/* =====================================================================
   PyQuiz marketing site — "editorial-technical / blueprint" aesthetic.
   Off-white paper, deep navy ink, warm amber accent, algorithmic motifs
   (nodes, connectors, a faint grid). Body type stays Atkinson Hyperlegible
   for dyslexia-friendliness; a characterful display face carries headings.
   ===================================================================== */

@font-face {
  font-family: "Atkinson Hyperlegible";
  src: local("Atkinson Hyperlegible"), local("AtkinsonHyperlegible-Regular");
  font-display: swap;
}

:root {
  --paper: #faf7f2;
  --paper-2: #f2ece0;
  --ink: #16181d;
  --ink-soft: #4a4e57;
  --line: #e0d8c8;
  --line-strong: #c9bfa9;
  --navy: #1e3a5f;
  --navy-deep: #14283f;
  --amber: #e07a00;
  --amber-soft: #f4a93c;
  --teal: #2e8b6b;
  --plum: #7a3e6b;
  --ok: #1e6e3c;

  --display: "Fraunces", Georgia, "Times New Roman", serif;
  --body:
    "Atkinson Hyperlegible", system-ui, -apple-system, "Segoe UI", sans-serif;
  --mono:
    ui-monospace, "Cascadia Mono", "SF Mono", "Source Code Pro", Consolas,
    monospace;

  --radius: 14px;
  --radius-sm: 8px;
  --shadow: 0 1px 2px rgba(20, 18, 12, 0.05), 0 8px 30px rgba(20, 18, 12, 0.06);
  --shadow-lg: 0 20px 60px rgba(20, 40, 63, 0.14);
  --maxw: 1140px;
}

[data-theme="dark"] {
  --paper: #16181d;
  --paper-2: #1e2128;
  --ink: #ece8df;
  --ink-soft: #a6a299;
  --line: #2d313a;
  --line-strong: #3c414c;
  --navy: #8fb4e0;
  --navy-deep: #0e1a2a;
  --amber: #f2a24e;
  --amber-soft: #f4b468;
  --shadow: 0 1px 2px rgba(0, 0, 0, 0.4), 0 8px 30px rgba(0, 0, 0, 0.35);
  --shadow-lg: 0 20px 60px rgba(0, 0, 0, 0.5);
}

* {
  box-sizing: border-box;
}
html {
  scroll-behavior: smooth;
}
body {
  margin: 0;
  font-family: var(--body);
  background: var(--paper);
  color: var(--ink);
  line-height: 1.65;
  font-size: 18px;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

/* Faint algorithmic grid behind everything. */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  background-image:
    linear-gradient(var(--line) 1px, transparent 1px),
    linear-gradient(90deg, var(--line) 1px, transparent 1px);
  background-size: 44px 44px;
  opacity: 0.4;
  pointer-events: none;
  z-index: 0;
  -webkit-mask-image: radial-gradient(
    ellipse 90% 70% at 50% 0%,
    #000 30%,
    transparent 75%
  );
  mask-image: radial-gradient(
    ellipse 90% 70% at 50% 0%,
    #000 30%,
    transparent 75%
  );
}

a {
  color: inherit;
}
img {
  max-width: 100%;
  display: block;
}

.wrap {
  max-width: var(--maxw);
  margin: 0 auto;
  padding: 0 24px;
  position: relative;
  z-index: 1;
}

/* ---------- top bar ---------- */
.site-top {
  position: sticky;
  top: 0;
  z-index: 50;
  backdrop-filter: blur(8px);
  background: color-mix(in srgb, var(--paper) 82%, transparent);
  border-bottom: 1px solid var(--line);
}
.site-top .wrap {
  display: flex;
  align-items: center;
  gap: 18px;
  height: 68px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 11px;
  font-family: var(--display);
  font-weight: 600;
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  text-decoration: none;
}
.brand .mark {
  width: 30px;
  height: 30px;
  flex: 0 0 auto;
}
.site-nav {
  margin-left: auto;
  display: flex;
  align-items: center;
  gap: 8px;
}
.site-nav a.navlink {
  text-decoration: none;
  color: var(--ink-soft);
  padding: 8px 12px;
  border-radius: var(--radius-sm);
  font-size: 0.96rem;
  transition:
    color 0.15s,
    background 0.15s;
}
.site-nav a.navlink:hover {
  color: var(--ink);
  background: var(--paper-2);
}
/* Start-by-code: a student types a pack code straight into the top bar. */
.code-join {
  display: flex;
  align-items: center;
  gap: 6px;
}
.code-join input {
  font-family: ui-monospace, "JetBrains Mono", Consolas, monospace;
  font-size: 0.95rem;
  letter-spacing: 0.08em;
  padding: 9px 12px;
  width: 8.5em;
  border: 2px solid var(--line-strong);
  border-radius: var(--radius-sm);
  background: #fff;
  color: var(--ink);
}
.code-join input::placeholder {
  letter-spacing: normal;
  color: var(--ink-soft);
}
.code-join input:focus-visible {
  outline: 3px solid var(--navy);
  outline-offset: 2px;
  border-color: var(--navy);
}
.code-join .btn {
  padding: 9px 16px;
  font-size: 0.95rem;
}

/* ---------- buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--body);
  font-weight: 700;
  font-size: 1rem;
  padding: 13px 22px;
  border-radius: var(--radius-sm);
  border: 2px solid transparent;
  cursor: pointer;
  text-decoration: none;
  transition:
    transform 0.12s ease,
    box-shadow 0.15s ease,
    background 0.15s,
    color 0.15s;
  white-space: nowrap;
}
.btn:active {
  transform: translateY(1px);
}
.btn-primary {
  background: var(--navy);
  color: #fff;
  box-shadow: 0 6px 18px color-mix(in srgb, var(--navy) 35%, transparent);
}
.btn-primary:hover {
  background: var(--navy-deep);
  transform: translateY(-2px);
  box-shadow: 0 10px 26px color-mix(in srgb, var(--navy) 40%, transparent);
}
.btn-amber {
  background: var(--amber);
  color: #1a1205;
  box-shadow: 0 6px 18px color-mix(in srgb, var(--amber) 38%, transparent);
}
.btn-amber:hover {
  background: var(--amber-soft);
  transform: translateY(-2px);
}
.btn-ghost {
  background: transparent;
  color: var(--ink);
  border-color: var(--line-strong);
}
.btn-ghost:hover {
  border-color: var(--ink);
  background: var(--paper-2);
}
.btn-lg {
  font-size: 1.08rem;
  padding: 16px 28px;
}

/* ---------- hero ---------- */
.hero {
  padding: clamp(48px, 8vw, 110px) 0 64px;
  position: relative;
}
.hero-grid {
  display: grid;
  grid-template-columns: 1.05fr 0.95fr;
  gap: 56px;
  align-items: center;
}
.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 9px;
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--amber);
  font-weight: 700;
  padding: 6px 12px;
  border: 1px solid color-mix(in srgb, var(--amber) 40%, var(--line));
  border-radius: 999px;
  background: color-mix(in srgb, var(--amber) 8%, transparent);
}
.hero h1 {
  font-family: var(--display);
  font-weight: 600;
  font-size: clamp(2.6rem, 6vw, 4.4rem);
  line-height: 1.03;
  letter-spacing: -0.025em;
  margin: 22px 0 0;
}
.hero h1 .ink-accent {
  color: var(--amber);
  font-style: italic;
}
.hero .lede {
  font-size: clamp(1.1rem, 2.2vw, 1.32rem);
  color: var(--ink-soft);
  margin: 22px 0 0;
  max-width: 30ch;
}
.hero-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 14px;
  margin-top: 34px;
}
.hero-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px 18px;
  margin-top: 30px;
  font-size: 0.92rem;
  color: var(--ink-soft);
}
.hero-tags span {
  display: inline-flex;
  align-items: center;
  gap: 7px;
}
.hero-tags .dot {
  width: 7px;
  height: 7px;
  border-radius: 50%;
  background: var(--teal);
}

/* staggered reveal on load */
.reveal {
  opacity: 0;
  transform: translateY(16px);
  animation: rise 0.7s cubic-bezier(0.2, 0.7, 0.3, 1) forwards;
}
@keyframes rise {
  to {
    opacity: 1;
    transform: none;
  }
}
.d1 {
  animation-delay: 0.05s;
}
.d2 {
  animation-delay: 0.15s;
}
.d3 {
  animation-delay: 0.25s;
}
.d4 {
  animation-delay: 0.35s;
}
.d5 {
  animation-delay: 0.45s;
}
.d6 {
  animation-delay: 0.55s;
}
@media (prefers-reduced-motion: reduce) {
  .reveal {
    animation: none;
    opacity: 1;
    transform: none;
  }
}

/* ---------- hero figure: a live-feeling mini flowchart ---------- */
.hero-figure {
  position: relative;
  background: var(--paper-2);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  box-shadow: var(--shadow-lg);
  padding: 26px;
  overflow: hidden;
}
.hero-figure .chip-row {
  display: flex;
  gap: 8px;
  margin-bottom: 18px;
}
.hero-figure .chip {
  font-family: var(--mono);
  font-size: 0.72rem;
  padding: 4px 10px;
  border-radius: 999px;
  border: 1px solid var(--line-strong);
  color: var(--ink-soft);
  background: var(--paper);
}
.hero-figure svg {
  width: 100%;
  height: auto;
  display: block;
}
.fc-node {
  fill: var(--paper);
  stroke: var(--line-strong);
  stroke-width: 1.6;
}
.fc-term {
  fill: color-mix(in srgb, var(--navy) 14%, var(--paper));
}
.fc-dec {
  fill: color-mix(in srgb, var(--amber) 16%, var(--paper));
}
.fc-io {
  fill: color-mix(in srgb, var(--teal) 16%, var(--paper));
}
.fc-edge {
  stroke: var(--line-strong);
  stroke-width: 1.8;
  fill: none;
  marker-end: url(#ar);
}
.fc-label {
  font-family: var(--mono);
  font-size: 11px;
  fill: var(--ink);
}
.fc-elabel {
  font-family: var(--mono);
  font-size: 10px;
  fill: var(--ink-soft);
}
.flow-dash {
  stroke-dasharray: 5 5;
  animation: flow 1.1s linear infinite;
}
@keyframes flow {
  to {
    stroke-dashoffset: -20;
  }
}
@media (prefers-reduced-motion: reduce) {
  .flow-dash {
    animation: none;
  }
}

/* ---------- section scaffolding ---------- */
section {
  position: relative;
  z-index: 1;
}
.section {
  padding: clamp(56px, 8vw, 96px) 0;
}
.section-head {
  max-width: 60ch;
  margin-bottom: 44px;
}
.kicker {
  font-family: var(--mono);
  font-size: 0.8rem;
  letter-spacing: 0.1em;
  text-transform: uppercase;
  color: var(--amber);
  font-weight: 700;
}
.section h2 {
  font-family: var(--display);
  font-weight: 600;
  font-size: clamp(1.9rem, 4vw, 2.8rem);
  line-height: 1.08;
  letter-spacing: -0.02em;
  margin: 12px 0 0;
}
.section .sub {
  color: var(--ink-soft);
  font-size: 1.1rem;
  margin-top: 14px;
}
.alt-bg {
  background: var(--paper-2);
  border-top: 1px solid var(--line);
  border-bottom: 1px solid var(--line);
}

/* ---------- why cards ---------- */
.cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
.card {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
  position: relative;
  overflow: hidden;
  transition:
    transform 0.18s ease,
    box-shadow 0.18s ease,
    border-color 0.18s;
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-lg);
  border-color: var(--line-strong);
}
.card .ic {
  width: 46px;
  height: 46px;
  border-radius: 11px;
  display: grid;
  place-items: center;
  margin-bottom: 16px;
  font-size: 1.4rem;
}
.card h3 {
  font-family: var(--display);
  font-weight: 600;
  font-size: 1.3rem;
  margin: 0 0 8px;
  letter-spacing: -0.01em;
}
.card p {
  margin: 0;
  color: var(--ink-soft);
  font-size: 1rem;
}
.ic-navy {
  background: color-mix(in srgb, var(--navy) 14%, var(--paper));
  color: var(--navy);
}
.ic-amber {
  background: color-mix(in srgb, var(--amber) 16%, var(--paper));
  color: var(--amber);
}
.ic-teal {
  background: color-mix(in srgb, var(--teal) 16%, var(--paper));
  color: var(--teal);
}
.ic-plum {
  background: color-mix(in srgb, var(--plum) 16%, var(--paper));
  color: var(--plum);
}

/* ---------- age band ---------- */
.ks-band {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 14px;
}
.ks {
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 20px 18px;
  background: var(--paper);
  position: relative;
}
.ks .yr {
  font-family: var(--mono);
  font-size: 0.8rem;
  color: var(--amber);
  font-weight: 700;
}
.ks h4 {
  font-family: var(--display);
  font-size: 1.15rem;
  margin: 6px 0 6px;
  font-weight: 600;
}
.ks p {
  margin: 0;
  font-size: 0.92rem;
  color: var(--ink-soft);
}
.ks.paper2 {
  border-color: color-mix(in srgb, var(--amber) 50%, var(--line));
  box-shadow: 0 0 0 1px color-mix(in srgb, var(--amber) 20%, transparent) inset;
}
.ks .badge {
  position: absolute;
  top: -10px;
  right: 12px;
  font-family: var(--mono);
  font-size: 0.66rem;
  background: var(--amber);
  color: #1a1205;
  padding: 3px 8px;
  border-radius: 999px;
  font-weight: 700;
}

/* ---------- workflow boxes ---------- */
.flow-steps {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  position: relative;
}
.flow-step {
  background: var(--paper);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 22px 18px;
  cursor: pointer;
  text-align: left;
  font: inherit;
  color: inherit;
  transition:
    transform 0.15s,
    box-shadow 0.15s,
    border-color 0.15s;
  position: relative;
  z-index: 1;
}
.flow-step + .flow-step {
  margin-left: -1px;
}
.flow-step:hover,
.flow-step[aria-expanded="true"] {
  transform: translateY(-3px);
  box-shadow: var(--shadow-lg);
  border-color: var(--amber);
  z-index: 2;
}
.flow-step .n {
  font-family: var(--mono);
  font-size: 0.78rem;
  color: var(--amber);
  font-weight: 700;
}
.flow-step h4 {
  font-family: var(--display);
  font-size: 1.12rem;
  margin: 8px 0 6px;
  font-weight: 600;
}
.flow-step .tldr {
  font-size: 0.9rem;
  color: var(--ink-soft);
  margin: 0;
}
.flow-detail {
  margin-top: 18px;
  background: var(--paper);
  border: 1px solid var(--amber);
  border-radius: var(--radius);
  padding: 22px 24px;
  box-shadow: var(--shadow);
  display: none;
}
.flow-detail.open {
  display: block;
  animation: rise 0.35s ease forwards;
}
.flow-detail h4 {
  font-family: var(--display);
  margin: 0 0 8px;
  font-size: 1.25rem;
}
.flow-detail p {
  margin: 0 0 10px;
  color: var(--ink-soft);
}
.flow-detail code {
  font-family: var(--mono);
  background: var(--paper-2);
  padding: 2px 6px;
  border-radius: 5px;
  font-size: 0.9em;
}

/* ---------- activity-types strip ---------- */
.types {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 14px;
}
.type-chip {
  border: 1px solid var(--line);
  border-radius: var(--radius-sm);
  padding: 16px;
  background: var(--paper);
}
.type-chip .t {
  font-family: var(--display);
  font-weight: 600;
  font-size: 1.05rem;
}
.type-chip .d {
  font-size: 0.86rem;
  color: var(--ink-soft);
  margin-top: 4px;
}

/* ---------- CTA band ---------- */
.cta-band {
  text-align: center;
}
.cta-band h2 {
  font-family: var(--display);
  font-size: clamp(2rem, 5vw, 3.2rem);
  margin: 0 0 14px;
  font-weight: 600;
  letter-spacing: -0.02em;
}
.cta-band .sub {
  color: var(--ink-soft);
  font-size: 1.15rem;
  max-width: 50ch;
  margin: 0 auto 30px;
}
.cta-pair {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
}

/* ---------- footer ---------- */
.site-foot {
  border-top: 1px solid var(--line);
  padding: 40px 0;
  color: var(--ink-soft);
  font-size: 0.92rem;
}
.site-foot .wrap {
  display: flex;
  justify-content: space-between;
  gap: 20px;
  flex-wrap: wrap;
  align-items: center;
}

/* ---------- responsive ---------- */
@media (max-width: 900px) {
  .hero-grid {
    grid-template-columns: 1fr;
    gap: 36px;
  }
  .hero .lede {
    max-width: 46ch;
  }
  .cards {
    grid-template-columns: 1fr;
  }
  .ks-band {
    grid-template-columns: 1fr 1fr;
  }
  .flow-steps {
    grid-template-columns: 1fr;
  }
  .flow-step + .flow-step {
    margin-left: 0;
    margin-top: -1px;
  }
  .types {
    grid-template-columns: 1fr 1fr;
  }
  .site-nav .navlink.hide-sm {
    display: none;
  }
}
@media (max-width: 540px) {
  .ks-band {
    grid-template-columns: 1fr;
  }
  .types {
    grid-template-columns: 1fr;
  }
  body {
    font-size: 17px;
  }
}

/* Header "Log In" dropdown (Teacher / Student) — a no-JS <details> menu. */
.login-menu {
  position: relative;
  display: inline-block;
}
.login-menu > summary {
  list-style: none;
  cursor: pointer;
}
.login-menu > summary::-webkit-details-marker {
  display: none;
}
.login-menu-pop {
  position: absolute;
  right: 0;
  top: calc(100% + 6px);
  z-index: 40;
  display: flex;
  flex-direction: column;
  min-width: 168px;
  background: #fffdf8;
  border: 1px solid #d8d2c4;
  border-radius: 10px;
  box-shadow: 0 14px 34px -14px rgba(40, 30, 10, 0.45);
  overflow: hidden;
}
.login-menu-pop a {
  padding: 11px 15px;
  text-decoration: none;
  color: #1b1b1f;
  font-weight: 600;
}
.login-menu-pop a + a {
  border-top: 1px solid #ece6da;
}
.login-menu-pop a:hover,
.login-menu-pop a:focus {
  background: #f0ebdc;
  outline: none;
}