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32px;display:flex;align-items:center;gap:25px;color:#9aa58d;font-size:9px}.footer-brand{color:#6f835c;font-family:var(--mono);font-size:15px;white-space:nowrap}.footer-brand strong{font-family:var(--sans);font-size:11px;margin-left:8px}footer p{margin:0}footer>span{margin-left:auto}dialog{border:1px solid var(--line);border-radius:12px;padding:20px;width:min(850px,90vw);max-height:90vh;color:var(--ink);background:var(--paper)}dialog::backdrop{background:#142d27b0;backdrop-filter:blur(5px)}dialog img{width:100%;border-radius:5px;display:block}dialog>a{display:block;font-size:12px;margin-top:15px;color:#6e8856}.dialog-header{display:flex;justify-content:space-between;align-items:center;margin-bottom:15px}.dialog-header strong{display:block;font-size:14px}.dialog-header span{font-size:10px;color:#8d9a81}.page section{animation:appear .55s both}@keyframes appear{from{opacity:0;transform:translateY(12px)}to{opacity:1;transform:none}}
@media(min-width:1600px){main{padding:0 65px}.hero{gap:65px;padding-top:78px;padding-bottom:60px}.bit-lab{padding:32px}.bit-button{height:51px}.topbar{margin:0 65px}.hero-description{font-size:15px}.hero-actions{margin-top:33px}.hero-caption{margin-top:30px}}
@media(max-width:1200px){.sidebar{width:207px;padding:30px 17px}.page{margin-left:207px}main{padding:0 30px}.topbar{margin:0 30px}.hero{gap:25px;padding-top:42px}.hero-actions{gap:14px;flex-wrap:wrap}.bit-lab{padding:20px}h1{font-size:37px}.lab-result strong{font-size:22px}.lab-result strong.decimal-result{font-size:35px}.lab-footnote{display:block}.lab-footnote span{display:block;margin-top:3px}.converter-layout{grid-template-columns:280px 1fr}.panel{padding:22px}.section-heading h2{font-size:24px}.learning-strip>span:not(.strip-icon):not(.strip-formula){display:none}.shortcut-card{padding:20px}.practice-layout{grid-template-columns:1fr 225px;gap:18px}.hero-description{font-size:12px}.bits{gap:5px}.bit-button{font-size:21px}.base-reference>div{padding:0 12px}.base-reference small{font-size:8px}}
@media(max-width:980px){.sidebar{width:180px;padding:25px 13px}.brand{font-size:15px;gap:9px}.brand small{font-size:7px}.sidebar nav a{font-size:10px;gap:8px}.sidebar-label{margin-top:40px}.page{margin-left:180px}.hero{grid-template-columns:1fr;gap:30px}.hero-copy{padding:5px 0}.hero-description br{display:none}h1{font-size:45px}.hero-caption{margin-top:18px}.bit-lab{max-width:620px}.lab-footnote{display:flex}.hero-actions{margin-top:20px}.hero-copy h1 br{display:none}h1{white-space:normal;font-size:35px}.basics-grid{gap:15px}.panel{padding:18px}.converter-layout{grid-template-columns:235px 1fr;gap:14px}.all-bases{grid-template-columns:1fr}.conversion-answer{font-size:21px}.section-tag{display:none}.place-example{gap:20px}.place-example strong{font-size:35px}.shortcut-grid{grid-template-columns:1fr}.shortcut-card{display:grid;grid-template-columns:25px 1fr 1fr;gap:0 15px}.shortcut-card h3{margin:0 0 10px}.shortcut-card p{grid-column:2;margin:0}.shortcut-example{grid-column:3;grid-row:1/3;margin:0;align-self:center}.shortcut-card small{grid-column:2/4;margin-top:10px}.shortcut-bottom{grid-template-columns:1fr}.practice-layout{grid-template-columns:1fr}.practice-side{display:none}.original-options.long{grid-template-columns:1fr}.base-reference{grid-template-columns:1fr 1fr;gap:20px}.base-reference>div:nth-child(2){border:0}.question-top{padding:18px}.question-card summary{padding:11px 18px}.question-header h3{font-size:12px}footer>span{display:none}}
@media(max-width:700px){html{scroll-padding-top:116px}.sidebar{position:sticky;top:0;inset:auto;width:100%;padding:12px 18px 0;border-right:0;border-bottom:1px solid var(--line);background:#f0f3e9f5;backdrop-filter:blur(15px)}.brand{font-size:15px}.brand small{display:none}.brand-icon{width:29px;height:29px;font-size:16px;border-radius:6px}.brand-icon span{width:15px;height:15px;font-size:11px;bottom:-4px;right:-5px}.sidebar-label,.side-note,.sidebar-bottom{display:none}.sidebar nav{display:flex;overflow:auto;gap:5px;margin:11px -6px 0;scrollbar-width:none;padding-bottom:7px}.sidebar nav a{white-space:nowrap;font-size:10px;padding:7px 9px;gap:5px;border-radius:5px}.sidebar nav a span{font-size:9px}.page{margin-left:0}.topbar{height:46px;margin:0 20px;font-size:9px}.topbar>div{gap:10px}.topbar .text-button{font-size:9px}.offline-label{display:none}main{padding:0 20px}.hero{padding:34px 0 25px;gap:26px}.hero-copy h1 br{display:block}h1{font-size:39px;line-height:1.4;margin-bottom:17px}.eyebrow{font-size:10px;margin-bottom:14px}.hero-description{font-size:12px;line-height:2}.hero-description br{display:block}.hero-actions{gap:24px;margin-top:0}.hero-caption{font-size:9px}.hero-actions .button{padding:10px 20px}.bit-lab{padding:22px 19px;border-radius:9px}.lab-heading{margin-bottom:20px}.bit-lab h2{font-size:17px}.bits{gap:6px}.bit-button{height:41px;font-size:23px}.bit-cell small{font-size:9px}.lab-result strong{font-size:25px}.lab-result strong.decimal-result{font-size:37px}.lab-result small{font-size:8px}.lab-footnote{display:block;font-size:9px}.lab-footnote span{display:inline;margin-left:6px}.learning-strip{padding:11px 13px;gap:9px}.learning-strip strong{font-size:11px}.strip-formula{font-size:10px}.lesson-section{padding-top:43px}.section-heading h2{font-size:23px}.section-intro{font-size:11px;margin-bottom:20px}.basics-grid{grid-template-columns:1fr;gap:14px}.panel{padding:22px}.place-panel .math-line{font-size:12px}.place-example{gap:45px}.place-example strong{font-size:40px}.converter-layout{grid-template-columns:1fr}.all-bases{grid-template-columns:1fr 1fr}.conversion-answer{font-size:24px}.base-reference{gap:15px}.base-reference>div{padding:0 13px}.base-reference small{font-size:8px}.concept-note{font-size:10px}.section-heading{align-items:flex-start}.section-heading .button.small{padding:7px 9px;font-size:9px;margin-top:15px;white-space:nowrap}.question-header{align-items:flex-start;gap:9px}.question-index{margin-top:3px;font-size:10px}.question-header h3{font-size:12px}.original-options{grid-template-columns:1fr 1fr;gap:8px}.original-options button{font-size:11px;padding:9px;gap:8px}.original-options.long{grid-template-columns:1fr}.question-flag{display:none}.question-solution{padding:16px 18px;font-size:11px}.encoding-note{gap:10px;padding:13px;font-size:9px}.shortcut-card{display:block;padding:23px}.shortcut-card h3{margin-top:10px}.shortcut-card h3 br{display:none}.shortcut-card p{font-size:12px}.shortcut-example{margin:15px 0}.shortcut-card small{font-size:10px}.shortcut-grid{gap:14px}.shortcut-bottom{margin-top:14px;gap:14px}.memory-card{padding:20px}.practice-main{padding:20px}.practice-toolbar{gap:8px}.practice-toolbar select{width:150px}.practice-toolbar .badge{font-size:8px;padding:2px 4px}#practice-question{font-size:17px}.practice-stat{font-size:9px;margin-top:18px;padding:4px 8px;white-space:nowrap}.practice-buttons{gap:9px}.practice-buttons .button{font-size:10px;padding:9px 12px}.practice-buttons .text-button{font-size:10px}.practice-section{padding-bottom:35px}footer{gap:12px;flex-wrap:wrap;padding:23px 0}footer p{font-size:8px}.footer-brand{font-size:13px}.footer-brand strong{font-size:10px}dialog{padding:14px;width:94vw}.bit-equation{font-size:10px}.learning-strip .strip-icon{font-size:20px}}
@media(max-width:360px){main{padding:0 14px}.topbar{margin:0 14px}h1{font-size:35px}.bit-lab{padding:18px 13px}.lab-result strong{font-size:22px}.lab-result{gap:9px}.learning-strip .strip-formula{display:none}.practice-toolbar .badge{display:none}.hero-actions{gap:15px}}
.ascii-memory{display:flex;flex-wrap:wrap;gap:8px 23px;background:#edf2e4;border:1px solid #e0e7d5;border-radius:7px;padding:13px 18px;margin-bottom:18px;color:#859675;font-size:11px}.ascii-memory b{color:#526f41;margin-right:5px}.ascii-panel{min-width:0}.ascii-search-row{display:flex;gap:18px;align-items:flex-end}.ascii-search-field{flex:1;max-width:550px;min-width:0}.ascii-search-field label{display:block;font-size:11px;color:#7d8e6e;margin-bottom:7px}.ascii-search-field input{font-size:13px;min-height:43px}.ascii-search-row .button{min-height:43px;white-space:nowrap}.ascii-filters{display:flex;flex-wrap:wrap;gap:7px;margin-top:19px}.ascii-filters button{background:transparent;border:1px solid #dfe5d7;border-radius:5px;padding:6px 11px;font-size:10px;color:#88977a}.ascii-filters button.selected{background:#e5edda;border-color:#cddcba;color:#4a6f36}.ascii-result-count{color:#98a58b;font-size:10px;margin:15px 0 8px}.ascii-table-scroll{max-height:510px;overflow:auto;border:1px solid #e6eadf;border-radius:6px;scrollbar-width:thin;overscroll-behavior:contain}.ascii-table{min-width:665px}.ascii-table th{padding:10px 11px;white-space:nowrap;z-index:1;font-size:10px}.ascii-table td{padding:9px 11px;font-size:12px}.ascii-table .ascii-character{font-size:16px;font-weight:500;color:#3d654b}.ascii-table .ascii-control{font-size:11px;letter-spacing:.02em;color:#8f987b}.ascii-table .ascii-description{font-family:var(--sans);font-size:10px;text-align:left;min-width:135px}.ascii-type{font-family:var(--sans);font-size:9px;color:#94a083;white-space:nowrap}.ascii-examples{display:flex;align-items:center;flex-wrap:wrap;gap:8px;font-size:10px;color:#91a080;margin-top:16px}.ascii-examples button{font-family:var(--mono);font-size:10px;color:#6a854f;background:#f2f6e9;border:1px solid #dfe7d3;border-radius:4px;padding:4px 9px}.ascii-empty{color:#9a855a;background:#fcf7e9;border-radius:5px;padding:14px;font-size:11px;margin:12px 0 0}.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}#ascii .encoding-note a{color:#69834e;text-decoration:underline;text-underline-offset:3px;white-space:nowrap}
@media(max-width:700px){.ascii-memory{font-size:10px;padding:12px 14px;gap:7px 15px}.ascii-panel{padding:17px}.ascii-search-row{gap:10px}.ascii-search-field input{font-size:11px;padding:9px}.ascii-search-row .button{font-size:9px;padding:7px 9px}.ascii-filters{gap:6px}.ascii-filters button{font-size:9px;padding:5px 8px}.ascii-table-scroll{max-height:420px}.ascii-examples{font-size:9px}.ascii-examples>span{width:100%}}
@media print{.ascii-search-row,.ascii-filters,.ascii-panel>.mini-text,.ascii-examples,.ascii-result-count{display:none}.ascii-table-scroll{max-height:none;overflow:visible}.ascii-panel{break-inside:auto;padding:0;border:0}.ascii-table{min-width:0}.ascii-table th{position:static;font-size:8px;padding:5px}.ascii-table td{font-size:9px;padding:4px}.ascii-table .ascii-character{font-size:11px}.ascii-table .ascii-description{font-size:8px;min-width:0}.ascii-table tr{break-inside:avoid}.ascii-table thead{display:table-header-group}.ascii-memory{font-size:9px}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*:before,*:after{animation:none!important;transition:none!important}}
@media print{@page{margin:15mm}body{background:white;color:#22352a;font-size:11px}.sidebar,.topbar,.hero-actions,.hero-caption,.lab-presets,.count-panel,.converter-controls,.textbook-tabs,.original-options,.question-card summary,.practice-section,.section-heading>button,dialog,.side-note{display:none!important}.page{margin:0}main{padding:0;max-width:none}.hero{padding:15px 0;gap:20px}h1{font-size:30px}.bit-lab{print-color-adjust:exact;-webkit-print-color-adjust:exact}.hero-description{font-size:11px}.hero-copy h1 br{display:block}.hero{grid-template-columns:1fr 1fr}.lab-heading,.lab-footnote{display:none}.bits{gap:3px}.bit-button{height:30px;font-size:19px}.lab-result strong{font-size:20px}.lab-result strong.decimal-result{font-size:27px}.learning-strip{margin-bottom:15px}.lesson-section{padding-top:24px}.section-heading h2{font-size:22px}.panel,.question-card,.shortcut-card{break-inside:avoid}.basics-grid,.converter-layout{display:block}.base-reference{grid-template-columns:repeat(4,1fr)}.question-solution{display:block!important;background:#fafcf5}.question-top{padding:13px 18px}.question-header{margin:0}.question-card details{display:block}.shortcut-grid{grid-template-columns:repeat(3,1fr)}.shortcut-card{display:block;padding:16px}.shortcut-card h3{font-size:14px;margin:10px 0}.shortcut-example{margin:12px 0}.shortcut-bottom{grid-template-columns:1fr 1fr}.table-scroll{max-height:none;overflow:visible}.question-flag{display:none}.section-intro{margin-bottom:15px}.conversion-output{break-inside:avoid}.concept-note{display:block}footer{padding:15px 0}}

/* Tablet and phone reading: local fonts, generous touch targets and readable text. */
.touch-nav-hint,.ascii-scroll-hint{display:none}
@media(max-width:1024px){
  html{scroll-padding-top:140px}
  .sidebar{position:sticky;top:0;inset:auto;width:100%;padding:13px 24px 0;border-right:0;border-bottom:1px solid var(--line);background:#f0f3e9f5;backdrop-filter:blur(15px)}
  .brand{font-size:16px;gap:11px}.brand small{display:none}.brand-icon{width:30px;height:30px;font-size:16px}.brand-icon span{width:16px;height:16px;font-size:12px}
  .touch-nav-hint{display:block;position:absolute;right:24px;top:21px;font-size:11px;color:#87967a}
  .sidebar-label,.side-note,.sidebar-bottom{display:none}
  .sidebar nav{display:flex;overflow-x:auto;overscroll-behavior-x:contain;gap:7px;margin:11px -5px 0;padding-bottom:8px;scrollbar-width:thin}
  .sidebar nav a{white-space:nowrap;flex-shrink:0;font-size:12px;min-height:44px;padding:10px 13px;gap:7px}.sidebar nav a span{font-size:11px}
  .page{margin-left:0}.topbar{margin:0 24px}main{padding:0 24px}
  .hero{grid-template-columns:1fr;gap:26px}.hero-copy h1 br{display:block}.bit-lab{max-width:680px;width:100%}
  .hero-description,.section-intro{font-size:14px;line-height:1.95}.eyebrow{font-size:12px}.hero-caption{font-size:11px}
  .button,.quiet-link,.text-button{font-size:13px}.button{min-height:44px}.text-button{min-height:44px;display:inline-flex;align-items:center;justify-content:center}
  .round-button{width:44px;height:44px;font-size:21px}.bit-button{min-height:48px}
  .lab-heading{font-size:12px}.bit-lab>p{font-size:13px}.bit-cell small{font-size:12px}.bit-equation{font-size:13px;min-height:43px}.lab-result small{font-size:11px}.lab-presets{font-size:12px;gap:8px;flex-wrap:wrap}.lab-presets button{min-height:44px;min-width:44px;font-size:13px}.lab-footnote{font-size:11px}
  .learning-strip strong{font-size:13px}.strip-formula{font-size:12px}
  .panel-title{font-size:14px}.segmented button{font-size:13px;min-height:44px}.counter-actions{font-size:14px}.count-note,.note-block{font-size:13px;line-height:1.95}.place-panel>p{font-size:14px}.place-example span{font-size:12px}
  .mini-text{font-size:12px!important}.base-reference strong{font-size:14px}.base-reference>div>span:not(.base-number){font-size:12px}.base-reference small{font-size:11px}.concept-note{font-size:13px}.concept-note summary{min-height:48px;line-height:1.9}
  .converter-layout{grid-template-columns:minmax(260px,.8fr) minmax(0,1.2fr)}.converter-controls label{font-size:13px}input,select{min-height:44px;font-size:16px}.base-selects select{font-size:13px}.swap-button{min-height:44px;min-width:32px}.preset-list>span{font-size:12px}.preset-list button{font-size:12px;min-height:44px}.step-title,.step-explanation,#conversion-steps{font-size:13px}.math-expansion{font-size:13px}.division-rows{font-size:13px}.all-bases small{font-size:11px}
  .textbook-tabs button{font-size:13px;min-height:44px}.question-header h3{font-size:15px}.question-index{font-size:12px}.original-options button{font-size:14px;min-height:48px}.question-card summary{font-size:13px;min-height:48px}.question-solution{font-size:14px}.original-feedback,.caution{font-size:13px}.question-solution a{font-size:13px;display:inline-block;padding:7px 0}.encoding-note{font-size:12px;line-height:1.95}
  .shortcut-card p,.shortcut-card small,.memory-card p{font-size:13px}.shortcut-card h3{font-size:18px}.shortcut-example,.shortcut-example b{font-size:14px}
  .ascii-memory{font-size:13px}.ascii-search-field label{font-size:13px}.ascii-search-field input{font-size:16px}.ascii-search-row .button{font-size:12px}.ascii-filters button{font-size:12px;min-height:44px}.ascii-result-count{font-size:12px}.ascii-table th{font-size:12px;padding:11px}.ascii-table td{font-size:13px;min-height:44px;padding:12px 10px}.ascii-table .ascii-description{font-size:12px}.ascii-type{font-size:11px}
  .ascii-scroll-hint{display:block;color:#8a997b;font-size:12px;margin:0 0 10px}.ascii-table th:first-child{position:sticky;left:0;z-index:3;background:#edf3e3}.ascii-table td:first-child{position:sticky;left:0;z-index:2;background:#fff;box-shadow:2px 0 0 #e5eadc}.ascii-table tr:nth-child(even) td:first-child{background:#fafbf7}
  .ascii-examples{font-size:12px}.ascii-examples button{font-size:13px;min-height:44px;min-width:60px}.ascii-empty{font-size:13px}
  .practice-toolbar label,.practice-toolbar select{font-size:12px}.practice-toolbar select{width:190px}.practice-buttons .button,.practice-buttons .text-button{font-size:13px;min-height:44px}#practice-question small{font-size:12px}.practice-options label{font-size:14px!important;min-height:48px}.practice-options input{width:20px;height:20px;min-height:20px}.practice-feedback:not(:empty),.hint-box{font-size:14px}.practice-stat{font-size:12px}
}
@media(max-width:700px){
  main{padding:0 18px}.sidebar{padding-left:18px;padding-right:18px}.touch-nav-hint{right:18px;font-size:10px}.topbar{margin:0 18px}
  .hero{padding-top:28px}.hero-description br{display:none}.hero-actions{gap:18px}.hero-caption{gap:8px;font-size:10px}.bit-lab{padding:22px 18px}.lab-result strong{font-size:24px}.lab-result strong.decimal-result{font-size:36px}.lab-result small{font-size:10px}.lab-footnote{line-height:1.9}
  .learning-strip{flex-wrap:wrap}.strip-formula{margin-left:30px}.section-heading h2{font-size:23px}.section-heading .button.small{font-size:11px;min-height:44px;margin-top:8px}
  .panel{padding:20px}.converter-layout{grid-template-columns:1fr}.base-reference{grid-template-columns:1fr 1fr}.base-reference small{font-size:10px;line-height:1.8}.original-options{grid-template-columns:1fr 1fr}.original-options.long{grid-template-columns:1fr}.question-top{padding:17px}.question-header h3{font-size:14px}
  .encoding-note{display:block;font-size:12px}.encoding-note>span{display:block;margin-bottom:5px}.ascii-panel{padding:16px}.ascii-search-row{flex-wrap:wrap;gap:8px}.ascii-search-field{flex-basis:100%}.ascii-search-row .button{min-height:44px}.ascii-filters button{font-size:12px;padding:7px 10px}.ascii-examples>span{width:100%}.ascii-memory{font-size:12px;gap:7px}
  .practice-toolbar{flex-wrap:wrap}.practice-toolbar select{flex:1;min-width:170px}.practice-toolbar .badge{margin-left:0}.practice-buttons{gap:10px}.practice-buttons .text-button{margin-left:0}.practice-stat{font-size:11px}.textbook-tabs{gap:6px}.textbook-tabs button{font-size:12px;padding:8px 12px}
  input,select,#practice-input{font-size:16px}.base-selects select{font-size:16px;padding:6px 3px}.all-bases small{font-size:10px}
}
@media(max-width:560px){.bits{grid-template-columns:repeat(4,minmax(0,1fr));gap:12px}.bit-button{height:48px;font-size:26px}.bit-cell{gap:5px}.lab-heading{margin-bottom:18px}.lab-result{margin-top:7px}.hero-caption{flex-wrap:wrap}.base-selects{gap:5px}.original-options button{padding:11px 9px}}
@media(pointer:coarse) and (min-width:1025px){button,.button,select{min-height:44px}.sidebar nav a{min-height:44px}.round-button{width:44px;height:44px}.bits{gap:5px}.bit-button{height:44px}.original-options button{font-size:14px}.section-intro{font-size:14px}.ascii-table td{padding:12px 10px;font-size:13px}}
@media print{.touch-nav-hint,.ascii-scroll-hint{display:none!important}#ascii .ascii-panel{break-inside:auto}.ascii-table td:first-child{position:static;box-shadow:none}.ascii-table th:first-child{position:static}}