/* finesse · register=product · shell=calculation-notebook · A=sage+forest · B=humanist+math · C=notebook+notes · D=feedback-only · E=quiet-paper · SOUL=6 SPECTACLE=2 DENSITY=7 */
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@media(hover:none){.result-copy,.row-remove{opacity:1}}
@media(min-width:1400px){.workspace{padding-top:52px}.expression-notebook{min-height:298px}.key{min-height:50px}.workspace-heading{margin-bottom:31px}.site-footer{margin-top:52px}}
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@media(max-width:820px){.workspace{max-width:710px;padding-top:30px}.site-header{height:75px;padding:0 28px}.brand-note{display:none}.workspace-grid{display:block}.side-notes{display:none}.below-calculator{max-width:none}.workspace-heading h1{font-size:27px}.workspace-heading{margin-bottom:23px}.site-footer{max-width:654px;margin:30px auto 0;flex-wrap:wrap}.expression-notebook{min-height:267px}.key{min-height:49px}.keypad-toolbar{gap:12px}.tabs{gap:18px}.keypad-options .icon-button{width:30px}.keypad{gap:7px}.keypad-area{padding:13px 18px 0}.site-header nav{gap:20px}.brand-en{display:none}.support-button{min-height:44px}}
@media(max-width:600px){.site-header{height:70px;padding:0 20px}.brand img{width:33px;height:33px}.brand-name{font-size:22px}.site-header nav{gap:13px}.help-button{width:36px;min-height:44px}.help-button>span:last-child{display:none}.support-button{font-size:11px;padding:0 12px;min-height:38px}.workspace{padding:27px 16px 0}.workspace-heading{margin-bottom:20px}.page-label{font-size:9px;letter-spacing:.7px;margin-bottom:7px}h1,.workspace-heading h1{font-size:25px;letter-spacing:.5px}.privacy-note{display:none}.calculator{border-radius:17px}.calculator-topbar{min-height:58px;padding:7px 13px 7px 17px}.saved-label{font-size:9px;margin-right:2px}.calculator-title h2{font-size:12px}.calculator-title{gap:7px}.calculator-title svg{width:16px;height:16px}.notebook-caption{padding:0 17px 10px;font-size:9px}.expression-notebook{min-height:225px;padding-top:15px}.expression-row{padding:8px 10px 8px 12px;grid-template-columns:23px minmax(0,1fr) 26px;min-height:74px}.expression-input{font-size:17px}.expression-input::placeholder{font-size:12px}.result-value{font-size:23px}.result-copy{opacity:1}.expression-list{max-height:230px}.add-expression{margin:8px 12px 10px;min-height:35px;font-size:10px}.keypad-area{padding:8px 12px 0}.keypad-toolbar{gap:4px;margin-bottom:11px}.tabs{gap:12px}.tabs button{font-size:11px;min-height:40px}.keypad-options{gap:1px}.angle-toggle{padding:2px}.angle-toggle button{padding:0 5px;font-size:9px;min-height:27px}.toolbar-divider{display:none}.keypad-options .icon-button{width:25px;min-height:34px}.keypad-options .icon-button svg{width:14px;height:14px}.keypad,.keypad.functions-layout,.keypad.variables-layout{grid-template-columns:repeat(5,minmax(0,1fr));gap:7px}.key{min-height:45px;font-size:21px;border-radius:8px}.key.number{font-size:20px}.key.function{font-size:17px}.key.small-label{font-size:12px}.key.span-two{grid-column:span 1}.key.enter{font-size:12px}.keypad-footer{min-height:43px;font-size:9px;gap:3px}.keypad-footer .text-button{font-size:9px;gap:4px}.below-calculator{padding:8px 1px;gap:6px}.below-calculator>span{font-size:9px;gap:3px;max-width:66%;line-height:1.7}.below-calculator .text-button{font-size:9px;gap:2px}.below-calculator svg{width:10px;height:10px}.site-footer{margin:24px 17px 0;padding:18px 0 calc(17px + env(safe-area-inset-bottom));justify-content:center;text-align:center;gap:0}.site-footer>span{width:100%;font-size:9px}.site-footer .text-button{font-size:9px}.site-footer>div{gap:12px}.help-list>div{grid-template-columns:120px minmax(0,1fr);gap:10px}.help-list>div>span{font-size:11px}dialog{padding:20px;max-height:calc(100dvh - 32px)}.dialog-header h2{font-size:19px}.dialog-lead{font-size:12px}.row-remove{opacity:1}.support-button:focus-visible{outline-offset:3px}}
@media(max-width:360px){.workspace{padding-left:11px;padding-right:11px}.site-header{padding:0 15px}.keypad-area{padding-left:9px;padding-right:9px}.tabs{gap:9px}.tabs button{font-size:10px}.keypad-options .icon-button{width:22px}.angle-toggle button{padding:0 4px}.keypad{gap:6px}.expression-input::placeholder{font-size:11px}.below-calculator>span{max-width:60%}.notebook-caption>span:last-child{font-size:8px}.help-list>div{grid-template-columns:105px minmax(0,1fr)}}
@media(max-width:600px){.support-button{min-height:44px}.icon-button{width:44px;min-width:44px;min-height:44px}.keypad-toolbar{flex-wrap:wrap;row-gap:3px}.tabs{width:100%;gap:20px}.tabs button{min-width:44px;min-height:44px}.keypad-options{width:100%;justify-content:flex-end;gap:3px}.angle-toggle{margin-right:auto}.angle-toggle button{min-width:44px;min-height:38px}.keypad-options .icon-button{width:44px;min-width:44px;min-height:44px}.expression-row{grid-template-columns:23px minmax(0,1fr) 44px}.row-remove{width:44px;min-height:44px}.result-copy{width:32px;min-width:32px;min-height:32px;position:relative}.result-copy::after{content:'';position:absolute;inset:-6px}.add-expression{min-height:44px}.angle-toggle button{position:relative}.angle-toggle button::after{content:'';position:absolute;inset:-3px 0}.keypad-footer .text-button{min-height:44px}}
/* Language controls keep their native names; mathematical notation always reads left to right. */
.site-header nav{margin-left:0;margin-inline-start:auto;gap:20px}.language-picker{display:inline-flex;align-items:center;gap:5px;min-height:44px;color:var(--ink-3)}.language-picker svg{width:16px;height:16px}.language-picker select{font:inherit;color:var(--ink-2);font-size:12px;border:0;background:var(--white-space);min-height:44px;max-width:117px;cursor:pointer;padding:0 3px;outline-offset:2px}.language-picker select option{color:var(--ink);background:var(--canvas)}.brand-name{letter-spacing:.1px;font-size:23px}.note-intro h2,.note-intro p{white-space:pre-line}.example{text-align:start}.expression-list,.expression-input,.result-line,.keypad,.angle-toggle,.example-formula,.help-list code,.help-list kbd{direction:ltr}.expression-input{text-align:left}.result-line{justify-content:flex-start}.help-list code,.help-list kbd{unicode-bidi:isolate}.keypad-toolbar{flex-wrap:wrap;row-gap:5px}.keypad-footer{flex-wrap:wrap;column-gap:8px}.keypad-footer .text-button{flex-shrink:0}.notebook-caption{gap:12px}.notebook-caption>span:last-child{text-align:end}.below-calculator>span{min-width:0;line-height:1.7}.site-footer>div{flex-wrap:wrap;justify-content:center}.site-footer{flex-wrap:wrap}.site-footer .text-button{max-width:100%}.help-list>div{grid-template-columns:135px minmax(0,1fr)}[dir=rtl] .variables-status{direction:rtl;text-align:right}[dir=rtl] .notebook-caption,[dir=rtl] .aside-title{direction:rtl}[dir=rtl] .topbar-actions{direction:rtl}[dir=rtl] .brand-note{border-left:0;border-inline-start:1px solid var(--line-strong);padding-left:0;padding-inline-start:26px}.side-notes{overflow-wrap:anywhere}.notebook-caption>span:first-child{white-space:nowrap}
@media(max-width:1050px){.brand-note{display:none}.site-header nav{gap:16px}.brand-name{font-size:21px}}
@media(max-width:820px){.site-header nav{gap:15px}.keypad-toolbar{row-gap:5px}.brand-name{font-size:21px}.workspace-heading h1{font-size:26px}}
@media(max-width:600px){.site-header{padding:0 15px;gap:8px}.brand{gap:8px}.brand-name{font-size:20px;letter-spacing:0}.site-header nav{gap:9px}.help-button{display:none}.support-button{min-width:44px;width:44px;padding:0;justify-content:center}.support-button>span:last-child{display:none}.language-picker{gap:3px}.language-picker select{font-size:11px;max-width:82px;padding:0}.language-picker svg{width:14px;height:14px}.workspace-heading h1{font-size:25px}.notebook-caption{font-size:9px;gap:8px}.notebook-caption>span:last-child{font-size:9px;letter-spacing:0}.saved-label{display:none}.below-calculator>span{max-width:55%}.below-calculator .text-button{font-size:9px}.site-footer>div{column-gap:10px;row-gap:0}.site-footer>span{line-height:1.8}.site-footer .text-button{font-size:9px}.help-list>div{grid-template-columns:105px minmax(0,1fr)}.keypad-footer{font-size:9px}.keypad-footer .text-button{font-size:9px}.tabs{gap:17px}.tabs button{font-size:11px}.keypad-options{flex-wrap:nowrap}}
/* Owner-supplied payment codes are displayed without recoloring or cropping. */
#donation-dialog.has-payment-methods .donation-art{width:56px;height:56px;margin:6px auto 12px}#donation-dialog.has-payment-methods .donation-art svg{width:29px;height:29px}#donation-dialog.has-payment-methods .coffee-heart{width:22px;height:22px;line-height:22px;font-size:19px;top:0;right:-2px}#donation-dialog.has-payment-methods .dialog-lead{font-size:12px;margin-bottom:16px}#donation-dialog.has-payment-methods .fine-print{margin-top:7px}.payment-tabs{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:4px;background:var(--accent-soft);padding:4px;border:1px solid var(--line);border-radius:11px;margin:16px 0}.payment-tab{min-height:44px;background:var(--white-space);border-radius:8px;color:var(--ink-2);font-size:12px;padding:8px 10px}.payment-tab[aria-selected=true]{background:var(--canvas);color:var(--accent);box-shadow:var(--shadow);font-weight:600}.payment-tab:hover{color:var(--accent);background:var(--surface)}.payment-panel{text-align:center}.payment-qr-frame{display:flex;align-items:center;justify-content:center;width:244px;max-width:100%;min-height:240px;margin:0 auto;padding:12px;background:var(--canvas);border:1px solid var(--line);border-radius:12px}.payment-qr{display:block;width:218px;max-width:100%;height:auto;border-radius:0;image-rendering:pixelated;user-select:auto}.payment-qr-error{font-size:12px;color:var(--ink-3);line-height:1.8}.payment-panel [hidden]{display:none}.payment-instructions{font-size:11px;line-height:1.9;color:var(--ink-3);margin:12px auto 14px;max-width:300px}.payment-actions{display:flex;flex-wrap:wrap;gap:8px;justify-content:center}.payment-save,.payment-open{display:inline-flex;align-items:center;justify-content:center;min-height:44px;padding:10px 16px;border-radius:10px;text-decoration:none;font-size:12px;white-space:nowrap;flex:1 1 120px}.payment-save{background:var(--accent-soft);color:var(--accent);border:1px solid var(--line)}.payment-save:hover{background:var(--key-hover)}.payment-open{background:var(--accent);color:var(--on-accent);border:1px solid var(--accent)}.payment-open:hover{background:var(--accent-hover)}
@media(max-width:360px){#donation-dialog.has-payment-methods{padding:17px}.payment-tab{padding:8px 4px;font-size:11px}.payment-save,.payment-open{font-size:11px;padding:10px 12px}.payment-instructions{font-size:10px}}
/* finesse · component=math-input · register=product · tokens=existing */
math-field.expression-input{display:block;width:100%;min-height:50px;padding:0;border:0;border-radius:0;background:var(--white-space);color:var(--ink);font-family:var(--font-math);font-size:24px;line-height:1.5;letter-spacing:normal;direction:ltr;--caret-color:var(--accent);--selection-background-color:var(--accent-soft);--selection-color:var(--ink);--contains-highlight-background-color:var(--accent-soft);--placeholder-color:var(--ink-3);--smart-fence-color:var(--ink-3);--horizontal-padding:0px;--vertical-padding:5px}math-field.expression-input::part(container){padding:6px 0;min-height:50px}math-field.expression-input::part(content){padding:0}math-field.expression-input::part(virtual-keyboard-toggle),math-field.expression-input::part(menu-toggle){display:none}math-field.expression-input:focus-visible{outline:2px solid var(--accent);outline-offset:3px}math-field.expression-input[aria-invalid=true]{color:var(--error)}math-field.expression-input[disabled]{opacity:.5;cursor:not-allowed}.expression-row{min-height:102px}.math-loading{min-height:102px;padding:26px 24px;color:var(--ink-3);font-size:12px;display:flex;align-items:center}.math-cursor-controls{display:flex;align-items:center;gap:2px;direction:ltr}.math-cursor-controls .icon-button{font-size:17px;width:32px;min-height:36px;min-width:32px}.keypad-footer{row-gap:0}.fraction-key{display:inline-flex;flex-direction:column;align-items:stretch;justify-content:center;min-width:15px;font-family:var(--font-math);font-size:16px;line-height:1.05;text-align:center}.fraction-key>span:first-child{border-bottom:1px solid currentColor;padding:0 4px 2px}.fraction-key>span:last-child{padding:2px 4px 0}.expression-row.is-hover{background:var(--surface)}
@media(hover:hover){math-field.expression-input:hover{background:var(--surface)}}
@media(max-width:600px){math-field.expression-input{font-size:22px;min-height:52px}.expression-row{min-height:102px}.math-cursor-controls{order:3;justify-content:center;width:100%;padding-bottom:4px}.math-cursor-controls .icon-button{width:44px;min-width:44px;min-height:44px}.keypad-footer{justify-content:space-between}.notebook-caption{align-items:center}.notebook-caption>span:last-child{max-width:72%;line-height:1.7}}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}*,*::before,*::after{animation-duration:.01ms!important;animation-iteration-count:1!important;transition-duration:.01ms!important}.toast{transform:translate(-50%,0)}}