/* ============================================================
   CODE FRONTIER 2026 — dark techno-minimal conference landing
   Portfolio demo · vanilla CSS · no external dependencies
   ============================================================ */

:root {
  --bg:        #05070a;
  --bg-2:      #0a0e14;
  --surface:   #0e131b;
  --surface-2: #131a24;
  --line:      rgba(255,255,255,.08);
  --line-2:    rgba(255,255,255,.14);
  --text:      #e8ecf2;
  --muted:     #8b94a3;
  --faint:     #5a6472;
  --accent:    #2ee6c8;
  --accent-2:  #38bdf8;
  --accent-soft: rgba(46,230,200,.12);
  --radius:    16px;
  --maxw:      1160px;
  --mono: ui-monospace, "SF Mono", "JetBrains Mono", "Cascadia Code", Menlo, Consolas, monospace;
  --sans: "Segoe UI", system-ui, -apple-system, Roboto, Helvetica, Arial, sans-serif;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

html { scroll-behavior: smooth; scroll-padding-top: 90px; }

body {
  font-family: var(--sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }
a { color: inherit; text-decoration: none; }
::selection { background: var(--accent); color: #04110f; }

.container { width: 100%; max-width: var(--maxw); margin-inline: auto; padding-inline: 24px; }

/* ---------- Scroll progress ---------- */
.scroll-progress {
  position: fixed; top: 0; left: 0; height: 2px; width: 0;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  z-index: 200; box-shadow: 0 0 12px var(--accent);
}

/* ---------- Header ---------- */
.site-header {
  position: fixed; top: 0; left: 0; right: 0; z-index: 100;
  display: flex; align-items: center; gap: 24px;
  padding: 18px 24px;
  max-width: var(--maxw); margin-inline: auto;
  transition: padding .3s ease;
}
.site-header::before {
  content: ""; position: absolute; inset: 0; z-index: -1;
  background: rgba(5,7,10,0); backdrop-filter: blur(0px);
  transition: background .3s ease, backdrop-filter .3s ease, border-color .3s ease;
  border-bottom: 1px solid transparent;
}
.site-header.is-stuck { padding: 12px 24px; }
.site-header.is-stuck::before {
  background: rgba(5,7,10,.78); backdrop-filter: blur(14px);
  border-bottom-color: var(--line);
}

.brand { display: inline-flex; align-items: center; gap: 10px; font-weight: 700; letter-spacing: .06em; font-size: 15px; }
.brand__mark { font-family: var(--mono); color: var(--accent); font-size: 15px; }
.brand__text { color: var(--text); }

.nav { display: flex; gap: 28px; margin-left: auto; font-size: 14px; color: var(--muted); }
.nav a { position: relative; transition: color .2s; padding: 4px 0; }
.nav a:hover { color: var(--text); }
.nav a::after {
  content: ""; position: absolute; left: 0; bottom: -2px; height: 1px; width: 0;
  background: var(--accent); transition: width .25s ease;
}
.nav a:hover::after { width: 100%; }

.nav-cta { margin-left: 4px; }

.burger { display: none; flex-direction: column; gap: 5px; background: none; border: 0; cursor: pointer; padding: 6px; }
.burger span { width: 24px; height: 2px; background: var(--text); border-radius: 2px; transition: .3s; }
.burger.is-open span:nth-child(1) { transform: translateY(7px) rotate(45deg); }
.burger.is-open span:nth-child(2) { opacity: 0; }
.burger.is-open span:nth-child(3) { transform: translateY(-7px) rotate(-45deg); }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex; align-items: center; justify-content: center;
  font-weight: 600; font-size: 15px; letter-spacing: .01em;
  padding: 14px 26px; border-radius: 999px; cursor: pointer;
  border: 1px solid transparent; transition: transform .15s ease, box-shadow .25s ease, background .25s, color .2s, border-color .2s;
  white-space: nowrap;
}
.btn:active { transform: translateY(1px) scale(.99); }
.btn--sm { padding: 9px 18px; font-size: 13px; }
.btn--full { width: 100%; }
.btn--primary { background: linear-gradient(120deg, var(--accent), var(--accent-2)); color: #04110f; box-shadow: 0 6px 24px -6px rgba(46,230,200,.5); }
.btn--primary:hover { transform: translateY(-2px); box-shadow: 0 12px 34px -8px rgba(46,230,200,.6); }
.btn--ghost { border-color: var(--line-2); color: var(--text); background: rgba(255,255,255,.02); }
.btn--ghost:hover { border-color: var(--accent); color: var(--accent); }

/* ---------- Hero ---------- */
.hero { position: relative; padding: 170px 0 60px; overflow: hidden; }
.hero__grid {
  position: absolute; inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 56px 56px;
  mask-image: radial-gradient(ellipse 90% 70% at 50% 20%, #000 40%, transparent 78%);
  -webkit-mask-image: radial-gradient(ellipse 90% 70% at 50% 20%, #000 40%, transparent 78%);
  opacity: .6;
}
.hero__glow {
  position: absolute; top: -20%; left: 50%; transform: translateX(-50%);
  width: 900px; height: 700px; pointer-events: none;
  background: radial-gradient(circle at 50% 40%, rgba(46,230,200,.16), transparent 60%),
              radial-gradient(circle at 60% 55%, rgba(56,189,248,.12), transparent 55%);
  filter: blur(10px);
}
.hero__inner { position: relative; z-index: 1; text-align: center; }

/* Floating decorative hero illustrations (custom inline SVG) */
.hero__deco { position: absolute; z-index: 0; pointer-events: none; filter: drop-shadow(0 20px 40px rgba(0,0,0,.5)); }
.hero__deco--l { left: 2.5%; top: 168px; width: 216px; animation: floatY 7s ease-in-out infinite; }
.hero__deco--r { right: 2.5%; top: 250px; width: 188px; animation: floatY 8.5s ease-in-out infinite reverse; }
@keyframes floatY { 0%,100% { transform: translateY(0) } 50% { transform: translateY(-16px) } }
@media (max-width: 1180px) { .hero__deco { display: none; } }

.eyebrow {
  display: inline-flex; align-items: center; gap: 9px;
  font-family: var(--mono); font-size: 13px; letter-spacing: .04em;
  color: var(--muted); padding: 7px 16px; border: 1px solid var(--line);
  border-radius: 999px; background: rgba(255,255,255,.02);
}
.eyebrow .dot { width: 7px; height: 7px; border-radius: 50%; background: var(--accent); box-shadow: 0 0 10px var(--accent); animation: pulse 2s infinite; }
@keyframes pulse { 0%,100% { opacity: 1; } 50% { opacity: .35; } }

.hero__title {
  font-size: clamp(2.6rem, 7vw, 5.4rem);
  line-height: 1.02; font-weight: 800; letter-spacing: -.03em;
  margin: 26px 0 22px;
}
.grad { background: linear-gradient(110deg, var(--accent), var(--accent-2) 60%, #a78bfa); -webkit-background-clip: text; background-clip: text; color: transparent; }
.hero__lead { max-width: 620px; margin: 0 auto; color: var(--muted); font-size: clamp(1rem, 1.4vw, 1.18rem); }
.hero__actions { display: flex; gap: 14px; justify-content: center; flex-wrap: wrap; margin-top: 34px; }

/* Countdown */
.countdown { display: flex; gap: 12px; justify-content: center; margin-top: 52px; flex-wrap: wrap; }
.countdown__cell {
  min-width: 92px; padding: 16px 10px; border-radius: 14px;
  background: linear-gradient(180deg, var(--surface), var(--bg-2));
  border: 1px solid var(--line); text-align: center;
}
.countdown__cell b { display: block; font-family: var(--mono); font-size: 2.1rem; font-weight: 600; color: var(--text); letter-spacing: .02em; }
.countdown__cell span { font-size: 12px; color: var(--faint); text-transform: uppercase; letter-spacing: .14em; }

/* Hero stats */
.hero__stats { display: grid; grid-template-columns: repeat(4, 1fr); gap: 16px; margin-top: 72px; }
.stat { text-align: center; padding: 22px 12px; border-radius: 14px; border: 1px solid var(--line); background: rgba(255,255,255,.015); }
.stat b { display: block; font-size: clamp(1.8rem, 3vw, 2.6rem); font-weight: 800; color: var(--accent); letter-spacing: -.02em; }
.stat span { color: var(--muted); font-size: 13px; text-transform: uppercase; letter-spacing: .1em; }

/* ---------- Marquee ---------- */
.marquee { overflow: hidden; border-block: 1px solid var(--line); padding: 18px 0; margin-top: 60px; background: var(--bg-2); }
.marquee__track { display: flex; gap: 26px; width: max-content; animation: scroll-x 32s linear infinite; }
.marquee__track span { font-family: var(--mono); font-size: 15px; color: var(--faint); letter-spacing: .05em; }
.marquee__track span:not(:nth-child(even)) { color: var(--muted); }
@keyframes scroll-x { to { transform: translateX(-50%); } }

/* ---------- Sections ---------- */
.section { padding: 100px 0; position: relative; }
.section--alt { background: var(--bg-2); border-block: 1px solid var(--line); }
.section-eyebrow { font-family: var(--mono); font-size: 13px; color: var(--accent); letter-spacing: .1em; text-transform: uppercase; margin-bottom: 14px; }
.section-title { font-size: clamp(1.8rem, 4vw, 3rem); font-weight: 800; letter-spacing: -.025em; line-height: 1.08; }
.section-head { display: flex; align-items: flex-end; justify-content: space-between; gap: 24px; margin-bottom: 54px; flex-wrap: wrap; }
.section-note { color: var(--faint); font-size: 14px; font-family: var(--mono); }

/* About */
.about__grid { display: grid; grid-template-columns: 1fr 1.1fr; gap: 60px; align-items: start; }
.about__body p { color: var(--muted); margin-bottom: 18px; font-size: 1.05rem; }
.feature-list { list-style: none; margin-top: 26px; display: grid; gap: 12px; }
.feature-list li { display: flex; gap: 12px; align-items: baseline; color: var(--text); }
.feature-list i { color: var(--accent); font-style: normal; font-family: var(--mono); }

/* Speakers */
.speakers-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.speaker {
  padding: 26px; border-radius: var(--radius); border: 1px solid var(--line);
  background: linear-gradient(180deg, var(--surface), var(--bg-2));
  transition: transform .25s ease, border-color .25s ease, box-shadow .25s ease;
}
.speaker:hover { transform: translateY(-4px); border-color: var(--line-2); box-shadow: 0 20px 40px -24px rgba(0,0,0,.8); }
.speaker__avatar {
  width: 60px; height: 60px; border-radius: 14px; margin-bottom: 18px;
  display: grid; place-items: center; font-family: var(--mono); font-weight: 600; font-size: 18px; color: #04110f;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
}
.speaker__avatar::before { content: attr(data-initials); }
.speaker h3 { font-size: 1.15rem; font-weight: 700; margin-bottom: 4px; }
.speaker__role { color: var(--accent); font-size: 13px; font-family: var(--mono); margin-bottom: 14px; }
.speaker__topic { color: var(--muted); font-size: .95rem; }

/* Schedule */
.day-switch { display: inline-flex; padding: 5px; gap: 4px; border: 1px solid var(--line); border-radius: 999px; background: var(--surface); }
.day-switch__btn { border: 0; background: none; color: var(--muted); padding: 8px 18px; border-radius: 999px; cursor: pointer; font-size: 14px; font-weight: 600; transition: .2s; }
.day-switch__btn.is-active { background: var(--accent-soft); color: var(--accent); }

.timeline { display: grid; gap: 2px; }
.timeline.is-hidden { display: none; }
.tl-row { display: grid; grid-template-columns: 96px 1fr; gap: 24px; padding: 20px; border-radius: 12px; border: 1px solid transparent; transition: .2s; }
.tl-row:hover { background: var(--surface); border-color: var(--line); }
.tl-time { font-family: var(--mono); color: var(--accent); font-size: 15px; padding-top: 2px; }
.tl-body h4 { font-size: 1.08rem; font-weight: 700; margin-bottom: 3px; }
.tl-body p { color: var(--muted); font-size: .94rem; }
.tl-body--break h4 { color: var(--muted); }
.tl-body--party h4 { color: #a78bfa; }

/* Tickets */
.tickets-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; align-items: stretch; }
.ticket {
  position: relative; padding: 34px 28px; border-radius: var(--radius); border: 1px solid var(--line);
  background: var(--surface); display: flex; flex-direction: column; transition: transform .25s, border-color .25s;
}
.ticket:hover { transform: translateY(-4px); border-color: var(--line-2); }
.ticket--featured { border-color: var(--accent); background: linear-gradient(180deg, rgba(46,230,200,.06), var(--surface)); box-shadow: 0 24px 60px -30px rgba(46,230,200,.5); }
.ticket__badge { position: absolute; top: 18px; right: 18px; font-size: 11px; font-family: var(--mono); text-transform: uppercase; letter-spacing: .1em; color: #04110f; background: var(--accent); padding: 4px 12px; border-radius: 999px; }
.ticket__name { font-family: var(--mono); color: var(--muted); text-transform: uppercase; letter-spacing: .12em; font-size: 13px; }
.ticket__price { font-size: 2.6rem; font-weight: 800; letter-spacing: -.03em; margin: 10px 0 22px; }
.ticket__price span { font-size: 1.3rem; color: var(--muted); vertical-align: super; margin-right: 4px; }
.ticket ul { list-style: none; display: grid; gap: 12px; margin-bottom: 28px; flex-grow: 1; }
.ticket li { color: var(--muted); font-size: .95rem; padding-left: 26px; position: relative; }
.ticket li::before { content: "✓"; position: absolute; left: 0; color: var(--accent); font-weight: 700; }
.tickets-note { text-align: center; margin-top: 24px; color: var(--accent); font-family: var(--mono); font-size: 14px; min-height: 20px; }

/* FAQ */
.faq__wrap { display: grid; grid-template-columns: .8fr 1.4fr; gap: 60px; align-items: start; }
.accordion { display: grid; gap: 12px; }
.acc-item { border: 1px solid var(--line); border-radius: 12px; background: var(--surface); overflow: hidden; transition: border-color .2s; }
.acc-item.is-open { border-color: var(--line-2); }
.acc-head { width: 100%; display: flex; align-items: center; justify-content: space-between; gap: 16px; padding: 20px 22px; background: none; border: 0; cursor: pointer; color: var(--text); font-size: 1.05rem; font-weight: 600; text-align: left; font-family: inherit; }
.acc-head i { position: relative; width: 16px; height: 16px; flex-shrink: 0; }
.acc-head i::before, .acc-head i::after { content: ""; position: absolute; background: var(--accent); border-radius: 2px; transition: transform .25s ease; }
.acc-head i::before { top: 7px; left: 0; width: 16px; height: 2px; }
.acc-head i::after { top: 0; left: 7px; width: 2px; height: 16px; }
.acc-item.is-open .acc-head i::after { transform: scaleY(0); }
.acc-body { max-height: 0; overflow: hidden; transition: max-height .3s ease; }
.acc-body p { padding: 0 22px 22px; color: var(--muted); }

/* CTA */
.cta { padding: 90px 0; }
.cta__inner {
  text-align: center; padding: 70px 40px; border-radius: 28px;
  border: 1px solid var(--line); position: relative; overflow: hidden;
  background:
    radial-gradient(circle at 50% 0%, rgba(46,230,200,.14), transparent 60%),
    linear-gradient(180deg, var(--surface), var(--bg-2));
}
.cta__inner h2 { font-size: clamp(1.7rem, 3.6vw, 2.8rem); font-weight: 800; letter-spacing: -.02em; margin-bottom: 14px; }
.cta__inner p { color: var(--muted); margin-bottom: 30px; }

/* Footer */
.footer { border-top: 1px solid var(--line); padding-top: 60px; background: var(--bg-2); }
.footer__grid { display: grid; grid-template-columns: 1.5fr 1fr auto; gap: 40px; padding-bottom: 44px; }
.brand--footer { margin-bottom: 16px; }
.footer__loc { color: var(--faint); font-size: 14px; line-height: 1.7; }
.footer__nav { display: grid; gap: 12px; }
.footer__nav a { color: var(--muted); font-size: 14px; transition: color .2s; }
.footer__nav a:hover { color: var(--accent); }
.footer__social { display: flex; gap: 10px; align-items: flex-start; }
.soc { width: 42px; height: 42px; display: grid; place-items: center; border: 1px solid var(--line); border-radius: 12px; font-family: var(--mono); font-size: 13px; color: var(--muted); transition: .2s; }
.soc:hover { border-color: var(--accent); color: var(--accent); transform: translateY(-2px); }
.footer__bottom { display: flex; justify-content: space-between; gap: 16px; flex-wrap: wrap; padding: 24px 0; border-top: 1px solid var(--line); color: var(--faint); font-size: 13px; font-family: var(--mono); }

/* ---------- Reveal animation ---------- */
.reveal { opacity: 0; transform: translateY(26px); transition: opacity .6s ease, transform .6s ease; }
.reveal.is-visible { opacity: 1; transform: none; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .nav, .nav-cta { display: none; }
  .burger { display: flex; }
  .site-header { justify-content: space-between; }
  .nav.is-open {
    display: flex; flex-direction: column; gap: 4px;
    position: absolute; top: 100%; left: 0; right: 0;
    background: rgba(5,7,10,.96); backdrop-filter: blur(14px);
    padding: 16px 24px 24px; border-bottom: 1px solid var(--line);
  }
  .nav.is-open a { padding: 12px 0; font-size: 16px; border-bottom: 1px solid var(--line); }
  .about__grid, .faq__wrap { grid-template-columns: 1fr; gap: 30px; }
  .speakers-grid, .tickets-grid { grid-template-columns: 1fr 1fr; }
  .footer__grid { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 620px) {
  .hero { padding-top: 130px; }
  .hero__stats { grid-template-columns: 1fr 1fr; }
  .speakers-grid, .tickets-grid { grid-template-columns: 1fr; }
  .countdown__cell { min-width: 70px; }
  .countdown__cell b { font-size: 1.6rem; }
  .tl-row { grid-template-columns: 68px 1fr; gap: 14px; padding: 16px 12px; }
  .footer__grid { grid-template-columns: 1fr; }
  .section { padding: 70px 0; }
  .cta__inner { padding: 46px 22px; }
}

@media (prefers-reduced-motion: reduce) {
  * { animation: none !important; scroll-behavior: auto; }
  .reveal { opacity: 1; transform: none; transition: none; }
}