/* =========================================================
   ICOCO 2026 — site stylesheet
   Single stylesheet for the whole site.
   Sections (search by /* === ): RESET, TOKENS, BASE,
   LAYOUT, NAV, HERO, BUTTONS, CARDS, TABLES, SECTIONS,
   FOOTER, UTILITIES, RESPONSIVE.
   ========================================================= */

/* === RESET ============================================== */
*, *::before, *::after { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }
body, h1, h2, h3, h4, p, ul, ol, figure, table { margin: 0; }
ul, ol { padding: 0; list-style: none; }
img { max-width: 100%; height: auto; display: block; }
a { color: inherit; }
button { font: inherit; }

/* === TOKENS ============================================= */
:root {
  /* IEEE blue palette + neutrals */
  --c-ink:        #0b1e3b;
  --c-ink-2:      #1f3563;
  --c-accent:     #00629b;   /* IEEE blue */
  --c-accent-2:   #00467f;
  --c-cta:        #f29100;   /* warm CTA */
  --c-cta-ink:    #1a1100;
  --c-bg:         #ffffff;
  --c-bg-soft:    #f4f6fb;
  --c-bg-band:    #eaf0fa;
  --c-line:       #d9def0;
  --c-mute:       #5b6781;
  --c-good:       #1f7a4a;

  --radius:       10px;
  --radius-sm:    6px;
  --shadow:       0 1px 2px rgba(11,30,59,.06), 0 6px 24px rgba(11,30,59,.06);

  --space-1: 4px;
  --space-2: 8px;
  --space-3: 12px;
  --space-4: 16px;
  --space-5: 24px;
  --space-6: 32px;
  --space-7: 48px;
  --space-8: 72px;

  --w-content: 1080px;

  --font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto,
               "Helvetica Neue", Arial, "Noto Sans", sans-serif;
  --font-mono: ui-monospace, SFMono-Regular, Menlo, Consolas, monospace;
}

/* === BASE =============================================== */
html { scroll-behavior: smooth; }
body {
  font-family: var(--font-sans);
  color: var(--c-ink);
  background: var(--c-bg);
  line-height: 1.55;
  font-size: 17px;
}
h1, h2, h3, h4 {
  color: var(--c-ink);
  line-height: 1.2;
  font-weight: 700;
  letter-spacing: -0.01em;
}
h1 { font-size: clamp(2rem, 4vw, 2.75rem); }
h2 { font-size: clamp(1.5rem, 2.5vw, 2rem); margin-top: var(--space-7); }
h3 { font-size: 1.25rem; margin-top: var(--space-5); }
p  { margin-top: var(--space-3); }
a  { color: var(--c-accent); text-decoration: underline; text-decoration-thickness: 1px; text-underline-offset: 2px; }
a:hover { color: var(--c-accent-2); }
strong { font-weight: 600; }
:focus-visible {
  outline: 3px solid var(--c-cta);
  outline-offset: 2px;
  border-radius: var(--radius-sm);
}

/* === LAYOUT ============================================= */
.container {
  width: 100%;
  max-width: var(--w-content);
  margin: 0 auto;
  padding: 0 var(--space-5);
}
main { display: block; }
section { padding-block: var(--space-7); }
section.band { background: var(--c-bg-soft); }
.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--c-ink);
  color: #fff;
  padding: var(--space-2) var(--space-4);
  z-index: 100;
}
.skip-link:focus-visible { left: var(--space-3); top: var(--space-3); }

/* === NAV ================================================ */
.site-nav {
  position: sticky;
  top: 0;
  z-index: 50;
  background: rgba(255,255,255,.92);
  backdrop-filter: saturate(160%) blur(8px);
  border-bottom: 1px solid var(--c-line);
}
.site-nav__inner {
  display: flex;
  align-items: center;
  gap: var(--space-5);
  padding-block: var(--space-3);
  width: 100%;
  max-width: var(--w-content);
  margin: 0 auto;
  padding-inline: var(--space-5);
}
.site-nav__brand {
  font-weight: 700;
  letter-spacing: -0.01em;
  text-decoration: none;
  color: var(--c-ink);
  display: flex;
  align-items: center;
  gap: var(--space-2);
  white-space: nowrap;
}
.site-nav__brand b { color: var(--c-accent); }
.site-nav__menu {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-4);
  margin-left: auto;
}
.site-nav__menu a {
  text-decoration: none;
  color: var(--c-ink-2);
  padding: var(--space-2) var(--space-2);
  border-radius: var(--radius-sm);
  font-weight: 500;
}
.site-nav__menu a[aria-current="page"] {
  color: var(--c-accent);
  background: var(--c-bg-band);
}
.site-nav__menu a:hover { color: var(--c-accent-2); }

/* mobile nav uses <details> — no JS */
.site-nav__toggle { display: none; }
@media (max-width: 768px) {
  .site-nav__inner { flex-wrap: wrap; }
  .site-nav__toggle {
    display: inline-block;
    margin-left: auto;
  }
  .site-nav__toggle summary {
    list-style: none;
    cursor: pointer;
    padding: var(--space-2) var(--space-3);
    border: 1px solid var(--c-line);
    border-radius: var(--radius-sm);
    background: var(--c-bg-soft);
    font-weight: 600;
  }
  .site-nav__toggle summary::-webkit-details-marker { display: none; }
  .site-nav__menu {
    display: none;
    width: 100%;
    flex-direction: column;
    gap: 0;
    margin: var(--space-3) 0 0 0;
    border-top: 1px solid var(--c-line);
    padding-top: var(--space-2);
  }
  .site-nav__toggle[open] + .site-nav__menu { display: flex; }
  .site-nav__menu a { padding-block: var(--space-3); }
}

/* === HERO =============================================== */
.hero {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  padding-block: clamp(var(--space-8), 12vw, 140px);
  color: #fff;
}
.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("../img/hero-bg.svg");
  background-size: cover;
  background-position: center;
  z-index: -2;
}
.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(60% 50% at 25% 60%, rgba(11,30,59,.62) 0%, rgba(11,30,59,0) 70%),
    linear-gradient(180deg, rgba(11,30,59,.35) 0%, rgba(11,30,59,.10) 60%, rgba(11,30,59,.55) 100%);
  z-index: -1;
}
.hero__inner { display: grid; grid-template-columns: 1.4fr 1fr; gap: var(--space-7); align-items: center; }
@media (max-width: 900px) { .hero__inner { grid-template-columns: 1fr; } }

.hero h1 {
  color: #fff;
  font-size: clamp(2.25rem, 5.5vw, 4rem);
  letter-spacing: -0.02em;
  text-wrap: balance;
}
.hero .lead { color: #e6ecfa; max-width: 56ch; }

.hero__eyebrow {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  background: rgba(255,255,255,.10);
  backdrop-filter: blur(6px);
  border: 1px solid rgba(255,255,255,.25);
  border-radius: 999px;
  padding: 6px 14px;
  font-size: 0.78rem;
  font-weight: 700;
  color: #fff7d6;
  text-transform: uppercase;
  letter-spacing: .12em;
}
.hero__eyebrow::before {
  content: "";
  width: 8px; height: 8px;
  border-radius: 50%;
  background: var(--c-cta);
  box-shadow: 0 0 12px var(--c-cta);
}
.hero__meta {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
  gap: var(--space-4);
  margin-top: var(--space-6);
  color: #fff;
  font-weight: 600;
}
.hero__meta span {
  background: rgba(255,255,255,.08);
  backdrop-filter: blur(8px);
  border: 1px solid rgba(255,255,255,.18);
  border-radius: var(--radius);
  padding: var(--space-3) var(--space-4);
}
.hero__meta span b {
  display: block;
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: #ffd07a;
  margin-bottom: 4px;
  font-weight: 700;
}
.hero__cta {
  margin-top: var(--space-6);
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-3);
}

/* === PAGE HERO (inner pages) ============================ */
.page-hero {
  position: relative;
  overflow: hidden;
  isolation: isolate;
  padding-block: clamp(var(--space-7), 8vw, 110px);
  color: #fff;
  background: linear-gradient(135deg, #0b1e3b 0%, #1f3563 55%, #00629b 100%);
}
.page-hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    radial-gradient(60% 60% at 88% 25%, rgba(242,145,0,.20) 0%, transparent 60%),
    radial-gradient(45% 70% at 12% 80%, rgba(0,98,155,.45) 0%, transparent 70%);
  pointer-events: none;
  z-index: -1;
}
.page-hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(205,214,232,0.08) 1px, transparent 1px),
    linear-gradient(90deg, rgba(205,214,232,0.08) 1px, transparent 1px);
  background-size: 80px 80px;
  pointer-events: none;
  z-index: -1;
  mask-image: radial-gradient(80% 100% at 50% 50%, #000 30%, transparent 100%);
  -webkit-mask-image: radial-gradient(80% 100% at 50% 50%, #000 30%, transparent 100%);
}
.page-hero h1 {
  color: #fff;
  font-size: clamp(2rem, 4.5vw, 3.25rem);
  margin-top: var(--space-3);
  letter-spacing: -0.02em;
  text-wrap: balance;
}
.page-hero .lead {
  color: #cdd6e8;
  max-width: 62ch;
  margin-top: var(--space-3);
}
.page-hero .tag {
  background: rgba(255,255,255,.10);
  color: #ffd07a;
  border: 1px solid rgba(255,255,255,.20);
  backdrop-filter: blur(6px);
}

/* === COUNTDOWN ========================================== */
.hero__countdowns {
  display: flex;
  flex-direction: column;
  gap: var(--space-3);
}
.countdown {
  background: linear-gradient(135deg, rgba(255,255,255,.12) 0%, rgba(255,255,255,.04) 100%);
  border: 1px solid rgba(255,255,255,.20);
  border-radius: var(--radius);
  padding: var(--space-5) var(--space-6);
  text-align: center;
  color: #fff;
  backdrop-filter: blur(10px);
  box-shadow: 0 10px 40px rgba(0,0,0,.25);
}
.countdown__num {
  font-size: clamp(3.5rem, 9vw, 6rem);
  font-weight: 800;
  line-height: 1;
  background: linear-gradient(180deg, #fff7d6 0%, #f29100 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.04em;
  font-variant-numeric: tabular-nums;
}
.countdown__label {
  margin-top: var(--space-2);
  font-size: 0.95rem;
  color: #fff;
  font-weight: 600;
  letter-spacing: .04em;
  text-transform: uppercase;
}
.countdown__deadline {
  margin-top: var(--space-2);
  font-size: 0.92rem;
  color: #ffd07a;
}
.countdown__cta {
  display: inline-block;
  margin-top: var(--space-4);
  padding: 10px 18px;
  border-radius: var(--radius);
  background: var(--c-cta);
  color: var(--c-cta-ink);
  font-weight: 700;
  text-decoration: none;
  font-size: 0.95rem;
}
.countdown__cta:hover { background: #ffae3d; color: var(--c-cta-ink); }
.countdown[data-state="closed"] .countdown__num,
.countdown[data-state="passed"] .countdown__num {
  background: linear-gradient(180deg, #cdd6e8 0%, #93a3c4 100%);
  -webkit-background-clip: text;
  background-clip: text;
}
.countdown[data-state="passed"] {
  opacity: 0.8;
}

.countdown--compact { padding: var(--space-4) var(--space-5); }
.countdown--compact .countdown__num { font-size: clamp(2.25rem, 5.5vw, 3.5rem); }
.countdown--compact .countdown__label { margin-top: 4px; font-size: 0.85rem; letter-spacing: .06em; }
.countdown--compact .countdown__deadline { font-size: 0.85rem; }

/* === STATS BAND ========================================= */
.stats {
  background: linear-gradient(180deg, #0b1e3b 0%, #1f3563 100%);
  color: #fff;
  padding-block: var(--space-7);
  position: relative;
  overflow: hidden;
}
.stats::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(60% 80% at 80% 50%, rgba(242,145,0,.18) 0%, transparent 60%);
  pointer-events: none;
}
.stats__grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(180px, 1fr));
  gap: var(--space-5);
  position: relative;
}
.stat {
  text-align: center;
}
.stat__num {
  font-size: clamp(2.25rem, 4.5vw, 3.25rem);
  font-weight: 800;
  background: linear-gradient(180deg, #ffd07a 0%, #f29100 100%);
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  letter-spacing: -0.02em;
  line-height: 1;
}
.stat__label {
  margin-top: var(--space-2);
  font-size: 0.92rem;
  color: #cdd6e8;
  text-transform: uppercase;
  letter-spacing: .12em;
  font-weight: 600;
}

/* === WHY ATTEND ========================================= */
.why {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: var(--space-5);
  margin-top: var(--space-6);
}
.why-card {
  position: relative;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: var(--space-6);
  overflow: hidden;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.why-card::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--c-accent) 0%, var(--c-cta) 100%);
}
.why-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px rgba(11,30,59,.10);
  border-color: var(--c-accent);
}
.why-card__icon {
  width: 48px; height: 48px;
  border-radius: 12px;
  background: var(--c-bg-band);
  color: var(--c-accent);
  display: grid;
  place-items: center;
  margin-bottom: var(--space-4);
}
.why-card__icon svg { width: 28px; height: 28px; }
.why-card h3 { margin: 0; font-size: 1.15rem; }
.why-card p { color: var(--c-mute); font-size: 0.95rem; margin-top: var(--space-2); }

/* === TRACK CARDS (rich) ================================= */
.tracks-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-5);
  margin-top: var(--space-6);
}
.track-card {
  position: relative;
  display: block;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: var(--space-6);
  overflow: hidden;
  text-decoration: none;
  color: inherit;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.track-card:hover h3 { color: var(--c-accent); }
.track-card:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px rgba(11,30,59,.12);
  border-color: var(--c-accent);
}
.track-card__icon {
  width: 56px; height: 56px;
  border-radius: 14px;
  background: linear-gradient(135deg, var(--c-bg-band) 0%, #fff 100%);
  border: 1px solid var(--c-line);
  color: var(--c-accent);
  display: grid;
  place-items: center;
  margin-bottom: var(--space-4);
}
.track-card__icon svg { width: 32px; height: 32px; }
.track-card h3 { margin: 0; font-size: 1.1rem; }
.track-card__alias {
  font-size: 0.78rem;
  color: var(--c-mute);
  text-transform: uppercase;
  letter-spacing: .12em;
  font-weight: 700;
  margin-bottom: var(--space-2);
}
.track-card p { color: var(--c-mute); font-size: 0.95rem; margin-top: var(--space-2); }

/* === SECTION DIVIDERS =================================== */
.section--curve-top {
  position: relative;
  margin-top: -1px;
}
.section--curve-top::before {
  content: "";
  position: absolute;
  top: 0; left: 0; right: 0;
  height: 60px;
  background:
    radial-gradient(150% 100% at 50% 0%, var(--c-bg-soft) 99%, transparent 100%);
  z-index: 0;
}
.section--curve-top > .container { position: relative; z-index: 1; }

/* === BUTTONS ============================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: 12px 20px;
  border-radius: var(--radius);
  text-decoration: none;
  font-weight: 600;
  border: 1px solid transparent;
  transition: transform .04s ease, background .15s ease, color .15s ease;
}
.btn:active { transform: translateY(1px); }
.btn--primary { background: var(--c-cta); color: var(--c-cta-ink); }
.btn--primary:hover { background: #d97e00; color: var(--c-cta-ink); }
.btn--ghost { background: transparent; color: var(--c-accent); border-color: var(--c-accent); }
.btn--ghost:hover { background: var(--c-accent); color: #fff; }

/* === CARDS ============================================== */
.grid {
  display: grid;
  gap: var(--space-5);
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}
.card {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: var(--space-5);
  box-shadow: var(--shadow);
}
.card h3 { margin: 0 0 var(--space-2) 0; font-size: 1.1rem; }
.card p { color: var(--c-mute); font-size: 0.95rem; }

.person {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: var(--space-5);
  text-align: center;
  transition: transform .18s ease, box-shadow .18s ease, border-color .18s ease;
}
.person:hover {
  transform: translateY(-3px);
  box-shadow: 0 18px 40px rgba(11,30,59,.10);
  border-color: var(--c-accent);
}
.person__photo {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  object-fit: cover;
  display: block;
  margin: 0 auto var(--space-4);
  border: 4px solid #fff;
  box-shadow: 0 0 0 2px var(--c-bg-band), 0 8px 24px rgba(11,30,59,.10);
  background: var(--c-bg-band);
}
.person__role {
  font-size: 0.78rem;
  color: var(--c-accent);
  text-transform: uppercase;
  letter-spacing: .10em;
  font-weight: 700;
}
.person__name { font-weight: 600; margin-top: 4px; line-height: 1.3; }
.person__aff  { color: var(--c-mute); font-size: 0.92rem; margin-top: 4px; }

/* === TABLES ============================================= */
.table-wrap { overflow-x: auto; -webkit-overflow-scrolling: touch; }
table.data {
  width: 100%;
  border-collapse: collapse;
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  overflow: hidden;
  font-size: 0.97rem;
}
table.data th, table.data td {
  text-align: left;
  padding: var(--space-3) var(--space-4);
  border-bottom: 1px solid var(--c-line);
  vertical-align: top;
}
table.data thead th {
  background: var(--c-bg-band);
  font-weight: 700;
  color: var(--c-ink);
}
table.data tbody tr:last-child td { border-bottom: 0; }
table.data td.num, table.data th.num { text-align: right; font-variant-numeric: tabular-nums; white-space: nowrap; }
table.data caption {
  caption-side: top;
  text-align: left;
  padding-bottom: var(--space-3);
  color: var(--c-mute);
  font-size: 0.92rem;
}
.note { color: var(--c-mute); font-size: 0.92rem; margin-top: var(--space-3); }

/* === SECTIONS / DETAILS ================================ */
.section-title { display: flex; align-items: baseline; gap: var(--space-3); }
.section-title small { color: var(--c-mute); font-weight: 500; font-size: 0.95rem; }
.lead { font-size: 1.1rem; color: var(--c-ink-2); max-width: 64ch; }

.track {
  background: #fff;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  padding: var(--space-5);
  margin-top: var(--space-4);
}
.track h3 { margin-top: 0; }
.track__alias { color: var(--c-mute); font-weight: 500; font-size: 0.95rem; }
.track ul { margin-top: var(--space-3); columns: 2; column-gap: var(--space-6); }
.track li { padding-left: 1em; text-indent: -1em; break-inside: avoid; padding-block: 2px; }
.track li::before { content: "› "; color: var(--c-accent); font-weight: 700; }
@media (max-width: 600px) { .track ul { columns: 1; } }

/* === FOOTER ============================================ */
.site-footer {
  background: var(--c-ink);
  color: #cdd6e8;
  padding-block: var(--space-7);
  margin-top: var(--space-8);
}
.site-footer a { color: #fff; }
.site-footer__cols {
  display: grid;
  gap: var(--space-6);
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
}
.site-footer h4 {
  color: #fff;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: .08em;
  margin-bottom: var(--space-3);
}
.site-footer ul li { margin-block: var(--space-2); }
.site-footer__legal {
  margin-top: var(--space-6);
  padding-top: var(--space-5);
  border-top: 1px solid #1f3563;
  font-size: 0.9rem;
  color: #93a3c4;
}

/* === UTILITIES ======================================== */
.muted { color: var(--c-mute); }
.center { text-align: center; }
.kbd {
  font-family: var(--font-mono);
  background: var(--c-bg-soft);
  border: 1px solid var(--c-line);
  padding: 2px 6px;
  border-radius: 4px;
  font-size: 0.92em;
}
.tag {
  display: inline-block;
  background: var(--c-bg-band);
  color: var(--c-accent);
  border-radius: 999px;
  padding: 2px 10px;
  font-size: 0.78rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: .06em;
}

.promo {
  background: linear-gradient(180deg, #fff7e6 0%, #fffaf0 100%);
  border: 1px solid #f0d49a;
  border-left: 4px solid var(--c-cta);
  border-radius: var(--radius);
  padding: var(--space-6);
  margin-top: var(--space-6);
  box-shadow: var(--shadow);
}
.promo h2 { margin-top: var(--space-3); }
.promo h3 {
  font-size: 1.05rem;
  margin-top: var(--space-5);
  color: var(--c-ink-2);
}
.promo ul { margin-top: var(--space-2); padding-left: 1.2em; list-style: disc; }
.promo ul ul { margin-top: var(--space-1); list-style: circle; }
.promo li { padding-block: 2px; }

.promo-banner {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  background: #fff7e6;
  border: 1px solid #f0d49a;
  border-radius: var(--radius);
  padding: var(--space-3) var(--space-4);
  margin-top: var(--space-5);
  font-size: 0.95rem;
}
.promo-banner .tag { background: var(--c-cta); color: #fff; }
.promo-banner a { font-weight: 600; }