/* References

   1. CSS Variables & Theming:
      - W3Schools: https://www.w3schools.com/css/css3_variables.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/Using_CSS_custom_properties
      - CSS-Tricks: https://css-tricks.com/guides/css-variables/

   2. Dark Mode:
      - W3Schools: https://www.w3schools.com/howto/howto_css_dark_mode.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/@media/prefers-color-scheme
      - CSS-Tricks: https://css-tricks.com/a-complete-guide-to-dark-mode-on-the-web/

   3. Layout & Flexbox:
      - W3Schools: https://www.w3schools.com/css/css3_flexbox.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Flexible_Box_Layout/Basic_Concepts_of_Flexbox
      - CSS-Tricks: https://css-tricks.com/snippets/css/a-guide-to-flexbox/

   4. Box Model, Padding, Margin, Borders, Shadow:
      - W3Schools: https://www.w3schools.com/css/css_box.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Learn/CSS/Building_blocks/The_box_model
      - CSS-Tricks: https://css-tricks.com/almanac/properties/b/box-shadow/

   5. Text & Fonts:
      - W3Schools: https://www.w3schools.com/css/css_font.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/font-family
      - CSS-Tricks: https://css-tricks.com/almanac/properties/f/font-family/

   6. Navigation & Links:
      - W3Schools: https://www.w3schools.com/css/css_link.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/:hover
      - CSS-Tricks: https://css-tricks.com/almanac/selectors/h/hover/

   7. Buttons & Interactive States:
      - W3Schools: https://www.w3schools.com/css/css_buttons.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Buttons
      - CSS-Tricks: https://css-tricks.com/snippets/css/styling-cross-browser-compatible-buttons/

   8. Forms & Inputs:
      - W3Schools: https://www.w3schools.com/css/css_form.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Learn/CSS/Styling_text_inputs
      - CSS-Tricks: https://css-tricks.com/snippets/css/styling-cross-browser-compatible-inputs/

   9. Responsive Design & Media Queries:
      - W3Schools: https://www.w3schools.com/css/css_rwd_mediaqueries.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/Media_Queries/Using_media_queries
      - CSS-Tricks: https://css-tricks.com/snippets/css/media-queries-for-standard-devices/

   10. Transitions & Hover Effects:
      - W3Schools: https://www.w3schools.com/css/css3_transitions.asp
      - MDN: https://developer.mozilla.org/en-US/docs/Web/CSS/CSS_Transitions/Using_CSS_transitions
      - CSS-Tricks: https://css-tricks.com/almanac/properties/t/transition/
*/

:root {
  --accent: #0d6efd;
  --radius: 10px;
  --gap: 18px;

  /* Light mode defaults */
  --bg: #82d2f3;
  --nav-bg: #77cceb;
  --text: #222;
  --muted: #666;
  --border: #e4e4e4;
  --search-bg: #ffffff;
  --shadow: 0 1px 0 rgba(0, 0, 0, 0.05);
}

/* Dark Mode */
body.dark-mode {
  --bg: #16191b;
  --nav-bg: #1b1f23;
  --text: #e5e5e5;
  --muted: #9ca2a8;
  --border: #2a2e31;
  --search-bg: #1f2326;
  --shadow: none;
}

body {
  background: var(--bg);
  color: var(--text);
  margin: 0;
  font-family: Inter, "Segoe UI", Roboto, Arial;
}

/* Header wrapper */
.site-header {
  width: 100%;
  border-bottom: 1px solid var(--border);
  background: var(--nav-bg);
  box-shadow: var(--shadow);
  padding: 16px 30px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  margin: 0 auto;
}

/* Header layout:
   Left = Logo
   Middle = Search
   Right = Nav
*/
.header-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  width: 100%;
}

/* NEW — Centre column for search box */
.header-middle {
  flex: 1;
  display: flex;
  justify-content: center;
}

/* If the page has no search bar, the middle column still keeps spacing */
.header-middle:empty {
  visibility: hidden;
  pointer-events: none;
}

/* Logo */
.logo-link {
  flex: 0 0 auto;
  display: flex;
  align-items: center;
}

.header-logo {
  height: 120px;
  width: auto;
  display: block;
}

/* Navigation */
.main-nav {
  display: flex;
  gap: 34px;
  align-items: center;
  justify-content: center;
  flex: 0 0 auto;
  /* don't stretch the nav */
  min-width: 0;
}

.nav-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 6px;
  text-decoration: none;
  color: var(--muted);
  padding: 6px 8px;
  border-radius: 10px;
  transition: 0.15s ease;
}

.nav-item:hover {
  color: var(--text);
  transform: translateY(-1px);
}

.nav-item.active {
  color: var(--text);
  border: 1.8px solid var(--accent);
  background: rgba(13, 110, 253, 0.08);
}

/* Nav icons */
.nav-item .nav-icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 28px;
  height: 28px;
  flex-shrink: 0;
  color: var(--muted);
}

.nav-item.active .nav-icon {
  color: var(--accent);
}

.nav-label {
  color: black;
}

/* Search container */
#search-container {
  width: 250px;
  display: flex;
  align-items: center;
  gap: 8px;
}

#search-input {
  flex: 1;
  min-width: 0;
  padding: 11px 14px;
  font-size: 14px;
  border-radius: 8px;
  border: 1px solid var(--border);
  background: var(--search-bg);
  color: var(--text);
}

#clear-search {
  background: transparent;
  border: none;
  font-size: 16px;
  cursor: pointer;
  display: none;
}

#search-container.has-text #clear-search {
  display: inline-block;
}

/* Default nav colours */
.nav-item {
  position: relative; /* required for pseudo-element border */
  z-index: 0;
}

.nav-item .nav-icon,
.nav-item .nav-label {
  color: #000;
  transition: color 0.2s ease; /* smooth hover */
}

/* Hover effect */
.nav-item:hover .nav-icon,
.nav-item:hover .nav-label {
  color: grey;
}

/* Light blue border effect */
.nav-item::before {
  content: "";
  position: absolute;
  top: -2px;
  left: -2px;
  right: -2px;
  bottom: -2px;
  border: 1px solid #00bfff; /* light blue border */
  border-radius: 4px; /* match your button corners if needed */
  box-shadow: 0 0 0 0 #00bfff; /* initial glow */
  transition: box-shadow 0.3s, transform 0.2s;
  z-index: -1; /* behind the button content */
}

.nav-item:hover::before {
  box-shadow: 0 0 10px 4px rgba(0, 191, 255, 0.4); /* subtle glow */
  transform: translateY(-2px); /* slight lift effect */
}

/* Dark mode nav colours */
body.dark-mode .nav-item .nav-icon,
body.dark-mode .nav-item .nav-label {
  color: #fff;
}

body.dark-mode .nav-item:hover .nav-icon,
body.dark-mode .nav-item:hover .nav-label {
  color: grey;
}

/* Dark mode border effect */
body.dark-mode .nav-item::before {
  border-color: #00bfff;
  box-shadow: 0 0 0 0 rgba(0, 191, 255, 0.2);
}

body.dark-mode .nav-item:hover::before {
  box-shadow: 0 0 10px 4px rgba(0, 191, 255, 0.4);
}

/* Desktop-specific layout */
@media (min-width: 901px) {
  .header-top {
    flex-direction: row;
  }
}

/* Mobile layout */
@media (max-width: 900px) {
  .header-top {
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    gap: 12px;
  }

  .main-nav {
    flex: 0 1 auto;
    gap: 16px;
    justify-content: center;
  }

  #search-container {
    width: auto;
    min-width: 200px;
    max-width: 250px;
  }
}