@font-face{font-family:'Inter';font-style:normal;font-weight:100 900;font-display:swap;src:url(/assets/fonts/inter-latin.woff2) format('woff2');unicode-range:U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+2074,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD}@font-face{font-family:'Inter';font-style:normal;font-weight:100 900;font-display:swap;src:url(/assets/fonts/inter-latinext.woff2) format('woff2');unicode-range:U+0100-02BA,U+02BD-02C5,U+02C7-02CC,U+02CE-02D7,U+02DD-02FF,U+0304,U+0308,U+0329,U+1D00-1DBF,U+1E00-1E9F,U+1EF2-1EFF,U+2020,U+20A0-20AB,U+20AD-20C0,U+2113,U+2C60-2C7F,U+A720-A7FF}:root{--brand: #b3122b;--brand-ink: #8a0e21;--brand-tint: #fbe4e7;--navy: #101114;--accent: #f1b8bf;--ink: #1a1c1f;--muted: #5f6470;--line: #ececec;--bg: #ffffff;--bg-soft: #f7f7f7;--card: #ffffff;--maxw: 120rem;--radius: 16px;--radius-sm: 12px;--shadow: 0 6px 24px -12px rgba(16, 17, 20, .16);--shadow-lift: 0 18px 44px -16px rgba(16, 17, 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ease}.btn:hover{background:var(--brand-ink);border-color:var(--brand-ink);color:#fff;text-decoration:none;transform:translateY(-1px);box-shadow:var(--shadow)}.btn-outline{background:#fff;color:var(--brand)}.btn-outline:hover{background:var(--brand-tint);color:var(--brand-ink);border-color:var(--brand)}.nav-cta{padding-block:.8rem 1.5rem}.nav-cta.btn{padding:.9rem 1.8rem}.layout{display:grid;grid-template-columns:1fr 30rem;gap:4rem;align-items:start;padding-block:2.8rem 5.6rem;min-height:60vh}.sidebar{position:sticky;top:8rem;display:grid;gap:1.6rem}.side-card{background:var(--card);border:1px solid var(--line);border-radius:var(--radius);padding:1.6rem;box-shadow:var(--shadow)}.side-h{font-family:var(--font-head);font-size:1.248rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);margin:0 0 1.12rem}.side-topics{list-style:none;margin:0;padding:0}.side-topics li+li{border-top:1px dotted var(--line)}.side-topics a{display:block;padding:.8rem 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1rem;text-align:left}.prose th{background:var(--bg-soft);font-family:var(--font-head)}.prose a{font-weight:700}:root{--c-alkali-metal:#ef9a9a;--c-alkaline-earth-metal:#ffcc80;--c-transition-metal:#90caf9;--c-post-transition-metal:#80cbc4;--c-metalloid:#c5e1a5;--c-nonmetal:#a5d6a7;--c-halogen:#fff59d;--c-noble-gas:#4dd0e1;--c-lanthanide:#f48fb1;--c-actinide:#f8bbd0;--c-unknown:#cfd8dc}.ptable-scroll{overflow-x:auto;padding-bottom:1rem}.ptable{display:grid;grid-template-columns:repeat(18,minmax(4.6rem,1fr));gap:.4rem;min-width:92rem}.el{grid-row:auto;border:1px solid rgba(0,0,0,.12);border-radius:7px;padding:.3rem .2rem .35rem;background:var(--bg-soft);color:#14181f;cursor:pointer;text-align:left;font-family:var(--font-body);display:grid;gap:0;line-height:1.05;transition:transform .1s ease,box-shadow .1s ease,opacity .1s ease}.el[data-cat=alkali-metal]{background:var(--c-alkali-metal)}.el[data-cat=alkaline-earth-metal]{background:var(--c-alkaline-earth-metal)}.el[data-cat=transition-metal]{background:var(--c-transition-metal)}.el[data-cat=post-transition-metal]{background:var(--c-post-transition-metal)}.el[data-cat=metalloid]{background:var(--c-metalloid)}.el[data-cat=nonmetal]{background:var(--c-nonmetal)}.el[data-cat=halogen]{background:var(--c-halogen)}.el[data-cat=noble-gas]{background:var(--c-noble-gas)}.el[data-cat=lanthanide]{background:var(--c-lanthanide)}.el[data-cat=actinide]{background:var(--c-actinide)}.el[data-cat=unknown]{background:var(--c-unknown)}.el:hover,.el:focus{transform:scale(1.12);z-index:5;box-shadow:0 8px 18px -6px #00000073;outline:none}.el-n{font-size:1.05rem;font-weight:700;opacity:.8}.el-s{font-size:1.9rem;font-weight:800;font-family:var(--font-head)}.el-name{font-size:.95rem;font-weight:700;overflow:hidden;text-overflow:ellipsis;white-space:nowrap}.el-mass{font-size:.92rem;opacity:.75}.ptable.is-filtering .el.dim{opacity:.18}.ptable-fmark{display:grid;place-items:center;border:1px dashed var(--line);border-radius:7px;color:var(--muted);font-weight:800;font-size:1.2rem}.ptable-legend{display:flex;flex-wrap:wrap;gap:.6rem;margin:1.5rem 0}.leg{display:inline-flex;align-items:center;gap:.5rem;border:1px solid var(--line);background:#fff;border-radius:999px;padding:.45rem 1rem;font-weight:700;font-size:1.35rem;cursor:pointer;color:var(--ink)}.leg:hover{border-color:var(--brand)}.leg.on{border-color:var(--ink);box-shadow:inset 0 0 0 1px var(--ink)}.swatch{width:1.4rem;height:1.4rem;border-radius:5px;border:1px solid rgba(0,0,0,.15)}.swatch[data-cat=alkali-metal]{background:var(--c-alkali-metal)}.swatch[data-cat=alkaline-earth-metal]{background:var(--c-alkaline-earth-metal)}.swatch[data-cat=transition-metal]{background:var(--c-transition-metal)}.swatch[data-cat=post-transition-metal]{background:var(--c-post-transition-metal)}.swatch[data-cat=metalloid]{background:var(--c-metalloid)}.swatch[data-cat=nonmetal]{background:var(--c-nonmetal)}.swatch[data-cat=halogen]{background:var(--c-halogen)}.swatch[data-cat=noble-gas]{background:var(--c-noble-gas)}.swatch[data-cat=lanthanide]{background:var(--c-lanthanide)}.swatch[data-cat=actinide]{background:var(--c-actinide)}.swatch[data-cat=unknown]{background:var(--c-unknown)}.ptable-detail{margin:1.5rem 0}.el-card{display:flex;align-items:center;gap:1.4rem;border:1px solid var(--line);border-radius:var(--radius);padding:1.2rem 1.6rem;background:var(--card);box-shadow:var(--shadow);min-height:8rem}.el-card[data-cat]{border-left:8px solid var(--line)}.el-card[data-cat=alkali-metal]{border-left-color:var(--c-alkali-metal)}.el-card[data-cat=alkaline-earth-metal]{border-left-color:var(--c-alkaline-earth-metal)}.el-card[data-cat=transition-metal]{border-left-color:var(--c-transition-metal)}.el-card[data-cat=post-transition-metal]{border-left-color:var(--c-post-transition-metal)}.el-card[data-cat=metalloid]{border-left-color:var(--c-metalloid)}.el-card[data-cat=nonmetal]{border-left-color:var(--c-nonmetal)}.el-card[data-cat=halogen]{border-left-color:var(--c-halogen)}.el-card[data-cat=noble-gas]{border-left-color:var(--c-noble-gas)}.el-card[data-cat=lanthanide]{border-left-color:var(--c-lanthanide)}.el-card[data-cat=actinide]{border-left-color:var(--c-actinide)}.el-card[data-cat=unknown]{border-left-color:var(--c-unknown)}.el-card-sym{font-family:var(--font-head);font-weight:800;font-size:3.4rem;min-width:5rem;text-align:center;color:var(--ink)}.el-card-body{font-size:1.6rem}.el-card-body .muted,.muted{color:var(--muted)}

@media(max-width:60rem){.main-nav a{padding:1.1rem .6rem}.az a{width:3.8rem;height:3.8rem}}