/* Alpha Academy — website
   Design system: DESIGN.md (industrial / instrument panel).
   Depth by tone, never by shadow. One hot action per page.
   One paper surface per page, reserved for the letter. */

:root {
  /* Surfaces */
  --bg:             #11162C;
  --surface:        #1C2137;
  --surface-deep:   #061944;
  --surface-deep-2: #14264E;
  --bar:            #0D1021;
  --chip:           #282D41;
  --paper:          #B6CCFB;

  /* Accents */
  --hot:         #D26A05;
  --hot-pressed: #B35309;
  --blue:        #2459F5;
  --blue-bright: #448DFF;
  --glow:        #1B3A71;

  /* Semantic */
  --positive: #77D2B4;
  --negative: #F0616B;
  --amber:    #EFC26A;
  --track:    #2B3350;

  /* Text */
  --ink:       #F2F5FF;
  --ink2:      #8B90AB;
  --ink3:      #6A6F85;
  --on-paper:  #0B1220;
  --on-paper2: #3C4A6B;

  /* Type */
  --ui: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", Roboto,
        Helvetica, Arial, sans-serif;
  --serif: "Instrument Serif", Georgia, "Times New Roman", serif;
  --mono: "IBM Plex Mono", ui-monospace, "SF Mono", Menlo, Consolas, monospace;

  /* Radii — cards 20 · buttons 14 · bar 28 */
  --r-card: 20px;
  --r-btn: 14px;
  --r-tile: 9px;
}

* { box-sizing: border-box; }

html { -webkit-text-size-adjust: 100%; scroll-behavior: smooth; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--ui);
  font-size: 16px;
  line-height: 1.55;
  -webkit-font-smoothing: antialiased;
}

/* Every numeral the user reads is mono with tabular figures. No exceptions. */
.num, .mono {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-feature-settings: "tnum" 1;
}

a { color: var(--blue-bright); text-decoration: none; }
a:hover { text-decoration: underline; }

.wrap { width: 100%; max-width: 920px; margin: 0 auto; padding: 0 16px; }

/* ── Masthead ─────────────────────────────────────────────── */

.masthead {
  background: var(--bar);
  border-bottom: 1px solid var(--track);
  position: sticky;
  top: 0;
  z-index: 10;
}

.masthead .wrap {
  display: flex;
  align-items: center;
  gap: 14px;
  min-height: 62px;
  flex-wrap: wrap;
  padding-top: 8px;
  padding-bottom: 8px;
}

.wordmark {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  color: var(--ink);
  font-size: 17px;
  font-weight: 600;
  letter-spacing: -0.2px;
}
.wordmark:hover { text-decoration: none; }

.mark {
  width: 30px;
  height: 30px;
  border-radius: var(--r-tile);
  background: var(--chip);
  border: 1px solid var(--track);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  font-family: var(--serif);
  font-size: 21px;
  line-height: 1;
  color: var(--blue-bright);
}

.tagline {
  font-size: 12px;
  color: var(--ink3);
  letter-spacing: 1.3px;
  text-transform: uppercase;
  font-weight: 600;
}

.nav { margin-left: auto; display: flex; gap: 18px; }
.nav a { color: var(--ink2); font-size: 14px; font-weight: 500; }
.nav a:hover { color: var(--ink); text-decoration: none; }
.nav a.on { color: var(--ink); }

/* ── Blocks ───────────────────────────────────────────────── */

main { padding: 24px 0 8px; }

.hero { padding: 24px 0 8px; }

.kicker {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 1.3px;
  text-transform: uppercase;
  color: var(--ink3);
  margin-bottom: 8px;
}

h1 {
  font-size: 40px;
  line-height: 1.1;
  letter-spacing: -0.8px;
  font-weight: 600;
  margin: 0 0 14px;
}

h2 {
  font-size: 26px;
  line-height: 1.2;
  letter-spacing: -0.3px;
  font-weight: 600;
  margin: 0 0 12px;
}

h3 {
  font-size: 17px;
  font-weight: 600;
  margin: 0 0 4px;
}

p { margin: 0 0 12px; }

.lede { font-size: 17px; color: var(--ink2); max-width: 620px; }
.dim { color: var(--ink2); }
.hot-text { color: var(--hot); }

.card {
  background: var(--surface);
  border-radius: var(--r-card);
  padding: 24px;
  margin: 14px 0;
}

.card.deep { background: var(--surface-deep); }

.card > :last-child { margin-bottom: 0; }

section + section { margin-top: 24px; }

/* ── The one paper surface: the letter plate ──────────────── */

.plate {
  background: var(--paper);
  color: var(--on-paper);
  border-radius: var(--r-card);
  padding: 22px 24px 26px;
  margin: 24px 0;
  display: flex;
  align-items: center;
  gap: 24px;
}

.plate .glyph {
  font-family: var(--serif);
  font-size: 120px;
  line-height: 0.86;
  height: 103px;              /* size × 0.86 — the face carries a generous line box */
  display: block;
  color: var(--on-paper);
}

.plate .word {
  font-size: 19px;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 3px;
  margin-bottom: 6px;
}

.plate .key {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 1.5px;
  color: var(--on-paper2);
  margin-bottom: 10px;
}

.plate .mnemonic {
  font-size: 14px;
  color: var(--on-paper2);
  max-width: 320px;
}

/* ── Buttons — exactly one hot per page ───────────────────── */

.cta-row { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 20px; }

.btn {
  display: inline-block;
  padding: 13px 22px;
  border-radius: var(--r-btn);
  font-size: 15px;
  font-weight: 600;
  color: var(--ink);
  background: var(--chip);
  transition: background 180ms ease-out;
}
.btn:hover { text-decoration: none; background: var(--track); }

.btn.hot { background: var(--hot); color: #FFF; }
.btn.hot:hover { background: var(--hot-pressed); }

.btn.ghost { background: transparent; border: 1px solid var(--track); color: var(--ink2); }
.btn.ghost:hover { color: var(--ink); background: transparent; border-color: var(--ink3); }

/* ── Stat strip ───────────────────────────────────────────── */

.stats {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(120px, 1fr));
  gap: 12px;
  margin-top: 4px;
}

.stat {
  background: var(--surface-deep-2);
  border-radius: var(--r-tile);
  padding: 14px 16px;
}

.stat .label {
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 1.3px;
  text-transform: uppercase;
  color: var(--ink3);
  margin-bottom: 6px;                /* micro-labels sit above their value */
}

.stat .value {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 22px;
  font-weight: 600;
  letter-spacing: -1px;
}

/* ── Steps ────────────────────────────────────────────────── */

.step { display: flex; gap: 16px; padding: 14px 0; }
.step + .step { border-top: 1px solid var(--track); }

.step .n {
  flex: 0 0 34px;
  height: 34px;
  border-radius: var(--r-tile);
  background: var(--chip);
  color: var(--blue-bright);
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 15px;
  font-weight: 600;
  display: flex;
  align-items: center;
  justify-content: center;
}

.step p { color: var(--ink2); font-size: 15px; margin: 0; }

/* ── Grids ────────────────────────────────────────────────── */

.grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
  gap: 12px;
}

.tile {
  background: var(--surface-deep-2);
  border-radius: var(--r-tile);
  padding: 16px;
}

.card.deep .tile { background: var(--surface-deep-2); }

.tile h3 { font-size: 16px; }
.tile p { color: var(--ink2); font-size: 14px; margin: 0; }

.tile .tag {
  display: inline-block;
  font-family: var(--mono);
  font-size: 11px;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--ink3);
  margin-bottom: 8px;
}

.chips { display: flex; flex-wrap: wrap; gap: 8px; margin-top: 4px; }

.chip {
  background: var(--chip);
  border-radius: 999px;
  padding: 7px 14px;
  font-size: 13px;
  color: var(--ink);
}

.chip .ex {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  color: var(--ink2);
  margin-left: 8px;
}

/* ── Mastery meter ────────────────────────────────────────── */

.meters { display: grid; gap: 10px; margin-top: 4px; }

.meter-row { display: flex; align-items: center; gap: 12px; }

.meter-row .sym {
  font-family: var(--serif);
  font-size: 21px;
  width: 22px;
  color: var(--ink);
}

.meter-row .who { font-size: 14px; color: var(--ink2); width: 96px; }

.meter {
  flex: 1;
  height: 8px;
  border-radius: 999px;
  background: var(--track);
  overflow: hidden;
}

.meter i { display: block; height: 100%; background: var(--blue); border-radius: 999px; }
.meter i.full { background: var(--positive); }
.meter i.weak { background: var(--amber); }

.meter-row .lv {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  color: var(--ink3);
  width: 34px;
  text-align: right;
}

/* ── Chart table ──────────────────────────────────────────── */

.chart { width: 100%; border-collapse: collapse; margin-top: 4px; }

.chart th {
  text-align: left;
  font-size: 10px;
  font-weight: 600;
  letter-spacing: 1.3px;
  text-transform: uppercase;
  color: var(--ink3);
  padding: 0 0 10px;
}

.chart td { padding: 9px 0; border-top: 1px solid var(--track); font-size: 15px; }

.chart td.sym { font-family: var(--serif); font-size: 24px; width: 48px; }

.chart td.word {
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 3px;
  font-size: 15px;
}

.chart td.key {
  font-family: var(--mono);
  font-size: 13px;
  letter-spacing: 1.5px;
  color: var(--ink2);
  text-align: right;
}

/* ── Badges ───────────────────────────────────────────────── */

.badges { display: grid; grid-template-columns: repeat(auto-fit, minmax(210px, 1fr)); gap: 10px; }

.badge {
  background: var(--surface-deep-2);
  border-radius: var(--r-tile);
  padding: 13px 15px;
}

.badge h3 { font-size: 15px; margin-bottom: 2px; }
.badge p { font-size: 13px; color: var(--ink2); margin: 0; }

/* ── Legal / prose pages ──────────────────────────────────── */

.prose h2 { font-size: 20px; margin-top: 28px; }
.prose h3 { font-size: 16px; margin-top: 18px; color: var(--ink); }
.prose p, .prose li { color: var(--ink2); font-size: 15px; }
.prose ul { padding-left: 20px; margin: 0 0 12px; }
.prose li { margin-bottom: 6px; }
.prose strong { color: var(--ink); font-weight: 600; }
.prose > h2:first-child { margin-top: 0; }

.updated {
  font-family: var(--mono);
  font-variant-numeric: tabular-nums;
  font-size: 13px;
  color: var(--ink3);
}

.callout {
  background: var(--surface-deep-2);
  border-radius: var(--r-tile);
  padding: 14px 16px;
  margin: 14px 0;
}
.callout p { margin: 0; font-size: 14px; }

.faq { padding: 16px 0; }
.faq + .faq { border-top: 1px solid var(--track); }
.faq h3 { margin-bottom: 6px; }
.faq p { color: var(--ink2); font-size: 15px; margin: 0 0 8px; }
.faq p:last-child { margin-bottom: 0; }

.fineprint {
  margin-top: 18px;
  padding-top: 14px;
  border-top: 1px solid var(--track);
}
.fineprint p { font-size: 12px; color: var(--ink3); margin: 0; }

/* ── Footer ───────────────────────────────────────────────── */

.footer {
  background: var(--bar);
  border-top: 1px solid var(--track);
  margin-top: 32px;
  padding: 28px 0 36px;
}

.footer p { color: var(--ink2); font-size: 14px; margin: 0 0 8px; }
.footer .nav-foot { display: flex; gap: 16px; margin-top: 12px; }
.footer .copy { color: var(--ink3); font-size: 13px; margin-top: 12px; }

/* ── Narrow screens ───────────────────────────────────────── */

@media (max-width: 560px) {
  h1 { font-size: 32px; }
  h2 { font-size: 22px; }
  .card { padding: 18px; }
  .plate { flex-direction: column; align-items: flex-start; gap: 14px; padding: 20px; }
  .plate .glyph { font-size: 96px; height: 82px; }
  .masthead .tagline { display: none; }
  .meter-row .who { display: none; }
}

/* Motion is minimal-functional: if it only celebrates, cut it. */
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  * { transition: none !important; }
}