[hidden]{display:none!important}.chemistry-main{padding-top:64px;padding-bottom:64px}.chemistry-heading{display:flex;justify-content:space-between;align-items:center;gap:30px;margin-bottom:48px}.chemistry-heading h1{font-size:clamp(28px,4.4vw,64px);line-height:1.2;letter-spacing:.11em;font-weight:400;margin:20px 0}.intro{font-size:clamp(16px,1.6vw,21px);color:#b9bbc0}.privacy{flex-shrink:0;border-left:1px solid #303030;padding-left:24px;font-size:11px;letter-spacing:.12em}.privacy span{display:block;letter-spacing:0;margin-top:12px;color:#b9bbc0}.chemistry-layout{display:grid;grid-template-columns:1.05fr 1fr;gap:18px;align-items:start}.chem-panel{border:1px solid #303030;background:#080808;padding:28px;min-width:0}.chem-panel h2,.small-label{font-size:11px;font-weight:400;letter-spacing:.18em;margin:0 0 24px}.small-label{margin:24px 0 12px}.chem-panel button,.chem-panel textarea,.chem-panel select{font:inherit;color:#eee;border:1px solid #686868;background:#080808;border-radius:0}.chem-panel button{min-height:44px;padding:12px 16px;cursor:pointer;font-size:12px}.chem-panel button:hover{background:#eee;color:#000}.chem-panel button:disabled{opacity:.55;cursor:wait}.chem-panel textarea{width:100%;box-sizing:border-box;resize:vertical;min-height:108px;padding:16px;font-size:20px;line-height:1.6}.chem-panel select{width:100%;padding:12px;min-height:46px;margin-top:12px;font-size:12px}.chem-panel label{font-size:13px}.hint,.footnote{color:#b5b5bb;font-size:12px;line-height:1.8;overflow-wrap:anywhere}.equation-preview{border:1px solid #303030;padding:16px;font-size:20px;line-height:1.7;min-height:66px;white-space:pre-wrap;overflow-wrap:anywhere}.examples{display:grid;grid-template-columns:repeat(3,1fr);gap:8px}.examples button{padding:10px 6px}details{margin-top:24px;border:1px solid #444}summary{padding:14px;font-size:12px;cursor:pointer;min-height:44px;box-sizing:border-box}summary:hover{background:#171717}.details-body{padding:0 16px 16px}.check-label{display:flex;gap:10px;align-items:center;line-height:1.7;margin-top:14px}.check-label input{width:18px;height:18px;accent-color:#fff}.chem-panel .primary{display:block;width:100%;background:#eee;color:#000;font-weight:bold;font-size:14px;margin-top:24px}.chem-panel .primary:hover{background:#ccc}.actions{display:flex;justify-content:space-between;margin-top:8px}.chem-panel .text-button{border:0;text-decoration:underline;background:transparent;padding-left:0}.chem-panel .text-button:hover{color:#bbb}.chem-panel :focus-visible{outline:2px solid white;outline-offset:4px}#error{font-size:13px;line-height:1.7;overflow-wrap:anywhere}#error:not(:empty){border-left:2px solid #fff;padding:12px;background:#171717}#status{font-size:12px;color:#b9bbc0;line-height:1.7;margin-top:-8px}.balanced-label{font-size:24px;margin:24px 0 16px}#balanced-equation{font-size:clamp(22px,2.2vw,34px);line-height:1.7;white-space:normal;overflow-wrap:anywhere}#balanced-equation strong{font-weight:800}.copy-actions{display:flex;gap:12px;margin:24px 0}.copy-actions button{flex:1}.table-wrap{overflow:auto}table{width:100%;border-collapse:collapse;font-size:12px}td,th{border:1px solid #333;padding:12px;text-align:left;font-weight:400}#step-list{padding:0 24px 8px 36px;font-size:12px;line-height:1.9;overflow-wrap:anywhere}#step-list li{padding:8px 0}#step-list pre{font:inherit;white-space:pre-wrap;margin:8px 0;color:#b9bbc0}.result-note{margin-top:24px}#empty-result{padding:36px 0 64px;color:#aaa}#empty-result h3{font-size:19px;color:#eee;font-weight:400}#empty-result p{font-size:13px;line-height:1.9}.empty-symbol{font-size:60px;line-height:1}.footnote{margin-top:28px}.footnote a{display:inline-block;margin-left:12px;text-decoration:underline}.notice{border:1px solid #555;padding:20px}@media(max-width:850px){.chemistry-layout{grid-template-columns:1fr}.chemistry-heading{align-items:flex-start;flex-direction:column}.chemistry-main{padding-top:32px}.chemistry-heading{margin-bottom:28px}.privacy{margin-top:0}.chem-panel{padding:22px}}@media(max-width:400px){.chem-panel{padding:16px}.chemistry-heading h1{font-size:25px;letter-spacing:.06em}.copy-actions{flex-direction:column}td,th{padding:9px 6px}.chem-panel textarea{font-size:17px}.examples{grid-template-columns:repeat(2,1fr)}}
.sr-only{position:absolute;width:1px;height:1px;padding:0;margin:-1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap;border:0}
#task{margin-bottom:18px}#prediction-options{margin:18px 0;padding:16px;border:1px solid #333}#prediction-notice{border-left:2px solid #ddd;padding:0 0 0 18px;margin:24px 0;font-size:13px;line-height:1.8;overflow-wrap:anywhere}#prediction-title{font-size:20px;font-weight:400;line-height:1.5}#prediction-source{text-decoration:underline;font-size:12px}.prediction-examples{margin-top:16px}