/* nav.css */
/* jdtoolonline.com */
/* July 20th, 2026 */

/* Skip link */

.skip-link {
  position: fixed;
  top: -100px;
  left: 0;
  z-index: 1000;
  background-color: var(--color-primary);
  color: var(--color-text-cta);
  padding: 12px 20px;
  font-weight: bold;
  text-decoration: none;
  transition: var(--transition-header-speed);
}

.skip-link:focus {
  top: 0;
}

/* Header */

header {
  position: fixed;
  top: 0;
  box-sizing: border-box;
  width: 100%;
  background-color: var(--color-footer-primary);
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.4);
}

.header-content-wrapper {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--padding-header-top) var(--content-edge-spacing) var(--padding-header-bottom);
  max-width: var(--max-page-width);
  height: var(--height-header);
  margin-left: auto;
  margin-right: auto;
}

.header-buttons-wrapper {
  display: flex;
  align-items: center;
  margin-left: auto;
}

/* TODO: Put a wrapper to limit how much the header content can move on large screens */

/* Navigation */

header nav ul {
  display: flex;
  gap: 2rem;
}

header nav a {
  font-size: 18px;
  font-weight: bold;
}

nav a {
  text-decoration: none;
  transition: var(--transition-header-speed);
}

nav ul {
  list-style: none;
  margin: 0px;
  padding: 0px;
}

/* Logo */

header .logo {
  height: 45px;
  transition: var(--transition-header-speed);
}

header .logo:hover {
  box-shadow: var(--glow-hover);
}

/* CTA Button */
header .cta-button {
  margin-left: 30px;
  margin-top: 0px;
}

main {
  padding-top: calc(var(--padding-header-top) + var(--padding-header-bottom) + var(--height-header));
}

/* Mobile */

/* Not in the tab order at desktop sizes - the hamburger button it controls
   is display:none there too, so leaving it focusable would create a stray,
   invisible tab stop between the logo and the nav links. It's restored
   (visually hidden but still focusable/operable via keyboard - native
   checkbox Space-toggle) inside the mobile media query below, where the
   hamburger button actually becomes visible. Do not use the `hidden`
   attribute for the mobile state, that removes it from the tab order
   entirely regardless of screen size. */
.menu-toggle {
  display: none;
}

.menu-toggle:focus-visible + .hamburger-button {
  outline: 2px solid var(--color-primary);
  outline-offset: 2px;
}

.hamburger-button {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  align-items: center;
  margin-left: auto;
  flex-shrink: 0;
  border: none;
  height: 24px;
  width: 30px;
  padding: 0px;
  background-color: transparent;
  cursor: pointer;
}

.hamburger-line {
  height: 3px;
  width: 100%;
  border-radius: 2px;
  background-color: var(--color-text);
  transition: var(--transition-hamburger-speed);
}

.hamburger-button:hover .hamburger-line {
  background-color: var(--color-text-hover);
}

/* Animation when toggled */

/* Top Hamburger Line */
.menu-toggle:checked + .hamburger-button .hamburger-line:nth-child(1) {
  transform: translateY(10.5px) rotate(45deg);
  transform-origin: center;
}
/* Middle Hamburger Line */
/* background-color instead of opacity: WebKit can leave faint artifacts at
   this line's rounded corners when fading via opacity while the other two
   lines are simultaneously transforming. */
.menu-toggle:checked + .hamburger-button .hamburger-line:nth-child(2) {
  background-color: transparent;
}
/* Bottom Hamburger Line */
.menu-toggle:checked + .hamburger-button .hamburger-line:nth-child(3) {
  transform: translateY(-10.5px) rotate(-45deg);
  transform-origin: center;
}

/* TODO: Make variable */
@media (max-width: 46rem) { /* 620px */

  .menu-toggle {
    display: block;
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border: 0;
  }

  .hamburger-button {
    display: flex;
  }

  /* Stays in the DOM (not display:none) so height can be transitioned -
     display can't be animated. Collapsed via max-height:0 plus
     overflow:hidden, and visibility:hidden keeps its links out of the tab
     order while closed (overflow:hidden alone would still allow keyboard
     focus to land on them). visibility flips instantly on open but only
     after the close transition finishes, via the delay below.
     max-height (a fixed guess, generous enough not to clip a reasonable
     number of links) is the universal fallback here, since animating to/
     from height:auto isn't supported everywhere yet. The @supports block
     below upgrades to the exact, always-correct height:auto version in
     browsers that do support it. */
  .header-buttons-wrapper {
    display: flex;
    align-items: start;
    justify-content: center;
    position: fixed;
    top: calc(var(--height-header) + var(--padding-header-bottom) + var(--padding-header-top));
    left: 0px;
    right: 0px;
    background-color: var(--color-footer-secondary);
    overflow: hidden;
    max-height: 0;
    visibility: hidden;
    transition: max-height var(--transition-header-speed) ease,
                visibility 0s linear var(--transition-header-speed);
  }

  /* Hamburger Menu Checkbox is Checked */

  .menu-toggle:checked ~ .header-buttons-wrapper {
    max-height: 500px;
    visibility: visible;
    transition: max-height var(--transition-header-speed) ease, visibility 0s;
  }

  /* Upgrade to animating the exact content height where supported, so this
     always matches however many links are actually in the list instead of
     the fixed max-height guess above. */
  @supports (interpolate-size: allow-keywords) {

    .header-buttons-wrapper {
      interpolate-size: allow-keywords;
      max-height: none;
      height: 0;
      transition: height var(--transition-header-speed) ease,
                  visibility 0s linear var(--transition-header-speed);
    }

    .menu-toggle:checked ~ .header-buttons-wrapper {
      max-height: none;
      height: auto;
      transition: height var(--transition-header-speed) ease, visibility 0s;
    }

  }

  /* Unconditional (not gated behind :checked) since .header-buttons-wrapper
     stays rendered while closed now - if this stayed :checked-only, the
     column layout would snap back to the desktop row layout the instant
     the box is unchecked, flashing a row for the whole closing transition. */
  .header-buttons-wrapper nav {
    width: 100%;
  }

  .header-buttons-wrapper nav ul {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: unset;
    justify-content: flex-end;
    width: 100%;
    margin: 0;
    padding: 0;
    text-align: center;
  }

  .header-buttons-wrapper nav li {
    width: 100%;
  }

  .header-buttons-wrapper nav a {
    display: block;
    width: 90%;
    margin: 0 auto;
    padding: 20px 0;
    border-bottom: 0.5px solid var(--color-text-hover);
  }

  .header-buttons-wrapper nav li:last-child a {
    border-bottom: none;
  }

  /* TODO: Set mobile nav a background-color on hover */

  header .cta-button {
    display: none;
  }

}