/* =========================================================================
   A Talk About Giving Talks — stylesheet
   Green palette, professional, high-contrast typography. No animations.
   ========================================================================= */

:root {
  --font-sans: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  --font-serif: Georgia, Cambria, "Times New Roman", Times, serif;

  --color-bg: #ffffff;
  --color-surface: #f1f6f2;
  --color-border: #d7e4db;
  --color-text: #16201a;
  --color-muted: #55655b;
  --color-accent: #15803d;
  --color-accent-contrast: #ffffff;

  --measure: 42rem;      /* comfortable reading width */
  --radius: 8px;
  --space: 1rem;
}

@media (prefers-color-scheme: dark) {
  :root {
    --color-bg: #111814;
    --color-surface: #18211c;
    --color-border: #2a382f;
    --color-text: #e7ede9;
    --color-muted: #97a89e;
    --color-accent: #57c07b;
    --color-accent-contrast: #0a120d;
  }
}

/* --- Reset-ish ---------------------------------------------------------- */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body {
  margin: 0;
  font-family: var(--font-sans);
  font-size: 1.0625rem;
  line-height: 1.65;
  color: var(--color-text);
  background: var(--color-bg);
}
img { max-width: 100%; height: auto; }
a { color: var(--color-accent); text-decoration: underline; text-underline-offset: 2px; }
a:hover { text-decoration: none; }

.container { width: 100%; max-width: 60rem; margin: 0 auto; padding: 0 1.25rem; }

.skip-link {
  position: absolute; left: -999px; top: 0;
  background: var(--color-accent); color: var(--color-accent-contrast);
  padding: .5rem .75rem; border-radius: 0 0 var(--radius) 0; z-index: 10;
}
.skip-link:focus { left: 0; }

/* --- Header ------------------------------------------------------------- */
.site-header {
  border-bottom: 1px solid var(--color-border);
  background: var(--color-bg);
}
.site-header__inner {
  display: flex; flex-wrap: wrap; align-items: baseline;
  justify-content: space-between; gap: .5rem 1.5rem;
  padding-top: 1rem; padding-bottom: 1rem;
}
.site-header__title {
  font-weight: 700; font-size: 1.05rem; letter-spacing: -0.01em;
  color: var(--color-text); text-decoration: none;
}
.site-nav { display: flex; gap: 1.25rem; font-size: .95rem; }
.site-nav a { color: var(--color-muted); text-decoration: none; }
.site-nav a:hover { color: var(--color-accent); text-decoration: underline; }

/* --- Main / generic ----------------------------------------------------- */
main { padding: 2.5rem 0 3rem; }
h1, h2, h3 { line-height: 1.25; letter-spacing: -0.015em; }

/* --- Landing page ------------------------------------------------------- */
.intro { max-width: var(--measure); margin-bottom: 2.5rem; }
.intro__title { font-size: 2.1rem; margin: 0 0 .75rem; }
.intro__lead { font-size: 1.15rem; color: var(--color-muted); margin: 0 0 1.5rem; }

.button {
  display: inline-block; background: var(--color-accent);
  color: var(--color-accent-contrast); text-decoration: none;
  padding: .6rem 1.1rem; border-radius: var(--radius); font-weight: 600;
}
.button:hover { text-decoration: none; opacity: .92; }

.section-group { margin: 0 0 2.75rem; }
.section-group__title {
  font-size: 1.4rem; margin: 0 0 .35rem;
  padding-bottom: .4rem; border-bottom: 2px solid var(--color-border);
}
.section-group__blurb { color: var(--color-muted); margin: .5rem 0 1.1rem; max-width: var(--measure); }

.card-list {
  list-style: none; margin: 0; padding: 0;
  display: grid; gap: .75rem;
  grid-template-columns: repeat(auto-fill, minmax(15rem, 1fr));
}
.card { margin: 0; }
.card__link {
  display: flex; align-items: baseline; justify-content: space-between; gap: .75rem;
  height: 100%; padding: .85rem 1rem;
  background: var(--color-surface); border: 1px solid var(--color-border);
  border-radius: var(--radius); text-decoration: none; color: var(--color-text);
}
.card__link:hover { border-color: var(--color-accent); text-decoration: none; }
.card__title { font-weight: 600; }
.card__meta { color: var(--color-muted); font-size: .85rem; font-variant-numeric: tabular-nums; white-space: nowrap; }

/* --- Talk page ---------------------------------------------------------- */
.talk { max-width: var(--measure); }
.breadcrumb { font-size: .9rem; color: var(--color-muted); margin-bottom: 1.25rem; }
.breadcrumb a { color: var(--color-muted); }
.breadcrumb span { margin: 0 .4rem; }

.talk__section {
  text-transform: uppercase; letter-spacing: .08em; font-size: .75rem;
  font-weight: 700; color: var(--color-accent); margin: 0 0 .35rem;
}
.talk__title { font-size: 2rem; margin: 0 0 1rem; }

.watch-link {
  display: inline-block; text-decoration: none; font-weight: 600;
  color: var(--color-accent); font-variant-numeric: tabular-nums;
}
.watch-link:hover { text-decoration: underline; }
.talk__watch { margin: 0 0 1.5rem; }

.video {
  position: relative; width: 100%; aspect-ratio: 16 / 9;
  margin: 0 0 1.75rem; background: #000;
  border: 1px solid var(--color-border); border-radius: var(--radius); overflow: hidden;
}
.video iframe { position: absolute; inset: 0; width: 100%; height: 100%; border: 0; }

.slide-figure { margin: 0 0 1.75rem; }
.slide-figure img { border: 1px solid var(--color-border); border-radius: var(--radius); display: block; }
.slide-figure figcaption { color: var(--color-muted); font-size: .9rem; margin-top: .5rem; }

.talk__body { font-size: 1.1rem; }
.talk__body p { margin: 0 0 1.15rem; }
.talk__body h2 { font-size: 1.3rem; margin: 2rem 0 .75rem; }
.talk__body ul, .talk__body ol { margin: 0 0 1.15rem; padding-left: 1.4rem; }
.talk__body li { margin-bottom: .4rem; }
.talk__body blockquote {
  margin: 1.5rem 0; padding: .25rem 0 .25rem 1.1rem;
  border-left: 3px solid var(--color-accent); color: var(--color-muted); font-style: italic;
}

/* --- Pager -------------------------------------------------------------- */
.pager {
  display: flex; gap: 1rem; margin-top: 3rem;
  padding-top: 1.5rem; border-top: 1px solid var(--color-border);
}
.pager__prev, .pager__next { flex: 1 1 50%; }
.pager__next { text-align: right; }
.pager a {
  display: inline-flex; flex-direction: column; gap: .15rem;
  text-decoration: none; color: var(--color-text);
}
.pager a:hover .pager__title { text-decoration: underline; }
.pager__label { font-size: .8rem; color: var(--color-muted); }
.pager__title { font-weight: 600; }

/* --- Footer ------------------------------------------------------------- */
.site-footer {
  border-top: 1px solid var(--color-border);
  background: var(--color-surface);
  padding: 2rem 0; margin-top: 2rem;
  font-size: .95rem; color: var(--color-muted);
}
.site-footer__about { margin: 0 0 .75rem; max-width: var(--measure); }
.site-footer__links { list-style: none; display: flex; flex-wrap: wrap; gap: 1.25rem; margin: 0; padding: 0; }

@media (max-width: 32rem) {
  .intro__title { font-size: 1.75rem; }
  .talk__title { font-size: 1.6rem; }
  .pager a { gap: 0; }
}