/* ============================================================
   CATBACK intro — cinematic boot overlay (js/intro.js).

   html[data-intro="pending"] shows the cover BEFORE any JS runs
   so the site never flashes. Everything here is scoped to the
   #intro-screen overlay and its own children — the frozen hero
   simulator is never touched. Tokens only, transform/opacity
   motion only, stepped where it sells the pixel feel.
   ============================================================ */

/* ---- pre-JS gate: instant full-viewport cover ---- */
.intro-screen {
  position: fixed;
  inset: 0;
  z-index: var(--z-intro);
  display: none;
  overflow: hidden;
  background: var(--ink);
  transition: opacity 280ms var(--ease-mech);
}
html[data-intro="pending"] .intro-screen { display: block; }
html[data-intro="seen"] #intro-screen { display: none; }
html[data-intro="pending"] body { overflow: hidden; }

.intro-screen:focus,
.intro-screen:focus-visible { outline: none; box-shadow: none; }

/* skip / simple fade — jumps to the end state in <400ms */
.intro-screen.intro-skipping { opacity: 0; pointer-events: none; }

/* reveal: the overlay itself goes clear, the doors are the cover */
.intro-screen[data-phase="reveal"] { background: transparent; }

/* ---- layer 1: "power on" dim over the hero area ---- */
.intro-power {
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--ink);
  opacity: 0.6;
  pointer-events: none;
}
.intro-screen[data-phase="reveal"] .intro-power {
  opacity: 0;
  transition: opacity 950ms var(--ease-mech) 480ms; /* dark -> normal */
}

/* ---- layer 3: stepped green glow vignette (no smooth radial) ---- */
.intro-vignette {
  position: absolute;
  inset: 0;
  z-index: 3;
  opacity: 0.28;
  pointer-events: none;
  background:
    radial-gradient(closest-side at 50% 44%, var(--glow-soft) 0 12%, transparent 12%),
    radial-gradient(closest-side at 50% 44%, var(--glow-soft) 0 24%, transparent 24%),
    radial-gradient(closest-side at 50% 44%, var(--glow-soft) 0 36%, transparent 36%),
    radial-gradient(closest-side at 50% 44%, var(--glow-soft) 0 48%, transparent 48%),
    radial-gradient(closest-side at 50% 44%, var(--glow-soft) 0 60%, transparent 60%);
}
.intro-screen[data-phase="reveal"] .intro-vignette {
  opacity: 0;
  transition: opacity 360ms var(--ease-mech) 220ms;
}

/* ---- layer 4: terminal lines + block cursor ---- */
.intro-term {
  position: absolute;
  inset: 0;
  z-index: 4;
  display: flex;
  flex-direction: column;
  justify-content: center;
  width: min(720px, 88vw);
  margin: 0 auto;
  pointer-events: none;
}
.intro-line {
  margin: 0 0 clamp(6px, 1.4vh, 12px);
  min-height: 1.3em;
  font-family: var(--font-term);
  font-size: clamp(18px, 2.6vw, 27px);
  letter-spacing: 1px;
  color: var(--terminal);
  text-shadow: 0 0 8px var(--glow-soft);
}
/* boot: the lone block cursor sits centred before typing begins */
.intro-screen[data-phase="boot"] .intro-line { text-align: center; }
.intro-line.glitched { animation: introLineGlitch 150ms steps(2, end) 1; }
@keyframes introLineGlitch {
  0%   { transform: translateX(3px);  text-shadow: -2px 0 0 var(--sol-cyan), 2px 0 0 var(--sol-purple); }
  50%  { transform: translateX(-3px); text-shadow: 2px 0 0 var(--sol-cyan), -2px 0 0 var(--sol-purple); }
  100% { transform: translateX(0);    text-shadow: 0 0 8px var(--glow-soft); }
}
.intro-screen[data-phase="reveal"] .intro-term {
  opacity: 0;
  transition: opacity 200ms var(--ease-mech) 160ms;
}

.intro-cursor {
  display: inline-block;
  width: 0.55em;
  height: 1em;
  margin-left: 6px;
  vertical-align: text-bottom;
  background: var(--terminal);
  box-shadow: 0 0 8px var(--glow-terminal);
  animation: introBlink 1s step-end infinite;
}
.intro-cursor.flash { animation: introCursorFlash 130ms step-end 4; }
@keyframes introBlink { 0%, 55% { opacity: 1; } 56%, 100% { opacity: 0.15; } }
@keyframes introCursorFlash { 0% { opacity: 1; } 50% { opacity: 0; } 100% { opacity: 1; } }

/* ---- layer 4: PRESS ENTER prompt ---- */
.intro-enter {
  position: absolute;
  left: 50%;
  top: calc(50% + clamp(120px, 22vh, 190px));
  transform: translateX(-50%);
  z-index: 4;
  -webkit-appearance: none;
  appearance: none;
  background: var(--ink-2);
  border: var(--px) solid var(--forest-2);
  box-shadow: 0 0 0 var(--px) var(--ink), 0 0 16px var(--glow-soft);
  color: var(--terminal);
  font-family: var(--font-pixel);
  font-size: clamp(9px, 1.7vw, 12px);
  letter-spacing: 1px;
  padding: 14px 18px;
  cursor: pointer;
  text-shadow: 0 0 8px var(--glow-soft);
}
.intro-enter[hidden] { display: none; }
.intro-enter:hover {
  color: var(--white-hi);
  border-color: var(--terminal);
  box-shadow: 0 0 0 var(--px) var(--ink), 0 0 22px var(--glow-terminal);
}
.intro-enter-blink { animation: introBlink 1.1s step-end infinite; }
.intro-enter.flash { background: var(--terminal); color: var(--ink); text-shadow: none; }
.intro-enter.flash .intro-enter-blink { animation: introCursorFlash 130ms step-end 4; }
.intro-screen[data-phase="reveal"] .intro-enter {
  opacity: 0;
  pointer-events: none;
  transition: opacity 240ms var(--ease-mech) 220ms;
}

/* ---- layer 5: light leaking through the widening gap ---- */
.intro-leak {
  position: absolute;
  top: 0;
  bottom: 0;
  left: 50%;
  width: 10px;
  margin-left: -5px;
  z-index: 5;
  visibility: hidden;
  pointer-events: none;
  background: linear-gradient(90deg,
    var(--sol-purple) 0 10%,
    var(--sol-cyan) 10% 28%,
    var(--terminal) 28% 44%,
    var(--white-hi) 44% 56%,
    var(--terminal) 56% 72%,
    var(--sol-cyan) 72% 90%,
    var(--sol-purple) 90% 100%);
}
.intro-screen[data-phase="reveal"] .intro-leak {
  visibility: visible;
  animation: introLeak 1400ms var(--ease-mech) 480ms 1 both;
}
@keyframes introLeak {
  0%   { transform: scaleX(0.2); opacity: 0; }
  10%  { transform: scaleX(1);   opacity: 0.85; }
  55%  { transform: scaleX(40);  opacity: 0.4; }
  100% { transform: scaleX(85);  opacity: 0; }
}

/* ---- layer 6: pixel vault doors + camera push ---- */
.intro-doors {
  position: absolute;
  inset: 0;
  z-index: 6;
  visibility: hidden;
  pointer-events: none;
}
.intro-screen[data-phase="reveal"] .intro-doors {
  visibility: visible;
  animation: introPush 1400ms var(--ease-mech) 480ms 1 both; /* forward camera push */
}
.intro-door {
  position: absolute;
  top: 0;
  bottom: 0;
  width: 50.5%;
  background:
    repeating-linear-gradient(0deg, transparent 0 44px, var(--scanline) 44px 48px),
    linear-gradient(180deg, var(--charcoal) 0 26%, var(--ink-3) 26% 62%, var(--ink-2) 62% 100%);
}
.intro-door::before { /* vertical plating columns */
  content: '';
  position: absolute;
  inset: 0;
  background: repeating-linear-gradient(90deg, transparent 0 34px, var(--scanline) 34px 38px);
}
.intro-door::after { /* hazard stripe beside the seam */
  content: '';
  position: absolute;
  top: 0;
  bottom: 0;
  width: 16px;
  background: repeating-linear-gradient(45deg, var(--amber) 0 10px, var(--ink-2) 10px 20px);
  opacity: 0.85;
}
.intro-door-l {
  left: 0;
  border-right: calc(2 * var(--px)) solid var(--forest-2);
  box-shadow: inset calc(-4 * var(--px)) 0 0 var(--ink), inset calc(-7 * var(--px)) 0 0 var(--forest);
}
.intro-door-l::after { right: 18px; }
.intro-door-r {
  right: 0;
  border-left: calc(2 * var(--px)) solid var(--forest-2);
  box-shadow: inset calc(4 * var(--px)) 0 0 var(--ink), inset calc(7 * var(--px)) 0 0 var(--forest);
}
.intro-door-r::after { left: 18px; }
.intro-screen[data-phase="reveal"] .intro-door-l { animation: introDoorL 1150ms steps(14, end) 480ms 1 both; }
.intro-screen[data-phase="reveal"] .intro-door-r { animation: introDoorR 1150ms steps(14, end) 480ms 1 both; }
@keyframes introDoorL {
  0%   { transform: translateX(0); }
  9%   { transform: translateX(1.4%); }   /* mechanical clench inward */
  100% { transform: translateX(-106%); }
}
@keyframes introDoorR {
  0%   { transform: translateX(0); }
  9%   { transform: translateX(-1.4%); }
  100% { transform: translateX(106%); }
}
@keyframes introPush {
  0%   { transform: scale(1);    opacity: 1; }
  55%  { transform: scale(1.05); opacity: 1; }
  100% { transform: scale(1.16); opacity: 0; }
}

/* ---- layer 7: tiny noise/glitch canvas ---- */
.intro-noise {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  z-index: 7;
  opacity: 0.12;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
  pointer-events: none;
}
.intro-screen[data-phase="reveal"] .intro-noise { animation: introNoiseBurst 640ms steps(7, end) 1 both; }
@keyframes introNoiseBurst {
  0%   { opacity: 0.34; }
  45%  { opacity: 0.3; }
  100% { opacity: 0; }
}

/* ---- layer 8: bright horizontal scan sweep ---- */
.intro-scan {
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  height: 6px;
  z-index: 8;
  opacity: 0;
  pointer-events: none;
  background: linear-gradient(180deg, var(--white-hi), var(--terminal));
  box-shadow: 0 0 18px var(--glow-terminal), 0 0 40px var(--glow-soft);
}
.intro-screen[data-phase="reveal"] .intro-scan { animation: introScan 520ms steps(22, end) 40ms 1 both; }
@keyframes introScan {
  0%   { transform: translateY(-8px); opacity: 1; }
  90%  { opacity: 1; }
  100% { transform: translateY(100vh); opacity: 0; }
}

/* ---- layer 9: CATBACK wordmark flash ---- */
.intro-wordmark {
  position: absolute;
  inset: 0;
  z-index: 9;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: clamp(12px, 2.4vw, 22px);
  visibility: hidden;
  pointer-events: none;
}
.intro-wordmark img {
  width: clamp(40px, 7vw, 64px);
  height: auto;
  image-rendering: pixelated;
  image-rendering: crisp-edges;
}
.intro-wordmark-text {
  font-family: var(--font-pixel);
  font-size: clamp(24px, 6vw, 46px);
  color: var(--white-hi);
  letter-spacing: 4px;
  text-shadow:
    0 0 18px var(--glow-terminal),
    -3px 0 0 var(--sol-cyan),
    3px 0 0 var(--sol-purple),
    4px 4px 0 var(--forest);
}
.intro-screen[data-phase="reveal"] .intro-wordmark {
  visibility: visible;
  animation: introWordmark 900ms var(--ease-snap) 700ms 1 both;
}
@keyframes introWordmark {
  0%   { opacity: 0; transform: scale(0.86); }
  14%  { opacity: 1; transform: scale(1); }
  70%  { opacity: 1; transform: scale(1.03); }
  100% { opacity: 0; transform: scale(1.08); }
}

/* ---- layer 10: SKIP INTRO ---- */
.intro-skip {
  position: absolute;
  top: 12px;
  right: 12px;
  z-index: 10;
  -webkit-appearance: none;
  appearance: none;
  background: var(--ink-2);
  border: var(--px) solid var(--forest-2);
  color: var(--terminal-soft);
  font-family: var(--font-pixel);
  font-size: 8px;
  letter-spacing: 1px;
  padding: 9px 11px;
  cursor: pointer;
  transition: color var(--dur-fast) var(--ease-snap), border-color var(--dur-fast) var(--ease-snap);
}
.intro-skip:hover { color: var(--white-hi); border-color: var(--terminal); }