/* Brand lettering stays decorative; lesson mathematics uses clear, upright digits. */
.cover-studio-sign{display:flex;align-items:center;gap:17px;flex-wrap:wrap;margin:-6px 0 25px;color:#89679f}
.cover-studio-sign>span{font:italic 21px/1.5 Georgia,serif;letter-spacing:.015em}
.cover-studio-sign>b{font-size:12px;font-weight:500;letter-spacing:.19em;border-left:1px solid #d7c5e4;padding-left:17px}
.cover-map-button{max-width:410px;width:100%;display:flex;align-items:center;gap:12px;text-align:left;border:1px solid #e0d2e9;background:#ffffff88;border-radius:9px;min-height:65px;padding:12px 16px;margin-top:14px;color:#826095}
.cover-map-button>span:first-child{font-size:26px;font-weight:300;color:#b69bc8}.cover-map-button>span:nth-child(2){flex:1;font-size:12px;letter-spacing:.05em}.cover-map-button small{display:block;font-size:9px;letter-spacing:0;color:#a38bb2;margin-top:3px}.cover-map-button>b{font-size:18px;font-weight:400}
.quadratic-formula-image{display:block;width:100%;height:auto;max-width:420px;object-fit:contain;margin:8px auto 12px;flex:none;aspect-ratio:420/145}
.hero-art.hero-formula{height:auto;min-height:0;min-width:0;align-self:stretch;overflow:visible}
.hero-formula .quadratic-formula-image,.cover-formula .quadratic-formula-image{width:100%;height:auto;max-width:420px;min-height:0;flex-shrink:0;overflow:visible}
.hero:has(.hero-formula){overflow:visible}
.hero-formula h3,.hero-formula .hero-equation{white-space:normal;overflow-wrap:normal}
.cover-formula{overflow:visible;padding:18px 0 5px}
.notes-entry .math,.notes-reference .study-example .math,.notes-reference .study-check p,.notes-reference .study-decisions td,.study-concept,.formula-expression,.study-visual svg text,.formula-box .math{font-family:ui-monospace,"SFMono-Regular",Consolas,"Liberation Mono","Noto Sans TC",monospace;font-variant-numeric:lining-nums tabular-nums slashed-zero;font-feature-settings:"zero" 1;letter-spacing:0}
.notes-entry .math{font-size:16px;line-height:1.9}.notes-entry>.math{display:block;overflow-x:auto;white-space:nowrap;padding-bottom:5px;max-width:100%}
.study-visual-gallery:empty{display:none}.study-visual-gallery{display:grid;grid-template-columns:repeat(auto-fit,minmax(min(100%,270px),1fr));gap:14px;margin:14px 0 21px;min-width:0}
.study-visual{margin:0;border:1px solid #e7dbef;border-radius:12px;background:linear-gradient(145deg,#fbf9fd,#f7f2fb);padding:18px 16px;min-width:0;color:#80608f}
.study-visual h5{font-size:13px;line-height:1.7;margin:0 0 10px;color:#755087;letter-spacing:.015em}
.study-visual svg{display:block;width:100%;height:auto;max-width:420px;margin:0 auto;stroke:#9875ae;stroke-width:1.8;fill:none;stroke-linejoin:round;stroke-linecap:round}
.study-visual svg .filled{fill:#e9dcf461}.study-visual svg .aux{stroke:#bca3cb;stroke-dasharray:5 5;stroke-width:1.4}.study-visual svg .axis{stroke:#bca9c9;stroke-width:1.3}.study-visual svg .accent{stroke:#73508d;stroke-width:2.5}.study-visual svg .highlight{stroke:#bc877a;stroke-width:4}.study-visual svg .point{fill:#73508d;stroke:none}.study-visual svg text{stroke:none;fill:#77528c;font-size:15px;line-height:1.3}
.study-visual figcaption{font-size:12px;line-height:1.9;color:#8c719c;margin-top:10px;overflow-wrap:anywhere}.study-visual figcaption small{display:block;font-size:10px;margin-top:6px;color:#b19bbd}
.studio-dialog{width:min(1000px,calc(100vw - 28px));max-width:1000px;max-height:calc(100dvh - 28px);padding:28px;border:1px solid #dbc9e8;border-radius:18px;background:#fbf9fd;color:#745385;overflow-y:auto;overscroll-behavior:contain;box-shadow:0 24px 100px #442a5a44}
.studio-dialog::backdrop{background:#32203d88;backdrop-filter:blur(4px)}
.studio-dialog>div{display:block}.studio-dialog>.studio-dialog-head{display:flex;justify-content:space-between;align-items:flex-start;gap:15px}.studio-dialog-head>div{min-width:0}.studio-dialog h2{font-size:26px;line-height:1.6;margin:7px 0 9px;letter-spacing:.03em;color:#654575}.studio-dialog-head p{font-size:12px;line-height:1.9;color:#9d84ae;margin:0 0 20px}.studio-dialog-head>.sidebar-toggle{flex:none}.studio-dialog>.dialog-footer{display:flex}
.formula-dialog>.formula-results{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:10px}
.formula-entry{display:flex;align-items:center;justify-content:space-between;gap:16px;text-align:left;min-height:90px;padding:17px 19px;border:1px solid #e3d6ec;background:white;border-radius:11px;color:#806091;min-width:0;transition:border-color .15s,background .15s}
.formula-entry:hover{background:#f5eefb;border-color:#baa0cd}.formula-entry small{display:block;font-size:10px;color:#ad95bd;margin-bottom:5px}.formula-entry b{font-size:15px;font-weight:600;line-height:1.6}.formula-entry>span:last-child{font-size:21px;color:#b39bc1;flex:none}
.formula-detail-dialog{width:min(760px,calc(100vw - 28px));max-width:760px}.formula-detail-meta{font-size:11px;color:#aa91b9;margin-top:15px!important;margin-bottom:4px!important}.formula-detail-equation{font:15px/1.8 ui-monospace,Consolas,monospace;text-align:center;color:#9878ab;margin-top:22px!important}.formula-detail-dialog .quadratic-formula-image{margin:20px auto 25px;max-width:470px}
.formula-detail-expression{white-space:nowrap;overflow-wrap:normal;word-break:normal;overflow-x:auto;max-width:100%;font-size:clamp(17px,2.6vw,23px);line-height:2;padding:20px;margin:12px 0;scrollbar-width:thin;scrollbar-color:#ceb6df #f3ecf8}
.formula-scroll-hint{font-size:10px!important;color:#b198c0!important;margin:8px 0 20px!important}.formula-conditions{background:white;border:1px solid #e8deef;border-radius:10px;padding:18px 20px;margin-top:20px}.formula-conditions h3{font-size:13px;margin:0 0 7px}.formula-conditions p{font-size:13px;line-height:2;color:#9477a4;margin:0}
.studio-dialog>.tree-root{display:flex;flex-direction:column;align-items:center;gap:4px;text-align:center;border:1px solid #d8c3e6;border-radius:13px;max-width:420px;margin:8px auto 25px;padding:20px;background:linear-gradient(110deg,#eee2f7,#faf5fd)}
.tree-root b{font:30px/1.5 Georgia,serif;letter-spacing:.08em}.tree-root span{font-size:13px;letter-spacing:.13em}.tree-root small{font-size:10px;color:#a187b2;margin-top:5px}.studio-dialog>.tree-tools{display:flex;gap:8px;justify-content:flex-end;margin-bottom:15px}.tree-tools .button{font-size:11px;padding:8px 13px}
.tree-grade{margin-bottom:20px;border:1px solid #e1d1ec;background:white;border-radius:12px;overflow:hidden}.tree-grade>summary{display:flex;align-items:center;gap:13px;cursor:pointer;list-style:none;padding:15px 20px;background:#eee3f7;font-size:16px}.tree-grade>summary::after,.tree-term>summary::after{content:'+';margin-left:auto;font-size:20px;font-weight:400}.tree-grade[open]>summary::after,.tree-term[open]>summary::after{content:'−'}.tree-grade>summary>span{font:12px ui-monospace,monospace;color:#ac8ebf}.tree-grade>summary small{font-size:11px;color:#a185b2;font-weight:400}.tree-terms{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:20px;padding:20px}.tree-term{min-width:0}.tree-term>summary{display:flex;align-items:center;gap:8px;cursor:pointer;font-size:13px;font-weight:600;border-bottom:1px solid #e6d8ee;padding:0 0 10px;color:#9472a9;list-style:none}.tree-term>ol{margin:16px 0 0 10px;padding:0 0 0 20px;border-left:1px solid #dfcde9;list-style:none}.tree-unit{position:relative;margin-bottom:20px}.tree-unit::before{content:'';position:absolute;left:-21px;top:14px;width:13px;border-top:1px solid #dfcde9}.tree-unit>div{display:flex;gap:8px;align-items:baseline}.tree-unit>div>span{font:10px ui-monospace,monospace;color:#a086b1}.tree-unit h3{font-size:13px;line-height:1.9;margin:0 0 7px;color:#7c588e}.tree-unit ul{list-style:none;margin:0;padding:0 0 0 5px}.tree-unit button{width:100%;display:flex;align-items:baseline;gap:7px;text-align:left;min-height:41px;font-size:11px;line-height:1.8;background:none;padding:7px 8px;border-radius:6px;color:#9d84ad}.tree-unit button:hover{background:#f4edf9;color:#73508d}.tree-unit button>span{font-size:9px;color:#b9a5c5;flex:none}.tree-unit button>b{margin-left:auto;font-weight:400;flex:none}
.mistake-semester{margin-bottom:25px}.mistake-semester>h3{font-size:13px;color:#a185b3;letter-spacing:.08em;padding:14px 0 9px;border-bottom:1px solid #e6d9ed}.mistake-unit-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:14px}.mistake-unit{border:1px solid #e4d7ed;border-radius:11px;padding:20px;background:white;min-width:0}.mistake-unit h4{display:flex;gap:12px;justify-content:space-between;font-size:15px;margin:8px 0 15px;line-height:1.7}.mistake-unit h4>b{font-size:12px;white-space:nowrap;color:#aa86bc}.mistake-unit ul{list-style:none;margin:0 0 18px;padding:0;font-size:11px;color:#a38bb2}.mistake-unit li{display:flex;gap:10px;justify-content:space-between;margin:7px 0}.mistake-unit li span{white-space:nowrap;color:#b4a0bf}.mistake-unit .button{width:100%;font-size:12px;background:#8a68a0}.mistakes-dialog #review-all{font-size:12px;margin-top:5px}
.suggestion-card>.journal-banner{display:flex;flex-direction:column;align-items:flex-start;gap:10px;margin:25px 0 0;padding:19px 16px;border-radius:9px}.suggestion-card>.journal-banner p{margin:8px 0 0;font-size:11px}.suggestion-card>.journal-banner .eyebrow{font-size:9px}.suggestion-card>.journal-banner .cloud-state{font-size:10px;margin-top:0;max-width:100%;white-space:normal}
@media(max-width:1000px){.hero{grid-template-columns:minmax(0,1fr) minmax(245px,.8fr);gap:22px}.hero-art.hero-formula{padding:22px 15px}.hero-formula h3{font-size:14px}.hero .hero-formula .hero-equation{font-size:11px}.hero .hero-formula .hero-formula-tip{font-size:10px}.tree-terms{gap:16px;padding:16px}}
@media(max-width:760px){.cover-studio-sign{margin-top:-5px;gap:11px}.cover-studio-sign>span{font-size:20px}.cover-studio-sign>b{font-size:10px;padding-left:11px;letter-spacing:.12em}.cover-map-button{max-width:none}.hero{grid-template-columns:minmax(0,1fr)}.hero-art.hero-formula{display:flex;max-width:none;width:100%;padding:21px}.hero-formula .quadratic-formula-image{max-width:345px}.hero-formula h3{font-size:15px}.hero .hero-formula .hero-equation{font-size:12px}.hero-formula .formula-open{max-width:390px}.studio-dialog{padding:21px 17px}.studio-dialog h2{font-size:21px}.formula-dialog>.formula-results{grid-template-columns:1fr}.formula-entry{min-height:80px;padding:14px 16px}.formula-detail-expression{padding:17px 14px}.tree-terms{grid-template-columns:1fr;gap:20px}.tree-grade>summary{padding:14px}.tree-grade>summary small{font-size:10px}.tree-unit button{font-size:12px;min-height:44px}.tree-unit h3{font-size:14px}.tree-unit ul{padding-left:0}.tree-term>summary{font-size:14px}.study-visual-gallery{grid-template-columns:minmax(0,1fr)}.mistake-unit-grid{grid-template-columns:1fr}.study-visual{padding:16px}.study-visual figcaption{font-size:12px}.notes-entry h4{gap:9px}.notes-entry button{flex:none}.studio-dialog .dialog-footer .button{font-size:12px}}
@media(max-width:380px){.cover-studio-sign{gap:8px}.cover-studio-sign>span{font-size:18px}.cover-studio-sign>b{font-size:9px;padding-left:8px}.cover-map-button{padding:12px}.cover-map-button small{font-size:8px}.hero-art.hero-formula{padding:18px 13px}.hero-formula .quadratic-formula-image{min-width:0}}
@media(prefers-reduced-motion:reduce){.formula-entry{transition:none}}
@media print{.study-visual{break-inside:avoid}.studio-dialog{box-shadow:none}}

.review-complete{display:flex;align-items:center;gap:14px;justify-content:space-between;flex-wrap:wrap;padding:16px 0;color:#8a679b;font-size:12px}.review-complete .button{font-size:11px}
/* Larger formula reading surfaces on desktop and landscape devices. */
@media (min-width:1024px), (min-width:600px) and (orientation:landscape){
 .formula-dialog{width:min(1360px,calc(100vw - 40px));max-width:1360px;max-height:calc(100dvh - 24px);padding:clamp(22px,2.5vw,38px)}
 .formula-detail-dialog{width:min(1160px,calc(100vw - 40px));max-width:1160px;max-height:calc(100dvh - 24px);padding:clamp(22px,2.5vw,38px)}
 .formula-detail-expression{font-size:clamp(22px,2.5vw,32px);padding:24px;line-height:2}
 .formula-detail-dialog .quadratic-formula-image{width:min(100%,640px);max-width:640px;height:auto}
 .formula-detail-dialog .formula-conditions p{font-size:15px;line-height:2}
 .formula-dialog .formula-search-tools{grid-template-columns:minmax(0,1fr) 180px}
 .formula-dialog>.formula-results{grid-template-columns:repeat(2,minmax(0,1fr))}
}
@media (min-width:1250px){.formula-dialog>.formula-results{grid-template-columns:repeat(3,minmax(0,1fr))}}
@media (min-width:600px) and (orientation:landscape) and (max-height:600px){
 .formula-dialog,.formula-detail-dialog{width:calc(100vw - 20px);max-height:calc(100dvh - 12px);padding:18px 24px}
 .formula-dialog-head p{margin-bottom:10px}.formula-categories{margin:10px 0}
 .formula-detail-dialog .studio-dialog-head{gap:10px}.formula-detail-dialog .dialog-footer{margin-top:15px;padding-top:12px}
}