:root { color-scheme: dark; --bg: #080f17; --panel: #101b27; --text: #eef0ed; --muted: #a0afbc; --accent: #ddc294; --mint: #a2d5bf; --line: #ffffff1c; font: 16px/1.65 "Segoe UI", Tahoma, Arial, sans-serif; }
* { box-sizing: border-box; }
body { margin: 0; color: var(--text); background: radial-gradient(ellipse at 80% 5%, #18304060, transparent 48%), var(--bg); min-width: 280px; }
body::before { content: ""; position: fixed; inset: 0; z-index: -1; opacity: .32; pointer-events: none; background-image: radial-gradient(1px 1px at 12% 27%, #b8ccd5 90%, transparent), radial-gradient(1px 1px at 84% 14%, #b8ccd5 90%, transparent), radial-gradient(1px 1px at 47% 81%, #b8ccd5 90%, transparent); background-size: 350px 330px; }
button, input, select, textarea { font: inherit; }
button, a, input, select, textarea { -webkit-tap-highlight-color: transparent; }
button, select { cursor: pointer; }
button, a { touch-action: manipulation; }
button { color: inherit; }
a { color: inherit; text-underline-offset: .2em; }
a:hover { color: var(--accent); }
button:disabled { cursor: default; opacity: .6; }
button:focus-visible, a:focus-visible, input:focus-visible, select:focus-visible, textarea:focus-visible, summary:focus-visible { outline: 3px solid var(--accent); outline-offset: 5px; }
[hidden] { display: none !important; }
::selection { color: var(--bg); background: var(--accent); }
.skip-link { position: fixed; top: -90px; inset-inline-start: 20px; padding: 12px 20px; background: var(--accent); color: var(--bg); z-index: 20; }
.skip-link:focus { top: 15px; }
.site-header { min-height: 100px; max-width: 1440px; margin: auto; padding: 20px 4%; display: flex; align-items: center; gap: 30px; border-bottom: 1px solid var(--line); }
.brand { display: inline-flex; align-items: center; gap: 12px; font-size: .76rem; letter-spacing: 2px; line-height: 1.3; text-decoration: none; white-space: nowrap; font-weight: 700; }
.brand-light { font-weight: 350; }
.brand small { display: block; margin-top: 7px; color: var(--accent); letter-spacing: .7px; font: .65rem ui-monospace, Consolas, monospace; }
.site-header nav { display: flex; align-items: center; gap: 24px; margin-inline: auto; }
.site-header nav a { position: relative; color: var(--muted); font-size: .85rem; text-decoration: none; padding-block: 10px; }
.site-header nav a[aria-current="page"] { color: var(--text); }
.site-header nav a[aria-current="page"]::after { position: absolute; content: ""; height: 2px; bottom: 0; inset-inline-start: 0; width: 22px; background: var(--accent); }
.header-actions { display: flex; align-items: center; gap: 15px; }
.language-label { display: grid; gap: 2px; font-size: .6rem; color: var(--muted); }
.language-label select { width: auto; border: none; padding: 3px 16px 3px 0; font-size: .82rem; background: transparent; }
.viewer-link { font-size: .8rem; white-space: nowrap; color: var(--accent); text-decoration: none; }
main { max-width: 1200px; padding: 56px 32px 72px; margin: 0 auto; min-height: 70vh; }
main:focus { outline: none; }
h1, h2, h3, p { margin-top: 0; }
h1 { font-size: clamp(2.3rem, 4.8vw, 4.2rem); font-weight: 400; line-height: 1.12; letter-spacing: -.045em; margin-block: 20px 24px; max-width: 850px; text-wrap: balance; }
h2 { font-size: clamp(1.3rem, 2.3vw, 1.85rem); font-weight: 450; line-height: 1.3; letter-spacing: -.025em; }
h3 { font-weight: 550; font-size: 1.12rem; line-height: 1.4; }
p { margin-bottom: 1.25em; }
.eyebrow { font: .65rem/1.5 ui-monospace, Consolas, monospace; letter-spacing: 2px; color: var(--accent); text-transform: uppercase; }
.muted, .lead, .small-note { color: var(--muted); }
.small-note { font-size: .8rem; line-height: 1.65; }
.lead { font-size: 1.08rem; max-width: 620px; }
.hero { display: grid; grid-template-columns: 1.3fr .9fr; align-items: center; min-height: 340px; gap: 20px; margin-bottom: 30px; }
.hero h1 { max-width: 630px; }
.hero-copy { position: relative; z-index: 1; }
.hero-orbits { position: relative; aspect-ratio: 1; max-width: 370px; width: 100%; margin: 0 auto; pointer-events: none; }
.hero-orbits::before, .hero-orbits::after { content: ""; position: absolute; border: 1px solid #d5e6ff20; border-radius: 50%; inset: 6%; transform: rotate(-25deg) scaleY(.73); }
.hero-orbits::after { inset: 24%; border-style: dashed; }
.hero-star { position: absolute; width: 68px; height: 68px; top: 43%; left: 40%; border-radius: 50%; background: radial-gradient(circle at 35% 30%, #ffe2a1, #db943e 70%); box-shadow: 0 0 65px #ffc86d26, 0 0 110px #ffc86d12; }
.hero-orbits .planet-art { position: absolute; }
.hero-earth { --world: #6b9eae; width: 54px; height: 54px; top: 13%; left: 52%; }
.hero-mars { --world: #c28b6e; width: 30px; height: 30px; top: 72%; left: 25%; }
.hero-saturn { --world: #c8b48d; width: 45px; height: 45px; top: 65%; left: 85%; }
.hero-saturn::after { content: ""; position: absolute; inset: 25% -50%; border: 5px solid #c8b48d70; border-radius: 50%; transform: rotate(-30deg); }
.orbit-coordinate { position: absolute; bottom: 0; right: 0; font: .65rem ui-monospace, Consolas, monospace; color: var(--muted); letter-spacing: 1px; }
.planet-art { display: inline-block; width: 68px; height: 68px; flex-shrink: 0; border-radius: 50%; background: radial-gradient(ellipse at 30% 28%, #ffffff40, transparent 45%), repeating-linear-gradient(160deg, #ffffff0e 0 3%, transparent 4% 12%), var(--world, #85a8b8); box-shadow: inset -18px -6px 22px #000b, 0 0 34px #ffffff05; position: relative; }
.actions { display: flex; gap: 12px; flex-wrap: wrap; align-items: center; }
.button { display: inline-flex; gap: 16px; align-items: center; justify-content: center; min-height: 46px; padding: 11px 20px; border: 1px solid transparent; border-radius: 5px; font-size: .88rem; font-weight: 550; color: #121923; background: var(--accent); text-decoration: none; line-height: 1.45; }
.button:hover { background: #edd1a3; color: #121923; }
.button.secondary { background: #ffffff04; color: var(--text); border-color: var(--line); }
.button.secondary:hover { background: #ffffff0c; border-color: #ddc29480; }
.text-button { display: inline-flex; gap: 8px; align-items: center; min-height: 44px; padding: 5px 0; border: 0; background: none; color: var(--accent); text-decoration: none; font-size: .86rem; text-align: start; }
.text-button:hover { color: #ffdfaa; text-decoration: underline; }
.text-button svg { width: 15px; height: 15px; }
.info-strip { display: flex; flex-wrap: wrap; gap: 12px 28px; padding-block: 17px; margin-block: 26px 36px; border-block: 1px solid var(--line); color: var(--muted); font-size: .76rem; }
.info-strip span { display: flex; align-items: center; gap: 8px; }
.info-strip span::before { content: ""; width: 4px; height: 4px; border-radius: 50%; background: var(--mint); }
.section-heading { display: flex; gap: 20px; justify-content: space-between; align-items: start; margin-block: 32px 20px; }
.section-heading h2 { margin-bottom: 7px; }
.section-heading p { margin: 0; }
.mission-grid { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; }
.mission-card { display: flex; flex-direction: column; position: relative; padding: 27px; background: linear-gradient(145deg, #172331a8, #0e182399); border: 1px solid var(--line); border-radius: 10px; overflow: hidden; transition: border-color .2s, transform .2s; }
.mission-card:hover { border-color: #ddc29460; transform: translateY(-3px); }
.card-top { display: flex; justify-content: space-between; align-items: start; margin-bottom: 23px; min-height: 90px; }
.mission-index { color: var(--muted); font: .7rem ui-monospace, Consolas, monospace; }
.mission-card h3 { font-size: 1.3rem; margin-bottom: 12px; }
.mission-card p { color: var(--muted); font-size: .9rem; }
.mission-card .card-action { margin-top: auto; padding-top: 18px; display: flex; justify-content: space-between; align-items: center; gap: 10px; border-top: 1px solid var(--line); }
.badge { border: 1px solid #a2d5bf45; color: var(--mint); border-radius: 20px; padding: 3px 10px; font-size: .68rem; white-space: nowrap; }
.progress-summary { text-align: end; font-size: .75rem; min-width: 130px; }
.progress-track { display: block; margin-top: 10px; height: 3px; background: #ffffff15; }
.progress-track > span { display: block; height: 100%; background: var(--mint); }
.support-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; margin-block: 35px; }
.panel { background: #101b2780; border: 1px solid var(--line); border-radius: 10px; padding: 27px; }
.panel p:last-child { margin-bottom: 0; }
.support-grid .panel h3 { margin-bottom: 9px; }
.support-grid .panel p { color: var(--muted); font-size: .9rem; }
.access-bar { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 18px; padding: 20px 0; border-block: 1px solid var(--line); margin-block: 30px 20px; align-items: center; }
.access-options { display: flex; gap: 20px; align-items: center; flex-wrap: wrap; }
.control-label { color: var(--muted); font-size: .77rem; display: grid; gap: 6px; }
select, textarea { border: 1px solid #ffffff2b; color: var(--text); background: #111f2c; padding: 10px 12px; border-radius: 5px; max-width: 100%; }
select { min-height: 43px; }
.access-bar select { font-size: .8rem; padding: 6px 12px; }
.offline-control { max-width: 470px; }
.offline-control p { margin: 3px 0 0; font-size: .73rem; color: var(--muted); }
.page-heading { max-width: 820px; margin-bottom: 35px; }
.page-heading h1 { font-size: clamp(2.2rem, 4vw, 3.4rem); }
.page-toolbar { display: flex; justify-content: space-between; align-items: center; gap: 20px; margin-bottom: 16px; }
.step-nav { display: flex; border-bottom: 1px solid var(--line); margin: 32px 0; gap: 30px; }
.step-nav button { padding: 12px 0; background: none; color: var(--muted); border: none; border-bottom: 2px solid transparent; font-size: .86rem; }
.step-nav button[aria-current="step"] { color: var(--accent); border-bottom-color: var(--accent); }
.step-nav button span { font: .7rem ui-monospace, Consolas, monospace; margin-inline-end: 9px; opacity: .7; }
.lesson-grid { display: grid; grid-template-columns: minmax(0, 1.6fr) minmax(220px, .8fr); gap: 32px; align-items: start; }
.lesson-copy { font-size: 1.05rem; line-height: 1.9; }
.lesson-copy > p { max-width: 720px; }
.lesson-note { border-inline-start: 2px solid var(--accent); padding-inline-start: 20px; margin-bottom: 30px; }
.lesson-note strong { color: var(--accent); display: block; font-size: .76rem; margin-bottom: 8px; }
.lesson-note p { margin: 0; font-size: .92rem; }
.lesson-footer { margin-top: 32px; padding-top: 22px; border-top: 1px solid var(--line); display: flex; justify-content: space-between; gap: 15px; align-items: center; }
.source-link { font-size: .76rem; color: var(--muted); overflow-wrap: anywhere; }
.experiment { padding: 30px; background: #0d1926; border: 1px solid var(--line); border-radius: 10px; }
.experiment h2 { margin-bottom: 12px; }
.experiment .instruction { color: var(--muted); max-width: 740px; }
.observation-note { margin-top: 24px; padding: 20px 23px; border-radius: 6px; background: #a2d5bf08; border-inline-start: 2px solid var(--mint); color: #ceddd4; }
.observation-note p { margin: 8px 0 0; }
.orbit-demo { position: relative; height: 285px; width: min(100%, 490px); margin: 30px auto 40px; direction: ltr; }
.orbit-ring { position: absolute; inset: 12px 35px; border: 1px solid #d9eaff26; border-radius: 50%; }
.orbit-ring.earth-ring { inset: 65px 110px; }
.orbit-sun { position: absolute; inset: calc(50% - 17px) auto auto calc(50% - 17px); width: 34px; height: 34px; border-radius: 50%; background: #e9b56a; box-shadow: 0 0 35px #edb35a30; }
.orbit-marker { position: absolute; left: calc(50% + var(--x) * 1px); top: calc(50% + var(--y) * 1px); width: 16px; height: 16px; border-radius: 50%; background: var(--world); transform: translate(-50%, -50%); }
.orbit-marker span { position: absolute; top: 19px; left: 8px; color: var(--text); font-size: .75rem; white-space: nowrap; }
.range-label { display: flex; flex-wrap: wrap; justify-content: space-between; gap: 10px; align-items: center; font-size: .87rem; }
output { font-variant-numeric: tabular-nums; color: var(--accent); }
input[type="range"] { display: block; width: 100%; margin: 16px 0; accent-color: var(--accent); min-height: 30px; cursor: pointer; }
.comparison-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 24px; margin-top: 25px; }
.comparison-card { padding: 25px; background: #ffffff03; border: 1px solid var(--line); border-radius: 8px; min-width: 0; }
.comparison-card .control-label { margin-bottom: 22px; }
.comparison-card .planet-art { width: 72px; height: 72px; margin-bottom: 16px; }
.facts { margin: 0; }
.facts > div { margin-top: 15px; padding-top: 12px; border-top: 1px solid var(--line); }
.facts dt { color: var(--muted); font-size: .74rem; }
.facts dd { margin: 5px 0 0; color: var(--text); font-size: 1rem; }
.diameter-bar { height: 5px; width: 100%; background: #ffffff0a; margin-top: 15px; }
.diameter-bar span { display: block; height: 100%; background: var(--mint); }
.phase-scene { text-align: center; padding-block: 25px; }
.phase-disc { display: block; width: 156px; height: 156px; border-radius: 50%; margin: 0 auto 22px; border: 1px solid #d5ddea4d; background: #05090e; box-shadow: 0 0 65px #d7e6f209; }
.phase-disc[data-phase="1"] { background: linear-gradient(90deg, #05090e 50%, #dae1dd 50%); }
.phase-disc[data-phase="2"] { background: #dae1dd; box-shadow: inset -5px -7px 25px #767c7750, 0 0 65px #d7e6f209; }
.phase-disc[data-phase="3"] { background: linear-gradient(90deg, #dae1dd 50%, #05090e 50%); }
.phase-scene h3 { margin: 5px 0; }
.phase-options { display: flex; justify-content: space-between; font-size: .68rem; color: var(--muted); gap: 12px; }
.quiz-form { max-width: 800px; }
fieldset { border: 0; padding: 0; margin: 0 0 32px; min-width: 0; }
legend { font-weight: 550; margin-bottom: 14px; padding: 0; }
.question-number { color: var(--accent); font: .75rem ui-monospace, Consolas, monospace; margin-inline-end: 12px; }
.answer-option { display: flex; gap: 13px; align-items: start; padding: 14px 17px; margin-block: 8px; border: 1px solid var(--line); border-radius: 6px; background: #ffffff02; cursor: pointer; }
.answer-option:has(input:checked) { border-color: var(--accent); background: #ddc29409; }
.answer-option:has(input:focus-visible) { outline: 3px solid var(--accent); outline-offset: 3px; }
.answer-option input { margin-top: 7px; accent-color: var(--accent); }
.answer-option.is-correct { border-color: #a2d5bf90; background: #a2d5bf09; }
.answer-explanation { color: #c8d9d1; margin-top: 13px; padding-inline-start: 17px; border-inline-start: 2px solid var(--mint); }
.answer-explanation strong { display: block; margin-bottom: 5px; }
.quiz-error { padding: 12px 17px; border: 1px solid #ebbb9070; border-radius: 5px; color: #f0cba7; }
.result-banner { padding: 28px; margin-bottom: 30px; border: 1px solid #a2d5bf55; border-radius: 10px; background: radial-gradient(ellipse at top right, #a2d5bf13, transparent), #101c25; }
.result-banner h2 { color: var(--mint); }
.result-score { font-size: 2.4rem; font-weight: 350; color: var(--accent); margin-bottom: 12px; }
.atlas-grid { display: grid; grid-template-columns: repeat(5, 1fr); gap: 10px; }
.world-button { min-width: 0; border: 1px solid var(--line); border-radius: 8px; background: #101b2770; padding: 20px 12px 14px; display: grid; gap: 14px; justify-items: center; text-align: center; }
.world-button .planet-art { width: 43px; height: 43px; }
.world-button[aria-pressed="true"] { border-color: var(--accent); background: #ddc2940b; }
.world-button span:last-child { font-size: .82rem; }
.atlas-detail { margin-top: 25px; display: grid; grid-template-columns: 1.4fr 1fr; gap: 40px; }
.atlas-detail h2 { font-size: 2rem; }
.atlas-detail .facts { display: grid; grid-template-columns: 1fr 1fr; gap: 0 20px; }
.resource-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 20px; }
.resource-card { display: flex; flex-direction: column; }
.resource-card .actions { margin-top: auto; padding-top: 15px; }
.resource-number { color: var(--accent); font: .75rem ui-monospace, Consolas, monospace; margin-bottom: 22px; }
.resource-card p { color: var(--muted); }
.resource-list { color: var(--muted); padding-inline-start: 24px; }
.resource-list li { padding-inline-start: 5px; margin-block: 9px; }
.share-panel { margin-top: 25px; }
.share-panel textarea { width: 100%; font: .8rem/1.6 ui-monospace, Consolas, monospace; direction: ltr; resize: vertical; min-height: 108px; margin-block: 14px; }
.share-panel label { display: block; }
.research-steps { display: grid; grid-template-columns: repeat(3, 1fr); gap: 18px; margin-block: 30px; }
.research-steps p { margin: 14px 0 0; color: var(--muted); }
.feedback { margin-top: 35px; border-top: 1px solid var(--line); padding-top: 25px; }
.feedback summary { cursor: pointer; padding: 12px 0; font-size: 1.05rem; color: var(--accent); }
.feedback-form { max-width: 730px; margin-top: 20px; }
.feedback-form fieldset { margin-bottom: 20px; }
.rating-options { display: flex; gap: 10px; flex-wrap: wrap; }
.rating-options label { cursor: pointer; border: 1px solid var(--line); padding: 9px 14px; border-radius: 5px; }
.rating-options label:has(input:checked) { border-color: var(--mint); background: #a2d5bf0a; }
.rating-options input { accent-color: var(--mint); }
.feedback-form textarea { display: block; width: 100%; min-height: 110px; margin-block: 10px 18px; resize: vertical; }
.site-footer { max-width: 1440px; margin: 0 auto; padding: 26px 4%; border-top: 1px solid var(--line); display: flex; gap: 20px; justify-content: space-between; color: var(--muted); font-size: .74rem; }
.site-footer p { margin: 0; max-width: 580px; }
.signature { font: 1.7rem ui-monospace, Consolas, monospace; color: var(--text); line-height: 1; }
.signature span { color: var(--accent); }
.footer-credit { display: flex; align-items: center; gap: 16px; }
.notice { position: fixed; bottom: 25px; inset-inline: 20px; width: max-content; max-width: calc(100% - 40px); margin-inline: auto; padding: 13px 20px; border: 1px solid #ddc29465; border-radius: 6px; background: #142130; color: var(--text); font-size: .85rem; z-index: 30; box-shadow: 0 10px 40px #0007; }
.notice:empty { display: none; }
.dialog { color: var(--text); background: #11202e; border: 1px solid var(--line); border-radius: 10px; max-width: min(480px, calc(100% - 40px)); padding: 28px; }
.dialog::backdrop { background: #030810c9; }
.dialog p { color: var(--muted); }
.fallback-links { display: flex; flex-wrap: wrap; gap: 18px; margin-block: 20px; }
html.large-text { font-size: 20px; }
html[dir="rtl"] h1, html[dir="rtl"] h2, html[dir="rtl"] h3 { letter-spacing: 0; }
html[dir="rtl"] .eyebrow { letter-spacing: .5px; }
html[dir="rtl"] .language-label select { padding-inline: 0 16px; }
body.is-embedded .site-header { min-height: 70px; padding-block: 14px; }
body.is-embedded .site-header nav, body.is-embedded .viewer-link, body.is-embedded .site-footer, body.is-embedded .hero-orbits { display: none; }
body.is-embedded main { padding-top: 28px; }
body.is-embedded .hero { grid-template-columns: 1fr; min-height: auto; }
body.is-embedded .hero h1 { font-size: 2.6rem; }
body.is-embedded .header-actions { margin-inline-start: auto; }
@media (max-width: 1050px) { .site-header { flex-wrap: wrap; gap: 14px 20px; } .site-header nav { order: 3; flex-basis: 100%; margin: 0; gap: 28px; } .header-actions { margin-inline-start: auto; } .hero-orbits { max-width: 300px; } .mission-card { padding: 22px; } }
@media (max-width: 760px) { main { padding: 35px 22px 45px; } .hero { grid-template-columns: 1fr; position: relative; min-height: auto; } .hero-orbits { position: absolute; top: -10px; inset-inline-end: -20px; width: 200px; opacity: .2; z-index: -1; } .hero h1 { max-width: 580px; } .mission-grid { grid-template-columns: 1fr; } .mission-card { display: grid; grid-template-columns: 1fr; } .card-top { min-height: 48px; margin-bottom: 5px; } .card-top .planet-art { position: absolute; top: 28px; inset-inline-end: 26px; width: 48px; height: 48px; } .mission-card h3 { max-width: calc(100% - 60px); } .card-action { padding-top: 15px !important; } .support-grid, .lesson-grid, .resource-grid, .atlas-detail { grid-template-columns: 1fr; gap: 20px; } .research-steps { grid-template-columns: 1fr; } .atlas-grid { grid-template-columns: repeat(5, 1fr); gap: 7px; } .world-button { padding: 13px 4px 10px; } .world-button .planet-art { width: 33px; height: 33px; } .world-button span:last-child { font-size: .68rem; overflow-wrap: anywhere; } .site-footer { flex-direction: column; } .section-heading { align-items: center; } .progress-summary { max-width: 180px; } .panel, .experiment { padding: 22px; } .step-nav { gap: 20px; } }
@media (max-width: 430px) { .site-header { padding-inline: 20px; } .site-header nav { gap: 20px; overflow: auto; scrollbar-width: thin; } .site-header nav a { font-size: .76rem; white-space: nowrap; } .brand { font-size: .63rem; gap: 8px; letter-spacing: 1.1px; } .brand img { width: 27px; height: 27px; } .viewer-link { display: none; } main { padding-inline: 18px; } h1 { font-size: 2.35rem; } .info-strip { font-size: .7rem; gap: 10px 18px; } .section-heading { flex-wrap: wrap; } .progress-summary { text-align: start; flex-basis: 100%; max-width: none; } .comparison-grid { gap: 10px; } .comparison-card { padding: 15px 12px; } .comparison-card select { padding-inline: 6px; width: 100%; font-size: .79rem; } .comparison-card .planet-art { width: 52px; height: 52px; } .facts dd { font-size: .86rem; } .orbit-demo { height: 250px; } .orbit-ring { inset: 12px 20px; } .orbit-ring.earth-ring { inset: 62px 75px; } .phase-options { font-size: .61rem; gap: 6px; } .step-nav { gap: 16px; } .step-nav button { font-size: .78rem; } .step-nav button span { margin-inline-end: 6px; } }
@media (prefers-reduced-motion: reduce) { *, *::before, *::after { scroll-behavior: auto !important; transition: none !important; animation: none !important; } .mission-card:hover { transform: none; } }
@media print { :root { color-scheme: light; } body { color: #18212b; background: white; } .site-header, .site-footer, .access-bar, .feedback, .notice, .page-toolbar, .step-nav { display: none; } main { max-width: none; padding: 0; } .panel, .experiment, .mission-card { border-color: #bbb; background: white; break-inside: avoid; } .muted, .lead, .small-note { color: #444; } }