/* Oxygène Terre — photographs, questions and comfortable reading. */
:root{--reading-ink:#142d45;--reading-muted:#456179;--reading-blue:#0963e8;--reading-light:#eff6fd}
.welcome{padding-top:24px}.welcome-photo{position:relative;min-height:480px;overflow:hidden;border-radius:24px;background:#203f50;color:white}.welcome-photo>img{position:absolute;inset:0;width:100%;height:100%;object-fit:cover;object-position:70% 62%;animation:welcome-drift 24s ease-in-out infinite alternate}.welcome-photo:after{content:"";position:absolute;inset:0;background:linear-gradient(90deg,rgba(7,27,37,.89),rgba(7,27,37,.58) 45%,rgba(7,27,37,.08) 85%)}.welcome-copy{position:relative;z-index:1;max-width:660px;padding:64px 54px 94px}.welcome-copy .eyebrow{color:#c0e3ff;font-size:.88rem;letter-spacing:.05em}.welcome h1{font-size:clamp(2.5rem,4.6vw,4.3rem);line-height:1.06;letter-spacing:-.045em;margin:20px 0}.welcome-copy p{font-size:1.15rem;line-height:1.65;max-width:480px;color:#f1f6fa}.welcome .button{background:#fff;color:#144678;border-color:#fff}.welcome-read{color:white;display:inline-flex;align-items:center;gap:9px;font-size:1rem}.welcome-caption{position:absolute;z-index:2;right:26px;bottom:23px;display:flex;align-items:center;gap:12px;background:#122d3eae;border:1px solid #ffffff42;border-radius:10px;padding:10px 15px;color:white;font-size:.88rem}.welcome-shortcuts{display:grid;grid-template-columns:repeat(3,1fr);border-bottom:1px solid #d9e5ef;padding:22px 0;gap:25px}.welcome-shortcuts a{position:relative;display:grid;gap:4px;padding:4px 32px 4px 10px;color:var(--reading-ink)}.welcome-shortcuts a+a{border-left:1px solid #d9e5ef;padding-left:26px}.welcome-shortcuts span{color:var(--reading-muted);font-size:.875rem}.welcome-shortcuts strong{font-weight:550;font-size:1.04rem}.welcome-shortcuts .icon{position:absolute;right:0;top:50%;color:var(--reading-blue)}.journal-section{padding-top:75px;padding-bottom:20px}.journal-heading{display:flex;align-items:flex-end;justify-content:space-between;gap:30px;margin-bottom:27px}.journal-heading h2{font-size:clamp(1.8rem,3vw,2.55rem);line-height:1.18;letter-spacing:-.035em;max-width:670px;margin:10px 0 0}.journal-heading>p{color:var(--reading-muted);max-width:360px;font-size:1rem;line-height:1.65}.journal-heading>.text-link{flex-shrink:0}.journal-places{display:grid;grid-template-columns:repeat(3,minmax(0,1fr));gap:25px}.journal-places .card-image{aspect-ratio:1.45}.journal-places .place-card h3{font-size:1.45rem}.journal-places .place-card p{font-size:1rem;line-height:1.7}.earth-home{padding-top:65px}.earth-window{display:grid;grid-template-columns:1fr 1fr;border:1px solid #d6e4f1;overflow:hidden;border-radius:22px;background:#f2f8ff}.earth-window-photo{position:relative;background:#02070d;display:flex;align-items:center;justify-content:center;min-width:0;padding:36px 15px 56px}.earth-window-photo img{object-fit:contain;display:block;width:100%;max-height:620px;height:auto;aspect-ratio:1;transition:opacity .25s}.earth-image-credit{position:absolute;top:20px;left:23px;font-size:.8rem;color:#c9d6e4}.earth-full-image{position:absolute;bottom:21px;left:23px;font-size:.875rem;color:#d2e4fa;text-decoration:underline;text-underline-offset:4px}.earth-window-copy{padding:40px 36px;align-self:center;min-width:0}.earth-window h2{font-size:clamp(1.85rem,2.8vw,2.7rem);line-height:1.15;letter-spacing:-.035em;margin:12px 0 20px}.earth-window-copy>p{font-size:1rem;line-height:1.75;color:var(--reading-muted)}.earth-observation{border-left:3px solid #0866ef;padding:4px 0 4px 16px;margin:22px 0}.earth-observation>span{font-size:.875rem;font-weight:600;display:block;color:#075dd1}.earth-observation time{font-size:1rem;display:block;color:var(--reading-ink);margin:6px 0}.earth-observation p{font-size:.875rem;line-height:1.55;color:var(--reading-muted);margin:6px 0 0}.earth-window-actions{display:flex;align-items:center;gap:16px;flex-wrap:wrap;margin-top:20px}.earth-window-actions .button{min-height:44px;font-size:.9rem;padding:11px 16px}.earth-window-copy .earth-delay{font-size:.875rem;line-height:1.65;margin:20px 0 0}.earth-player{display:flex;gap:8px;align-items:center;flex-wrap:wrap}.earth-player button{border:1px solid #bdd2e6;background:#fff;color:#143b67;border-radius:8px;padding:10px 12px;min-height:44px;font:inherit;font-size:.9rem;cursor:pointer}.earth-player button:disabled{opacity:.5;cursor:default}.earth-player span{font-size:.875rem;color:var(--reading-muted)}.question-grid{display:grid;grid-template-columns:1fr 1fr;gap:26px}.question-grid>a{border:1px solid #d6e3ef;border-radius:18px;overflow:hidden;background:#fff;transition:box-shadow .2s,transform .2s}.question-grid img{width:100%;height:230px;object-fit:cover}.question-grid a>div{padding:27px}.question-grid h3{font-size:1.6rem;line-height:1.25;margin:12px 0}.question-grid p{font-size:1rem;line-height:1.7;color:var(--reading-muted);margin-bottom:22px}.question-grid>a:hover{transform:translateY(-4px);box-shadow:0 12px 30px #1c456a12}.all-lessons{margin-top:25px}.journal-note{display:grid;grid-template-columns:.65fr 1fr;align-items:center;gap:55px;padding-top:80px;padding-bottom:80px}.journal-note img{width:100%;height:300px;object-fit:cover;border-radius:18px}.journal-note h2{font-size:2.25rem;line-height:1.2;letter-spacing:-.035em;margin:12px 0 20px}.journal-note p{font-size:1.08rem;line-height:1.8;color:var(--reading-muted);max-width:600px}.journal-note .text-link{margin-top:16px}
@keyframes welcome-drift{from{transform:scale(1)}to{transform:scale(1.045)}}
.motion-paused .welcome-photo>img{animation:none}
@media(max-width:980px){.welcome-copy{padding:45px 35px 85px;max-width:590px}.welcome-photo{min-height:430px}.earth-window-copy{padding:28px}.journal-heading{align-items:flex-start;flex-direction:column;gap:15px}.journal-note{gap:30px}.earth-window h2{font-size:2rem}.journal-places{gap:18px}}
@media(max-width:700px){.welcome{padding-top:14px}.welcome-photo{border-radius:16px;min-height:470px}.welcome-copy{padding:33px 23px 82px}.welcome h1{font-size:2.65rem}.welcome-copy p{font-size:1.06rem}.welcome .hero-actions{align-items:flex-start;gap:17px}.welcome-caption{font-size:.8rem;left:18px;right:18px;bottom:18px;padding:10px}.welcome-photo:after{background:linear-gradient(90deg,#092938e8,#0e2c3ca6)}.welcome-shortcuts{grid-template-columns:1fr;gap:12px;padding:18px 0}.welcome-shortcuts a+a{border-left:0;border-top:1px solid #e0e9f1;padding:15px 30px 4px 10px}.welcome-shortcuts .icon{right:10px}.journal-section{padding-top:45px}.journal-heading h2{font-size:1.9rem}.journal-places{grid-template-columns:1fr}.journal-places .card-image{aspect-ratio:1.6}.earth-home{padding-top:40px}.earth-window{grid-template-columns:1fr}.earth-window-photo{padding:36px 22px 48px}.earth-window-photo img{max-height:420px}.earth-window-copy{padding:28px 23px}.earth-window-copy h2{font-size:2rem}.question-grid{grid-template-columns:1fr;gap:20px}.question-grid img{height:220px}.question-grid a>div{padding:22px}.journal-note{grid-template-columns:1fr;gap:24px;padding-top:55px;padding-bottom:50px}.journal-note img{height:220px}.journal-note h2{font-size:1.9rem}}
@media(prefers-reduced-motion:reduce){.welcome-photo>img{animation:none}.question-grid>a{transition:none}}
/* Questions, examples and definitions have distinct, predictable places. */
.understand-heading{padding-top:58px;padding-bottom:36px;max-width:1000px}.understand-heading h1{font-size:clamp(2.15rem,4vw,3.4rem);line-height:1.13;letter-spacing:-.04em;margin:15px 0 22px}.understand-heading>p{font-size:1.15rem;line-height:1.8;color:var(--reading-muted);max-width:760px}.explain-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:30px;padding-bottom:35px}.explain-card{display:grid;grid-template-columns:180px 1fr;border:1px solid #dbe6f0;background:#fff;border-radius:16px;overflow:hidden;transition:transform .2s,box-shadow .2s}.explain-card:hover{transform:translateY(-3px);box-shadow:0 8px 25px #21496812}.explain-card>img{width:100%;height:100%;min-height:265px;object-fit:cover}.explain-card>div{padding:25px 24px}.explain-card h2{font-size:1.4rem;line-height:1.3;margin:12px 0;letter-spacing:-.02em}.explain-card p{font-size:1rem;line-height:1.65;color:var(--reading-muted)}.explain-card .text-link{margin-top:18px;font-size:.9rem}.lesson-header{display:grid;grid-template-columns:1.12fr 1fr;gap:48px;padding-top:34px;padding-bottom:40px;align-items:center}.lesson-header h1{font-size:clamp(2.15rem,3.6vw,3.25rem);line-height:1.13;letter-spacing:-.045em;margin:18px 0 22px}.lesson-header .article-kicker{margin-top:27px}.lesson-header>div>p{font-size:1.13rem;line-height:1.8;color:var(--reading-muted)}.lesson-header>figure{margin:0;position:relative}.lesson-header>figure img{width:100%;height:365px;object-fit:cover;border-radius:18px}.lesson-header>figure figcaption{font-size:.8rem;color:var(--reading-muted);margin-top:8px}.lesson-layout{display:grid;grid-template-columns:235px minmax(0,760px);justify-content:space-between;gap:50px;padding-top:24px}.lesson-contents{position:sticky;top:115px;align-self:start;display:grid;gap:14px;border-top:2px solid #b4d0ec;padding-top:21px}.lesson-contents>a{display:flex;gap:9px;font-size:.91rem;line-height:1.5;color:var(--reading-muted)}.lesson-contents>a>span{color:#0866ef}.lesson-contents>a:hover{color:#0866ef}.lesson-body{min-width:0}.simple-answer{background:#ebf5ff;border-radius:15px;padding:25px 29px;border:1px solid #d4e8fa;margin-bottom:40px}.simple-answer p{font-size:1.2rem;line-height:1.75;color:#173d60;margin:10px 0 0}.lesson-chapter{position:relative;padding:14px 0 20px;scroll-margin-top:110px}.chapter-number{display:inline-block;color:#2972be;font-size:.875rem;font-weight:550;border-bottom:2px solid #aaccf2;padding-bottom:7px;margin-bottom:12px}.lesson-chapter h2{font-size:1.9rem;line-height:1.25;letter-spacing:-.025em;margin:0 0 21px;max-width:650px}.lesson-chapter>p{font-size:1.12rem;line-height:1.9;color:var(--reading-ink);max-width:69ch;margin:0 0 21px}.word-explained{border-left:3px solid #5d9ddd;padding:7px 0 7px 18px;margin:24px 0 15px}.word-explained strong{font-size:1rem;font-weight:600}.word-explained p{font-size:1rem;line-height:1.7;margin:5px 0 0;color:var(--reading-muted)}.lesson-example{margin:15px 0 48px;position:relative;border:1px solid #d7e5f0;border-radius:17px;overflow:hidden}.lesson-example>img{width:100%;max-height:390px;object-fit:cover;display:block}.lesson-example>.photo-credit{position:static;display:block;border-radius:0;text-align:right;background:#e6eef6;color:#385169;font-size:.75rem;padding:6px 12px;transform:none;max-width:none}.lesson-example figcaption{padding:24px 27px;background:#f8fbff}.lesson-example h3{font-size:1.35rem;line-height:1.35;margin:10px 0}.lesson-example figcaption p{font-size:1.03rem;line-height:1.75;margin:0 0 16px;color:var(--reading-muted)}.lesson-example .text-link{font-size:.9rem}.lesson-body .lesson-lab{margin:12px 0 48px;padding:27px;border-radius:17px;background:#eaf4ff;border:1px solid #d1e5fa}.lesson-body .lesson-lab h2{font-size:1.7rem;line-height:1.25}.lesson-body .lesson-lab>p{font-size:1rem;line-height:1.75;color:var(--reading-muted)}.lesson-body .lesson-panel{padding:20px 0 5px;background:transparent;box-shadow:none}.lesson-body .lesson-panel h3{font-size:1.25rem}.lesson-body .lesson-panel p{font-size:1.05rem;line-height:1.8;color:var(--reading-ink)}.lesson-body .lesson-controls button{font-size:.9rem;line-height:1.4;min-height:46px}.lesson-body .lesson-playback{border-top:1px solid #cedff0;margin-top:15px;padding-top:17px}.lesson-remember{padding:26px 29px;background:#123f69;color:white;border-radius:16px;margin-top:28px}.lesson-remember .eyebrow{color:#b4dcff}.lesson-remember p{font-size:1.15rem;line-height:1.8;margin:10px 0 0}.lesson-practice{padding:38px 0}.lesson-practice h2{font-size:1.7rem;margin:12px 0}.lesson-practice p{font-size:1.08rem;line-height:1.85;color:var(--reading-muted);margin-bottom:22px}.lesson-references{border-top:1px solid #d5e2ef;border-bottom:1px solid #d5e2ef;padding:20px 0}.lesson-references summary{font-size:1rem;cursor:pointer;font-weight:550}.lesson-references>div{display:grid;gap:13px;padding-top:18px}.lesson-references a{font-size:.93rem;color:#0963e8;display:flex;gap:8px}.lesson-related{padding-bottom:50px}.coordinate-controls label{font-size:1rem}.lesson-body .coordinate-diagram{max-width:100%;height:auto}.coordinate-presets{display:flex;flex-wrap:wrap;gap:8px;margin:15px 0}.coordinate-presets button{border:1px solid #a9c9e8;background:white;color:#19456c;border-radius:8px;padding:9px 12px;min-height:44px;font:inherit;font-size:.9rem;cursor:pointer}
@media(max-width:1100px){.explain-card{grid-template-columns:135px 1fr}.explain-card>div{padding:23px 20px}.lesson-layout{grid-template-columns:200px minmax(0,1fr);gap:32px}.lesson-header{gap:30px}}
@media(max-width:800px){.explain-card{grid-template-columns:1fr}.explain-card>img{min-height:0;height:210px}.lesson-header{grid-template-columns:1fr;gap:24px}.lesson-header>figure img{height:300px}.lesson-layout{grid-template-columns:1fr;padding-top:0}.lesson-contents{position:static;grid-template-columns:1fr 1fr;gap:12px;padding-bottom:15px}.lesson-contents>.eyebrow{grid-column:1/-1}.simple-answer{margin-bottom:25px}.lesson-body{max-width:760px}.lesson-header>div>p{max-width:720px}}
@media(max-width:550px){.understand-heading{padding-top:34px;padding-bottom:24px}.understand-heading h1{font-size:2.15rem}.understand-heading>p{font-size:1.07rem}.explain-grid{grid-template-columns:1fr;gap:23px}.explain-card>img{height:215px}.lesson-header{padding-top:24px}.lesson-header h1{font-size:2.15rem}.lesson-header>div>p{font-size:1.08rem;line-height:1.8}.lesson-header>figure img{height:245px}.lesson-contents{grid-template-columns:1fr;gap:11px}.lesson-chapter h2{font-size:1.65rem}.lesson-chapter>p{font-size:1.08rem;line-height:1.85}.simple-answer{padding:22px}.simple-answer p{font-size:1.13rem}.lesson-example figcaption{padding:22px}.lesson-example>img{max-height:285px}.lesson-body .lesson-lab{padding:22px 18px}.lesson-remember{padding:24px}.lesson-body .lesson-controls{gap:7px}.lesson-body .lesson-controls button{font-size:.875rem;padding:10px}.lesson-body .lesson-playback{align-items:flex-start;flex-direction:column}.lesson-body .lesson-playback span{font-size:.875rem}.explain-card>div{padding:24px}.lesson-body .cycle-track{grid-template-columns:1fr 1fr;gap:12px}}
.place-header{align-items:start}.place-header>figure{position:sticky;top:110px;margin-top:36px;min-width:0}.place-header>figure>.photo-credit{position:static;display:block;background:transparent;color:var(--reading-muted);padding:5px 0;border-radius:0;font-size:.75rem}.place-header .text-link{margin-top:20px;font-size:1rem}.place-coordinates{font-size:.875rem;line-height:1.7;color:#587086;margin-top:15px}.look-closer{background:#eef6ff;padding:24px 27px;border-radius:14px;margin:8px 0 34px;border:1px solid #d7e7f5}.look-closer p{font-size:1.09rem;line-height:1.8;margin:12px 0 18px;color:#234767}.look-closer .text-link{font-size:.95rem}.place-history{margin-top:40px;padding-top:15px}.place-history h2{font-size:1.7rem;line-height:1.25;margin-bottom:24px}.place-history .timeline-row h3{font-size:1.1rem}.place-history .timeline-row p{font-size:1rem;line-height:1.75}.place-page .dossier-stats{margin-top:45px;margin-bottom:5px}.place-page .dossier-learning h2{font-size:1.5rem}.place-page .dossier-learning p{font-size:1.03rem;line-height:1.75}.place-page .mini-map{height:480px}.earth-page-heading{padding-top:42px;padding-bottom:32px}.earth-page-heading h1{font-size:clamp(2.2rem,4vw,3.2rem);letter-spacing:-.04em;line-height:1.15;margin:15px 0 20px}.earth-page-heading p{font-size:1.12rem;line-height:1.75;color:var(--reading-muted);max-width:750px}.earth-explanation{display:grid;grid-template-columns:1fr 1.3fr;gap:55px;padding-top:65px;padding-bottom:50px}.earth-explanation h2,.earth-inside h2,.earth-air h2{font-size:2rem;line-height:1.22;letter-spacing:-.03em;margin-top:14px}.earth-explanation p,.earth-inside p,.earth-air p{font-size:1.08rem;line-height:1.85;color:var(--reading-muted);margin-bottom:18px}.earth-reading{padding-top:20px;padding-bottom:45px}.earth-facts{display:grid;grid-template-columns:repeat(3,1fr);gap:28px}.earth-facts article{border-top:2px solid #b6d8f7;padding-top:20px}.earth-fact-number{font-size:1.6rem;color:#0866ef;font-weight:550;display:block;margin-bottom:15px}.earth-facts h3{font-size:1.25rem;margin-bottom:14px;line-height:1.3}.earth-facts p{font-size:1rem;line-height:1.8;color:var(--reading-muted)}.earth-facts a{display:inline-block;color:#0866ef;font-size:.95rem;margin-top:17px}.earth-inside{display:grid;grid-template-columns:1fr 1.3fr;gap:55px;padding-top:45px;padding-bottom:50px}.earth-layers-simple article{border-bottom:1px solid #d9e6f2;margin-bottom:23px;padding-bottom:8px}.earth-layers-simple h3{font-size:1.2rem;line-height:1.4;margin-bottom:12px}.earth-air{background:#edf6ff;border-radius:20px;padding:32px;display:grid;grid-template-columns:1.1fr 1fr;gap:40px;align-items:center}.air-composition{display:flex;gap:5px;flex-wrap:wrap}.air-composition>span:not(.air-other){flex:var(--part) 1 0;background:#96caff;min-height:120px;padding:14px;font-size:.9rem}.air-composition>span:nth-child(2){background:#2b79cf;color:white;min-width:100px}.air-composition strong{display:block;margin-top:12px;font-size:1.5rem}.air-other{font-size:.875rem;color:var(--reading-muted);padding-top:10px;width:100%}.earth-sources{padding-top:28px;padding-bottom:50px;display:flex;gap:25px;flex-wrap:wrap;font-size:.875rem;color:#38607f}
@media(min-width:981px){.site-header #navigation{gap:20px}.site-header #navigation>a,.site-header .learn-nav>summary{font-size:.9rem}.site-header .brand{max-width:155px}}
@media(max-width:800px){.place-header>figure{position:static;margin-top:0}.earth-explanation,.earth-inside,.earth-air{grid-template-columns:1fr;gap:25px}.earth-explanation{padding-top:42px;padding-bottom:25px}.earth-facts{grid-template-columns:1fr;gap:25px}.earth-inside{padding-top:30px}.earth-air{padding:26px}.earth-page-heading h1{font-size:2.15rem}.place-page .mini-map{height:420px}}
@media(max-width:550px){.look-closer{padding:22px}.place-page .mini-map{height:370px}.earth-page-heading{padding-top:28px}.earth-explanation h2,.earth-inside h2,.earth-air h2{font-size:1.8rem}}
.page-intro h1,.journey-intro h1{font-size:clamp(2.2rem,4vw,3.5rem);line-height:1.15;letter-spacing:-.035em}.page-intro .lead,.journey-intro .lead{font-size:1.13rem;line-height:1.8;max-width:780px}.planet-page .article-intro h1{font-size:clamp(2.2rem,4vw,3.25rem);line-height:1.15;max-width:950px}.planet-page .article-intro>p{font-size:1.13rem;line-height:1.8;max-width:780px}.planet-page .reading-section>p{font-size:1.1rem;line-height:1.9}.planet-page .reading-section h2{font-size:1.85rem;line-height:1.3}.planet-page .planet-cover{max-width:720px}.planet-page .observation-question{font-size:1rem;line-height:1.7}.journey-step>p{font-size:1.08rem;line-height:1.85}.journey-step h2{font-size:2rem}.planet-grid .planet-card p{font-size:1rem;line-height:1.75}.directory-hero h1{font-size:clamp(2.2rem,4vw,3.5rem);line-height:1.15}.directory-hero .lead{font-size:1.12rem;line-height:1.8}.reading-body p,.insolite-content p{line-height:1.85}.insolite-content h2{font-size:1.7rem;line-height:1.25}
@media(prefers-reduced-motion:reduce){.explain-card{transition:none}}
@media(max-width:550px){.page-intro h1,.journey-intro h1,.directory-hero h1{font-size:2.25rem}.planet-page .article-intro h1{font-size:2.2rem}.planet-page .reading-section h2{font-size:1.65rem}.journey-step h2{font-size:1.7rem}}