/*
  Quarterbil Holding Limited: one-page holding-company site.
  Deliberately plain. Off-white background, one dark text colour,
  one muted accent for the link, a classic serif, lots of whitespace.
  No external fonts or scripts, so nothing is loaded from third parties.
*/

:root {
  --bg: #fbfaf7;        /* off-white page background */
  --text: #1f2328;      /* dark neutral for all text */
  --muted: #6b6f76;     /* lighter grey for the footer and wordmark */
  --accent: #4a5d6e;    /* muted slate blue, used only for the link */
  --rule: #e3e1dc;      /* thin divider lines */
}

* {
  box-sizing: border-box;
}

html {
  background: var(--bg);
}

body {
  margin: 0;
  font-family: Georgia, "Times New Roman", Times, serif;
  font-size: 1.125rem;
  line-height: 1.7;
  color: var(--text);
  /* The page colour comes from <html>; body stays see-through so the corner figure shows on narrow screens too */
  background: transparent;
  /* Centre a narrow reading column on any screen size */
  max-width: 40rem;
  padding: 0 1.5rem;
  margin-left: auto;
  margin-right: auto;
}

/* Needed so the decorative backdrop can be positioned against the whole page, not the narrow text column */
html {
  position: relative;
  overflow-x: hidden;
}

/* The faint faceted figure sits behind everything in the top-right corner of the page */
.backdrop {
  position: absolute;
  top: 0;
  right: 0;
  width: 26rem;
  height: 26rem;
  z-index: -1;
  pointer-events: none;
}

.site-header {
  padding: 2.5rem 0 1.5rem;
  position: relative;
  display: flex;
  align-items: center;
  gap: 0.9rem;
  flex-wrap: wrap;
}

.mark {
  width: 2.4rem;
  height: 2.4rem;
  flex-shrink: 0;
}

/*
  The divider under the header is drawn as a thin brushed-metal line:
  a left-to-right gradient that goes dark, light (the highlight), dark again.
*/
.site-header::after {
  content: "";
  display: block;
  width: 100%;      /* spans the full header width under mark and wordmark */
  height: 2px;
  margin-top: 1.5rem;
  background: linear-gradient(
    90deg,
    #6e7378 0%,
    #c9ccd0 35%,
    #f2f3f4 50%,
    #c9ccd0 65%,
    #6e7378 100%
  );
}

/*
  Metallic wordmark. The text itself is filled with a steel gradient
  (dark grey, pale highlight, dark grey) using background-clip, so no image
  is needed. The dark end colours keep it readable against the off-white page.
*/
.wordmark {
  margin: 0;
  font-size: 1.2rem;
  font-weight: bold;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: #4a4f55; /* fallback for very old browsers that cannot clip text */
  background: linear-gradient(
    180deg,
    #2f3338 0%,
    #5f656b 40%,
    #b9bdc1 50%,
    #5f656b 60%,
    #2f3338 100%
  );
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  /* A faint drop shadow adds the slight raised, engraved feel */
  filter: drop-shadow(0 1px 0 rgba(255, 255, 255, 0.8));
}

.content {
  padding: 3rem 0 4rem;
}

h1 {
  font-size: 2rem;
  font-weight: normal;
  line-height: 1.25;
  margin: 0 0 1.5rem;
}

h2 {
  font-size: 1.1rem;
  font-weight: bold;
  margin: 2.5rem 0 0.5rem;
}

p {
  margin: 0 0 1.25rem;
}

a {
  color: var(--accent);
  text-decoration: underline;
  text-underline-offset: 0.15em;
}

a:hover,
a:focus {
  color: var(--text);
}

/* Visible keyboard focus for accessibility */
a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

.site-footer {
  padding: 1.5rem 0 3rem;
  border-top: 1px solid var(--rule);
  font-size: 0.9rem;
  color: var(--muted);
}

.site-footer p {
  margin: 0;
}

/* Slightly tighter spacing on small phones */
@media (max-width: 480px) {
  body {
    font-size: 1.05rem;
  }

  h1 {
    font-size: 1.6rem;
  }

  .content {
    padding: 2rem 0 3rem;
  }

  /* Keep the faceted corner figure visible on phones: smaller, tucked into the top-right */
  .backdrop {
    width: 13rem;
    height: 13rem;
    right: -2.5rem;
    top: -1rem;
  }
}

/* Tablets and narrow laptops: figure a little smaller so it stays clear of the text column */
@media (min-width: 481px) and (max-width: 900px) {
  .backdrop {
    width: 18rem;
    height: 18rem;
    right: -4rem;
  }
}