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.textbook-atom{margin:18px 0 22px;padding:6px 12px 18px;background:#fafbf7;border:1px solid #edf0e6;border-radius:16px;text-align:center}.atom-structure-svg{display:block;max-width:100%;height:auto;margin:0 auto;overflow:visible}.atom-nucleus,.atom-shell path{fill:none;stroke:#243f36;stroke-width:2.8;stroke-linecap:round}.atom-structure-svg text{font-family:"Times New Roman","Noto Serif",serif;text-anchor:middle;dominant-baseline:middle;fill:#243f36}.atom-charge{font-size:30px}.atom-electrons{font-size:29px}.atom-outer-shell path{stroke:#177263}.atom-outer-shell .atom-electrons{fill:#177263}.textbook-atom figcaption{font-size:12px;line-height:1.8;color:#647a70}.shell-reading{display:flex;gap:20px;align-items:center;flex-wrap:wrap}.shell-reading-label{font-size:13px;color:#62786d}.shell-reading-values{display:flex;gap:20px;flex-wrap:wrap}.shell-reading-values>span{display:grid;gap:6px;text-align:center}.shell-reading-values strong{font-size:26px;letter-spacing:0;color:#14695b}.shell-reading-values small{font-size:11px;color:#657a6e}.textbook-configuration{font-size:20px;gap:4px}

.element-study{margin-top:22px}.study-heading h2{margin:6px 0}.study-heading p{margin:6px 0}.study-nav{margin:14px 0 18px}.textbook-atom{margin:12px 0 16px;padding:12px}.textbook-atom figcaption{margin-top:10px}