:root {
  color-scheme: light;
  --bg: #f6f8fb;
  --surface: #ffffff;
  --surface-muted: #eef2f7;
  --text: #172033;
  --muted: #5e6a7d;
  --link: #1456b8;
  --accent: #f56b16;
  --accent-dark: #c94d00;
  --blue: #1559bc;
  --border: #d9e0ea;
  --shadow: 0 14px 36px rgba(25, 42, 70, 0.09);
  --nav-shadow: 0 4px 18px rgba(18, 35, 61, 0.12);
}

body[data-theme="dark"] {
  color-scheme: dark;
  --bg: #0d1420;
  --surface: #151f2e;
  --surface-muted: #1d2a3b;
  --text: #edf3fb;
  --muted: #a7b4c5;
  --link: #8dbaff;
  --accent: #ff873f;
  --accent-dark: #ffad7d;
  --blue: #74a9ff;
  --border: #2a394d;
  --shadow: 0 14px 36px rgba(0, 0, 0, 0.24);
  --nav-shadow: 0 4px 18px rgba(0, 0, 0, 0.28);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  min-width: 320px;
  margin: 0;
  background:
    radial-gradient(circle at 0 0, rgba(245, 107, 22, 0.08), transparent 28rem),
    var(--bg);
  color: var(--text);
  font: 16px/1.65 "Segoe UI", Tahoma, Geneva, Verdana, sans-serif;
  transition: background 0.25s ease, color 0.25s ease;
}

body,
button,
a,
.card,
.site-nav,
footer,
table,
details {
  transition: background-color 0.25s ease, border-color 0.25s ease, color 0.25s ease;
}

a {
  color: var(--link);
  text-decoration: none;
}

a:hover {
  text-decoration: underline;
}

button {
  font: inherit;
}

.site-nav {
  position: sticky;
  top: 0;
  z-index: 20;
  background: linear-gradient(110deg, #f56b16 0%, #e65d13 35%, #1559bc 100%);
  box-shadow: var(--nav-shadow);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  max-width: 1100px;
  min-height: 64px;
  margin: 0 auto;
  padding: 0 1.25rem;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  color: #fff;
  font-size: 1.08rem;
  font-weight: 750;
  letter-spacing: 0.01em;
  white-space: nowrap;
}

.brand:hover {
  color: #fff;
  text-decoration: none;
}

.brand img {
  width: 34px;
  height: 34px;
  object-fit: contain;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 0.35rem;
}

.nav-links a,
.theme-toggle,
.menu-toggle {
  border: 1px solid transparent;
  border-radius: 999px;
  color: #fff;
}

.nav-links a {
  padding: 0.42rem 0.72rem;
  font-size: 0.95rem;
  font-weight: 600;
}

.nav-links a:hover,
.nav-links a[aria-current="page"] {
  background: rgba(255, 255, 255, 0.2);
  text-decoration: none;
}

.theme-toggle,
.menu-toggle {
  cursor: pointer;
  background: rgba(255, 255, 255, 0.14);
}

.theme-toggle {
  min-width: 2.45rem;
  margin-left: 0.25rem;
  padding: 0.38rem 0.64rem;
  font-size: 1rem;
}

.theme-toggle:hover,
.menu-toggle:hover {
  background: rgba(255, 255, 255, 0.28);
}

.menu-toggle {
  display: none;
  padding: 0.45rem 0.7rem;
  font-size: 1.3rem;
  line-height: 1;
}

.hero {
  color: #fff;
  background: linear-gradient(135deg, #f56b16, #1559bc);
}

.hero-inner,
.page-shell {
  max-width: 1100px;
  margin: 0 auto;
  padding-right: 1.25rem;
  padding-left: 1.25rem;
}

.hero-inner {
  padding-top: 3.7rem;
  padding-bottom: 3.7rem;
  text-align: center;
}

.hero h1,
.page-heading h1 {
  margin: 0;
  color: inherit;
  font-size: clamp(2rem, 4vw, 3.1rem);
  line-height: 1.12;
  letter-spacing: -0.035em;
}

.hero p {
  max-width: 680px;
  margin: 1rem auto 0;
  color: rgba(255, 255, 255, 0.9);
  font-size: 1.08rem;
}

.page-shell {
  padding-top: 2.5rem;
  padding-bottom: 4.5rem;
}

.page-heading {
  display: flex;
  align-items: end;
  justify-content: space-between;
  gap: 1.5rem;
  margin-bottom: 1.7rem;
}

.page-heading p {
  max-width: 680px;
  margin: 0.8rem 0 0;
  color: var(--muted);
}

.card,
.content-card {
  margin: 1.25rem 0;
  padding: clamp(1.25rem, 3vw, 2rem);
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
}

.content-card > :first-child {
  margin-top: 0;
}

.content-card > :last-child {
  margin-bottom: 0;
}

section {
  margin: 1.25rem 0;
}

h2,
h3,
h4 {
  color: var(--text);
  line-height: 1.25;
}

h2 {
  margin: 0 0 0.85rem;
  padding-bottom: 0.55rem;
  border-bottom: 2px solid var(--border);
  font-size: clamp(1.35rem, 2vw, 1.7rem);
}

h3 {
  margin-top: 1.8rem;
}

h4 {
  margin-bottom: 0.35rem;
}

p {
  margin: 0.7rem 0;
}

.highlight {
  color: var(--accent-dark);
  font-weight: 700;
}

body[data-theme="dark"] .highlight {
  color: var(--accent);
}

.button-link {
  display: inline-block;
  padding: 0.5rem 0.85rem;
  border: 1px solid var(--border);
  border-radius: 9px;
  background: var(--surface-muted);
  color: var(--text);
  font-weight: 650;
}

.button-link:hover {
  border-color: var(--accent);
  background: var(--accent);
  color: #fff;
  text-decoration: none;
}

.muted,
.note {
  color: var(--muted);
}

.note {
  font-size: 0.95rem;
}

.table-wrap {
  overflow-x: auto;
  margin: 1rem 0;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 12px;
  overflow: hidden;
}

thead th {
  background: var(--surface-muted);
  font-weight: 700;
}

th,
td {
  padding: 0.72rem 0.9rem;
  border-bottom: 1px solid var(--border);
  text-align: left;
  vertical-align: top;
}

tbody tr:last-child td {
  border-bottom: 0;
}

tbody tr:hover td {
  background: var(--surface-muted);
}

.site-footer {
  padding: 1.5rem 1.25rem;
  background: var(--surface-muted);
  color: var(--muted);
  text-align: center;
  font-size: 0.9rem;
}

/* FAQ */
.faq {
  counter-reset: item;
  margin: 0;
  padding: 0;
  list-style: none;
}

.faq > li {
  margin: 1.2rem 0 1.5rem;
}

.faq > li:last-child {
  margin-bottom: 0;
}

.question {
  display: inline-block;
  margin-bottom: 0.35rem;
  font-weight: 750;
}

.question::before {
  counter-increment: item;
  content: counter(item) ". ";
  color: var(--accent);
}

.answer p {
  margin: 0.35rem 0 0.6rem;
}

.footnotes {
  border-top: 1px dashed var(--border);
}

.footnotes ol {
  margin: 0.5rem 0 0;
  padding-left: 1.25rem;
}

.footnotes li {
  margin: 0.4rem 0;
}

.fn-ref {
  font-size: 0.85em;
  text-decoration: none;
  vertical-align: super;
}

.backref {
  margin-left: 0.5rem;
  text-decoration: none;
}

/* Meetings */
.meeting-list {
  display: grid;
  gap: 1.25rem;
}

.meeting-card {
  margin: 0;
  padding: 0;
  overflow: hidden;
}

.meeting-card summary {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  padding: 1.15rem 1.35rem;
  cursor: pointer;
  list-style: none;
  font-size: 1.15rem;
  font-weight: 750;
}

.meeting-card summary::-webkit-details-marker {
  display: none;
}

.meeting-card summary::after {
  color: var(--accent);
  content: "+";
  font-size: 1.5rem;
  line-height: 1;
}

.meeting-card[open] summary::after {
  content: "−";
}

.meeting-card summary:hover {
  background: var(--surface-muted);
}

.meeting-date {
  color: var(--muted);
  font-size: 0.9rem;
  font-weight: 500;
}

.meeting-files {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1rem;
  padding: 0 1.35rem 1.35rem;
}

.pdf-card {
  overflow: hidden;
  border: 1px solid var(--border);
  border-radius: 12px;
  background: var(--surface-muted);
}

.pdf-card header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 0.75rem;
  padding: 0.7rem 0.85rem;
}

.pdf-card h3 {
  margin: 0;
  font-size: 1rem;
}

.pdf-card iframe {
  display: block;
  width: 100%;
  height: 460px;
  border: 0;
  border-top: 1px solid var(--border);
  background: #fff;
}

.pdf-card .button-link {
  padding: 0.28rem 0.55rem;
  font-size: 0.82rem;
}

.empty-state {
  margin: 0;
  padding: 1.2rem;
  border: 1px dashed var(--border);
  border-radius: 12px;
  color: var(--muted);
}

/* Events */
.events-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
  gap: 1.25rem;
}

.event-card {
  overflow: hidden;
  margin: 0;
  padding: 0;
}

.event-card summary {
  position: relative;
  cursor: pointer;
  list-style: none;
}

.event-card summary::-webkit-details-marker {
  display: none;
}

.event-card summary::after {
  position: absolute;
  top: 1rem;
  right: 1rem;
  display: grid;
  width: 1.8rem;
  height: 1.8rem;
  place-items: center;
  border-radius: 50%;
  background: rgba(0, 0, 0, 0.35);
  color: #fff;
  content: "+";
  font-size: 1.35rem;
  line-height: 1;
}

.event-card[open] summary::after {
  content: "−";
}

.event-card summary:hover .event-summary-info {
  background: var(--surface-muted);
}

.event-summary-info {
  padding: 1rem 1.2rem;
  transition: background-color 0.25s ease;
}

.event-summary-info h2 {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 1.3rem;
}

.event-summary-info p {
  margin-bottom: 0;
}

.event-image,
.event-image-placeholder {
  display: block;
  width: 100%;
  aspect-ratio: 16 / 9;
  background: linear-gradient(135deg, rgba(245, 107, 22, 0.85), rgba(21, 89, 188, 0.9));
}

.event-image {
  object-fit: cover;
}

.event-image-placeholder {
  position: relative;
}

.event-image-placeholder::after {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  color: rgba(255, 255, 255, 0.9);
  content: "SIGARCH";
  font-size: 1.5rem;
  font-weight: 800;
  letter-spacing: 0.14em;
}

.event-content {
  display: flex;
  flex: 1;
  flex-direction: column;
  padding: 0 1.2rem 1.2rem;
}

.event-content h2 {
  margin: 0;
  padding: 0;
  border: 0;
  font-size: 1.35rem;
}

.event-meta {
  margin: 0.35rem 0 0;
  color: var(--accent-dark);
  font-size: 0.9rem;
  font-weight: 700;
}

body[data-theme="dark"] .event-meta {
  color: var(--accent);
}

.event-description {
  margin: 0.75rem 0 1rem;
  color: var(--muted);
}

.event-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.6rem;
  margin-top: auto;
  padding-top: 0.5rem;
}

.event-actions .button-link {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

.event-actions .button-link:hover {
  background: var(--accent-dark);
  border-color: var(--accent-dark);
}

.event-section + .event-section {
  margin-top: 2.5rem;
}

.event-section h2 {
  margin-bottom: 1rem;
}

.event-detail-card {
  max-width: 760px;
  margin-right: auto;
  margin-left: auto;
}

.event-detail-image {
  display: block;
  width: 100%;
  max-height: 520px;
  object-fit: contain;
  border-radius: 12px;
  background: var(--surface-muted);
}

.event-detail-card h1 {
  margin: 1.5rem 0 0;
  line-height: 1.15;
}

@media (max-width: 720px) {
  .nav-inner {
    min-height: 58px;
  }

  .menu-toggle {
    display: inline-block;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 58px;
    right: 0;
    left: 0;
    align-items: stretch;
    flex-direction: column;
    gap: 0.25rem;
    padding: 0.7rem 1.25rem 1rem;
    background: linear-gradient(155deg, #f56b16, #1559bc);
    box-shadow: var(--nav-shadow);
  }

  .nav-links.is-open {
    display: flex;
  }

  .nav-links a,
  .theme-toggle {
    width: 100%;
    border-radius: 9px;
    text-align: left;
  }

  .theme-toggle {
    margin: 0.25rem 0 0;
  }

  .hero-inner {
    padding-top: 2.8rem;
    padding-bottom: 2.8rem;
  }

  .page-shell {
    padding-top: 1.6rem;
    padding-bottom: 3rem;
  }

  .page-heading {
    display: block;
  }

  .meeting-files {
    grid-template-columns: 1fr;
  }

  .events-grid {
    grid-template-columns: 1fr;
  }

  .pdf-card iframe {
    height: 380px;
  }
}