:root{--navy:#071f2c;--navy2:#103748;--paper:#f6f4ed;--ink:#10252d;--muted:#607078;--sea:#138b83;--foam:#d9f2ed;--line:#d5ddd9;--coral:#d86348;color-scheme:light;font-family:Inter,ui-sans-serif,system-ui,sans-serif;background:var(--paper);color:var(--ink)}*{box-sizing:border-box}html{scroll-behavior:smooth}body{margin:0}a{color:inherit}.skip{position:absolute;left:-9999px}.skip:focus{left:1rem;top:1rem;background:#fff;padding:.7rem;z-index:99}.shell{max-width:1180px;margin:auto;padding:0 24px}.topbar{background:var(--navy);color:#e7f3f2;font-size:.78rem;padding:.55rem 0}.site-head{background:#f6f4edf5;border-bottom:1px solid var(--line);position:sticky;top:0;z-index:20}.nav{height:76px;display:flex;align-items:center;gap:30px}.brand{display:flex;align-items:center;gap:12px;text-decoration:none;font-weight:800;letter-spacing:-.02em}.brand img{width:42px}.navlinks{display:flex;gap:24px;margin-left:auto;font-weight:650;font-size:.9rem}.navlinks a{text-decoration:none}.nav-cta,.button{display:inline-flex;align-items:center;justify-content:center;padding:.82rem 1.1rem;border-radius:6px;background:var(--sea);color:#fff;text-decoration:none;font-weight:750;border:0;cursor:pointer}.button.secondary{background:transparent;color:var(--navy);border:1px solid #789099}.hero{background:var(--navy);color:#fff;padding:78px 0 64px;position:relative;overflow:hidden}.hero:after{content:"";position:absolute;width:540px;height:540px;border:1px solid #1e5365;border-radius:50%;right:-160px;top:-260px;box-shadow:0 0 0 70px #0b2b39,0 0 0 71px #1e5365}.eyebrow{text-transform:uppercase;letter-spacing:.15em;font-size:.75rem;font-weight:800;color:#66d6ca}.hero-grid{display:grid;grid-template-columns:1.2fr .8fr;gap:70px;position:relative;z-index:1}.hero h1{font-family:Georgia,serif;font-size:clamp(2.6rem,6vw,5.2rem);line-height:.98;letter-spacing:-.055em;max-width:820px;margin:.3em 0}.hero 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42px}.chart-preview:after{content:"54° 12.0′ N  ·  010° 18.0′ E";position:absolute;bottom:16px;left:16px;background:#071f2c;color:#fff;padding:9px 12px;font:12px monospace}.page-hero{padding:65px 0 45px;background:#e7efeb;border-bottom:1px solid var(--line)}.page-hero h1{font:clamp(2.4rem,5vw,4.4rem)/1 Georgia,serif;max-width:900px;margin:.3em 0}.content{max-width:820px}.content p,.content li{line-height:1.7;color:#43565d}.notice{padding:18px;border-left:4px solid var(--coral);background:#fff3e9;margin:25px 0}.footer{background:#061923;color:#d0dadd;padding:50px 0}.footer-grid{display:grid;grid-template-columns:2fr 1fr 1fr;gap:30px}.footer a{display:block;margin:.6rem 0;color:#d0dadd;text-decoration:none}.quiz{background:#fff;border:1px solid var(--line);padding:28px;border-radius:10px;margin-top:30px}.answers{display:grid;gap:10px;margin:20px 0}.answer{padding:15px;text-align:left;border:1px solid var(--line);background:#fff;border-radius:6px;cursor:pointer}.answer[aria-pressed=true]{border-color:var(--sea);background:var(--foam)}.feedback{padding:15px;background:var(--foam);border-radius:6px}.chart-app{display:grid;grid-template-columns:220px 1fr;min-height:590px;border:1px solid #35535e;background:#e3eeea;border-radius:12px;overflow:hidden;margin-top:24px}.tools{background:#092936;color:#fff;padding:18px}.tools button{display:block;width:100%;text-align:left;padding:12px;margin:7px 0;border:1px solid #486973;background:#123945;color:#fff;border-radius:5px}.tools button.active{background:#46b8ac;color:#062229}.canvas{position:relative;overflow:hidden;background-image:radial-gradient(circle at 75% 35%,#c4d7ce 0 40px,transparent 41px),linear-gradient(#6d9a9555 1px,transparent 1px),linear-gradient(90deg,#6d9a9555 1px,transparent 1px);background-size:auto,50px 50px,50px 50px;cursor:crosshair}.canvas svg{width:100%;height:100%}.readout{position:absolute;right:12px;bottom:12px;background:#082631;color:#fff;padding:10px;font:12px monospace}.toolbar-result{margin-top:12px;background:#d9f2ed;color:#153e3c;padding:12px;border-radius:5px}.rtl{direction:rtl}@media(max-width:800px){.navlinks{display:none}.hero-grid,.feature-grid,.footer-grid{grid-template-columns:1fr}.instrument{display:none}.cards{grid-template-columns:1fr}.stats{grid-template-columns:1fr 1fr}.hero{padding-top:50px}.chart-app{grid-template-columns:1fr}.tools{display:grid;grid-template-columns:1fr 1fr}.tools h3{grid-column:1/-1}.canvas{min-height:430px}}@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}