:root {
  --ink: #16213a;
  --ink-soft: #46516b;
  --muted: #6b7489;
  --bg: #fbfaf7;
  --tint: #f2efe8;
  --card: #ffffff;
  --line: #e3dfd5;
  --red: #e2231a; /* Swiss red */
  --red-dark: #b81b14;
  --yellow: #ffd23f;
  --radius: 14px;
  --shadow: 0 1px 2px rgba(22, 33, 58, 0.06), 0 8px 24px rgba(22, 33, 58, 0.06);
  --font: "Inter", system-ui, -apple-system, "Segoe UI", Roboto, sans-serif;
  --display: "Space Grotesk", var(--font);
}

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  margin: 0;
  font-family: var(--font);
  font-size: 17px;
  line-height: 1.6;
  color: var(--ink);
  background: var(--bg);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4 {
  font-family: var(--display);
  line-height: 1.15;
  margin: 0 0 0.5em;
  letter-spacing: -0.01em;
}
h1 { font-size: clamp(2.6rem, 7vw, 4.75rem); letter-spacing: -0.03em; }
h2 { font-size: clamp(1.9rem, 4vw, 2.75rem); letter-spacing: -0.02em; }
h3 { font-size: 1.2rem; }
p { margin: 0 0 1em; }
a { color: inherit; }

.container {
  width: 100%;
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}
.narrow { max-width: 780px; }

.visually-hidden {
  position: absolute !important;
  width: 1px !important; height: 1px !important;
  padding: 0 !important;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ---------- Buttons ---------- */
.btn {
  display: inline-block;
  padding: 0.85em 1.5em;
  border: 2px solid var(--red);
  border-radius: 999px;
  background: var(--red);
  color: #fff;
  font: 600 1rem/1.2 var(--font);
  text-decoration: none;
  cursor: pointer;
  transition: background 0.15s, border-color 0.15s, transform 0.15s;
}
.btn:hover { background: var(--red-dark); border-color: var(--red-dark); transform: translateY(-1px); }
.btn:focus-visible { outline: 3px solid var(--yellow); outline-offset: 2px; }
.btn:disabled { opacity: 0.6; cursor: wait; transform: none; }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.btn-ghost:hover { background: var(--ink); border-color: var(--ink); color: #fff; }
.btn-small { padding: 0.55em 1.1em; font-size: 0.95rem; }
.btn-block { width: 100%; }

/* ---------- Header ---------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 10;
  background: rgba(251, 250, 247, 0.9);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--line);
}
.nav {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 68px;
}
.logo {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font: 700 1.25rem var(--display);
  text-decoration: none;
  letter-spacing: -0.02em;
}
.logo-mark {
  display: grid;
  place-items: center;
  width: 30px; height: 30px;
  border-radius: 7px;
  background: var(--red);
  color: #fff;
  font-size: 1.5rem;
  line-height: 1;
}
.logo .accent { color: var(--red); }
.logo-tld { color: var(--muted); font-weight: 500; }

.nav-links { display: flex; align-items: center; gap: 28px; }
.nav-links a:not(.btn) {
  text-decoration: none;
  font-weight: 500;
  color: var(--ink-soft);
}
.nav-links a:not(.btn):hover { color: var(--red); }

.nav-toggle {
  display: none;
  background: none;
  border: 0;
  padding: 8px;
  cursor: pointer;
}
.nav-toggle span {
  display: block;
  width: 24px; height: 2px;
  margin: 5px 0;
  background: var(--ink);
  border-radius: 2px;
}

/* ---------- Hero ---------- */
.hero {
  position: relative;
  overflow: hidden;
  padding: 96px 0 80px;
}
.hero::before {
  /* subtle Swiss-cross pattern */
  content: "";
  position: absolute;
  inset: 0;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='48' height='48'%3E%3Cpath d='M22 18h4v4h4v4h-4v4h-4v-4h-4v-4h4z' fill='%23e2231a' fill-opacity='0.07'/%3E%3C/svg%3E");
  mask-image: linear-gradient(to left, #000 20%, transparent 75%);
  -webkit-mask-image: linear-gradient(to left, #000 20%, transparent 75%);
  pointer-events: none;
}
.hero-inner { position: relative; }
.highlight {
  background: linear-gradient(transparent 62%, var(--yellow) 62%, var(--yellow) 92%, transparent 92%);
}
.lead {
  max-width: 620px;
  font-size: 1.2rem;
  color: var(--ink-soft);
  margin: 1.25em 0 2em;
}
.hero-actions { display: flex; flex-wrap: wrap; gap: 14px; }
.hero-event {
  display: inline-flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 10px;
  margin-top: 48px;
  padding: 12px 18px;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow);
  font-size: 0.98rem;
}
.hero-event .dot { color: var(--muted); }
.pill {
  display: inline-block;
  padding: 0.2em 0.7em;
  border-radius: 999px;
  background: var(--red);
  color: #fff;
  font-size: 0.8rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.04em;
}

.eyebrow {
  margin-bottom: 0.9em;
  color: var(--red);
  font-size: 0.85rem;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.1em;
}
.eyebrow-light { color: var(--yellow); }

/* ---------- Sections ---------- */
.section { padding: 96px 0; }
.section-tinted { background: var(--tint); }
.section-dark { background: var(--ink); color: #fff; }
.section-lead { max-width: 640px; color: var(--ink-soft); font-size: 1.1rem; }

.two-col {
  display: grid;
  grid-template-columns: 1fr 1.4fr;
  gap: 48px;
}
.prose p { color: var(--ink-soft); font-size: 1.08rem; }
.prose strong { color: var(--ink); }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
}
.card p { color: var(--ink-soft); margin: 0; }
.card-icon {
  display: grid;
  place-items: center;
  width: 48px; height: 48px;
  margin-bottom: 18px;
  border-radius: 12px;
  background: #fde8e6;
}
.card-icon svg { width: 26px; height: 26px; fill: var(--red); }

.values, .roles {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}
.values { margin-top: 64px; }
.roles { margin-top: 40px; }
.roles .card { border-top: 4px solid var(--red); }

/* Steps */
.steps {
  list-style: none;
  padding: 0;
  margin: 40px 0 0;
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 24px;
  counter-reset: none;
}
.steps li { position: relative; }
.steps p { color: var(--ink-soft); }
.step-num {
  display: grid;
  place-items: center;
  width: 44px; height: 44px;
  margin-bottom: 18px;
  border-radius: 50%;
  background: var(--ink);
  color: #fff;
  font: 700 1.1rem var(--display);
}

/* Tags */
.tags {
  list-style: none;
  padding: 0;
  margin: 32px 0 0;
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.tags li {
  padding: 0.6em 1.2em;
  border: 1.5px solid var(--ink);
  border-radius: 999px;
  font-weight: 500;
}
.tags li:last-child { background: var(--yellow); border-color: var(--yellow); }

/* ---------- Next hackathon ---------- */
.event-head {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: flex-end;
  gap: 24px;
  margin-bottom: 48px;
}
.event-head h2 { margin-bottom: 0.2em; }
.event-theme { color: #c4cad8; font-size: 1.15rem; margin: 0; }

.countdown { display: flex; gap: 12px; }
.countdown[hidden] { display: none; }
.countdown div {
  min-width: 84px;
  padding: 14px 10px;
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.12);
  text-align: center;
}
.countdown span { display: block; font: 700 2rem/1 var(--display); }
.countdown small { color: #c4cad8; font-size: 0.8rem; text-transform: uppercase; letter-spacing: 0.08em; }

.event-grid {
  display: grid;
  grid-template-columns: 1fr 1.2fr;
  gap: 48px;
}
.event-facts dl { margin: 0 0 32px; }
.event-facts dl > div {
  display: grid;
  grid-template-columns: 160px 1fr;
  gap: 16px;
  padding: 16px 0;
  border-bottom: 1px solid rgba(255, 255, 255, 0.12);
}
.event-facts dt { color: #c4cad8; font-weight: 500; }
.event-facts dd { margin: 0; font-weight: 600; }

.schedule {
  padding: 32px;
  border-radius: var(--radius);
  background: rgba(255, 255, 255, 0.05);
  border: 1px solid rgba(255, 255, 255, 0.12);
}
.schedule-day + .schedule-day { margin-top: 24px; }
.schedule h4 { color: var(--yellow); font-size: 1rem; margin-bottom: 0.6em; }
.schedule ul { list-style: none; margin: 0; padding: 0; }
.schedule li { display: flex; gap: 16px; padding: 6px 0; }
.schedule time { flex: 0 0 52px; color: #c4cad8; font-variant-numeric: tabular-nums; }

/* ---------- Sign-up form ---------- */
.signup {
  display: grid;
  grid-template-columns: 1fr 1.3fr;
  gap: 56px;
  align-items: start;
}
.signup-intro p { color: var(--ink-soft); }
.signup-intro .muted { color: var(--muted); font-size: 0.95rem; }

.form {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 20px;
  padding: 36px;
  box-shadow: var(--shadow);
}
.field { margin: 0 0 20px; padding: 0; border: 0; min-width: 0; }
.field-row { display: grid; grid-template-columns: 1fr 1fr; gap: 16px; }
.field label, .field legend {
  display: block;
  margin-bottom: 6px;
  font-weight: 600;
  font-size: 0.95rem;
}
.req { color: var(--red); }

input[type="text"], input[type="email"], select, textarea {
  width: 100%;
  padding: 0.75em 0.9em;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  color: var(--ink);
  font: inherit;
  font-size: 1rem;
  transition: border-color 0.15s, box-shadow 0.15s;
}
textarea { resize: vertical; }
input:focus, select:focus, textarea:focus {
  outline: none;
  border-color: var(--ink);
  box-shadow: 0 0 0 3px rgba(22, 33, 58, 0.12);
  background: #fff;
}
[aria-invalid="true"] { border-color: var(--red) !important; }

.choice-grid { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.choice { margin: 0 !important; cursor: pointer; }
.choice input { position: absolute; opacity: 0; }
.choice span {
  display: block;
  padding: 0.7em 0.9em;
  border: 1.5px solid var(--line);
  border-radius: 10px;
  font-weight: 500;
  text-align: center;
  transition: all 0.15s;
}
.choice:hover span { border-color: var(--ink-soft); }
.choice input:checked + span { border-color: var(--red); background: #fde8e6; color: var(--red-dark); }
.choice input:focus-visible + span { outline: 3px solid var(--yellow); outline-offset: 1px; }

.checkbox label {
  display: flex;
  gap: 10px;
  align-items: flex-start;
  font-weight: 400;
  color: var(--ink-soft);
}
.checkbox input { margin-top: 0.3em; width: 18px; height: 18px; accent-color: var(--red); flex: 0 0 auto; }

.error { display: none; margin: 6px 0 0; color: var(--red-dark); font-size: 0.88rem; }
.error.visible { display: block; }

.form-status { margin: 16px 0 0; font-weight: 500; }
.form-status:empty { display: none; }
.form-status.success { padding: 12px 16px; border-radius: 10px; background: #e6f4ea; color: #1e6b3a; }
.form-status.fail { padding: 12px 16px; border-radius: 10px; background: #fde8e6; color: var(--red-dark); }

/* ---------- FAQ ---------- */
.faq { margin-top: 32px; }
.faq details {
  border-bottom: 1px solid var(--line);
  padding: 4px 0;
}
.faq summary {
  position: relative;
  padding: 18px 40px 18px 0;
  font: 600 1.1rem var(--display);
  cursor: pointer;
  list-style: none;
}
.faq summary::-webkit-details-marker { display: none; }
.faq summary::after {
  content: "+";
  position: absolute;
  right: 6px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--red);
  font-size: 1.6rem;
  transition: transform 0.2s;
}
.faq details[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.faq details p { color: var(--ink-soft); padding-right: 40px; }

/* ---------- Footer ---------- */
.site-footer { background: var(--ink); color: #c4cad8; padding: 64px 0 24px; }
.footer-inner {
  display: grid;
  grid-template-columns: 2fr 1fr 1fr;
  gap: 40px;
}
.site-footer h3 { color: #fff; font-size: 1rem; }
.site-footer a { color: #fff; text-decoration: none; }
.site-footer a:hover { color: var(--yellow); }
.logo-light { color: #fff; margin-bottom: 16px; }
.logo-light .logo-tld { color: #8d96ab; }
.footer-bottom {
  margin-top: 48px;
  padding-top: 24px;
  border-top: 1px solid rgba(255, 255, 255, 0.1);
  font-size: 0.9rem;
}
.footer-bottom p { margin: 0; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  .steps { grid-template-columns: repeat(2, 1fr); }
  .event-grid, .signup, .two-col { grid-template-columns: 1fr; gap: 32px; }
}

@media (max-width: 760px) {
  body { font-size: 16px; }
  .container { padding: 0 20px; }
  .section { padding: 72px 0; }
  .hero { padding: 64px 0 56px; }

  .nav-toggle { display: block; }
  .nav-links {
    display: none;
    position: absolute;
    top: 68px; left: 0; right: 0;
    flex-direction: column;
    align-items: stretch;
    gap: 0;
    padding: 8px 20px 20px;
    background: var(--bg);
    border-bottom: 1px solid var(--line);
    box-shadow: var(--shadow);
  }
  .nav-links.open { display: flex; }
  .nav-links a:not(.btn) { padding: 12px 0; border-bottom: 1px solid var(--line); }
  .nav-links .btn { margin-top: 16px; text-align: center; }

  .values, .roles, .steps { grid-template-columns: 1fr; }
  .field-row { grid-template-columns: 1fr; gap: 0; }
  .form { padding: 24px; }
  .event-facts dl > div { grid-template-columns: 1fr; gap: 2px; }
  .countdown div { min-width: 72px; }
  .footer-inner { grid-template-columns: 1fr; gap: 24px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}