/* The landing page's stylesheet (docs/trd/08-frontend.md §4.25). Moved out of the page's inline
   <style> so the strict CSP can allow it; the rules below the fonts are the page's own, unchanged
   except for the two classes at the end that replace its style="" attributes. The fonts are the
   vendored ones (Google Fonts is no longer used): see /vendor/fonts/87ae5c63/CREDITS.txt. */
@font-face { font-family: 'Press Start 2P'; font-style: normal; font-weight: 400; font-display: swap; src: url(/vendor/fonts/87ae5c63/press-start-2p-latin.woff2) format('woff2'); }
@font-face { font-family: 'VT323'; font-style: normal; font-weight: 400; font-display: swap; src: url(/vendor/fonts/87ae5c63/vt323-latin.woff2) format('woff2'); }

:root {
  --black: #000000; --blue: #0000AA; --green: #00AA00; --cyan: #00AAAA;
  --red: #AA0000; --magenta: #AA00AA; --brown: #AA5500; --lightgray: #AAAAAA;
  --darkgray: #555555; --lightblue: #5555FF; --lightgreen: #55FF55; --lightcyan: #55FFFF;
  --lightred: #FF5555; --lightmagenta: #FF55FF; --yellow: #FFFF55; --white: #FFFFFF;
  --pixel: 'Press Start 2P', monospace;
  --term: 'VT323', monospace;
}
* { box-sizing: border-box; }
html { scroll-behavior: smooth; }
body {
  margin: 0; padding: 16px; background: var(--black); color: var(--white);
  font-family: var(--term); font-size: 22px; line-height: 1.25;
  -webkit-font-smoothing: none;
}
::selection { background: var(--yellow); color: var(--black); }
[id] { scroll-margin-top: 90px; }
.sr { position: absolute; width: 1px; height: 1px; margin: -1px; overflow: hidden; clip: rect(0 0 0 0); white-space: nowrap; }

/* ---------- CRT screen ---------- */
.screen {
  position: relative; max-width: 1280px; margin: 0 auto;
  background: var(--blue); border-radius: 28px;
  overflow: hidden; overflow: clip;
  box-shadow: inset 0 0 160px rgba(0,0,0,.55), 0 0 0 3px var(--darkgray);
}
.screen::after { /* scanlines */
  content: ""; position: absolute; inset: 0; z-index: 50; pointer-events: none;
  border-radius: inherit;
  background: repeating-linear-gradient(to bottom, rgba(0,0,0,0) 0 2px, rgba(0,0,0,.12) 2px 3px);
}
.bezel {
  max-width: 1280px; margin: 10px auto 0; padding: 0 28px;
  display: flex; justify-content: flex-end; align-items: center; gap: 10px;
  font: 8px var(--pixel); color: var(--darkgray);
}
.led { width: 8px; height: 8px; background: var(--lightgreen); box-shadow: 0 0 6px var(--lightgreen); }

/* ---------- HUD ---------- */
.hud {
  position: sticky; top: 0; z-index: 40;
  display: flex; align-items: center; flex-wrap: wrap; gap: 10px 22px;
  padding: 12px 24px; background: var(--black);
  border-bottom: 4px solid var(--lightcyan);
  font: 10px var(--pixel);
}
.hud-logo {
  color: var(--yellow); font-size: 12px; text-decoration: none; white-space: nowrap;
  text-shadow: 2px 2px 0 var(--magenta);
}
.hud-stats { display: flex; align-items: center; gap: 22px; margin: 0 auto; color: var(--lightgray); }
.stat { display: inline-flex; align-items: center; gap: 8px; white-space: nowrap; }
.stat b { color: var(--lightred); font-weight: normal; }
.meter { display: inline-flex; gap: 2px; }
.meter i { width: 8px; height: 12px; background: var(--darkgray); }
.meter i.on { background: var(--lightgreen); }
.heart { width: 14px; height: 12px; fill: var(--lightred); shape-rendering: crispEdges; }
.hud-nav { display: flex; align-items: center; gap: 6px; }
.hud-nav a { color: var(--white); text-decoration: none; padding: 8px 10px; border: 2px solid transparent; white-space: nowrap; }
.hud-nav a:hover { color: var(--yellow); border-color: var(--yellow); }
.hud-nav a:focus-visible { outline: 3px dashed var(--white); outline-offset: 2px; }
.hud-nav .btn-mini {
  color: var(--black); background: var(--yellow); border: 2px solid var(--black);
  box-shadow: inset 0 2px 0 var(--white), 0 4px 0 var(--brown);
  transition: transform 60ms linear, box-shadow 60ms linear;
}
.hud-nav .btn-mini:hover { color: var(--black); border-color: var(--black); transform: translateY(-1px); box-shadow: inset 0 2px 0 var(--white), 0 5px 0 var(--brown); }
.hud-nav .btn-mini:active { transform: translateY(4px); box-shadow: inset 0 2px 0 var(--brown), 0 0 0 var(--brown); }

/* ---------- Buttons ---------- */
.btn {
  --face: var(--yellow); --hi: var(--white); --lo: var(--brown); --drop: 8px;
  display: inline-flex; flex-direction: column; align-items: center; justify-content: center; gap: 10px;
  font: 15px/1.2 var(--pixel); color: var(--black); background: var(--face);
  text-decoration: none; text-transform: uppercase; cursor: pointer;
  border: 4px solid var(--black); border-radius: 0; padding: 18px 26px 16px;
  box-shadow: inset 0 4px 0 var(--hi), inset 0 -6px 0 var(--lo), 0 var(--drop) 0 var(--shadow, var(--black));
  transition: transform 60ms linear, box-shadow 60ms linear;
}
.btn:hover { color: var(--black); transform: translateY(-2px); box-shadow: inset 0 4px 0 var(--hi), inset 0 -6px 0 var(--lo), 0 calc(var(--drop) + 2px) 0 var(--shadow, var(--black)); }
.btn:active { transform: translateY(var(--drop)); box-shadow: inset 0 6px 0 var(--lo), inset 0 -2px 0 var(--hi), 0 0 0 var(--shadow, var(--black)); }
.btn:focus-visible { color: var(--black); outline: 4px dashed var(--white); outline-offset: 6px; }
.btn-secondary { --face: var(--lightcyan); --lo: var(--cyan); }
.btn-sub { font-size: 9px; letter-spacing: 1px; }

/* ---------- Hero (title screen) ---------- */
.hero {
  position: relative; text-align: center; padding: 40px 32px 52px;
  background-image:
    radial-gradient(circle, var(--white) 0 1px, transparent 1.6px),
    radial-gradient(circle, var(--lightcyan) 0 1px, transparent 1.6px),
    radial-gradient(circle, var(--lightmagenta) 0 1px, transparent 1.6px);
  background-size: 140px 110px, 220px 170px, 310px 240px;
  background-position: 10px 20px, 80px 60px, 150px 130px;
  animation: drift 60s linear infinite;
}
@keyframes drift { to { background-position: 10px 1120px, 80px 1760px, 150px 2530px; } }
.kicker { font: 11px/1.9 var(--pixel); color: var(--lightgreen); letter-spacing: 2px; margin: 0 0 16px; }
/* Static on purpose: nothing above the fold waits on an animation. */
.title-logo { margin: 0 0 24px; }
.title-logo .big {
  display: block; font: clamp(48px, 11vw, 108px)/1 var(--pixel); color: var(--yellow);
  text-shadow: .03em .03em 0 var(--lightred), .06em .06em 0 var(--magenta), .09em .09em 0 var(--black);
}
.title-logo .small {
  display: block; margin-top: .5em; font: clamp(18px, 4.6vw, 40px)/1 var(--pixel); color: var(--lightcyan);
  letter-spacing: .08em; text-shadow: .1em .1em 0 var(--black);
}
.hero h1 {
  max-width: 920px; margin: 0 auto 18px; font: clamp(15px, 2.4vw, 24px)/1.6 var(--pixel);
  color: var(--white); text-shadow: 3px 3px 0 var(--black);
}
.hl { color: var(--yellow); }
.sub { max-width: 700px; margin: 0 auto 30px; font-size: 25px; color: var(--white); }
.hero-actions { display: flex; justify-content: center; align-items: center; flex-wrap: wrap; gap: 24px; }
.btn-start { font-size: 18px; padding: 20px 32px 18px; }
.blink { animation: blink 1.1s infinite; }
.blink-soft { animation: blink-soft 1.1s infinite; }
@keyframes blink { 0%, 49% { opacity: 1; } 50%, 100% { opacity: 0; } }
@keyframes blink-soft { 0%, 49% { opacity: 1; } 50%, 100% { opacity: .25; } }

/* ---------- Sections ---------- */
.divider { height: 8px; margin: 0 32px; background: repeating-linear-gradient(90deg, var(--lightblue) 0 8px, transparent 8px 16px); }
.section { max-width: 1140px; margin: 0 auto; padding: 64px 32px; }
.section-kicker { margin: 0 0 12px; font: 10px/1.6 var(--pixel); color: var(--lightgreen); letter-spacing: 2px; }
.section-title { margin: 0 0 14px; font: clamp(18px, 3vw, 28px)/1.4 var(--pixel); color: var(--yellow); text-shadow: 3px 3px 0 var(--black); }
.lede { margin: 0; font-size: 25px; color: var(--lightcyan); }

/* ---------- The problems (stage select) ---------- */
.worlds { display: grid; grid-template-columns: 1fr 1fr; gap: 40px; margin-top: 36px; }
.world-head { display: flex; align-items: center; flex-wrap: wrap; gap: 12px; }
.world-tag { font: 10px var(--pixel); color: var(--black); background: var(--yellow); padding: 6px 8px; }
.world-2 .world-tag { background: var(--lightgreen); }
.world h3 { margin: 0; font: 15px/1.5 var(--pixel); color: var(--white); }
.world-desc { margin: 12px 0 0; color: var(--lightgray); }
.stages { list-style: none; margin: 20px 0 0; padding: 0; display: grid; gap: 20px; }
.stage {
  position: relative; color: var(--white);
  background: var(--black); border: 3px solid var(--lightcyan);
  box-shadow: 6px 6px 0 var(--black); padding: 14px 16px 16px;
  transition: transform 80ms steps(2), box-shadow 80ms steps(2), border-color 80ms;
}
.stage:hover, .stage:focus-within { transform: translate(-3px, -3px); box-shadow: 9px 9px 0 var(--black); border-color: var(--yellow); }
.stage:active { transform: translate(6px, 6px); box-shadow: 0 0 0 var(--black); }
.stage.boss-stage { border-color: var(--lightred); }
.stage.boss-stage:hover, .stage.boss-stage:focus-within { border-color: var(--yellow); }
.stage-top { display: flex; align-items: center; flex-wrap: wrap; gap: 8px 10px; margin-bottom: 12px; }
.cursor { width: 12px; font: 12px var(--pixel); color: var(--yellow); visibility: hidden; }
.stage:hover .cursor, .stage:focus-within .cursor { visibility: visible; animation: blink .8s infinite; }
.stage-num { font: 11px var(--pixel); color: var(--black); background: var(--yellow); padding: 5px 7px; }
.world-2 .stage-num { background: var(--lightgreen); }
.stage.boss-stage .stage-num { background: var(--lightred); }
.kind { font: 8px/1.4 var(--pixel); color: var(--lightgray); }
.diff { margin-left: auto; display: inline-flex; align-items: center; gap: 8px; font: 9px var(--pixel); }
.diff-meter { display: inline-flex; gap: 3px; }
.diff-meter i { width: 10px; height: 12px; background: var(--darkgray); }
.diff-easy { color: var(--lightgreen); }
.diff-easy .diff-meter i:first-child { background: var(--lightgreen); }
.diff-medium { color: var(--yellow); }
.diff-medium .diff-meter i:nth-child(-n+2) { background: var(--yellow); }
.diff-hard { color: var(--lightred); }
.diff-hard .diff-meter i { background: var(--lightred); }
.diff-nightmare { color: var(--white); background: var(--magenta); padding: 3px 4px; }
.diff-nightmare .diff-meter i { background: var(--black); }
.stage-name { margin: 0; font: 15px/1.5 var(--pixel); color: var(--white); text-shadow: 2px 2px 0 var(--blue); }
.stage:hover .stage-name, .stage:focus-within .stage-name { color: var(--yellow); }
.stage-text { margin: 8px 0 0; font-size: 23px; line-height: 1.2; color: var(--white); }
.specs { display: grid; grid-template-columns: max-content minmax(0, 1fr); gap: 8px 14px; align-items: center; margin: 14px 0 0; padding-top: 12px; border-top: 2px dashed var(--darkgray); }
.specs div { display: contents; }
.specs dt { font: 9px var(--pixel); color: var(--lightcyan); }
.specs dd { margin: 0; }
.specs .mem dt { color: var(--yellow); }
.specs .mem dd span {
  display: inline-block; font: 14px/1 var(--pixel); color: var(--black); background: var(--yellow);
  padding: 6px 8px 5px; box-shadow: 3px 3px 0 var(--brown);
}
.specs .twist dt { color: var(--lightred); }
.specs .cpu dt { color: var(--lightmagenta); }
.pick {
  display: inline-block; margin-top: 14px; font: 10px/1.4 var(--pixel); color: var(--lightcyan);
  text-decoration: none;
}
.pick::after { content: ""; position: absolute; inset: 0; } /* the whole tile is the link */
.pick:focus-visible { outline: none; }
.pick:focus-visible::after { outline: 3px dashed var(--white); outline-offset: 6px; }
.stage:hover .pick, .stage:focus-within .pick { color: var(--yellow); }
.footnote { margin: 30px 0 0; font-size: 21px; color: var(--lightgray); }
.more {
  display: flex; flex-direction: column; align-items: center; gap: 10px 24px; margin-top: 28px; text-align: center;
  padding: 16px 20px; background: var(--black); border: 3px dashed var(--lightmagenta);
}
.more h3 { margin: 0; font: 12px/1.6 var(--pixel); color: var(--lightmagenta); }
.suggest { width: 100%; }
.suggest .btn { font-size: 11px; padding: 12px 16px 10px; border-width: 3px; --drop: 5px; }
.suggest summary { display: inline-flex; list-style: none; }
.suggest .form-error { margin: 0; }
.suggest summary::-webkit-details-marker { display: none; }
.suggest form { max-width: 560px; margin: 22px auto 0; gap: 16px; text-align: left; }
.suggest-done { margin: 18px 0 0; color: var(--lightgreen); outline: none; }
/* A loading bar whose blocks light up in turn; at rest (or with reduced motion) it stays grey. */
.loading { display: inline-flex; gap: 3px; margin-right: 12px; vertical-align: -1px; }
.loading i { width: 8px; height: 12px; background: var(--darkgray); animation: load 1.5s steps(1) infinite; }
.loading i:nth-child(2) { animation-delay: .15s; }
.loading i:nth-child(3) { animation-delay: .3s; }
.loading i:nth-child(4) { animation-delay: .45s; }
.loading i:nth-child(5) { animation-delay: .6s; }
@keyframes load { 0% { background: var(--lightmagenta); } 60% { background: var(--darkgray); } }

/* Power-on reveal: armed by JS only when motion is OK; tiles stay on once played. */
.reveal-armed .stage:not(.on) { opacity: 0; }
.reveal-armed .stage.on { animation: power-on .28s steps(4) backwards; }
@keyframes power-on {
  0%   { clip-path: inset(47% 0 47% 0); filter: brightness(3); }
  60%  { clip-path: inset(0); filter: brightness(1.8); }
  100% { clip-path: inset(0); filter: none; }
}

/* ---------- How to play + hi-scores ---------- */
.how-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 56px; align-items: start; }
.steps { list-style: none; margin: 28px 0 0; padding: 0; display: grid; gap: 22px; }
.steps li { display: grid; grid-template-columns: 56px 1fr; gap: 18px; align-items: center; padding-bottom: 20px; border-bottom: 3px dashed var(--lightblue); }
.steps li:last-child { border-bottom: 0; padding-bottom: 0; }
.key {
  width: 50px; height: 50px; border-radius: 50%; display: grid; place-items: center;
  font: 16px var(--pixel); color: var(--black); border: 3px solid var(--black);
  box-shadow: inset 0 4px 0 var(--white), 0 5px 0 var(--black);
}
.k1 { background: var(--lightred); } .k2 { background: var(--yellow); }
.k3 { background: var(--lightgreen); } .k4 { background: var(--lightcyan); }
.steps strong { display: block; margin-bottom: 6px; font: 12px var(--pixel); color: var(--yellow); }
.steps p { margin: 0; }
.scores { background: var(--black); border: 4px solid var(--lightcyan); box-shadow: 10px 10px 0 var(--black); padding: 22px; }
.scores table { width: 100%; border-collapse: collapse; font: 12px var(--pixel); }
.scores caption { text-align: left; margin-bottom: 16px; font-size: 16px; color: var(--yellow); }
.tag { display: inline-block; vertical-align: middle; margin-left: 10px; padding: 4px 6px; font-size: 8px; color: var(--black); background: var(--lightmagenta); }
.scores th { padding: 0 6px 12px; text-align: left; font-size: 9px; font-weight: normal; color: var(--lightgray); }
.scores td { padding: 9px 6px; }
.scores .mem { text-align: right; }
.scores tbody tr:nth-child(1) { color: var(--yellow); }
.scores tbody tr:nth-child(2) { color: var(--lightcyan); }
.scores tbody tr:nth-child(3) { color: var(--lightgreen); }
.scores tbody tr:nth-child(4) { color: var(--lightmagenta); }
.scores tbody tr:nth-child(5) { color: var(--white); }
.scores tbody tr:nth-child(6) { color: var(--lightgray); }
.scores tr.you { color: var(--yellow); background: var(--blue); }
.scores-note { margin: 16px 0 0; color: var(--white); }

/* ---------- Join form ---------- */
.join-card {
  --shadow: var(--darkgray);
  max-width: 780px; margin: 0 auto; padding: 32px;
  background: var(--black); border: 4px solid var(--lightmagenta); box-shadow: 10px 10px 0 var(--black);
}
.p1 { margin: 0 0 16px; font: 10px var(--pixel); color: var(--lightgreen); letter-spacing: 1px; }
.join-card > p.intro { margin: 0 0 30px; }
form { display: grid; gap: 28px; }
form[hidden], .success[hidden] { display: none; }
.field label, .field legend { display: block; margin-bottom: 12px; padding: 0; font: 11px/1.6 var(--pixel); color: var(--lightcyan); }
fieldset { margin: 0; padding: 0; border: 0; min-width: 0; }
input[type="email"], select, textarea {
  width: 100%; padding: 10px 14px; border-radius: 0; outline: none;
  font: 26px var(--term); color: var(--white); background: var(--blue);
  border: 3px solid var(--lightcyan); caret-color: var(--yellow);
}
input::placeholder { color: var(--lightgray); }
textarea { min-height: 120px; resize: vertical; }
input[type="email"]:focus-visible, select:focus-visible, textarea:focus-visible { border-color: var(--yellow); outline: 3px dashed var(--yellow); outline-offset: 3px; }
input[aria-invalid="true"] { border-color: var(--lightred); }
.select-wrap { position: relative; }
.select-wrap::after { content: "▼"; position: absolute; right: 14px; top: 50%; transform: translateY(-50%); color: var(--yellow); pointer-events: none; font-size: 18px; }
select { appearance: none; -webkit-appearance: none; padding-right: 44px; cursor: pointer; }
select option, select optgroup { background: var(--black); color: var(--white); }
select.picked { animation: picked .5s steps(1) 2; }
@keyframes picked { 0% { border-color: var(--yellow); } 50% { border-color: var(--lightmagenta); } }
.lang-grid { display: grid; grid-template-columns: repeat(4, 1fr); gap: 14px; }
.lang { position: relative; display: block; cursor: pointer; }
.lang input { position: absolute; inset: 0; width: 100%; height: 100%; margin: 0; opacity: 0; cursor: pointer; }
.lang span {
  position: relative; display: block; padding: 16px 8px; text-align: center;
  font: 13px var(--pixel); color: var(--white); background: var(--blue);
  border: 3px solid var(--lightcyan); box-shadow: 0 6px 0 var(--darkgray);
  transition: transform 60ms linear, box-shadow 60ms linear;
}
.lang:hover span { border-color: var(--yellow); }
.lang input:checked + span { color: var(--black); background: var(--yellow); border-color: var(--black); transform: translateY(6px); box-shadow: 0 0 0 var(--darkgray); }
.lang input:checked + span::after { content: "P1"; position: absolute; top: -12px; right: -8px; padding: 4px; font-size: 8px; color: var(--black); background: var(--lightred); border: 2px solid var(--black); }
.lang input:focus-visible + span { outline: 4px dashed var(--white); outline-offset: 4px; }
.form-error { min-height: 1em; margin: -10px 0 0; font: 10px/1.6 var(--pixel); color: var(--lightred); }
.btn:disabled { cursor: progress; }
.btn[aria-busy="true"] > span:first-child { animation: blink-soft 1.1s infinite; }
.form-foot { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 20px; }
.coin { font: 11px var(--pixel); color: var(--yellow); }
.success { text-align: center; padding: 20px 0 8px; outline: none; }
.ready { margin: 0 0 22px; font: clamp(18px, 4vw, 30px)/1.4 var(--pixel); color: var(--lightgreen); text-shadow: 3px 3px 0 var(--green); }
.success p { margin: 0 0 22px; }
.success b { color: var(--yellow); font-weight: normal; word-break: break-all; }
.ready-stats { display: inline-grid; gap: 10px; margin: 0; text-align: left; }
.ready-stats div { display: flex; flex-wrap: wrap; gap: 6px 14px; align-items: baseline; }
.ready-stats dt { font: 10px var(--pixel); color: var(--lightcyan); }
.ready-stats dd { margin: 0; }

/* ---------- Footer ---------- */
.foot {
  display: flex; justify-content: space-between; align-items: center; flex-wrap: wrap; gap: 12px 24px;
  padding: 22px 32px 28px; background: var(--black); border-top: 4px solid var(--lightcyan);
  font: 10px/1.6 var(--pixel); color: var(--lightgray);
}
.credits { color: var(--yellow); }
.foot-links { display: flex; gap: 8px; margin: -8px 0; }
.foot-links a { color: var(--white); text-decoration: none; padding: 8px 10px; border: 2px solid var(--darkgray); }
.foot-links a:hover { color: var(--yellow); border-color: var(--yellow); }
.foot-links a:focus-visible { outline: 3px dashed var(--white); outline-offset: 2px; }

/* ---------- Responsive ---------- */
@media (max-width: 900px) {
  .worlds, .how-grid { grid-template-columns: 1fr; }
  .how-grid { gap: 48px; }
}
@media (max-width: 760px) {
  body { padding: 6px; }
  .screen { border-radius: 16px; }
  .hud { padding: 10px 12px; gap: 10px 12px; font-size: 9px; }
  .hud-stats { margin: 0 0 0 auto; }
  .stat.cpu, .stat.crashes { display: none; }
  .hud-nav { order: 3; width: 100%; justify-content: space-between; gap: 4px; }
  .hud-nav a { padding: 7px 6px; }
  .hero { padding: 32px 16px 40px; }
  .sub { font-size: 23px; }
  .divider { margin: 0 16px; }
  .section { padding: 48px 16px; }
  .stage { padding: 12px 12px 14px; }
  .stage-name { font-size: 13px; }
  .join-card { padding: 22px 16px; }
  .lang-grid { grid-template-columns: repeat(2, 1fr); }
  .foot { padding: 20px 16px 24px; }
}
@media (max-width: 520px) {
  .hero-actions { flex-direction: column; align-items: stretch; }
  .btn-start { font-size: 15px; }
  .specs .mem dd span { font-size: 12px; }
  .scores { padding: 16px 12px; }
  .scores table { font-size: 10px; }
  .form-foot .btn { width: 100%; }
}
@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { animation: none !important; transition: none !important; }
}
/* ---------- Classes that replace the two style="" attributes (the CSP forbids those) ---------- */
.sprite { position: absolute; }
.honeypot { display: none; }