/* === Atlanta Tech Talks — Theme Variables === */
:root {
  --color-bg: #0f1117;
  --color-surface: #1a1d27;
  --color-surface-hover: #222531;
  --color-border: #2a2d3a;
  --color-text: #e4e4e7;
  --color-text-muted: #a1a1aa;
  --color-accent: #3b82f6;
  --color-accent-hover: #60a5fa;
  --color-accent-subtle: rgba(59, 130, 246, 0.12);
  --color-success: #22c55e;
  --color-warning: #eab308;
  --font-sans: system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  --font-mono: ui-monospace, "Cascadia Mono", "Segoe UI Mono", "Roboto Mono", Menlo, monospace;
  --radius: 8px;
  --max-width: 52rem;
}

/* === Reset === */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

/* === Base === */
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  background: var(--color-bg) url('../atltt.avif') no-repeat center top / cover fixed;
  color: var(--color-text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background: rgba(15, 17, 23, 0.92);
  z-index: -1;
}

a { color: var(--color-accent); text-decoration: none; }
a:hover { color: var(--color-accent-hover); text-decoration: underline; }
a:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; border-radius: 2px; }

img { max-width: 100%; display: block; }

/* === Skip link === */
.skip-link {
  position: absolute;
  top: -100%;
  left: 1rem;
  background: var(--color-accent);
  color: #fff;
  padding: .5rem 1rem;
  border-radius: var(--radius);
  z-index: 100;
  font-weight: 600;
}
.skip-link:focus { top: 1rem; }

/* === Layout === */
.container { max-width: var(--max-width); margin: 0 auto; padding: 0 1.5rem; }

/* === Header / Nav === */
.site-header {
  border-bottom: 1px solid var(--color-border);
  padding: 1rem 0;
}
.site-header .container {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
}
.site-logo {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--color-text);
  text-decoration: none;
  white-space: nowrap;
}
.site-logo:hover { color: var(--color-accent); text-decoration: none; }

.site-nav { display: flex; gap: .25rem; align-items: center; }
.site-nav a {
  color: var(--color-text-muted);
  padding: .4rem .75rem;
  border-radius: var(--radius);
  font-size: .9rem;
  transition: background .15s, color .15s;
}
.site-nav a:hover { background: var(--color-surface); color: var(--color-text); text-decoration: none; }
.site-nav a[aria-current="page"] { color: var(--color-accent); background: var(--color-accent-subtle); }

/* Mobile nav toggle */
.nav-toggle { display: none; background: none; border: none; color: var(--color-text); cursor: pointer; padding: .5rem; }

/* === Hero === */
.hero {
  padding: 2.5rem 0 2rem;
  text-align: center;
}
.hero h1 { font-size: 2rem; font-weight: 800; letter-spacing: -0.02em; margin-bottom: .5rem; }
.hero .tagline { color: var(--color-text-muted); font-size: 1.1rem; max-width: 36rem; margin: 0 auto .75rem; }
.hero .meta { color: var(--color-text-muted); font-size: .85rem; }
.hero .meta span + span::before { content: " · "; }

/* === Section headings === */
.section-heading {
  font-size: 1.25rem;
  font-weight: 700;
  margin: 2.5rem 0 1rem;
  padding-bottom: .5rem;
  border-bottom: 1px solid var(--color-border);
}

/* === Event Cards === */
.event-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  margin-bottom: 1rem;
  transition: border-color .15s;
  overflow: hidden;
}
.event-card:hover { border-color: var(--color-accent); }

.event-card.featured {
  border-color: var(--color-accent);
  background: linear-gradient(135deg, var(--color-accent-subtle) 0%, var(--color-surface) 60%);
}

.event-card-img {
  width: 100%;
  aspect-ratio: 4 / 1;
  object-fit: cover;
}
.event-card.featured .event-card-img { aspect-ratio: 16 / 5; }
.event-card-body { padding: 1.25rem; }

.event-date {
  display: block;
  font-size: .8rem;
  font-weight: 600;
  color: var(--color-accent);
  text-transform: uppercase;
  letter-spacing: .04em;
  margin-bottom: .25rem;
}
.event-title {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: .35rem;
}
.event-location {
  color: var(--color-text-muted);
  font-size: .85rem;
  margin-bottom: .5rem;
}
.event-desc {
  color: var(--color-text-muted);
  font-size: .9rem;
  margin-bottom: .75rem;
}
.event-footer {
  display: flex;
  align-items: center;
  gap: 1rem;
  flex-wrap: wrap;
}
.event-attendees {
  font-size: .8rem;
  color: var(--color-text-muted);
}

/* === Buttons === */
.btn {
  display: inline-block;
  font-family: var(--font-sans);
  font-size: 1rem;
  font-weight: 700;
  padding: .55rem 1.5rem;
  border-radius: var(--radius);
  border: none;
  cursor: pointer;
  transition: background .15s, transform .1s;
}
.btn:hover { text-decoration: none; }
.btn:active { transform: scale(0.98); }
.btn:focus-visible { outline: 2px solid var(--color-accent); outline-offset: 2px; }

.btn-primary { background: #2563eb; color: #fff; }
.btn-primary:hover { background: var(--color-accent); color: #fff; }

.btn-outline { background: transparent; color: var(--color-accent); border: 1px solid var(--color-border); }
.btn-outline:hover { border-color: var(--color-accent); background: var(--color-accent-subtle); }

/* === Resource links === */
.resource-list { display: flex; gap: .5rem; flex-wrap: wrap; }
.resource-link {
  font-size: .8rem;
  padding: .25rem .6rem;
  background: var(--color-accent-subtle);
  border-radius: 4px;
  color: var(--color-accent-hover);
}
.resource-link:hover { background: var(--color-accent); color: #fff; text-decoration: none; }

/* === Footer === */
.site-footer {
  border-top: 1px solid var(--color-border);
  padding: 2rem 0;
  margin-top: 3rem;
  text-align: center;
  color: var(--color-text-muted);
  font-size: .8rem;
}
.site-footer a { color: var(--color-text-muted); }
.site-footer a:hover { color: var(--color-accent); }

/* === Page titles & content sections === */
.page-title {
  font-size: 1.75rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  margin: 2.5rem 0 .5rem;
}
.page-intro {
  color: var(--color-text-muted);
  margin-bottom: 2rem;
}

.content-section {
  margin-bottom: 2rem;
}
.content-section h2 {
  font-size: 1.15rem;
  font-weight: 700;
  margin-bottom: .5rem;
  color: var(--color-text);
}
.content-section p {
  color: var(--color-text-muted);
  margin-bottom: .75rem;
}
.content-section p:last-child { margin-bottom: 0; }

.info-list {
  list-style: none;
  margin: 0 0 .75rem;
}
.info-list li {
  color: var(--color-text-muted);
  padding: .25rem 0;
}
.info-list li strong {
  color: var(--color-text);
}

/* === Resources page === */
.resource-section {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1.25rem;
  margin-bottom: 1rem;
}
.resource-event-title {
  font-size: 1.1rem;
  font-weight: 700;
  margin-bottom: .15rem;
}
.resource-event-date {
  font-size: .8rem;
  color: var(--color-text-muted);
  margin-bottom: .75rem;
}
.resource-items {
  list-style: none;
}
.resource-items li {
  padding: .3rem 0;
}
.resource-items a {
  color: var(--color-accent);
  font-size: .9rem;
}
.resource-items a:hover { color: var(--color-accent-hover); }

/* === Placeholder to prevent CLS === */
.events-placeholder {
  min-height: 18rem;
}

/* === Empty state === */
.empty-state {
  text-align: center;
  padding: 2rem;
  color: var(--color-text-muted);
  font-size: .95rem;
}

/* === Event Detail Page === */
.event-detail-img {
  width: 100%;
  aspect-ratio: 16 / 5;
  object-fit: cover;
  border-radius: var(--radius);
  margin-bottom: 1.5rem;
}
.event-detail-meta {
  color: var(--color-text-muted);
  font-size: .9rem;
  margin-bottom: .5rem;
}
.event-long-desc {
  margin: 1.5rem 0;
  line-height: 1.7;
}
.event-long-desc p {
  color: var(--color-text-muted);
  margin-bottom: 1rem;
}
.event-long-desc p:last-child { margin-bottom: 0; }

.speaker-card, .sponsor-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin-bottom: .75rem;
}
.speaker-card strong, .sponsor-card strong {
  display: block;
  margin-bottom: .25rem;
}
.speaker-card p, .sponsor-card p {
  color: var(--color-text-muted);
  font-size: .9rem;
  margin-bottom: .25rem;
}

.venue-info {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 1rem 1.25rem;
  margin-bottom: .75rem;
}
.venue-info strong { display: block; margin-bottom: .25rem; }
.venue-info p { color: var(--color-text-muted); font-size: .9rem; margin-bottom: .25rem; }
.venue-notes { font-style: italic; }

.back-link {
  margin-top: 2rem;
  margin-bottom: 1rem;
}
.back-link a {
  color: var(--color-text-muted);
  font-size: .9rem;
}
.back-link a:hover { color: var(--color-accent); }

.event-card-link {
  color: inherit;
  text-decoration: none;
}
.event-card-link:hover { text-decoration: none; }

/* === Responsive === */
@media (max-width: 640px) {
  .hero h1 { font-size: 1.5rem; }
  .hero .tagline { font-size: 1rem; }

  .nav-toggle { display: block; }
  .site-nav {
    display: none;
    position: absolute;
    top: 100%;
    right: 1.5rem;
    background: var(--color-surface);
    border: 1px solid var(--color-border);
    border-radius: var(--radius);
    flex-direction: column;
    padding: .5rem;
    min-width: 10rem;
    z-index: 50;
  }
  .site-nav.open { display: flex; }
  .site-header .container { position: relative; }
}