/* Compact tool layout; element-family colours are functional labels. */
:root{--ink:#202d34;--muted:#6b7982;--teal:#125b63;--paper:#f7f9fa;--line:#dce3e7;--metal:#c5e3ee;--main:#dce9bd;--transition:#d4deef;--halogen:#f2dfba;--noble:#e8d6eb;--inner:#cfe4dd;--good:#18734d;--bad:#b5413c;font-family:-apple-system,BlinkMacSystemFont,"Segoe UI","PingFang SC","Microsoft YaHei",sans-serif;color:var(--ink);background:var(--paper);font-synthesis:none}
*{box-sizing:border-box}body{margin:0}button,input,select{font:inherit;color:inherit}button,select{cursor:pointer}button{border:0;background:transparent}button:disabled{opacity:.4;cursor:not-allowed}a{color:inherit}button,input,select,a,[tabindex]{-webkit-tap-highlight-color:transparent}button:focus-visible,input:focus-visible,select:focus-visible,a:focus-visible,[tabindex]:focus-visible{outline:2px solid #dc9d39;outline-offset:2px}[hidden]{display:none!important}
.page{max-width:1500px;padding:0 24px;margin:auto}.site-header{height:60px;display:flex;align-items:center;justify-content:space-between;border-bottom:1px solid var(--line);margin-bottom:18px}.brand{font-size:20px;font-weight:650;letter-spacing:-.5px;text-decoration:none}.quiet{border-radius:5px;padding:7px 10px;font-size:12px;font-weight:500}.quiet:hover{background:#e7edef}#wrong-count{display:inline-block;min-width:21px;text-align:center;padding:2px 4px;background:#e7edef;border-radius:4px;margin-left:5px;font-size:11px}
.settings{display:flex;align-items:flex-start;gap:20px;flex-wrap:wrap;background:white;border:1px solid var(--line);border-radius:8px;padding:15px 16px;margin-bottom:14px}.setting-group{display:flex;flex-direction:column;gap:6px}.setting-label{font-size:11px;color:var(--muted)}.segmented{display:flex;gap:2px;padding:3px;border-radius:5px;background:#f0f3f4;height:36px}.segmented button{padding:0 15px;font-size:12px;border-radius:3px}.segmented button.active{background:var(--teal);color:white}.segmented button:not(.active):hover{background:#e1e9eb}.count-control{display:flex;align-items:center;gap:5px;height:36px}.count-control button{width:28px;height:28px;font-size:17px;background:#f0f3f4;border-radius:4px}.count-control input{width:44px;padding:4px 0;text-align:center;border:0;border-bottom:1px solid #ccd8dc;background:transparent;font-size:17px;font-weight:600;appearance:textfield;-moz-appearance:textfield}.count-control input::-webkit-inner-spin-button{appearance:none}.setting-group small{font-size:10px;line-height:1.4;color:var(--muted)}.setting-group select{height:36px;border:1px solid var(--line);background:white;border-radius:5px;font-size:12px;padding:0 28px 0 10px;min-width:115px}.pool-group select{min-width:180px}.primary,.secondary{height:36px;border-radius:5px;padding:0 18px;font-size:12px;font-weight:600;display:inline-flex;align-items:center;justify-content:center}.primary{background:var(--teal);color:white}.primary:hover{background:#0e4850}.secondary{border:1px solid #ccd8dc;background:white}.secondary:hover{background:#edf2f3}.start-button{margin-top:21px;margin-left:auto;min-width:80px}.selection-note{display:flex;align-items:center;justify-content:space-between;font-size:12px;margin-bottom:12px;gap:10px}.selection-note>div{display:flex;gap:2px}
.worksheet{border:1px solid var(--line);border-radius:8px;background:white;overflow:hidden}.worksheet-head{display:flex;align-items:center;justify-content:space-between;gap:12px;padding:12px 16px;border-bottom:1px solid #e9eef0}h2{margin:0;font-size:13px;font-weight:600}.progress-wrap{display:flex;align-items:center;gap:12px;font-size:11px;color:var(--muted);font-variant-numeric:tabular-nums}.progress-track{width:70px;height:3px;overflow:hidden;border-radius:3px;background:#e3eaec}.progress-track i{display:block;height:100%;background:var(--teal);width:0}.table-scroll{overflow-x:auto;padding:10px 12px 14px;scrollbar-color:#b9c9cd #f2f5f6}.periodic-table{display:grid;grid-template-columns:22px repeat(18,minmax(52px,1fr));grid-template-rows:18px repeat(7,82px) 10px repeat(2,82px);gap:4px;min-width:1080px}.group-label,.period-label{display:flex;align-items:center;justify-content:center;color:var(--muted);font-size:10px}.period-label{font-size:11px}.cell{--family:var(--main);position:relative;border:1px solid #d0dcdf;border-top:3px solid var(--family);border-radius:4px;min-width:0;display:flex;flex-direction:column;align-items:center;padding:2px 4px;background:white;overflow:hidden}.cell.metal{--family:var(--metal)}.cell.transition{--family:var(--transition)}.cell.halogen{--family:var(--halogen)}.cell.noble{--family:var(--noble)}.cell.inner{--family:var(--inner)}.cell .atomic-number{align-self:flex-start;height:12px;line-height:12px;margin:0 0 1px 1px;font-size:10px;color:var(--muted)}.cell.active-cell{background:color-mix(in srgb,var(--family) 22%,white)}.cell.inactive{background:#f5f7f8;border-color:#e7edef}.cell.inactive .atomic-number{color:#b4c0c5}.cell.inactive:after{content:'·';font-size:23px;color:#cad4d8;margin-top:7px}.cell input{display:block;width:100%;min-width:0;padding:0 1px;text-align:center;border:0;border-bottom:1px solid #cad7db;background:transparent;border-radius:0;height:26px;line-height:26px;font-size:18px;font-weight:600}.cell .name-input{font-size:12px;font-weight:400;height:22px;line-height:22px}.cell .name-input.english{font-size:10px}.cell input::placeholder{color:#a5b4ba;font-size:10px;font-weight:400}.cell input:focus{background:white;outline:2px solid var(--teal);outline-offset:0;border-radius:2px}.cell input:disabled{opacity:1;-webkit-text-fill-color:currentColor}.cell .right-field{color:var(--good);border-bottom-color:#8ac4a5}.cell .wrong-field{color:var(--bad);background:#ffefec;border-bottom-color:#d9948a}.grade-status{font-size:9px;line-height:10px;margin-top:2px;white-space:nowrap}.cell.correct{border-color:#90bdaa;background:#edf7f0}.cell.correct .grade-status{color:var(--good)}.cell.incorrect{border-color:#dda89f;background:#fff5f2}.cell.incorrect .grade-status{color:var(--bad)}.cell.pick:hover{border-color:var(--teal);background:#e7f1ed}.pick-label{margin-top:14px;font-size:20px;color:#9dadb2}.cell.pick.selected{background:#e5f0e6;border:2px solid var(--teal);padding-top:3px}.cell.pick.selected .pick-label{color:var(--teal)}.cell.pick.inactive:after{display:none}.f-placeholder{display:flex;flex-direction:column;align-items:center;justify-content:center;gap:6px;border:1px dashed #cbdcd6;background:#f0f5f3;border-radius:4px;font-size:10px;color:#688279}.series-label{align-self:center;text-align:center;color:var(--muted);font-size:10px}.worksheet-bottom{border-top:1px solid #edf2f3;padding:10px 16px}.legend{display:flex;flex-wrap:wrap;gap:8px 16px}.legend span{display:flex;align-items:center;gap:5px;font-size:10px;color:var(--muted)}.legend i{width:8px;height:8px;display:inline-block;border-radius:2px}.legend .metal{background:var(--metal)}.legend .main{background:var(--main)}.legend .transition{background:var(--transition)}.legend .halogen{background:var(--halogen)}.legend .noble{background:var(--noble)}.legend .inner{background:var(--inner)}
.action-bar{display:flex;justify-content:flex-end;padding:12px 0 16px}.actions{display:flex;gap:8px}.actions button{min-width:80px}.results{display:flex;align-items:center;gap:18px;justify-content:space-between;padding:16px 18px;border:1px solid #cadcd2;background:#f2f7f4;border-radius:8px;margin-bottom:14px}.result-score{font-size:30px;font-weight:650;line-height:1;font-variant-numeric:tabular-nums}.result-score span{font-size:14px}.result-message{flex:1}.result-message p{font-size:11px;color:var(--muted);line-height:1.6;margin:5px 0 0}.result-actions{display:flex;gap:6px}.mistake-details{padding-top:18px}.mistake-details h2{margin-bottom:10px}#mistake-list{display:grid;grid-template-columns:repeat(auto-fill,minmax(225px,1fr));gap:8px}.mistake-row{display:flex;gap:12px;border:1px solid var(--line);background:white;border-radius:5px;padding:12px}.mistake-symbol{font-size:24px;font-weight:600;min-width:35px}.mistake-row strong{display:block;font-size:12px;font-weight:600}.mistake-row small{font-size:10px;color:var(--muted)}.mistake-row p{margin:4px 0 0;font-size:11px;color:var(--bad);line-height:1.6;overflow-wrap:anywhere}
footer{border-top:1px solid var(--line);padding:12px 0 20px;display:flex;justify-content:space-between;align-items:center;gap:12px;flex-wrap:wrap;font-size:10px;color:var(--muted)}footer a{text-underline-offset:3px}.visit-stats{display:flex;align-items:center;flex-wrap:wrap;gap:10px 16px}.visit-stats strong{font-size:12px;font-weight:600;color:var(--ink);font-variant-numeric:tabular-nums}.visit-status:empty{display:none}.footer-meta{display:flex;gap:16px;flex-wrap:wrap}.footer-meta>div{display:flex;gap:10px}
dialog{max-width:950px;width:calc(100% - 32px);max-height:85vh;border:1px solid var(--line);border-radius:8px;padding:20px;color:var(--ink);background:white}dialog::backdrop{background:#20384055}.dialog-top{display:flex;justify-content:space-between;align-items:flex-start;gap:16px;margin-bottom:16px}.dialog-top h2{font-size:17px}.dialog-top p{font-size:11px;color:var(--muted);margin:6px 0 0}.reference-grid{display:grid;grid-template-columns:repeat(auto-fill,minmax(135px,1fr));gap:6px}.reference-item{display:flex;align-items:center;gap:10px;border:1px solid var(--line);border-radius:4px;padding:10px}.reference-item .symbol{font-size:21px;font-weight:600;min-width:28px}.reference-item small,.english-name{font-size:10px;color:var(--muted)}.reference-item strong{font-size:12px;display:block;font-weight:500}.toast{position:fixed;bottom:22px;left:50%;transform:translateX(-50%);background:var(--ink);color:white;padding:10px 18px;border-radius:5px;font-size:12px;z-index:10;max-width:90vw;text-align:center}
@media(max-width:1100px){.settings{gap:15px}.start-button{margin-left:0}.results{flex-wrap:wrap}.result-actions{margin-left:auto}}
@media(max-width:700px){.page{padding:0 12px}.site-header{height:52px;margin-bottom:12px}.brand{font-size:19px}.settings{display:grid;grid-template-columns:minmax(0,1fr) minmax(0,1fr);gap:13px 12px;padding:12px;margin-bottom:12px}.mode-group{grid-column:1/3}.segmented button{flex:1;padding:0 10px}.count-group{grid-column:1;grid-row:2}.pool-group{grid-column:2;grid-row:2}.language-group{grid-column:1;grid-row:3}.setting-group select{min-width:0;width:100%;max-width:100%;padding-right:16px}.pool-group small{font-size:9px;overflow-wrap:anywhere}.start-button{grid-column:2;grid-row:3;margin:21px 0 0}.worksheet-head{padding:10px 12px}.progress-track{width:44px}.table-scroll{padding:8px 8px 12px}.worksheet-bottom{padding:9px 12px}.legend{gap:6px 12px}.legend span{font-size:9px}.actions{display:grid;grid-template-columns:1fr 1fr;width:100%}.action-bar{padding:12px 0}.results{gap:12px;padding:13px}.result-score{font-size:28px}.result-actions{width:100%;margin:0}.result-actions button{flex:1;padding:0 10px}.result-message h2{font-size:12px}.result-message p{font-size:10px}footer{align-items:flex-start;gap:10px}.footer-meta{width:100%;justify-content:space-between}.visit-stats{gap:8px 14px}dialog{padding:16px}.reference-grid{grid-template-columns:repeat(2,minmax(0,1fr))}.reference-item{gap:7px;padding:8px}.reference-item .symbol{font-size:19px}.english-name{font-size:9px;overflow-wrap:anywhere}}
@media(prefers-reduced-motion:reduce){*{scroll-behavior:auto!important}}