:root{
  --ink:#eef7fb;--muted:#9eb3c1;--night:#06131f;--panel:#0b1d2b;--line:#254050;
  --orange:#ffad33;--cyan:#62d6ff;--red:#ff6b5f;--green:#62d49c;
  --cell:58px;--gap:5px;
  font-family:Inter,ui-sans-serif,system-ui,-apple-system,BlinkMacSystemFont,"Segoe UI",sans-serif;
  color-scheme:dark
}
*{box-sizing:border-box}
html{background:var(--night);scroll-behavior:smooth}
body{margin:0;min-width:320px;color:var(--ink);background:
  radial-gradient(circle at 8% 0%,rgba(30,104,140,.22),transparent 28rem),
  radial-gradient(circle at 88% 20%,rgba(255,173,51,.08),transparent 24rem),var(--night)}
button,input{font:inherit}
button{color:inherit}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip:rect(0,0,0,0);white-space:nowrap;border:0}
.masthead{max-width:1440px;margin:auto;padding:28px 28px 18px;position:relative;border-bottom:1px solid rgba(255,255,255,.08)}
.brand{position:absolute;right:28px;top:30px;color:var(--orange);font-weight:700;letter-spacing:.03em}
.eyebrow,.kicker{font-size:.76rem;letter-spacing:.18em;font-weight:800;color:var(--cyan)}
h1{font-family:Georgia,"Times New Roman",serif;font-size:clamp(2.15rem,4.5vw,4.75rem);line-height:.98;max-width:980px;margin:.55rem 0 0;font-weight:500;letter-spacing:-.035em}
.subtitle{font-family:Georgia,"Times New Roman",serif;font-style:italic;font-size:clamp(1.15rem,2vw,1.7rem);color:#bdd0da;margin:.55rem 0 0}
main{max-width:1440px;margin:auto;padding:18px 28px 44px}
.controls{display:flex;gap:16px;justify-content:flex-start;align-items:center;margin:4px 0 14px}
.view-switch{display:flex;border:1px solid var(--line);padding:3px;background:#071725;border-radius:10px}
.mode{border:0;background:transparent;padding:9px 14px;border-radius:7px;font-size:.88rem;font-weight:700;cursor:pointer;color:var(--muted)}
.mode.active{background:#18364a;color:#fff;box-shadow:inset 0 0 0 1px #2c5268}
.legend{display:flex;flex-wrap:wrap;gap:7px 14px;margin:0 0 14px;min-height:24px}
.legend-item{display:inline-flex;align-items:center;gap:6px;font-size:.76rem;color:#aebfc8}
.swatch{width:10px;height:10px;border-radius:2px;background:var(--swatch);box-shadow:0 0 9px color-mix(in srgb,var(--swatch),transparent 35%)}
.workspace{display:grid;grid-template-columns:minmax(0,1fr) 340px;gap:18px;align-items:start}
.table-shell,.detail-panel,.method{border:1px solid rgba(108,150,172,.24);background:rgba(8,25,37,.8);box-shadow:0 18px 55px rgba(0,0,0,.19)}
.table-shell{padding:14px;border-radius:14px;min-width:0}
.table-scroll{overflow-x:auto;padding-bottom:5px}
.periodic-table{display:grid;grid-template-columns:repeat(18,var(--cell));grid-template-rows:repeat(9,var(--cell));gap:var(--gap);min-width:1129px}
.element{position:relative;grid-column:var(--col);grid-row:var(--row);border:1px solid color-mix(in srgb,var(--element-color),#fff 10%);background:color-mix(in srgb,var(--element-color),#081925 80%);border-radius:6px;padding:4px;cursor:pointer;overflow:hidden;text-align:left;transition:transform .15s,border-color .15s,filter .15s,opacity .15s;isolation:isolate}
.element::after{content:"";position:absolute;inset:auto -18px -24px auto;width:46px;height:46px;border-radius:50%;background:var(--element-color);filter:blur(15px);opacity:.2;z-index:-1}
.element:hover,.element:focus-visible{transform:translateY(-2px);border-color:#fff;outline:none;z-index:2}
.element.selected{outline:2px solid #fff;outline-offset:1px}
.element.dimmed{opacity:.15;filter:saturate(.2)}
.atomic{display:block;font-size:.58rem;color:#adc2ce;line-height:1}
.symbol{display:block;font-family:Georgia,serif;font-size:1.35rem;line-height:1.02;margin-top:2px;font-weight:700}
.name{display:block;font-size:.55rem;white-space:nowrap;overflow:hidden;text-overflow:ellipsis;color:#c1d1d8}
.dg-dot{position:absolute;right:4px;top:4px;width:5px;height:5px;border-radius:50%;background:var(--orange);box-shadow:0 0 7px var(--orange)}
.series-labels{display:grid;grid-template-columns:repeat(18,var(--cell));gap:var(--gap);min-width:1129px;margin-top:calc(-2 * var(--cell) - var(--gap));pointer-events:none;color:#66808e;font-size:.58rem;letter-spacing:.08em;text-transform:uppercase}
.series-labels span:first-child{grid-column:1/3;transform:translateY(9px)}
.series-labels span:last-child{grid-column:1/3;transform:translateY(calc(var(--cell) + 13px))}
.table-note{font-size:.78rem;color:#849dac;margin:12px 2px 0}
.detail-panel{position:sticky;top:16px;border-radius:14px;min-height:530px;padding:22px;overflow:hidden}
.empty-state{min-height:480px;display:flex;flex-direction:column;justify-content:center;align-items:flex-start}
.empty-state h2,.detail-panel h2,.method h2{font-family:Georgia,serif;font-size:2rem;font-weight:500;margin:.35rem 0 .6rem}
.empty-state p:last-child,.detail-copy{color:var(--muted);line-height:1.55}
.coverage{display:grid;grid-template-columns:repeat(3,1fr);gap:8px;width:100%;margin-top:18px}
.coverage span{border-top:1px solid var(--line);padding-top:9px;color:#7893a1;font-size:.68rem;line-height:1.25}
.coverage b{display:block;color:#e7f1f5;font:600 1.12rem/1.2 Georgia,serif;margin-bottom:2px}
.orbit-mark{width:84px;height:84px;border:1px solid #366178;border-radius:50%;position:relative;margin-bottom:25px}
.orbit-mark::before{content:"";position:absolute;inset:16px;border:1px solid #285167;border-radius:50%;transform:rotate(65deg) scaleX(.45)}
.orbit-mark span{position:absolute;width:12px;height:12px;border-radius:50%;background:var(--orange);left:35px;top:35px;box-shadow:0 0 20px var(--orange)}
.detail-head{display:grid;grid-template-columns:92px 1fr;gap:16px;padding-bottom:16px;border-bottom:1px solid var(--line)}
.big-symbol{height:92px;border:1px solid var(--accent);border-radius:10px;background:color-mix(in srgb,var(--accent),transparent 88%);padding:8px;position:relative}
.big-symbol b{font:700 3rem/1 Georgia,serif;display:block;margin-top:14px}
.big-symbol span{position:absolute;top:7px;left:8px;font-size:.75rem;color:#b8cbd5}
.detail-panel h2{margin:8px 0 2px}
.element-family{color:#9eb5c1;font-size:.85rem}
.origin-card{margin:17px 0;padding:13px;border-left:3px solid var(--accent);background:rgba(255,255,255,.035)}
.origin-card .label{font-size:.68rem;letter-spacing:.12em;color:#90a8b5;font-weight:800}
.origin-card strong{display:block;margin:4px 0;font-size:1rem}
.origin-card p{font-size:.83rem;line-height:1.45;color:#a9bdc7;margin:0}
.dg-section h3{font-size:.78rem;letter-spacing:.12em;text-transform:uppercase;margin:19px 0 9px;color:#d8e5ea}
.dg-list{display:grid;gap:8px}
.dg-entry{border:1px solid #294353;border-radius:8px;padding:10px;background:#0b2130}
.dg-top{display:flex;gap:8px;align-items:baseline}
.un{font-weight:800;color:var(--orange);white-space:nowrap}
.psn{font-size:.83rem;font-weight:700;line-height:1.3}
.dg-meta{display:flex;flex-wrap:wrap;gap:5px;margin-top:7px}
.pill{font-size:.68rem;border:1px solid #355364;border-radius:999px;padding:2px 6px;color:#a9c0cc}
.relation{color:var(--cyan)}
.no-entries{border:1px dashed #365160;padding:14px;border-radius:8px;color:#99afba;font-size:.83rem;line-height:1.45}
.notice{font-size:.73rem;color:#7893a1;margin-top:14px;line-height:1.45}
.method{margin-top:18px;border-radius:14px;padding:24px;display:grid;grid-template-columns:280px 1fr;gap:30px}
.method h2{margin-bottom:0}
.method-grid{display:grid;grid-template-columns:repeat(3,1fr);gap:24px;color:#9fb4bf;line-height:1.55;font-size:.86rem}
.method-grid p{margin:0}.method-grid strong{color:#e3edf1}
.sources{grid-column:1/-1;margin:0;padding-top:18px;border-top:1px solid var(--line);color:#7f99a7;font-size:.78rem;line-height:1.5}
.sources a{color:var(--cyan);text-underline-offset:3px}
footer{max-width:1440px;margin:auto;border-top:1px solid rgba(255,255,255,.08);padding:20px 28px 30px;display:flex;justify-content:space-between;color:#718b99;font-size:.76rem}
@media(max-width:1050px){.workspace{grid-template-columns:1fr}.detail-panel{position:relative;top:0;min-height:auto}.empty-state{min-height:240px}.method{grid-template-columns:1fr}.method-grid{grid-template-columns:repeat(3,1fr)}}
@media(max-width:700px){.masthead{padding:22px 16px 16px}.brand{position:static;margin-bottom:18px;font-size:.82rem}.eyebrow{margin-top:2px}main{padding:14px 12px 32px}.controls{align-items:stretch;flex-direction:column}.view-switch{width:100%}.mode{flex:1}.legend{gap:6px 10px}.workspace{gap:12px}.table-shell{padding:9px}.method{padding:18px;gap:20px}.method-grid{grid-template-columns:1fr;gap:15px}footer{padding:18px 16px;gap:8px;flex-direction:column}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important;transition:none!important}}