/* ============================================================
   Rapid Build Hackathon — Viksit UP
   Theme: refined editorial w/ warm saffron + deep emerald
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=Fraunces:opsz,wght@9..144,300;9..144,400;9..144,500;9..144,600;9..144,700&family=DM+Sans:opsz,wght@9..40,300;9..40,400;9..40,500;9..40,600;9..40,700&family=JetBrains+Mono:wght@400;500&display=swap');

:root {
  --ink: #16201B;
  --ink-soft: #2E3A33;
  --muted: #5C6A61;
  --line: #E3DED2;
  --line-strong: #CFC8B7;

  --paper: #F7F3EA;
  --paper-2: #F1ECDE;
  --surface: #FFFFFF;

  --emerald: #0E5E3E;
  --emerald-soft: #E3F0E7;
  --emerald-ink: #07442A;

  --saffron: #E07A1F;
  --saffron-soft: #FCEBD4;
  --saffron-ink: #8A3F00;

  --indigo: #1E3A5F;
  --indigo-soft: #E5EBF3;

  --radius-s: 8px;
  --radius-m: 14px;
  --radius-l: 22px;

  --shadow-soft: 0 1px 0 rgba(22,32,27,0.04), 0 10px 30px -18px rgba(22,32,27,0.18);
  --shadow-card: 0 1px 0 rgba(22,32,27,0.04), 0 20px 50px -28px rgba(22,32,27,0.25);

  --font-display: 'Fraunces', ui-serif, Georgia, serif;
  --font-body: 'DM Sans', ui-sans-serif, system-ui, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;
}

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

body {
  font-family: var(--font-body);
  color: var(--ink);
  background: var(--paper);
  -webkit-font-smoothing: antialiased;
  font-size: 16px;
  line-height: 1.55;
  min-height: 100vh;
  display: flex;
  flex-direction: column;

  /* subtle paper grain + warm vignette */
  background-image:
    radial-gradient(1200px 600px at 85% -10%, rgba(224,122,31,0.08), transparent 60%),
    radial-gradient(1000px 500px at -10% 110%, rgba(14,94,62,0.07), transparent 60%);
  background-attachment: fixed;
}

/* ---------- Navigation / top bar ---------- */
.topbar {
  padding: 22px 48px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  border-bottom: 1px solid var(--line);
  background: rgba(247,243,234,0.7);
  backdrop-filter: saturate(1.1) blur(8px);
  position: sticky;
  top: 0;
  z-index: 40;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  text-decoration: none;
  color: var(--ink);
}

.brand-mark {
  width: 34px; height: 34px; border-radius: 10px;
  background: linear-gradient(135deg, var(--emerald) 0%, var(--emerald-ink) 100%);
  display: grid; place-items: center;
  color: #fff; font-family: var(--font-display); font-weight: 600;
  box-shadow: inset 0 0 0 1px rgba(255,255,255,0.15), 0 6px 16px -8px rgba(14,94,62,0.6);
}
.brand-mark::before {
  content: '';
  width: 14px; height: 14px;
  background:
    linear-gradient(var(--saffron), var(--saffron)) center/2px 14px no-repeat,
    linear-gradient(var(--saffron), var(--saffron)) center/14px 2px no-repeat;
  transform: rotate(45deg);
  opacity: 0.95;
}

.brand-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 18px;
  letter-spacing: -0.01em;
}
.brand-title em {
  font-style: italic;
  color: var(--emerald);
  font-weight: 500;
}
.brand-tag {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  color: var(--muted);
  margin-top: 2px;
}

.nav-links {
  display: flex;
  gap: 8px;
  align-items: center;
}
.nav-link {
  font-size: 13px;
  text-decoration: none;
  color: var(--ink-soft);
  padding: 8px 14px;
  border-radius: 999px;
  border: 1px solid transparent;
  transition: all 0.2s ease;
}
.nav-link:hover { border-color: var(--line-strong); background: var(--surface); }
.nav-link.is-active {
  background: var(--ink);
  color: var(--paper);
  border-color: var(--ink);
}

/* ---------- Generic layout ---------- */
main {
  flex: 1;
  padding: 56px 48px 88px;
  max-width: 1280px;
  width: 100%;
  margin: 0 auto;
}

.page-kicker {
  display: inline-flex;
  gap: 10px;
  align-items: center;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--muted);
  margin-bottom: 16px;
}
.page-kicker::before {
  content: '';
  width: 28px; height: 1px; background: var(--line-strong);
}

.page-title {
  font-family: var(--font-display);
  font-weight: 400;
  font-size: clamp(42px, 5.4vw, 72px);
  line-height: 1.02;
  letter-spacing: -0.02em;
  margin: 0 0 12px;
}
.page-title em {
  font-style: italic;
  color: var(--emerald);
  font-weight: 400;
}
.page-title .sa {
  color: var(--saffron);
  font-style: italic;
}

.page-lead {
  font-size: 18px;
  color: var(--ink-soft);
  max-width: 680px;
  line-height: 1.55;
}

.rule {
  height: 1px;
  background: var(--line);
  margin: 48px 0 40px;
}

/* ---------- Landing / track cards ---------- */
.track-intro {
  display: flex;
  justify-content: space-between;
  align-items: flex-end;
  flex-wrap: wrap;
  gap: 18px;
  margin-bottom: 28px;
}
.track-intro h2 {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 26px;
  letter-spacing: -0.01em;
  margin: 0;
}
.track-intro .meta {
  font-size: 12px;
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--muted);
  font-family: var(--font-mono);
}

.tracks {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 26px;
}

.track-card {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-l);
  padding: 34px 34px 30px;
  text-decoration: none;
  color: inherit;
  transition: transform 0.35s cubic-bezier(.2,.8,.2,1), box-shadow 0.35s ease, border-color 0.2s;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  min-height: 320px;
}
.track-card::after {
  content: '';
  position: absolute;
  inset: 0;
  border-radius: inherit;
  pointer-events: none;
  background:
    radial-gradient(400px 160px at 100% 0%, var(--accent-soft, transparent), transparent 60%);
  opacity: 0.9;
}
.track-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-card);
  border-color: var(--line-strong);
}

.track-card[data-accent="emerald"] { --accent: var(--emerald); --accent-soft: var(--emerald-soft); }
.track-card[data-accent="saffron"] { --accent: var(--saffron); --accent-soft: var(--saffron-soft); }

.track-num {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.15em;
}
.track-icon {
  width: 46px; height: 46px;
  border-radius: 12px;
  background: var(--accent-soft);
  color: var(--accent);
  display: grid; place-items: center;
  margin: 18px 0 22px;
  position: relative;
  z-index: 1;
}
.track-icon svg { width: 22px; height: 22px; }

.track-card h3 {
  font-family: var(--font-display);
  font-size: 30px;
  font-weight: 500;
  letter-spacing: -0.02em;
  margin: 0 0 10px;
  display: flex;
  align-items: center;
  gap: 10px;
  position: relative;
  z-index: 1;
}
.track-card h3 .arrow {
  transition: transform 0.3s ease;
  color: var(--accent);
}
.track-card:hover h3 .arrow { transform: translateX(6px); }

.track-card p {
  color: var(--ink-soft);
  font-size: 15px;
  line-height: 1.6;
  margin: 0 0 22px;
  max-width: 46ch;
  position: relative; z-index: 1;
}

.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: auto; position: relative; z-index: 1; }
.chip {
  font-size: 12px;
  font-family: var(--font-mono);
  padding: 5px 10px;
  border-radius: 999px;
  background: var(--paper-2);
  border: 1px solid var(--line);
  color: var(--ink-soft);
}

/* ---------- Theme sections on challenges page ---------- */
.theme {
  margin-bottom: 56px;
}
.theme-head {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 22px;
  padding-bottom: 14px;
  border-bottom: 1px dashed var(--line-strong);
}
.theme-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 30px;
  letter-spacing: -0.01em;
  margin: 0;
  display: flex;
  align-items: baseline;
  gap: 12px;
}
.theme-title .pill {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: 4px 9px;
  border-radius: 999px;
  background: var(--accent-soft, var(--emerald-soft));
  color: var(--accent, var(--emerald-ink));
  border: 1px solid transparent;
  position: relative;
  top: -4px;
}
.theme-meaning {
  font-family: var(--font-display);
  font-style: italic;
  color: var(--muted);
  font-size: 16px;
}

.theme[data-accent="emerald"] { --accent: var(--emerald-ink); --accent-soft: var(--emerald-soft); }
.theme[data-accent="saffron"] { --accent: var(--saffron-ink); --accent-soft: var(--saffron-soft); }
.theme[data-accent="indigo"]  { --accent: var(--indigo); --accent-soft: var(--indigo-soft); }

.challenge-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
  /* Each card sizes to its own content — only the clicked card grows. */
  align-items: start;
}

/* ---------- Challenge card (collapsible <details>) ---------- */
.challenge-card {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  transition: box-shadow 0.25s ease, border-color 0.2s;
  position: relative;
  overflow: hidden;
}
.challenge-card::before {
  content: '';
  position: absolute;
  left: 0; top: 0; bottom: 0;
  width: 3px;
  background: var(--accent, var(--emerald));
  opacity: 0.85;
  z-index: 1;
}
.challenge-card:hover {
  box-shadow: var(--shadow-soft);
  border-color: var(--line-strong);
}
.challenge-card[open] {
  box-shadow: var(--shadow-soft);
  border-color: var(--line-strong);
}

/* Summary — clickable title row */
.challenge-card > summary {
  list-style: none;
  cursor: pointer;
  padding: 22px 24px 20px;
  display: flex;
  flex-direction: column;
  gap: 12px;
  transition: background 0.2s ease;
  user-select: none;
}
.challenge-card > summary::-webkit-details-marker { display: none; }
.challenge-card > summary::marker { content: ''; }
.challenge-card > summary:hover { background: rgba(14,94,62,0.025); }
.challenge-card > summary:focus-visible {
  outline: 2px solid var(--emerald);
  outline-offset: -2px;
  border-radius: var(--radius-m);
}

.summary-row {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 14px;
}

.chevron {
  flex-shrink: 0;
  width: 30px;
  height: 30px;
  border-radius: 999px;
  background: var(--paper-2);
  border: 1px solid var(--line);
  color: var(--ink-soft);
  display: grid;
  place-items: center;
  transition: transform 0.3s cubic-bezier(.2,.8,.2,1), background 0.2s, color 0.2s;
  margin-top: 2px;
}
.chevron svg { width: 14px; height: 14px; }
.challenge-card[open] .chevron {
  transform: rotate(180deg);
  background: var(--emerald);
  color: #fff;
  border-color: var(--emerald);
}

/* Expanded body */
.challenge-body {
  padding: 0 24px 22px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  animation: card-reveal 0.35s cubic-bezier(.2,.8,.2,1);
}
@keyframes card-reveal {
  from { opacity: 0; transform: translateY(-6px); }
  to   { opacity: 1; transform: translateY(0); }
}

.challenge-top {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.1em;
  color: var(--muted);
}

.difficulty {
  font-family: var(--font-mono);
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.14em;
  padding: 3px 8px;
  border-radius: 999px;
  background: var(--paper-2);
  border: 1px solid var(--line);
}
.difficulty.medium { color: var(--indigo); background: var(--indigo-soft); border-color: transparent; }
.difficulty.hard { color: #9A2A2A; background: #FAE1DF; border-color: transparent; }

.challenge-title {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 21px;
  line-height: 1.25;
  letter-spacing: -0.01em;
  margin: 0;
  color: var(--ink);
  flex: 1;
}
.challenge-desc {
  font-size: 14.5px;
  line-height: 1.6;
  color: var(--ink-soft);
  margin: 0;
}
.challenge-context {
  font-size: 12.5px;
  line-height: 1.55;
  color: var(--muted);
  padding-top: 12px;
  margin: 0;
  border-top: 1px dashed var(--line);
  font-style: italic;
}

/* Card CTA — jumps to the Prompts room with the challenge attached */
.card-cta {
  align-self: flex-start;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  margin-top: 4px;
  padding: 10px 16px;
  border-radius: 999px;
  background: var(--ink);
  color: var(--paper);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.01em;
  text-decoration: none;
  border: 1px solid var(--ink);
  transition: background 0.2s, border-color 0.2s, transform 0.2s, color 0.2s;
}
.card-cta svg {
  width: 14px;
  height: 14px;
  transition: transform 0.25s ease;
}
.card-cta:hover {
  background: var(--emerald);
  border-color: var(--emerald);
  transform: translateY(-1px);
}
.card-cta:hover svg { transform: translateX(3px); }

/* ---------- Selected challenge banner (prompts page) ---------- */
.selected-banner {
  margin-top: 28px;
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 14px 20px;
  background: var(--emerald-soft);
  border: 1px solid rgba(14,94,62,0.25);
  border-radius: var(--radius-m);
  flex-wrap: wrap;
}
.sb-label {
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--emerald-ink);
}
.sb-main {
  display: flex;
  align-items: baseline;
  gap: 12px;
  flex: 1;
  min-width: 0;
}
.sb-code {
  font-family: var(--font-mono);
  font-size: 12px;
  color: var(--emerald-ink);
  background: rgba(14,94,62,0.12);
  padding: 3px 8px;
  border-radius: 999px;
}
.sb-title {
  font-family: var(--font-display);
  font-size: 19px;
  letter-spacing: -0.01em;
  color: var(--ink);
  font-weight: 500;
}
.sb-change {
  font-size: 13px;
  color: var(--emerald-ink);
  text-decoration: none;
  border-bottom: 1px dashed rgba(14,94,62,0.5);
  padding-bottom: 1px;
}
.sb-change:hover { border-bottom-style: solid; }

.prompt-text mark.token {
  background: var(--saffron-soft);
  color: var(--saffron-ink);
  padding: 1px 6px;
  border-radius: 4px;
  font-weight: 600;
  font-family: inherit;
}

/* ---------- Prompts page ---------- */
.prompt-intro {
  display: grid;
  grid-template-columns: 1.2fr 1fr;
  gap: 40px;
  align-items: start;
  margin-bottom: 48px;
}
.prompt-flow {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-m);
  padding: 24px;
}
.prompt-flow h4 {
  margin: 0 0 16px;
  font-family: var(--font-mono);
  font-size: 11px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--muted);
}
.flow-step {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 8px 0;
  font-size: 14px;
  color: var(--ink-soft);
  border-top: 1px dashed var(--line);
}
.flow-step:first-of-type { border-top: 0; }
.flow-step .n {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted);
  width: 22px;
}
.flow-step .name {
  font-family: var(--font-display);
  font-weight: 500;
  color: var(--ink);
  font-size: 16px;
  letter-spacing: -0.005em;
}
.flow-step .arrow-small {
  margin-left: auto;
  opacity: 0.5;
  color: var(--emerald);
}

.prompt-list {
  display: flex;
  flex-direction: column;
  gap: 22px;
}

.prompt-card {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 28px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius-l);
  padding: 28px 32px;
  transition: border-color 0.2s, box-shadow 0.25s;
  position: relative;
}
.prompt-card:hover {
  border-color: var(--line-strong);
  box-shadow: var(--shadow-soft);
}

.prompt-head {
  display: flex;
  flex-direction: column;
  gap: 8px;
  border-right: 1px dashed var(--line);
  padding-right: 22px;
}
.prompt-step {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--muted);
  letter-spacing: 0.14em;
}
.prompt-name {
  font-family: var(--font-display);
  font-weight: 500;
  font-size: 34px;
  letter-spacing: -0.02em;
  line-height: 0.98;
  color: var(--ink);
  margin: 0;
}
.prompt-name em { font-style: italic; color: var(--emerald); font-weight: 400; }
.prompt-subtitle {
  font-size: 13px;
  color: var(--muted);
  line-height: 1.5;
  margin-top: 4px;
}

.prompt-body {
  display: flex;
  flex-direction: column;
  gap: 14px;
}
.prompt-actions {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 10px;
}
.btn {
  border: 1px solid var(--ink);
  background: var(--ink);
  color: var(--paper);
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 13px;
  padding: 9px 16px;
  border-radius: 999px;
  cursor: pointer;
  letter-spacing: 0.01em;
  transition: transform 0.2s ease, background 0.2s;
  display: inline-flex;
  align-items: center;
  gap: 8px;
}
.btn:hover { transform: translateY(-1px); background: var(--emerald); border-color: var(--emerald); }
.btn svg { width: 14px; height: 14px; }
.btn.is-copied { background: var(--emerald); border-color: var(--emerald); }

.prompt-tags {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}
.tag {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--ink-soft);
  background: var(--paper-2);
  border: 1px solid var(--line);
  padding: 3px 9px;
  border-radius: 999px;
}

.prompt-text {
  font-family: var(--font-mono);
  font-size: 13.5px;
  color: var(--ink);
  line-height: 1.65;
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius-s);
  padding: 18px 20px;
  white-space: pre-wrap;
  word-wrap: break-word;
}
.prompt-text strong {
  color: var(--emerald-ink);
  font-weight: 600;
}

/* ---------- Footer ---------- */
.site-footer {
  margin-top: auto;
  border-top: 1px solid var(--line);
  background: var(--paper-2);
  padding: 26px 48px;
}
.footer-inner {
  display: grid;
  grid-template-columns: 1fr auto 1fr;
  align-items: center;
  gap: 20px;
  max-width: 1280px;
  margin: 0 auto;
}

.footer-logo {
  display: flex;
  align-items: center;
}
.footer-logo.left { justify-content: flex-start; }
.footer-logo.right { justify-content: flex-end; }
.footer-logo img {
  max-height: 42px;
  width: auto;
  display: block;
}
.footer-logo.left img {
  /* recolor the Tata mark to black to sit alongside the TCS mark */
  filter: brightness(0);
}
.footer-logo.right img {
  max-height: 50px;
  /* blend the TCS logo's white card into the paper background */
  mix-blend-mode: multiply;
}

.footer-center {
  text-align: center;
  font-family: var(--font-display);
  font-style: italic;
  font-weight: 400;
  font-size: 15px;
  color: var(--muted);
  letter-spacing: 0.01em;
}
.footer-center .dot {
  color: var(--saffron);
  font-style: normal;
  margin: 0 10px;
}
.footer-center strong {
  font-style: normal;
  font-weight: 600;
  color: var(--ink);
  font-family: var(--font-body);
  letter-spacing: 0.02em;
}

/* ---------- Anim entry ---------- */
@keyframes rise {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: translateY(0); }
}
.rise { animation: rise 0.6s cubic-bezier(.2,.8,.2,1) both; }
.rise.d1 { animation-delay: 0.05s; }
.rise.d2 { animation-delay: 0.12s; }
.rise.d3 { animation-delay: 0.2s; }
.rise.d4 { animation-delay: 0.28s; }

/* ---------- Responsive ---------- */
@media (max-width: 960px) {
  main { padding: 40px 24px 72px; }
  .topbar { padding: 18px 24px; }
  .site-footer { padding: 22px 24px; }
  .tracks { grid-template-columns: 1fr; }
  .challenge-grid { grid-template-columns: 1fr; }
  .prompt-intro { grid-template-columns: 1fr; }
  .prompt-card { grid-template-columns: 1fr; }
  .prompt-head { border-right: 0; border-bottom: 1px dashed var(--line); padding-right: 0; padding-bottom: 14px; }
  .footer-inner { grid-template-columns: 1fr; text-align: center; }
  .footer-logo.left, .footer-logo.right { justify-content: center; }
}
@media (max-width: 600px) {
  .page-title { font-size: 40px; }
  .prompt-name { font-size: 28px; }
}