/* Elementa 1.1: a crisp scientific reading surface. No external fonts or trackers. */
:root{--accent:#2548d8;--navy:#11244b;--muted:#52627b;--line:#dce3ef;--surface:#f3f6fb}
body{background:var(--surface);color:var(--navy);font-family:'Segoe UI',Arial,sans-serif}
[dir=rtl] body{font-family:Tahoma,'Segoe UI',Arial,sans-serif;line-height:1.85}
h1,h2,h3{color:var(--navy)}.eyebrow{color:var(--accent);font-size:12px;letter-spacing:.12em}
.header{padding:20px 3.5%;border-bottom:1px solid var(--line);gap:30px;box-shadow:0 3px 16px #152d5705}
.brand{font-size:25px;letter-spacing:-1.1px;color:var(--navy)}.brand-mark{background:var(--navy);color:#fff;border:0;border-radius:9px;width:37px;height:39px}.brand-dot{color:var(--accent)}
.header nav{gap:26px}.header nav a{color:#55637c;font-size:14px}.header nav a[aria-current]{color:var(--accent)}.header nav a[aria-current]:after{background:var(--accent)}
.header-actions{gap:18px}.subscribe-nav{font-size:14px;font-weight:600;border:1px solid #ced8f5;padding:7px 13px;border-radius:7px;color:#2442ba;background:#f3f6ff}.subscribe-nav:hover{background:#e8eefe}.compare-nav b{background:#e9edfc;color:#2945bb}
.intro{padding:38px 0 29px;gap:30px}.intro h1{font-size:clamp(34px,3.35vw,54px);max-width:890px;letter-spacing:-.045em;line-height:1.1}.intro-sub{font-size:18px;color:var(--muted)}.intro-meta{min-width:180px}.intro-meta strong{color:var(--accent);font-size:54px}.intro-meta p,.meta-rule{display:none}.intro-meta strong span{font-size:12px;color:var(--muted)}
.explorer{border:1px solid #d6dfec;border-radius:18px;box-shadow:0 16px 48px #17376808;padding:24px;background:#fff}
.search{background:#f6f8fc;border:1px solid #d4ddea;border-radius:9px;min-height:48px}.search:focus-within{outline:2px solid #3158da;outline-offset:1px}.search input{font-size:15px}.toolbar select{font-size:14px;border-color:#d4ddea;min-height:48px;border-radius:9px}.view-switch{background:#edf1f9;border-radius:9px}.view-switch button{font-size:14px}.view-switch button[aria-pressed=true]{color:var(--accent);box-shadow:0 2px 6px #18347613}
.group-labels{color:#58677f}.element{border:1px solid #ffffff70;border-radius:7px;box-shadow:inset 0 1px 0 #ffffff65}.element strong{font-weight:700;font-size:26px}.element-name{font-size:12px}.element-mass{font-size:11px;opacity:1}.element:hover,.element:focus-visible{transform:translateY(-3px) scale(1.035);box-shadow:0 8px 18px #19365a25}.element.dim{opacity:.18}
.table-feature{gap:20px;padding-bottom:25px}.feature-symbol{border:0;box-shadow:0 8px 25px #17366c0c;background:#edf3ff}.table-feature h2{font-size:30px}.table-feature .eyebrow{font-size:12px}.table-feature p{font-size:15px;color:var(--muted)}.text-link,.breadcrumbs a{color:var(--accent)}.data-note{color:#52627b;font-size:12px}.table-meta,#results-count{color:#405779}.text-button{font-size:13px;color:#3350bc}.legend button{color:#435776}
.below-grid{gap:20px;margin:24px 0 44px}.learning-banner{background:var(--navy);color:white;border-color:var(--navy);border-radius:16px;padding:30px}.learning-banner h2{color:white}.learning-banner .eyebrow{color:#a8c7ff}.learning-banner p{color:#cad7ec}.banner-icon{background:#ffffff16}.earth-banner{border-color:#d5deed;border-radius:16px}.earth-banner p{color:#52627b}.earth-banner>svg{color:#9db3e6}
.dark{background:var(--accent)}.dark:hover{background:#1833a6}.button{border-radius:8px;font-size:14px}.outline{border-color:#cbd5e7}.outline:hover{background:#eef2fd}
.detail-hero{border-color:#d7e0ee;border-radius:20px;padding:40px;box-shadow:0 12px 45px #213e6206;position:relative;overflow:hidden}.detail-hero:before{content:'';position:absolute;inset-block:0;inset-inline-start:0;width:5px;background:var(--ink)}.big-element{border-radius:12px;box-shadow:inset 0 1px 0 #ffffff88}.detail-heading h1{margin-bottom:14px}.detail-heading>p:not(.eyebrow,.other-name){color:#52627b;line-height:1.7}.fact dt{font-size:14px;color:#5b6980}.fact dd{color:var(--navy)}.facts-grid .fact{border-color:#dce3ef;border-radius:12px;padding:22px}.article-section p,.reading>p,.reading section p{color:#4d5d75}.article-section{border-color:#dae1ec}.aside-card{background:#eaf0ff;border-color:#dbe4fa;border-radius:12px}.aside-card p{color:#4d6082}.note{background:#eef3ff;border-inline-start:3px solid #496bd6;color:#30496f;border-radius:0 8px 8px 0}
.lesson-card,.production-card{border-color:#d9e1ef;border-radius:14px;box-shadow:0 4px 16px #19365a04}.lesson-index{color:#5f7ac6}.lesson-card:hover{border-color:#748ee0}.quiz-box{background:#eaf0ff;border-color:#d7e1f7}.resource:hover{background:#edf2ff}.page-intro p:last-child{color:#52627b}.bar-track span{background:#4d70d3}
footer{align-items:start;gap:40px;border-color:var(--line);padding:36px 3.5%;background:white}.footer-links{max-width:570px;gap:14px 24px;color:#465c7d;font-size:14px}.footer-links a:hover{text-decoration:underline}.footer-note{color:#52627b;white-space:nowrap}footer p{color:#52627b;max-width:280px}.toast{background:var(--navy)}
.join-layout{display:grid;grid-template-columns:1fr 1fr;gap:9%;align-items:center;max-width:1150px;margin:65px auto 80px}.join-copy h1{font-size:clamp(38px,4.5vw,66px);line-height:1.09;letter-spacing:-.045em}.join-copy .lead{font-size:20px;line-height:1.7;color:#52627b;max-width:480px}.join-benefits{list-style:none;padding:0;margin:30px 0}.join-benefits li{padding:13px 0;border-bottom:1px solid #dce3ef;font-size:16px;color:#30496d;display:flex;gap:12px}.join-benefits li:before{content:'✓';color:var(--accent);font-weight:700}
.join-card{background:white;border:1px solid #d9e1f0;box-shadow:0 20px 70px #2138650b;border-radius:20px;padding:36px}.join-card h2{font-size:27px;margin:10px 0}.join-card>p{font-size:15px;color:#52627b}.form-kicker{font-size:12px;color:var(--accent);letter-spacing:.12em;font-weight:700}.join-card form{margin-top:26px}.join-card form>label:not(.check-row){display:block;font-size:14px;font-weight:600;margin:18px 0 8px}.join-card input[type=email],.join-card select{width:100%;min-height:48px;padding:12px 14px;border:1px solid #cbd7e9;border-radius:8px;background:#fbfcff;color:#142b50;font:inherit;font-size:16px}.check-row{display:flex;align-items:flex-start;gap:10px;font-size:14px;line-height:1.7;margin:20px 0}.check-row input{width:18px;height:18px;flex:0 0 18px;margin:4px 0 0;accent-color:var(--accent)}.check-row a{color:#2146bc;text-decoration:underline;text-underline-offset:3px}.join-submit{width:100%;justify-content:space-between;margin-top:6px;padding:14px 18px}.form-feedback:empty{display:none}.form-feedback{padding:14px;border-radius:8px;background:#eaf0ff;font-size:14px;margin:14px 0 0;color:#244680}.join-card button:disabled{opacity:.55;cursor:not-allowed}
.policy-page{max-width:940px;margin:55px auto 70px}.policy-heading{border-bottom:1px solid #cfdbea;padding-bottom:24px;margin-bottom:28px}.policy-heading h1{font-size:clamp(34px,4.5vw,56px);line-height:1.2}.policy-date{font-size:13px;color:#62738d;margin:0}.policy-heading .lead{font-size:19px;color:#52627b}.policy-sections section{display:grid;grid-template-columns:45px minmax(0,1fr);gap:20px;padding:27px 0;border-bottom:1px solid #dce3ef}.policy-sections .section-number{padding-top:3px;color:var(--accent);font-size:15px;font-weight:650}.policy-sections h2,.contact-grid h2{font-size:23px;letter-spacing:-.02em}.policy-sections p,.contact-grid p{font-size:16px;line-height:1.9;color:#4d607d;margin:0}.policy-bottom{display:flex;justify-content:space-between;gap:24px;margin-top:35px;color:var(--accent);font-size:14px}.policy-page>button{margin-top:25px}.contact-grid{display:grid;grid-template-columns:1fr 1fr;gap:24px}.contact-grid section{padding:28px;background:white;border:1px solid #dce3ef;border-radius:14px}.operator-contact{overflow-wrap:anywhere}.form-trap{position:absolute!important;left:-10000px!important;width:1px;height:1px;overflow:hidden}
[dir=rtl] .join-copy h1,[dir=rtl] .policy-heading h1{letter-spacing:0;line-height:1.5}[dir=rtl] .join-copy h1{font-size:clamp(34px,3.8vw,54px)}[dir=rtl] .intro h1{font-size:clamp(32px,3.8vw,54px);line-height:1.5}[dir=rtl] .element{line-height:1.25}[dir=rtl] .element-name{line-height:1.5}
@media(max-width:1100px){.header{gap:20px}.header nav{gap:16px}.header-actions{gap:12px}.join-layout{gap:5%}.join-card{padding:28px}.footer-note{display:none}.intro-meta{min-width:130px}}
@media(max-width:760px){.header{padding:15px 5%;gap:16px}.header nav{gap:12px}.header nav a{font-size:13px}.brand{font-size:22px}.brand-mark{width:33px;height:36px}.header-actions{gap:12px}.subscribe-nav{font-size:12px;padding:5px 9px}.compare-nav{gap:4px}.language svg{display:none}.intro{padding:28px 0 22px}.intro h1{font-size:35px;line-height:1.15}.intro-sub{font-size:16px}.explorer{padding:15px 12px;border-radius:14px}.search input{font-size:14px}.toolbar select{font-size:12px;min-height:43px}.view-switch button{font-size:12px}.periodic.cards .element{min-height:128px;border-radius:10px}.periodic.cards .element strong{font-size:35px}.periodic.cards .element-name{font-size:13px}.periodic.cards .element-mass{font-size:12px}.detail-hero{padding:25px;gap:20px}.detail-heading h1{margin-bottom:10px}.hero-facts .fact dt{font-size:12px}.detail-heading .button{font-size:13px}.facts-grid .fact{padding:15px}.join-layout{grid-template-columns:1fr;gap:30px;margin:32px 0 45px}.join-copy h1{font-size:39px}.join-copy .lead{font-size:18px}.join-benefits{margin:18px 0}.join-benefits li{font-size:15px;padding:9px 0}.join-card{padding:25px 21px;border-radius:16px}.join-card h2{font-size:25px}.policy-page{margin:32px 0 45px}.policy-heading h1{font-size:35px}.policy-sections section{grid-template-columns:25px minmax(0,1fr);gap:12px}.policy-sections h2{font-size:22px}.contact-grid{grid-template-columns:1fr}.contact-grid section{padding:22px}footer{padding:30px 5%;gap:25px}.footer-links{font-size:13px;gap:12px 18px}.policy-bottom{flex-direction:column;gap:12px}.note{font-size:14px}.data-note{font-size:12px}}
@media(max-width:390px){.header{gap:14px}.header-actions{gap:8px}.brand{font-size:20px}.compare-nav svg{width:17px}.language select{max-width:70px}}
@media print{body{background:white}.subscribe-nav,.join-layout,.policy-bottom{display:none}.detail-hero,.explorer{box-shadow:none}.intro h1{font-size:28px}}

.brand-mark{display:inline-flex;align-items:center;justify-content:center;font-family:Arial,sans-serif;font-size:30px;line-height:1}.brand{font-size:23px}.header{gap:22px}.header nav{gap:22px}@media(max-width:760px){.brand{font-size:19px}.brand-mark{font-size:27px;width:30px;height:33px}.header-actions{gap:8px}.subscribe-nav{padding:5px 7px}.compare-nav span{display:none}.header{column-gap:9px}}