@font-face { font-family: "VT323"; src: url("/fonts/vt323.ttf") format("truetype"); font-style: normal; font-weight: 400; font-display: swap; }
:root { color-scheme: dark; --sea: #060e1b; --panel: #111e32; --foam: #e5f3fb; --drift: #b1c3d8; --pink: #ff75ad; --cyan: #55e3f5; --line: #27384e; --pixel: "VT323", "Courier New", monospace; }
* { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 24px; }
body { margin: 0; background: var(--sea); color: var(--foam); font-family: Verdana, sans-serif; font-size: 15px; line-height: 1.85; }
a { color: inherit; text-underline-offset: 4px; }
a:hover { color: var(--cyan); }
button, a { -webkit-tap-highlight-color: transparent; }
button { font: inherit; cursor: pointer; }
button:focus-visible, a:focus-visible, summary:focus-visible { outline: 3px solid var(--pink); outline-offset: 5px; }
[hidden] { display: none !important; }
.skip-link { position: absolute; top: -100px; left: 16px; z-index: 10; padding: 10px; background: var(--sea); }
.skip-link:focus { top: 10px; }
.site-header { position: relative; z-index: 2; display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; min-height: 96px; padding: 14px max(24px, calc((100vw - 1120px) / 2)); border-bottom: 1px solid #526878; background: #101e2b; gap: 24px; }
.wordmark { flex-shrink: 0; font: 40px/1 var(--pixel); letter-spacing: 2px; text-decoration: none; white-space: nowrap; }
.wordmark span { display: block; margin-top: 4px; color: var(--pink); font-size: 30px; letter-spacing: 3px; }
.site-header nav { display: flex; flex-wrap: wrap; gap: 12px 24px; }
nav a { font: 19px var(--pixel); text-decoration: none; text-transform: uppercase; letter-spacing: 1px; padding: 8px 0; }
.hero { --surface: 330px; min-height: 720px; position: relative; isolation: isolate; overflow: hidden; text-align: center; background: linear-gradient(#80cbe6 0px, #c4edf6 var(--surface), #195a80 var(--surface), #0c3454 calc(var(--surface) + 140px), var(--sea) calc(var(--surface) + 280px)); }
.hero::after { content: ""; position: absolute; z-index: -1; inset: 0; pointer-events: none; background: repeating-linear-gradient(0deg, transparent 0 2px, #07132406 2px 3px); }
.ocean-surface { position: absolute; z-index: -2; inset: 0; background: url("/ocean.svg") center top / 1440px 620px no-repeat; }
.hero-content { width: min(900px, calc(100% - 40px)); margin: 0 auto; padding: 38px 0 35px; }
.eyebrow, .section-marker { font: 17px var(--pixel); letter-spacing: 2px; text-transform: uppercase; }
.hero-eyebrow { color: #344d61; margin: 0 0 5px; }
h1 { margin: 0; font: 112px/.97 var(--pixel); letter-spacing: 12px; color: #f0fbff; text-shadow: -4px 3px #f14f96, 4px -2px #35d5ed; }
#hero-title { font-size: clamp(72px, 12vw, 144px); letter-spacing: 0; }
.hero-word { display: flex; justify-content: center; gap: .07em; }
.hero-word > span { display: inline-block; animation: letter-wave 4.7s ease-in-out infinite; --crest: -.065em; --trough: .035em; }
.hero-word > span:nth-child(2) { animation-duration: 5.3s; animation-delay: -1.2s; --crest: -.09em; }
.hero-word > span:nth-child(3) { animation-duration: 4.3s; animation-delay: -2.1s; }
.hero-word > span:nth-child(4) { animation-duration: 5.9s; animation-delay: -2.8s; --trough: .055em; }
.hero-word > span:nth-child(5) { animation-duration: 5.1s; animation-delay: -3.4s; --crest: -.08em; }
.hero-word > span:nth-child(6) { animation-duration: 4.9s; animation-delay: -2.4s; }
.hero-word > span:nth-child(7) { animation-duration: 5.7s; animation-delay: -1.3s; --trough: .05em; }
.hero-word > span:nth-child(8) { animation-duration: 4.5s; animation-delay: -.6s; --crest: -.085em; }
.hero-subtitle { display: block; margin-top: 14px; font: 64px/1 var(--pixel); letter-spacing: .12em; text-indent: .12em; color: #244d5d; text-shadow: 2px 2px #bbf5ef; }
@keyframes letter-wave {
  0%, 100% { transform: translateY(var(--trough)) rotate(.7deg); }
  50% { transform: translateY(var(--crest)) rotate(-.7deg); }
}
.hero-tagline { color: #213d51; font: 29px var(--pixel); letter-spacing: 1px; margin: 19px 0 0; }
.hero-description { color: #dbeaf1; font: 23px/1.45 var(--pixel); margin: 47px 0 14px; letter-spacing: .3px; }
.krill { display: block; margin: 14px auto 19px; image-rendering: pixelated; animation: drift 5s ease-in-out infinite; }
.play-button { display: block; padding: 13px 16px; border: 2px solid var(--cyan); outline: 3px solid #71dce51c; outline-offset: 3px; background: #122239; color: #e2eff6; font: 27px/1.4 var(--pixel); letter-spacing: 3px; text-decoration: none; transition: background .2s, transform .2s; }
.play-button:hover { background: #1c354c; transform: translateY(-2px); color: #f4c1d7; }
.hero-actions { display: grid; gap: 16px; max-width: 660px; margin-inline: auto; }
.external-note { margin: 10px 0 0; color: var(--drift); font: 16px var(--pixel); letter-spacing: 1px; }
.hero-links { max-width: 660px; margin-inline: auto; display: flex; justify-content: space-between; margin-top: 27px; font: 18px var(--pixel); }
.hero-links a { text-decoration: none; padding: 8px 0; }
.depth-label { position: absolute; color: #69859b; font: 15px var(--pixel); letter-spacing: 2px; }
.depth-left { left: 28px; top: 340px; }
.depth-right { right: 28px; bottom: 70px; writing-mode: vertical-rl; }
.guide-shell { max-width: 940px; padding: 0 36px; margin: auto; }
.guide-intro { display: flex; justify-content: space-between; gap: 12px; padding: 21px 0; color: var(--drift); border-top: 1px solid var(--line); border-bottom: 1px solid var(--line); font: 16px var(--pixel); letter-spacing: 1px; }
.guide-section { padding: 65px 0 56px; border-bottom: 1px solid var(--line); }
.section-marker { color: var(--pink); margin: 0 0 16px; }
.section-heading { display: flex; align-items: center; justify-content: space-between; gap: 20px; }
h2 { font: 42px/1.1 var(--pixel); font-weight: 400; margin: 0 0 22px; }
.depth-tick { color: #657f96; font: 16px var(--pixel); flex-shrink: 0; align-self: flex-start; padding-top: 13px; }
p { margin: 0 0 17px; }
.guide-section > p:not(.section-marker) { max-width: 740px; }
.guide-section p { color: var(--drift); }
.guide-section .section-marker { color: var(--pink); }
.guide-section .lead { font: 26px/1.35 var(--pixel); color: var(--foam); }
strong { color: var(--foam); font-weight: 600; }
.source-note { font-size: 12px; line-height: 1.8; margin: 24px 0 0; }
.source-note a { color: #b6c9d7; }
.steps { padding: 0; margin: 8px 0 30px; list-style: none; }
.steps li { display: grid; grid-template-columns: 48px 1fr; gap: 18px; padding: 22px 0; border-bottom: 1px dashed #25344a; }
.steps li:last-child { border: 0; }
.step-number { font: 32px var(--pixel); color: var(--cyan); }
h3 { font: 28px/1.2 var(--pixel); margin: 0 0 8px; font-weight: 400; }
.steps p { margin: 0; }
.mode-list { border-top: 1px solid var(--line); margin-top: 30px; }
.mode-list > a { display: grid; grid-template-columns: 43px 1fr 20px; gap: 20px; align-items: center; padding: 20px 8px; text-decoration: none; border-bottom: 1px solid var(--line); }
.mode-list > a:hover { background: #102132; }
.mode-symbol { font: 35px var(--pixel); color: var(--cyan); }
.mode-list strong { display: block; font: 28px var(--pixel); }
.mode-list small { display: block; color: var(--drift); font-size: 12px; margin-top: 6px; }
details { border-bottom: 1px solid var(--line); }
details:last-child { border-bottom: 0; }
summary { cursor: pointer; padding: 21px 5px; font: 24px/1.25 var(--pixel); color: var(--foam); }
summary::marker { color: var(--pink); font-size: 16px; }
details[open] summary { color: var(--cyan); }
details p { padding: 0 5px 8px 23px; font-size: 14px; }
.final-dive { padding: 75px 0 80px; text-align: center; }
.final-dive > img { image-rendering: pixelated; margin-bottom: 20px; }
.final-dive .section-marker { color: var(--drift); font-size: 15px; }
.final-dive h2 { font-size: 48px; margin: 23px 0 32px; }
.final-dive .play-button { max-width: 580px; margin: auto; }
/* Footer navigation keeps every guide available on every content page. */
.site-footer { border-top: 1px solid var(--line); padding: 32px max(36px, calc((100% - 868px) / 2)) 24px; background: #070d17; }
.footer-columns { display: grid; grid-template-columns: repeat(4, max-content); justify-content: space-between; gap: 24px; }
.footer-column h2 { margin: 0 0 12px; color: var(--drift); font: 400 13px/1.5 Verdana, sans-serif; }
.footer-column ul { list-style: none; margin: 0; padding: 0; }
.footer-column a, .footer-column button { display: inline-block; max-width: 100%; padding: 5px 0; font: 14px/1.5 Verdana, sans-serif; letter-spacing: 0; text-transform: none; text-decoration: none; overflow-wrap: anywhere; }
.footer-column button { border: 0; background: none; color: inherit; text-align: left; }
.footer-column a:hover, .footer-column button:hover { color: var(--cyan); text-decoration: underline; }
.footer-bottom { display: flex; justify-content: space-between; align-items: flex-start; gap: 24px; margin-top: 24px; padding-top: 20px; border-top: 1px solid var(--line); }
.footer-brand { font: 22px var(--pixel); color: var(--pink); text-decoration: none; letter-spacing: 2px; }
.site-footer p { color: var(--drift); font-size: 12px; line-height: 1.6; max-width: 640px; margin: 8px 0 0; }
.footer-top { flex-shrink: 0; padding: 5px 0; font: 12px/1.5 Verdana, sans-serif; }
.site-footer .site-version { font-size: 11px; margin: 12px 0 0; letter-spacing: .04em; }
.site-version:not(:has(span:not(:empty))) { display: none; }
.consent { position: fixed; z-index: 5; bottom: 20px; right: 20px; max-width: 450px; padding: 22px; background: #142338; border: 1px solid var(--cyan); box-shadow: 0 8px 40px #02060dcc; }
.consent p:first-child { font: 24px var(--pixel); margin-bottom: 10px; }
.consent .consent-detail { font-size: 12px; color: var(--drift); }
.consent > div { display: flex; gap: 12px; }
.consent button { padding: 8px 13px; border: 1px solid var(--drift); background: transparent; color: var(--foam); font: 19px var(--pixel); min-height: 44px; }
.consent button[data-consent="granted"] { border-color: var(--cyan); }
.consent-status { font-size: 12px; color: var(--pink); margin: 8px 0 0; }
.prose-page { max-width: 800px; margin: 0 auto; padding: 65px 28px; min-height: 70vh; }
.prose-page h1 { font: 48px var(--pixel); color: var(--foam); text-shadow: none; letter-spacing: 0; margin: 0 0 26px; }
.prose-page h2 { font-size: 30px; margin-top: 34px; }
.prose-page p { color: var(--drift); }
.article-shell { max-width: 940px; margin: auto; padding: 32px 36px 72px; }
.breadcrumb { display: flex; flex-wrap: wrap; align-items: center; gap: 12px; color: var(--drift); font-size: 13px; }
.breadcrumb a { font: inherit; text-transform: none; letter-spacing: 0; text-decoration: underline; }
.article-header { padding: 48px 0 36px; border-bottom: 1px solid var(--line); }
.article-header h1 { max-width: 800px; font: clamp(42px, 6vw, 72px)/1.05 var(--pixel); letter-spacing: 0; text-shadow: none; margin: 0 0 24px; }
.article-intro { max-width: 740px; color: var(--drift); font-size: 17px; line-height: 1.8; }
.checked-date { color: var(--drift); font: 16px var(--pixel); margin: 22px 0; }
.article-header .play-button { max-width: 520px; text-align: center; }
.article-toc { padding: 24px 0; border-bottom: 1px solid var(--line); }
.article-toc p { font: 16px var(--pixel); color: var(--cyan); letter-spacing: 2px; margin: 0 0 12px; }
.article-toc ol { display: grid; grid-template-columns: 1fr 1fr; gap: 4px 32px; padding-left: 22px; margin: 0; }
.article-toc a { display: inline-block; font: 14px/1.6 Verdana, sans-serif; letter-spacing: 0; text-transform: none; text-decoration: underline; }
.article-shell section { padding: 38px 0 20px; border-bottom: 1px solid var(--line); }
.article-shell section h2 { font-size: 36px; margin-bottom: 20px; }
.article-shell section p, .article-shell section li, .mode-comparison dd { max-width: 740px; color: var(--drift); }
.article-shell section li { margin-bottom: 12px; }
.article-shell a { overflow-wrap: anywhere; }
.article-shell blockquote { margin: 24px 0; padding: 24px; background: var(--panel); }
.article-shell blockquote p { font: 29px/1.3 var(--pixel); color: var(--foam); }
.article-shell cite { font-size: 12px; font-style: normal; }
.mode-comparison { margin: 24px 0; }
.mode-comparison > div { display: grid; grid-template-columns: 160px 1fr; gap: 24px; padding: 20px 0; border-top: 1px solid var(--line); }
.mode-comparison dt { font: 26px var(--pixel); color: var(--cyan); }
.mode-comparison dd { margin: 0; font-size: 14px; }
.article-shell .depth-equation { font: clamp(23px, 4vw, 34px)/1.4 var(--pixel); color: var(--cyan); padding: 20px 0; }
.video-embed { margin: 28px 0; }
.video-poster { position: relative; display: block; width: 100%; min-height: 200px; aspect-ratio: 16 / 9; padding: 0; border: 1px solid var(--line); background: var(--panel); color: var(--foam); overflow: hidden; }
.video-poster img { width: 100%; height: 100%; object-fit: cover; }
.video-play-icon { position: absolute; left: 50%; top: 50%; transform: translate(-50%, -50%); background: #c21727; color: #fff; border-radius: 12px; padding: 8px 24px; font-size: 28px; line-height: 1.5; }
.video-poster:hover .video-play-icon { background: #e11c30; }
.video-play-label { position: absolute; bottom: 12px; left: 12px; padding: 4px 12px; background: var(--sea); font: 22px var(--pixel); }
.video-embed iframe { display: block; width: 100%; min-height: 200px; aspect-ratio: 16 / 9; border: 0; }
.video-embed figcaption { margin-top: 12px; color: var(--drift); font-size: 12px; line-height: 1.8; }
.article-sources { font-size: 13px; }
.article-sources ul { padding-left: 20px; }
.related-guides { display: flex; flex-wrap: wrap; gap: 12px 28px; padding-top: 28px; }
.related-guides a { font: 20px/1.5 var(--pixel); letter-spacing: 0; text-transform: none; text-decoration: underline; }
.prompt-list { list-style: none; padding: 0; border-top: 1px solid var(--line); }
.prompt-list a { display: block; padding: 18px 8px; border-bottom: 1px solid var(--line); font: 25px/1.35 var(--pixel); text-decoration: none; }
.prompt-list a:hover { background: var(--panel); }
.recorded-result { margin: 0 0 24px; padding: 16px 22px; background: var(--panel); }
.recorded-result > div { display: grid; grid-template-columns: 180px 1fr; gap: 16px; padding: 10px 0; }
.recorded-result dt { color: var(--drift); font-size: 13px; }
.recorded-result dd { margin: 0; color: var(--cyan); font: 26px/1.3 var(--pixel); }
.comparison-scroll { overflow-x: auto; }
.comparison-scroll:focus-visible { outline: 3px solid var(--pink); outline-offset: 3px; }
.game-comparison { border-collapse: collapse; width: 100%; font-size: 14px; text-align: left; }
.game-comparison caption { text-align: left; color: var(--drift); font-size: 12px; margin-bottom: 16px; }
.game-comparison th, .game-comparison td { padding: 16px 12px; border-bottom: 1px solid var(--line); vertical-align: top; }
.game-comparison td { color: var(--drift); }
.game-comparison th:first-child { width: 25%; }
@keyframes drift { 50% { transform: translateY(-7px); } }
@media (max-width: 720px) {
  .site-footer { padding-inline: 23px; }
  .footer-columns { grid-template-columns: repeat(2, minmax(0, 1fr)); gap: 32px 24px; }
  .footer-bottom { flex-direction: column; gap: 12px; }
  .site-header { padding: 12px 20px; gap: 16px; flex-wrap: wrap; }
  .wordmark { font-size: 36px; }
  .wordmark span { font-size: 28px; }
  .site-header nav { gap: 8px 16px; } .site-header nav a { font-size: 17px; }
  .hero { --surface: 270px; min-height: 660px; }
  .hero-content { padding-top: 37px; }
  h1 { font-size: clamp(58px, 13.4vw, 96px); letter-spacing: 6px; }
  #hero-title { font-size: clamp(54px, 14vw, 100px); }
  .hero-subtitle { font-size: clamp(36px, 8.5vw, 54px); margin-top: 20px; }
  .hero-eyebrow { font-size: 14px; letter-spacing: 1px; margin-bottom: 12px; }
  .hero-description { margin-top: 62px; font-size: 21px; }
  .hero-tagline { font-size: 25px; }
  .play-button { font-size: 22px; letter-spacing: 1px; padding: 15px 8px; }
  .depth-label { display: none; }
  .guide-shell { padding: 0 23px; }
  .guide-intro { font-size: 13px; letter-spacing: 0; flex-wrap: wrap; }
  .guide-section { padding: 45px 0; }
  h2 { font-size: 35px; }
  .depth-tick { display: none; }
  .steps li { grid-template-columns: 32px 1fr; gap: 12px; }
  .article-shell { padding: 24px 23px 48px; }
  .article-header { padding-top: 32px; }
  .article-toc ol { grid-template-columns: 1fr; }
  .mode-comparison > div { grid-template-columns: 1fr; gap: 8px; }
  .recorded-result > div { grid-template-columns: 1fr; gap: 4px; }
  .game-comparison th, .game-comparison td { padding: 12px 8px; font-size: 12px; }
  .mode-list > a { gap: 8px; }
  .final-dive h2 { font-size: 39px; }
  .consent { inset: auto 12px 12px; max-width: none; }
}
@media (prefers-reduced-motion: reduce) { html { scroll-behavior: auto; } *, *::before, *::after { animation: none !important; transition: none !important; } }

/* Reset page: the answer comes before the explanation. */
.article-header.reset-header { padding-top: 28px; }
.reset-header h1 { font-size: clamp(32px, 4vw, 48px); margin-bottom: 30px; }
.reset-label { font: 16px var(--pixel); letter-spacing: 2px; color: var(--cyan); margin: 0; }
.reset-time { display: block; font: clamp(68px, 12vw, 112px)/1.1 var(--pixel); color: var(--foam); margin: 8px 0; }
.reset-date { color: var(--drift); font-size: 14px; margin: 0; overflow-wrap: anywhere; }
.reset-countdown-row { display: flex; align-items: center; flex-wrap: wrap; gap: 12px 24px; margin: 26px 0; padding-top: 20px; border-top: 1px solid var(--line); }
.reset-countdown { font: clamp(40px, 7vw, 64px)/1 var(--pixel); color: var(--cyan); font-variant-numeric: tabular-nums; }
.reset-countdown-label { font: 16px/1.5 var(--pixel); color: var(--drift); letter-spacing: 1px; }
.reset-countdown-label span { font-size: 13px; }
.reset-rule { font-size: 14px; color: var(--drift); }
.reset-rule a { display: inline-block; margin-left: 8px; text-decoration: underline; }
.reset-status:empty { display: none; }
.reset-status { font-size: 14px; color: var(--pink); }