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

.share-tech-mono-regular {
  font-family: "Share Tech Mono", monospace;
  font-weight: 400;
  font-style: normal;
}

:root {
  --bg:        #4d596b;
  --dark:      #2d2e3b;
  --darker:    #1f202a;
  --light:     #869aba;
  --light-2:   #b8c4db;
  --accent:    #a8b8d8;
  --radius:    10px;
  --ease:      cubic-bezier(.2,.7,.2,1);
  --mono:      "Share Tech Mono", monospace;
}

html, body {
  height: 100%;
  width: 100%;
  font-family: var(--mono);
  font-weight: 400;
  color: var(--light-2);
  background-color: var(--bg);
  /* Dotted grid background */
  background-image: radial-gradient(circle, rgba(134, 154, 186, 0.28) 1px, transparent 1px);
  background-size: 22px 22px;
  background-attachment: fixed;
  overflow-x: hidden;
  line-height: 1.6;
  letter-spacing: 0.01em;
}

body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(60% 45% at 15% 10%, rgba(134, 154, 186, 0.12), transparent 70%),
    radial-gradient(50% 40% at 85% 90%, rgba(45, 46, 59, 0.55), transparent 70%);
  z-index: 0;
}

.hidden { display: none !important; }

/* INTRO PAGE */
.intro-page {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 40px 20px;
}

.intro-wrapper {
  text-align: center;
  max-width: 820px;
  width: 100%;
}

.intro-eyebrow {
  font-size: clamp(0.75rem, 1vw, 0.9rem);
  letter-spacing: 0.35em;
  color: var(--light);
  margin-bottom: 18px;
  opacity: 0.8;
}

.intro-title {
  font-family: var(--mono);
  font-size: clamp(3rem, 9vw, 6.5rem);
  color: var(--light-2);
  letter-spacing: 0.06em;
  margin-bottom: 18px;
  line-height: 1;
  text-shadow: 0 0 30px rgba(134, 154, 186, 0.25);
}
.intro-title .slash { color: var(--light); }

.intro-sub {
  color: var(--light);
  font-size: clamp(1rem, 1.6vw, 1.25rem);
  max-width: 620px;
  margin: 0 auto 64px;
  letter-spacing: 0.02em;
}

/* The big SPACE bar */
.space-bar {
  position: relative;
  width: clamp(280px, 55vw, 560px);
  height: clamp(76px, 11vw, 104px);
  border: none;
  border-radius: 12px;
  cursor: pointer;
  font-family: var(--mono);
  font-size: clamp(1.1rem, 2vw, 1.6rem);
  letter-spacing: 0.45em;
  color: var(--light-2);
  background: linear-gradient(180deg, #3a4255 0%, var(--dark) 100%);
  box-shadow:
    0 9px 0 var(--darker),
    0 14px 26px rgba(0,0,0,0.45),
    inset 0 1px 0 rgba(255,255,255,0.06),
    inset 0 0 0 1px rgba(134, 154, 186, 0.25);
  transition: transform 0.08s var(--ease), box-shadow 0.08s var(--ease);
}

.space-bar .space-label { display: inline-block; }
.space-bar .space-hint {
  position: absolute;
  right: 22px; top: 50%;
  transform: translateY(-50%);
  color: var(--light);
  font-size: 1rem;
  opacity: 0.7;
  letter-spacing: 0;
}

.space-bar::after {
  content: "";
  position: absolute;
  inset: 6px 10px auto 10px;
  height: 2px;
  border-radius: 2px;
  background: linear-gradient(90deg, transparent, rgba(134,154,186,0.4), transparent);
  opacity: 0.6;
}

.space-bar:hover {
  transform: translateY(-1px);
  box-shadow:
    0 10px 0 var(--darker),
    0 16px 32px rgba(0,0,0,0.5),
    inset 0 1px 0 rgba(255,255,255,0.06),
    inset 0 0 0 1px rgba(134, 154, 186, 0.45);
}

.space-bar:active,
.space-bar.pressed {
  transform: translateY(7px);
  box-shadow:
    0 2px 0 var(--darker),
    0 3px 6px rgba(0,0,0,0.3),
    inset 0 1px 0 rgba(255,255,255,0.04),
    inset 0 0 0 1px rgba(134, 154, 186, 0.3);
}

.intro-prompt {
  margin-top: 56px;
  color: var(--light);
  font-family: var(--mono);
  font-size: clamp(0.9rem, 1.2vw, 1.05rem);
  letter-spacing: 0.06em;
}
.intro-prompt kbd {
  display: inline-block;
  padding: 3px 10px;
  margin: 0 4px;
  border-radius: 4px;
  background: var(--dark);
  color: var(--light-2);
  border: 1px solid rgba(134,154,186,0.3);
  box-shadow: 0 2px 0 var(--darker);
  font-family: var(--mono);
  font-size: 0.9rem;
}
.intro-prompt .click-word {
  font-style: italic;
  color: var(--light-2);
  border-bottom: 1px dashed var(--light);
  padding-bottom: 1px;
}

/* MAIN PAGE */
.main-page {
  position: relative;
  z-index: 1;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

/*  NAV  */
.nav {
  position: sticky;
  top: 0;
  z-index: 10;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 30px;
  padding: 18px clamp(20px, 4vw, 48px);
  background: rgba(31, 32, 42, 0.72);
  backdrop-filter: blur(10px);
  -webkit-backdrop-filter: blur(10px);
  border-bottom: 1px solid rgba(134,154,186,0.15);
  flex-wrap: wrap;
}

.nav-logo {
  font-family: var(--mono);
  font-size: 1.2rem;
  letter-spacing: 0.14em;
  color: var(--light-2);
}
.nav-logo .slash { color: var(--light); }

.nav-keys {
  display: flex;
  gap: 10px;
  flex-wrap: wrap;
  align-items: flex-end;
}

/* Mechanical Key Button */
.key-btn {
  position: relative;
  padding: 10px 16px 12px;
  border: none;
  cursor: pointer;
  font-family: var(--mono);
  color: var(--light-2);
  background: linear-gradient(180deg, #3a4255 0%, var(--dark) 100%);
  border-radius: 8px;
  text-align: center;
  box-shadow:
    0 5px 0 var(--darker),
    0 8px 14px rgba(0,0,0,0.4),
    inset 0 1px 0 rgba(255,255,255,0.06),
    inset 0 0 0 1px rgba(134, 154, 186, 0.22);
  transition: transform 0.07s var(--ease), box-shadow 0.07s var(--ease), color 0.2s;
}

/* Varying type sizes across buttons */
.key-btn .key-top {
  display: block;
  letter-spacing: 0.12em;
}
.key-btn .key-sub {
  display: block;
  font-size: 0.58rem;
  color: var(--light);
  margin-top: 3px;
  letter-spacing: 0.1em;
}

/* All nav keys render at same size, regardless of size-* class */
.key-btn.size-sm,
.key-btn.size-md,
.key-btn.size-lg,
.key-btn.size-xl {
  min-width: 110px;
  padding: 11px 18px 13px;
}
.key-btn.size-sm .key-top,
.key-btn.size-md .key-top,
.key-btn.size-lg .key-top,
.key-btn.size-xl .key-top {
  font-size: 0.95rem;
}

.key-btn::after {
  content: "";
  position: absolute;
  left: 8px; right: 8px; top: 4px;
  height: 1px;
  background: linear-gradient(90deg, transparent, rgba(134,154,186,0.35), transparent);
  border-radius: 1px;
}

.key-btn:hover {
  transform: translateY(-1px);
  box-shadow:
    0 6px 0 var(--darker),
    0 10px 18px rgba(0,0,0,0.45),
    inset 0 1px 0 rgba(255,255,255,0.06),
    inset 0 0 0 1px rgba(134, 154, 186, 0.45);
  color: #fff;
}

.key-btn:active,
.key-btn.pressed {
  transform: translateY(4px);
  box-shadow:
    0 1px 0 var(--darker),
    0 2px 4px rgba(0,0,0,0.3),
    inset 0 1px 0 rgba(255,255,255,0.04),
    inset 0 0 0 1px rgba(134, 154, 186, 0.3);
}

.key-btn.is-current {
  color: #fff;
  box-shadow:
    0 5px 0 var(--darker),
    0 8px 18px rgba(134, 154, 186, 0.25),
    inset 0 1px 0 rgba(255,255,255,0.08),
    inset 0 0 0 1px rgba(134, 154, 186, 0.65),
    0 0 12px rgba(134, 154, 186, 0.25);
}
.key-btn.is-current .key-sub { color: var(--light-2); }

/* Content */
.content {
  flex: 1;
  max-width: 1200px;
  width: 100%;
  margin: 0 auto;
  padding: clamp(32px, 5vw, 72px) clamp(20px, 4vw, 48px) 96px;
}

.section {
  display: none;
  animation: fadeUp 0.45s var(--ease);
}
.section.active { display: block; }

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(12px); }
  to   { opacity: 1; transform: translateY(0); }
}

/* Type hierarchy (varied) */
.section-head { margin-bottom: 44px; }

.section-tag {
  display: inline-block;
  font-size: 0.78rem;
  letter-spacing: 0.25em;
  color: var(--light);
  padding: 5px 12px;
  border: 1px solid rgba(134,154,186,0.3);
  border-radius: 4px;
  margin-bottom: 22px;
  background: rgba(45, 46, 59, 0.5);
}

.section-head h2 {
  font-family: var(--mono);
  font-weight: 400;
  font-size: clamp(2rem, 4.2vw, 3.4rem);
  color: #fff;
  line-height: 1.1;
  letter-spacing: 0.005em;
  max-width: 900px;
}

.section-kicker {
  color: var(--light);
  margin-top: 18px;
  max-width: 760px;
  font-size: clamp(1rem, 1.3vw, 1.2rem);
  letter-spacing: 0.02em;
}

.sub-heading {
  font-family: var(--mono);
  font-weight: 400;
  color: #fff;
  font-size: clamp(1.4rem, 2.2vw, 1.9rem);
  letter-spacing: 0.02em;
  margin: 44px 0 14px;
  padding-bottom: 10px;
  border-bottom: 1px solid rgba(134,154,186,0.18);
}

/* Card titles at different sizes */
.card-title-sm { font-size: 1.05rem; color: #fff; margin-bottom: 8px; font-weight: 400; letter-spacing: 0.02em; }
.card-title-md { font-size: 1.25rem; color: #fff; margin-bottom: 10px; font-weight: 400; letter-spacing: 0.02em; }
.card-title-lg { font-size: 1.5rem;  color: #fff; margin-bottom: 14px; font-weight: 400; letter-spacing: 0.02em; }

/* Two column (Intro) */
.two-col {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 40px;
  align-items: start;
}
.two-col p {
  margin-bottom: 18px;
  color: var(--light-2);
  font-size: 1.02rem;
}
.two-col .lead {
  font-size: clamp(1.15rem, 1.7vw, 1.35rem);
  color: #fff;
  line-height: 1.5;
}

/* Card */
.card {
  position: relative;
  background: linear-gradient(180deg, rgba(45, 46, 59, 0.85) 0%, rgba(31, 32, 42, 0.85) 100%);
  border: 1px solid rgba(134,154,186,0.18);
  border-radius: var(--radius);
  padding: 26px;
  transition: border-color 0.25s, transform 0.25s;
}
.card:hover {
  border-color: rgba(134,154,186,0.45);
  transform: translateY(-2px);
}

.card p { color: var(--light-2); font-size: 0.98rem; }

.card ul { list-style: none; padding: 0; }
.card ul li {
  padding: 9px 0;
  border-bottom: 1px solid rgba(134,154,186,0.12);
  color: var(--light-2);
  font-size: 1rem;
  position: relative;
  padding-left: 20px;
  letter-spacing: 0.01em;
}
.card ul li::before {
  content: "›";
  position: absolute;
  left: 2px;
  color: var(--light);
}
.card ul li:last-child { border-bottom: none; }

.glow-card {
  background:
    linear-gradient(180deg, rgba(45, 46, 59, 0.85), rgba(31, 32, 42, 0.85)),
    radial-gradient(circle at top left, rgba(134,154,186,0.25), transparent 70%);
  box-shadow: 0 0 40px rgba(134,154,186,0.08);
}

/* Timeline (History) */
.timeline {
  position: relative;
  margin-left: 14px;
  padding-left: 30px;
  border-left: 1px solid rgba(134,154,186,0.25);
}
.timeline-item { position: relative; margin-bottom: 30px; }
.timeline-item::before {
  content: "";
  position: absolute;
  left: -37px;
  top: 12px;
  width: 10px; height: 10px;
  background: var(--light);
  border-radius: 50%;
  box-shadow: 0 0 0 4px rgba(134,154,186,0.15);
}
.timeline-year {
  font-family: var(--mono);
  color: var(--light);
  font-size: 1rem;
  letter-spacing: 0.14em;
  margin-bottom: 8px;
}
.timeline-card {
  background: linear-gradient(180deg, rgba(45, 46, 59, 0.85) 0%, rgba(31, 32, 42, 0.85) 100%);
  border: 1px solid rgba(134,154,186,0.18);
  border-radius: var(--radius);
  padding: 20px 24px;
}
.timeline-card p  { color: var(--light-2); font-size: 0.98rem; }

/* Parts grid  */
.parts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(270px, 1fr));
  gap: 18px;
}
.parts-grid .card-num {
  font-family: var(--mono);
  color: var(--light);
  font-size: 0.85rem;
  letter-spacing: 0.2em;
  margin-bottom: 10px;
}

/*  Layouts grid */
.layouts-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
  margin-bottom: 28px;
}
.layout-card {
  position: relative;
  padding: 22px 22px 26px;
}
.layout-pct {
  position: absolute;
  top: 16px;
  right: 18px;
  font-family: var(--mono);
  color: var(--light);
  font-size: 0.85rem;
  letter-spacing: 0.08em;
}
.layout-bar {
  margin-top: 14px;
  height: 6px;
  background: rgba(134,154,186,0.1);
  border-radius: 3px;
  overflow: hidden;
}
.layout-bar > span {
  display: block;
  height: 100%;
  background: linear-gradient(90deg, var(--light), var(--light-2));
  border-radius: 3px;
  box-shadow: 0 0 8px rgba(134,154,186,0.4);
}

/* Switch grid */
.switch-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 18px;
}
.switch-card { padding: 24px; }
.switch-tag {
  display: inline-block;
  font-size: 0.75rem;
  letter-spacing: 0.25em;
  color: var(--light);
  padding: 3px 10px;
  border: 1px solid rgba(134,154,186,0.3);
  border-radius: 4px;
  margin-bottom: 14px;
  background: rgba(45, 46, 59, 0.5);
}
.switch-linear  .switch-tag { color: #e6a3a3; border-color: rgba(230,163,163,0.35); }
.switch-tactile .switch-tag { color: #d3b48a; border-color: rgba(211,180,138,0.35); }
.switch-clicky  .switch-tag { color: #9ab8e0; border-color: rgba(154,184,224,0.4); }
.switch-special .switch-tag { color: #b8c4db; border-color: rgba(184,196,219,0.35); }

/* Sources */
.sources-list {
  list-style: none;
  display: grid;
  gap: 16px;
  max-width: 840px;
}
.sources-list li {
  display: flex;
  flex-direction: column;
  gap: 6px;
  padding: 20px 24px;
  background: linear-gradient(180deg, rgba(45, 46, 59, 0.85) 0%, rgba(31, 32, 42, 0.85) 100%);
  border: 1px solid rgba(134,154,186,0.18);
  border-radius: var(--radius);
  transition: border-color 0.25s;
}
.sources-list li:hover { border-color: rgba(134,154,186,0.45); }
.sources-list a {
  color: #fff;
  font-size: 1.15rem;
  text-decoration: none;
  border-bottom: 1px dashed rgba(134,154,186,0.5);
  padding-bottom: 2px;
  width: fit-content;
  letter-spacing: 0.02em;
}
.sources-list a:hover { color: var(--light-2); }
.sources-list span { color: var(--light); font-size: 0.95rem; }

.footer-note {
  margin-top: 42px;
  text-align: center;
  font-family: var(--mono);
  font-size: 0.82rem;
  letter-spacing: 0.22em;
  color: var(--light);
  opacity: 0.7;
}

/* RESPONSIVE */
@media (max-width: 820px) {
  .two-col { grid-template-columns: 1fr; }
  .nav {
    justify-content: center;
    padding: 14px 16px;
  }
  .nav-keys { justify-content: center; gap: 8px; }
  .key-btn.size-sm,
  .key-btn.size-md,
  .key-btn.size-lg,
  .key-btn.size-xl {
    min-width: 78px;
    padding: 8px 12px 10px;
  }
  .key-btn .key-top { font-size: 0.72rem !important; }
  .key-btn .key-sub { font-size: 0.55rem; }
}

@media (max-width: 480px) {
  .intro-prompt { font-size: 0.85rem; }
  .space-bar { letter-spacing: 0.28em; }
  .section-head h2 { font-size: 1.7rem; }
  .sub-heading { font-size: 1.25rem; }
  .timeline { padding-left: 22px; margin-left: 6px; }
  .timeline-item::before { left: -29px; }
}

/* Reduced motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}