:root {
  --sky: #0b95d3;           /* swapped at random on every page load (game.js) */
  --ink: #141414;
  --paper: #ffffff;
  --muted: #4a4a4a;
  --calm-red: #ff0000;
  --calm-yellow: #ffe500;
  --calm-green: #00c000;
  --col: min(100vw, 560px);
  --gutter: 16px;
  --display: 'Anton', Impact, 'Arial Narrow Bold', sans-serif;
  --body: 'Inter', system-ui, -apple-system, sans-serif;
}

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

/* Size the page to the *large* viewport so on iPhone the sky runs on behind
   Safari's floating toolbars instead of stopping at a grey band (bottomless look) */
html, body {
  height: 100vh;
  height: 100lvh;
  overflow: hidden;
  overscroll-behavior: none;
}

/* iPhone Safari tints its toolbars from the page background, so match the sky at the top */
html { background-color: var(--sky); }

body {
  position: relative; /* overlays below anchor to the full-height page, not the screen */
  background: #fff linear-gradient(180deg, var(--sky) 0%, var(--sky) 32%, #fff 100%) no-repeat;
  background-size: 100% 100%;
  color: var(--paper);
  font-family: var(--body);
  -webkit-user-select: none;
  user-select: none;
  -webkit-tap-highlight-color: transparent;
  -webkit-touch-callout: none;
}

canvas#game {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100vh;
  height: 100lvh;
  touch-action: none;
  cursor: grab;
}
canvas#game.grabbing { cursor: grabbing; }

/* ---------- HUD ---------- */
/* Overlays use position:absolute, not fixed: iPhone Safari colours its toolbars from fixed
   layers touching the screen edges, and transparent ones turn them grey. The page never
   scrolls, so absolute looks the same. */
.hud {
  position: absolute;
  top: calc(env(safe-area-inset-top) + 14px);
  left: 50%;
  transform: translateX(-50%);
  width: var(--col);
  padding: 0 var(--gutter);
  display: flex;
  justify-content: space-between;
  align-items: center;
  pointer-events: none;
  z-index: 10;
}
.hud > * { pointer-events: auto; }

.hud-btn {
  width: 44px;
  height: 44px;
  border: 3px solid var(--paper);
  background: transparent;
  color: var(--paper);
  font: 26px/1 var(--display);
  cursor: pointer;
  box-shadow: 2px 3px 6px rgb(0 0 0 / .18);
  text-shadow: 0 1px 2px rgb(0 0 0 / .25);
  transition: transform .12s ease, background-color .12s ease;
}
.hud-btn:hover { background: rgb(255 255 255 / .14); }
.hud-btn:active { transform: scale(.94); }


.meter {
  position: relative;
  width: min(52vw, 236px);
  height: 40px;
  border: 3px solid var(--paper);
  padding: 3px;
  box-shadow: 2px 3px 6px rgb(0 0 0 / .18);
  overflow: hidden;
}
.meter-fill {
  height: 100%;
  width: 100%;
  transform-origin: left center;
  transform: scaleX(.12);
  background: var(--calm-red);
  transition: transform .35s cubic-bezier(.2, .9, .3, 1.2), background-color .25s ease;
}
.meter-fill.is-yellow { background: var(--calm-yellow); }
.meter-fill.is-green  { background: var(--calm-green); }
.meter-flash {
  position: absolute;
  inset: 0;
  background: var(--calm-red);
  opacity: 0;
}
.meter-label {
  position: absolute;
  inset: 0;
  display: grid;
  place-items: center;
  font: 24px/1 var(--display);
  letter-spacing: .02em;
  color: var(--paper);
  text-shadow: 0 1px 0 rgb(0 0 0 / .35), 0 0 6px rgb(0 0 0 / .2);
}

/* Hit: the bar flashes full red twice (in sync with the object) and shakes */
.meter.is-hit .meter-flash { animation: flash-twice .6s linear; }
.meter.is-hit { animation: shake .45s cubic-bezier(.36, .07, .19, .97); }

@keyframes flash-twice {
  0%, 25%  { opacity: 1; }
  25.01%, 42% { opacity: 0; }
  42.01%, 75% { opacity: 1; }
  75.01%, 100% { opacity: 0; }
}
@keyframes shake {
  10%, 90% { translate: -2px 0; }
  20%, 80% { translate: 4px 0; }
  30%, 50%, 70% { translate: -7px 0; }
  40%, 60% { translate: 7px 0; }
}

/* Level clear: a short glow on the full bar */
.meter.is-full { animation: glow 1s ease-out; }
@keyframes glow {
  0% { box-shadow: 0 0 0 0 rgb(255 255 255 / .9); }
  100% { box-shadow: 0 0 0 18px rgb(255 255 255 / 0); }
}

/* ---------- Announcements ---------- */
.banner {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 100vh;
  height: 100svh; /* centre in the part of the screen toolbars never cover */
  display: grid;
  place-content: center;
  justify-items: center;
  gap: 6px;
  pointer-events: none;
  z-index: 20;
  text-align: center;
}
.banner-main {
  font: clamp(64px, 22vw, 150px)/.95 var(--display);
  color: var(--paper);
  -webkit-text-stroke: 4px var(--ink);
  paint-order: stroke fill;
  text-shadow: 0 8px 0 var(--ink);
  text-transform: uppercase;
  opacity: 0;
}
.banner-main.is-count { font-size: clamp(110px, 40vw, 240px); }
.banner-main.is-go { color: var(--calm-green); }
.banner-main.is-calm { color: var(--calm-yellow); font-size: clamp(56px, 18vw, 130px); }
.banner-sub {
  font: 700 18px/1.3 var(--body);
  color: var(--ink);
  background: var(--paper);
  padding: 6px 14px;
  opacity: 0;
}
.banner.is-on .banner-main { animation: pop .55s cubic-bezier(.2, 1.4, .4, 1) forwards; }
.banner.is-on .banner-sub:not(:empty) { animation: rise .4s .15s ease-out forwards; }
.banner.is-off .banner-main,
.banner.is-off .banner-sub { animation: out .2s ease-in forwards; }

@keyframes pop {
  0% { opacity: 0; transform: scale(.3) rotate(-8deg); }
  60% { opacity: 1; transform: scale(1.12) rotate(2deg); }
  100% { opacity: 1; transform: scale(1) rotate(0); }
}
@keyframes rise {
  from { opacity: 0; transform: translateY(10px); }
  to { opacity: 1; transform: none; }
}
@keyframes out {
  from { opacity: 1; }
  to { opacity: 0; transform: scale(1.15); }
}

/* ---------- Start / win screens ---------- */
.screen {
  position: absolute;
  inset: 0;
  z-index: 30;
  display: grid;
  place-items: center;
  padding: var(--gutter);
  padding-bottom: calc(var(--gutter) + (100lvh - 100svh)); /* dim runs under the toolbar, content stays above it */
  background: rgb(0 0 0 / .28);
}
.screen[hidden] { display: none; }
.screen:not([hidden]) {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 18px;
}

.disclaimer {
  width: min(100%, 400px);
  padding: 8px 12px;
  background: rgb(255 255 255 / .88);
  color: var(--muted);
  font-size: 12px;
  line-height: 1.45;
  text-align: center;
}

#winScreen .disclaimer {
  position: absolute;
  top: var(--disclaimer-top, auto);
  bottom: calc(env(safe-area-inset-bottom) + 24px);
  left: 50%;
  translate: -50% 0;
  width: min(calc(100vw - 2 * var(--gutter)), 400px);
  height: max-content;
}

.card {
  position: relative;
  width: min(100%, 400px);
  margin-top: 90px;
  padding: 96px 24px 24px;
  background: var(--paper);
  color: var(--ink);
  text-align: center;
  border: 4px solid var(--ink);
  box-shadow: 8px 8px 0 var(--ink);
  animation: rise .4s ease-out;
}
.card-hero {
  position: absolute;
  left: 50%;
  top: 0;
  translate: -50% -62%;
  width: auto;
  height: 190px;
  pointer-events: none;
}
.card h1, .card h2 {
  font: clamp(48px, 15vw, 68px)/.95 var(--display);
  text-transform: uppercase;
  color: var(--ink);
  text-shadow: 4px 4px 0 var(--sky);
  margin-bottom: 14px;
}
.card p {
  font-size: 17px;
  line-height: 1.5;
  color: var(--muted);
  margin-bottom: 22px;
}

.btn {
  display: block;
  width: 100%;
  min-height: 56px;
  border: 3px solid var(--ink);
  background: var(--sky);
  color: var(--paper);
  font: 28px/1 var(--display);
  text-transform: uppercase;
  letter-spacing: .03em;
  text-shadow: 0 2px 0 rgb(0 0 0 / .3);
  box-shadow: 4px 4px 0 var(--ink);
  cursor: pointer;
  transition: transform .1s ease, box-shadow .1s ease;
}
.btn:hover { transform: translate(-1px, -1px); box-shadow: 5px 5px 0 var(--ink); }
.btn:active { transform: translate(3px, 3px); box-shadow: 1px 1px 0 var(--ink); }

.link-btn {
  margin-top: 14px;
  min-height: 44px;
  padding: 0 12px;
  border: 0;
  background: none;
  font: 700 16px var(--body);
  color: var(--ink);
  text-decoration: underline;
  text-underline-offset: 3px;
  cursor: pointer;
}

:focus-visible {
  outline: 3px solid var(--ink);
  outline-offset: 3px;
  box-shadow: 0 0 0 6px var(--paper);
}

/* ---------- Help dialog ---------- */
.help {
  width: min(calc(100% - 32px), 420px);
  margin: auto;
  padding: 24px;
  border: 4px solid var(--ink);
  box-shadow: 8px 8px 0 var(--ink);
  background: var(--paper);
  color: var(--ink);
}
.help::backdrop { background: rgb(0 0 0 / .45); }
.help h2 {
  font: 40px/1 var(--display);
  text-transform: uppercase;
  margin-bottom: 14px;
}
.help ol {
  padding-left: 22px;
  margin-bottom: 22px;
  font-size: 16px;
  line-height: 1.5;
  color: var(--muted);
}
.help li + li { margin-top: 10px; }
.help strong { color: var(--ink); }

/* ---------- Utility ---------- */
.view-probe {
  position: absolute;
  top: 0;
  left: 0;
  width: 0;
  height: 100vh;
  height: 100svh; /* the part of the screen never covered by browser toolbars */
  visibility: hidden;
  pointer-events: none;
}
.safe-probe {
  position: absolute;
  visibility: hidden;
  padding-bottom: env(safe-area-inset-bottom);
  pointer-events: none;
}
.video-bin {
  position: absolute;
  left: 0;
  top: 0;
  width: 2px;
  height: 2px;
  overflow: hidden;
  opacity: 0;
  pointer-events: none;
}
.video-bin video { width: 2px; height: 2px; }

@media (prefers-reduced-motion: reduce) {
  .meter.is-hit { animation: none; }
  .banner.is-on .banner-main { animation: rise .2s ease-out forwards; }
  .meter-fill { transition-duration: .1s; }
}