/*
  Documentation (CSS):
  - Provides formatting for layout, figure captions, thumbnail sizing
  - Demonstrates list-style-image (custom external icon) and list-style-type
  - Contains comments per assignment requirements
*/

/* Base */
:root {
  --maxw: 960px;
  --bg: #0b1220;
  --paper: #ffffff;
  --ink: #1d2433;
  --muted: #55607a;
  --accent: #2e7dd7;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: system-ui, -apple-system, Segoe UI, Roboto, "Helvetica Neue", Arial, sans-serif;
  line-height: 1.55;
}

header.hero {
  background: linear-gradient(180deg, #e8f0ff 0%, #f7faff 100%);
  border-bottom: 1px solid #e4e8f0;
  padding: 2.25rem 1rem;
}

h1, h2, h3 {
  margin: 0 0 0.5rem;
}

h1 {
  font-size: 2rem;
  color: #0b3b85;
}
h2 { margin-top: 2rem; color: #0f2b57; }
h3 { margin-top: 1rem; color: #143a7b; }

main {
  max-width: var(--maxw);
  margin: 1rem auto 3rem;
  padding: 0 1rem;
  background: var(--paper);
  border-radius: 14px;
  box-shadow: 0 6px 24px rgba(0,0,0,.08);
  padding-bottom: 2rem;
}

p.caption, .caption { color: var(--muted); font-size: 0.95rem; }
p.note { font-size: 0.9rem; color: var(--muted); }
.small { font-size: 0.9rem; color: var(--muted); }

/* Figure/thumbnail */
.figure { margin: 0; }
.thumb-link { text-decoration: none; color: inherit; }
.thumb {
  /* Resize image (thumbnail) via CSS */
  max-width: 360px;
  width: 100%;
  height: auto;
  border-radius: 10px;
  border: 1px solid #e4e8f0;
  box-shadow: 0 4px 16px rgba(0,0,0,.08);
}
.gif-demo {
  border-radius: 10px;
  border: 1px solid #e4e8f0;
}

/* Image aligned next to text (float wrapping example) */
.inline-img.align-right {
  float: right;
  margin: 0 0 0.5rem 1rem; /* space between image and text */
}
.clear { clear: both; }

/* Lists */
.list-wrap {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.25rem;
  align-items: start;
}

/* Customized markers with list-style-image (external URL as required) */
.star-list {
  /* Example using provided iconfinder URL */
  list-style-image: url("https://cdn0.iconfinder.com/data/icons/typicons-2/24/star-64.png");
  padding-left: 1.75rem; /* space to the left of markers */
}

/* Built-in marker styles (list-style-type) */
.builtin-list {
  list-style-type: square; /* show usage of list-style-type */
  padding-left: 1.25rem;
}

/* Media elements */
audio, video {
  margin-top: 0.5rem;
  width: 100%;
  max-width: 520px;
  display: block;
}

/* Attribution block */
.attribution {
  border-top: 1px solid #edf0f6;
  margin-top: 2rem;
  padding-top: 1rem;
}
.attribution ul {
  margin: 0.5rem 0 0;
}
.attribution li + li { margin-top: 0.35rem; }

/* Footer */
.footer {
  max-width: var(--maxw);
  margin: 0.5rem auto 3rem;
  padding: 0 1rem;
  color: #d9e1f2;
  text-align: center;
  font-size: 0.9rem;
}