/* ==========================================================
   CircuitKids STEM Lab — Stylesheet
   Design language: engineering blueprint + circuit schematic.
   ========================================================== */

@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@500;600;700&family=Nunito:wght@400;600;700;800&family=IBM+Plex+Mono:wght@500;600&display=swap');

:root {
  /* --- Color tokens --- */
  --ink-navy:      #14213D;
  --blueprint:     #2F5C8A;
  --blueprint-lt:  #6F98C4;
  --circuit-amber: #F0A202;
  --safety-orange: #E8551B;
  --paper:         #F6F4EC;
  --paper-dim:     #ECE8DB;
  --graphite:      #2A2A28;
  --grid-line:     rgba(47, 92, 138, 0.14);
  --led-green:     #3FCF7F;

  /* --- Type tokens --- */
  --font-display: 'Space Grotesk', sans-serif;
  --font-body:    'Nunito', sans-serif;
  --font-mono:    'IBM Plex Mono', monospace;

  --radius: 10px;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { animation-duration: 0.001ms !important; animation-iteration-count: 1 !important; transition-duration: 0.001ms !important; }
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--graphite);
  font-family: var(--font-body);
  font-size: 17px;
  line-height: 1.6;
  background-image:
    linear-gradient(var(--grid-line) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-line) 1px, transparent 1px);
  background-size: 32px 32px;
}

img, svg { display: block; max-width: 100%; }
a { color: inherit; }
h1, h2, h3, h4 { font-family: var(--font-display); margin: 0; color: var(--ink-navy); }
p { margin: 0; }
ul { margin: 0; padding: 0; list-style: none; }
button { font-family: inherit; cursor: pointer; }

.wrap {
  max-width: 1120px;
  margin: 0 auto;
  padding: 0 24px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  letter-spacing: 0.14em;
  text-transform: uppercase;
  color: var(--safety-orange);
  font-weight: 600;
}
.eyebrow::before {
  content: '';
  width: 18px;
  height: 2px;
  background: var(--safety-orange);
  display: inline-block;
}

/* ---------------- Circuit rail (signature element) ---------------- */
.circuit-rail {
  position: fixed;
  top: 0;
  left: 28px;
  width: 2px;
  height: 100%;
  background: linear-gradient(to bottom, transparent 0%, var(--blueprint-lt) 6%, var(--blueprint-lt) 94%, transparent 100%);
  opacity: 0.5;
  z-index: 5;
  pointer-events: none;
}
.circuit-rail .pad {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  width: 13px;
  height: 13px;
  border-radius: 3px;
  background: var(--paper);
  border: 2px solid var(--blueprint-lt);
  transition: background 0.4s ease, border-color 0.4s ease, box-shadow 0.4s ease;
}
.circuit-rail .pad.lit {
  background: var(--circuit-amber);
  border-color: var(--circuit-amber);
  box-shadow: 0 0 10px 2px rgba(240, 162, 2, 0.65);
}
@media (max-width: 900px) {
  .circuit-rail { display: none; }
}

/* ---------------- Header ---------------- */
.site-header {
  position: sticky;
  top: 0;
  z-index: 40;
  background: rgba(246, 244, 236, 0.92);
  backdrop-filter: blur(6px);
  border-bottom: 1px solid rgba(20, 33, 61, 0.1);
}
.site-header .wrap {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-top: 16px;
  padding-bottom: 16px;
}
.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-display);
  font-weight: 700;
  font-size: 19px;
  color: var(--ink-navy);
  text-decoration: none;
}
.brand .dot {
  width: 10px; height: 10px; border-radius: 50%;
  background: var(--led-green);
  box-shadow: 0 0 8px 2px rgba(63,207,127,0.7);
}
.site-header nav {
  display: flex;
  align-items: center;
  gap: 28px;
}
.site-header nav a {
  text-decoration: none;
  font-weight: 600;
  font-size: 14.5px;
  color: var(--graphite);
}
.site-header nav a:hover { color: var(--safety-orange); }
@media (max-width: 720px) {
  .site-header nav .nav-links { display: none; }
}

.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 12px 22px;
  border-radius: 999px;
  font-weight: 700;
  font-size: 14.5px;
  text-decoration: none;
  border: none;
  transition: transform 0.15s ease, box-shadow 0.15s ease;
}
.btn-primary {
  background: var(--safety-orange);
  color: #fff;
  box-shadow: 0 6px 18px rgba(232, 85, 27, 0.35);
}
.btn-primary:hover { transform: translateY(-2px); box-shadow: 0 10px 22px rgba(232, 85, 27, 0.42); }
.btn-ghost {
  background: transparent;
  color: var(--ink-navy);
  border: 2px solid rgba(20,33,61,0.18);
}
.btn-ghost:hover { border-color: var(--ink-navy); }

/* ---------------- Hero ---------------- */
.hero {
  padding: 96px 0 80px;
  position: relative;
  overflow: hidden;
}
.hero .wrap { position: relative; z-index: 2; }
.hero h1 {
  font-size: clamp(2.4rem, 5.4vw, 4.1rem);
  line-height: 1.06;
  letter-spacing: -0.01em;
  margin: 18px 0 22px;
  max-width: 100%;
}
.hero h1 .accent { color: var(--safety-orange); }
.hero .lede {
  font-size: 19px;
  max-width: 100%;
  color: #444038;
  margin-bottom: 34px;
}
.hero-actions { display: flex; gap: 16px; flex-wrap: wrap; align-items: center; margin-bottom: 44px; }
.hero-stats {
  display: flex;
  gap: 34px;
  flex-wrap: wrap;
  font-family: var(--font-mono);
}
.hero-stats .stat b {
  display: block;
  font-family: var(--font-display);
  font-size: 26px;
  color: var(--ink-navy);
}
.hero-stats .stat span {
  font-size: 12px;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--blueprint);
}

.hero-art { margin-bottom: 25px; border-radius: 18px; overflow: hidden; border: 1px solid rgba(20,33,61,0.08); background: #fff; }
.circuit-strip { width: 100%; height: auto; display: block; }

/* ---------------- Section shells ---------------- */
section { padding: 76px 0; position: relative; }
.section-head { max-width: 62ch; margin-bottom: 40px; }
.section-head h2 { font-size: clamp(1.7rem, 3vw, 2.4rem); margin-top: 14px; line-height: 1.15; }
.section-head p.sub { margin-top: 14px; font-size: 16.5px; color: #4a463d; }

/* ---------------- Class 1 highlight ---------------- */
.class1 {
  background: var(--ink-navy);
  color: var(--paper);
  border-radius: 20px;
  position: relative;
  overflow: hidden;
}
.class1::after {
  content: '';
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,0.05) 1px, transparent 1px),
                     linear-gradient(90deg, rgba(255,255,255,0.05) 1px, transparent 1px);
  background-size: 26px 26px;
  pointer-events: none;
}
.class1 .wrap {
  position: relative;
  z-index: 1;
  display: grid;
  grid-template-columns: 1.1fr 0.9fr;
  gap: 48px;
  align-items: center;
  padding-top: 64px;
  padding-bottom: 64px;
}
.class1 .eyebrow { color: var(--circuit-amber); }
.class1 .eyebrow::before { background: var(--circuit-amber); }
.class1 h2 { color: #fff; }
.class1 p.sub { color: #C8D2E4; }
.class1-steps { margin-top: 24px; display: flex; flex-direction: column; gap: 14px; }
.class1-step {
  display: flex; gap: 14px; align-items: flex-start;
  font-family: var(--font-mono); font-size: 14px; color: #DCE4F0;
}
.class1-step .tag {
  flex-shrink: 0;
  background: rgba(240,162,2,0.16);
  border: 1px solid rgba(240,162,2,0.5);
  color: var(--circuit-amber);
  padding: 3px 8px;
  border-radius: 5px;
  font-weight: 600;
  font-size: 12px;
}
.class1-diagram { background: rgba(255,255,255,0.04); border: 1px solid rgba(255,255,255,0.12); border-radius: 14px; padding: 20px; }
@media (max-width: 860px) {
  .class1 .wrap { grid-template-columns: 1fr; padding-top: 44px; padding-bottom: 44px; }
}

/* ---------------- Build log grid ---------------- */
.build-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 22px;
}
@media (max-width: 880px) { .build-grid { grid-template-columns: repeat(2, 1fr); } }
@media (max-width: 560px) { .build-grid { grid-template-columns: 1fr; } }

.build-card {
  background: #fff;
  border: 1px solid rgba(20,33,61,0.09);
  border-radius: var(--radius);
  padding: 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}
.build-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 14px 30px rgba(20,33,61,0.09);
  border-color: rgba(232,85,27,0.35);
}
.build-card .refdes {
  font-family: var(--font-mono);
  font-size: 11.5px;
  color: var(--blueprint);
  letter-spacing: 0.08em;
  font-weight: 600;
}
.build-card .icon-box {
  width: 56px; height: 56px;
  border-radius: 10px;
  background: var(--paper-dim);
  display: flex; align-items: center; justify-content: center;
}
.build-card .icon-box svg { width: 30px; height: 30px; stroke: var(--safety-orange); }
.build-card h3 { font-size: 18.5px; }
.build-card p { color: #55514a; font-size: 15px; }

/* ---------------- Before / After ---------------- */
.ba-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border-radius: 16px;
  overflow: hidden;
  border: 1px solid rgba(20,33,61,0.1);
}
@media (max-width: 760px) { .ba-grid { grid-template-columns: 1fr; } }
.ba-panel { padding: 40px 34px; }
.ba-panel.before { background: var(--paper-dim); }
.ba-panel.after { background: var(--ink-navy); color: #fff; }
.ba-panel .ba-label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--blueprint);
  margin-bottom: 12px;
  display: block;
}
.ba-panel.after .ba-label { color: var(--circuit-amber); }
.ba-panel h3 { font-size: 21px; margin-bottom: 12px; }
.ba-panel.after h3 { color: #fff; }
.ba-panel ul { display: flex; flex-direction: column; gap: 10px; }
.ba-panel li { font-size: 15px; padding-left: 22px; position: relative; }
.ba-panel.before li::before { content: '•'; position: absolute; left: 4px; color: var(--blueprint); }
.ba-panel.after li::before { content: '✓'; position: absolute; left: 0; color: var(--led-green); font-weight: 700; }

/* ---------------- Method / teacher ---------------- */
.method {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 54px;
  align-items: center;
}
@media (max-width: 860px) { .method { grid-template-columns: 1fr; } }
.method-quote {
  background: #fff;
  border-left: 4px solid var(--safety-orange);
  border-radius: 0 12px 12px 0;
  padding: 28px 30px;
  font-family: var(--font-display);
  font-size: 21px;
  color: var(--ink-navy);
  line-height: 1.4;
}
.method-quote cite {
  display: block;
  margin-top: 16px;
  font-family: var(--font-mono);
  font-size: 13px;
  color: var(--blueprint);
  font-style: normal;
}
.method-points { display: flex; flex-direction: column; gap: 20px; }
.method-point { display: flex; gap: 16px; }
.method-point .num {
  font-family: var(--font-mono);
  font-weight: 600;
  color: var(--safety-orange);
  border: 1.5px solid rgba(232,85,27,0.4);
  border-radius: 6px;
  width: 34px; height: 34px;
  display: flex; align-items: center; justify-content: center;
  flex-shrink: 0;
  font-size: 13px;
}
.method-point h4 { font-size: 16.5px; margin-bottom: 4px; }
.method-point p { font-size: 14.5px; color: #55514a; }

/* ---------------- Parent reactions ---------------- */
.reactions-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
}
@media (max-width: 880px) { .reactions-grid { grid-template-columns: 1fr; } }
.reaction-card {
  background: #fff;
  border-radius: 14px;
  padding: 26px;
  border: 1px solid rgba(20,33,61,0.09);
  position: relative;
}
.reaction-card .signal {
  font-family: var(--font-mono);
  font-size: 11px;
  color: var(--led-green);
  letter-spacing: 0.1em;
  display: flex;
  align-items: center;
  gap: 6px;
  margin-bottom: 14px;
}
.reaction-card .signal::before {
  content: '';
  width: 7px; height: 7px; border-radius: 50%;
  background: var(--led-green);
  box-shadow: 0 0 6px 1px rgba(63,207,127,0.7);
}
.reaction-card p.quote { font-size: 15.5px; color: #3a3730; margin-bottom: 16px; }
.reaction-card .who { font-family: var(--font-mono); font-size: 12.5px; color: var(--blueprint); }

/* ---------------- Registration ---------------- */
.register {
  background: var(--ink-navy);
  border-radius: 22px;
  color: #fff;
  position: relative;
  overflow: hidden;
}
.register::after {
  content: '';
  position: absolute; inset: 0;
  background-image: linear-gradient(rgba(255,255,255,0.045) 1px, transparent 1px),
                     linear-gradient(90deg, rgba(255,255,255,0.045) 1px, transparent 1px);
  background-size: 26px 26px;
}
.register .wrap { position: relative; z-index: 1; padding-top: 64px; padding-bottom: 64px; }
.register-grid { display: grid; grid-template-columns: 0.9fr 1.1fr; gap: 50px; }
@media (max-width: 900px) { .register-grid { grid-template-columns: 1fr; } }
.register .eyebrow { color: var(--circuit-amber); }
.register .eyebrow::before { background: var(--circuit-amber); }
.register h2 { color: #fff; margin-top: 14px; }
.register p.sub { color: #C8D2E4; margin-top: 14px; }

.led-indicator {
  margin-top: 30px;
  display: inline-flex;
  align-items: center;
  gap: 10px;
  font-family: var(--font-mono);
  font-size: 12.5px;
  color: #8FA3C4;
}
.led-indicator .bulb {
  width: 12px; height: 12px; border-radius: 50%;
  background: #33415F;
  border: 1px solid #4A5C82;
  transition: all 0.4s ease;
}
.led-indicator.on .bulb {
  background: var(--led-green);
  box-shadow: 0 0 12px 3px rgba(63,207,127,0.8);
}
.led-indicator.on { color: var(--led-green); }

form.reg-form {
  background: rgba(255,255,255,0.05);
  border: 1px solid rgba(255,255,255,0.14);
  border-radius: 16px;
  padding: 28px;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}
form.reg-form .full { grid-column: 1 / -1; }
@media (max-width: 560px) { form.reg-form { grid-template-columns: 1fr; padding: 20px; } }

.field label {
  display: block;
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: #AEBBD6;
  margin-bottom: 7px;
}
.field input, .field select, .field textarea {
  width: 100%;
  padding: 12px 14px;
  border-radius: 8px;
  border: 1px solid rgba(255,255,255,0.2);
  background: rgba(255,255,255,0.06);
  color: #fff;
  font-family: var(--font-body);
  font-size: 15px;
}
.field input::placeholder, .field textarea::placeholder { color: #7C8CAE; }
.field input:focus, .field select:focus, .field textarea:focus {
  outline: 2px solid var(--circuit-amber);
  outline-offset: 1px;
  border-color: transparent;
}
.field select option { color: #111; }
.hp-field { position: absolute; left: -9999px; opacity: 0; }

.form-msg {
  grid-column: 1 / -1;
  padding: 12px 14px;
  border-radius: 8px;
  font-size: 14.5px;
  font-weight: 600;
}
.form-msg.success { background: rgba(63,207,127,0.15); border: 1px solid rgba(63,207,127,0.4); color: #AFF3CB; }
.form-msg.error { background: rgba(232,85,27,0.15); border: 1px solid rgba(232,85,27,0.4); color: #FFC7B0; }

/* ---------------- Footer ---------------- */
footer {
  border-top: 1px solid rgba(20,33,61,0.12);
  padding: 40px 0;
}
footer .wrap {
  display: flex;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 16px;
  font-size: 14px;
  color: #6b6759;
}
footer a.admin-link { font-family: var(--font-mono); font-size: 12px; color: #9a968a; text-decoration: none; }

/* ---------------- Reveal-on-scroll ---------------- */
/* Hidden state only applies once JS has confirmed it's running (see the
   inline script in <head>). If JS fails to load or run for any reason,
   sections stay visible by default instead of being stuck at opacity:0. */
html.js-ready .reveal { opacity: 0; transform: translateY(18px); transition: opacity 0.6s ease, transform 0.6s ease; }
html.js-ready .reveal.in { opacity: 1; transform: translateY(0); }