nav {
        position: fixed;
        inset: 0;
        z-index: 1;
        display: flex;
        flex-direction: column;
        padding: calc(var(--header-height) + 1.25rem) 1.875rem 1.875rem;
        overflow-y: auto;
        color: var(--neutral-800);
        background-color: var(--color-bg);
        transform: translateX(-100%);
        visibility: hidden;
        transition: transform var(--duration-normal) var(--ease-standard),
                    visibility 0s linear var(--duration-normal);
      }

      .site-header.is-open .site-nav {
        transform: none;
        visibility: visible;
        transition: transform var(--duration-normal) var(--ease-standard);
      }

      /* Open menu: logo + X switch to dark on the white panel */
      .site-header.is-open {
        --header-fg: var(--neutral-800);
        --header-logo-fg: var(--neutral-600);
      }

      .site-header .site-nav__list {
        flex-direction: column;
        align-items: stretch;
        gap: 1.5625rem;
      }

      .site-header .site-nav__list > li,
      .site-header .site-nav__contact {
        opacity: 0;
        transform: translateY(1.25rem);
        transition: opacity var(--duration-normal) var(--ease-standard),
                    transform var(--duration-normal) var(--ease-standard);
      }

      .site-header.is-open .site-nav__list > li,
      .site-header.is-open .site-nav__contact {
        opacity: 1;
        transform: none;
      }

      .site-header.is-open .site-nav__list > li:nth-child(1) { transition-delay: 100ms; }
      .site-header.is-open .site-nav__list > li:nth-child(2) { transition-delay: 150ms; }
      .site-header.is-open .site-nav__list > li:nth-child(3) { transition-delay: 200ms; }
      .site-header.is-open .site-nav__list > li:nth-child(4) { transition-delay: 250ms; }
      .site-header.is-open .site-nav__list > li:nth-child(5) { transition-delay: 300ms; }
      .site-header.is-open .site-nav__contact               { transition-delay: 350ms; }

      .site-header .site-nav__link {
        display: block;
        padding-block: 0.625rem;
        font-size: 1.5rem;
        border-block-end: 1px solid var(--neutral-300);
      }

      .site-header .site-nav__link::after {
        inset-block-end: 0.5625rem;
      }

      .site-header .site-nav__contact {
        flex-direction: column;
        align-items: stretch;
        gap: 1.25rem;
        margin-block-start: 2.5rem;
      }

      .site-header .site-nav__phone {
        gap: 0.625rem;
        font-size: var(--text-lg);
      }

      .site-header .site-nav__contact .btn {
        justify-content: center;
        padding: 0.9375rem 1.875rem;
        font-size: var(--text-base);
      }
    }

    @media (scripting: none) {
      /* No JS: no burger — the nav simply wraps under the logo. */
      .site-header .site-header__inner {
        flex-wrap: wrap;
        padding-block: var(--space-3);
      }

      .site-header .site-nav__main {
        flex-basis: 100%;
      }

      .site-header .site-nav__list,
      .site-header .site-nav__contact {
        flex-wrap: wrap;
        gap: var(--space-3) var(--space-5);
      }
    }
  }

  @media (max-width: 30rem) {
    .site-header {
      --logo-width: min(18.75rem, 100vw - 5.5rem);
    }

    @media (scripting: enabled) {
      .site-header .site-nav {
        padding-inline: 1.25rem;
      }

      .site-header .site-nav__link {
        font-size: var(--text-xl);
      }
    }
  }

  /* Body scroll lock while the mobile menu is open (class set by nav.js). */
  .has-open-nav {
    overflow: hidden;
  }

  @media (prefers-reduced-motion: reduce) {
    .site-header,
    .site-header *,
    .site-header *::before,
    .site-header *::after {
      transition-duration: 0s !important; /* override every staggered menu transition */
      transition-delay: 0s !important;
    }
  }

  /* Until nav.js has run (first frames): no menu transitions (see nav.js). */
  .site-header:not(.can-animate) :is(.site-nav, .site-nav__list > li, .site-nav__contact) {
    transition: none;
  }
}