/* The teaching layer: worked constructions on the research site's white paper. */
.math-overview{max-width:840px;border-top:1px solid var(--line);margin-top:28px;padding-top:23px}.math-overview h2{font:11px/1.7 var(--mono);text-transform:uppercase;letter-spacing:1px;color:#4d7a91;margin-bottom:13px}.math-overview p{font-size:17px;line-height:1.75}.math-overview strong{font-weight:600}.math-overview .links{margin-top:17px}
.math-teaching-hero .lede{max-width:840px}.hero-proof-heading{margin-top:36px;max-width:860px}.hero-proof-heading h2{font-size:30px;margin:8px 0 13px}.hero-proof-heading>p:last-child{max-width:790px}.hero-proof-composition{display:grid;grid-template-columns:minmax(0,.86fr) minmax(0,1.14fr);gap:25px;margin-top:25px;align-items:start}.pigeonhole-plate{margin:0;min-width:0;background:#f8fbfd;border:1px solid #dce7ef}.pigeonhole-plate img{display:block;width:100%;height:auto}.pigeonhole-plate figcaption{padding:14px 18px;border-top:1px solid #dce7ef;font:12px/1.7 var(--sans);color:#586f81}.hero-proof-scope{font:14px/1.8 var(--sans);color:#526979;border-left:2px solid #7b9caf;padding:4px 0 4px 18px;margin-top:24px}.hero-proof-details{border-top:1px solid var(--line);border-bottom:1px solid var(--line);margin-top:22px}.hero-proof-details>summary,.math-formal>summary{font:14px/1.7 var(--sans);color:var(--accent);cursor:pointer;padding:17px 0}.hero-proof-details>div{padding:8px 0 26px}.hero-proof-details h3{font-size:23px;margin:28px 0 12px}.hero-proof-details .math-equation{white-space:normal}.math-introduction h2{margin-bottom:15px}
.math-term{text-decoration-style:dotted;text-underline-offset:4px}.math-term:hover{text-decoration-style:solid}.lesson-title{font-size:26px!important;margin:10px 0 24px!important;max-width:730px}.lesson-step{display:grid;grid-template-columns:26px minmax(0,1fr);gap:17px;margin:23px 0}.lesson-step-number{font:12px/1.6 var(--mono);color:#5c879b;border-top:1px solid #a2bdcb;padding-top:7px}.lesson-step h3{font-size:21px;margin:0 0 10px}.lesson-step p{max-width:740px}.lesson-calculation{font:19px/1.8 Cambria,Georgia,serif;color:#315d82;background:#f8fbfd;border-left:2px solid #96b2c3;padding:14px 18px;margin:20px 0 4px;overflow-wrap:anywhere}.lesson-vocabulary{font:13px/1.9 var(--sans);margin-top:24px;color:#607382}.lesson-vocabulary>span{display:block;font:10px/1.8 var(--mono);text-transform:uppercase;letter-spacing:1px;margin-bottom:5px}.math-blueprint{margin:30px 0 24px;border:1px solid #dce7ef;background:#f8fbfd}.math-plate-heading{display:flex;align-items:baseline;gap:18px;justify-content:space-between;border-bottom:1px solid #dce7ef;padding:14px 20px}.math-plate-heading span{font:10px/1.7 var(--mono);color:#4d7a91;text-transform:uppercase;letter-spacing:.5px}.math-plate-heading strong{font:14px/1.5 var(--serif);color:#315d82}.math-plate-scroll{overflow-x:auto;min-width:0;overscroll-behavior-x:contain}.math-plate-scroll img{width:100%;display:block;height:auto}.math-plate-scroll:focus-visible{outline:2px solid var(--teal);outline-offset:-3px}.math-blueprint figcaption{padding:15px 20px;border-top:1px solid #dce7ef;font:12px/1.8 var(--sans);color:#526c7e}.math-blueprint figcaption a{white-space:nowrap;margin-left:8px}.math-formal{border-top:1px solid var(--line);border-bottom:1px solid var(--line)}.math-formal[open]>summary{border-bottom:1px solid var(--line)}.math-formal-content{padding:24px 0}.math-formal-content>.math-status{margin-bottom:20px}.lesson-next{font:13px/1.7 var(--sans);margin-top:24px}.math-definitions>h2{margin-top:10px}.definition-group{margin-top:32px}.definition-group>h3{font-size:21px;border-bottom:1px solid var(--line);padding-bottom:13px}.definition-group dl{display:grid;grid-template-columns:1fr 1fr;gap:0 35px;margin:0}.definition-group dl>div{padding:18px 0;border-bottom:1px solid var(--line);scroll-margin-top:35px}.definition-group dt{font:600 14px/1.7 var(--sans);color:#315d82}.definition-group dd{font:14px/1.8 var(--sans);margin:8px 0 0;color:#52616d}.definition-group dl>div:target{background:#eff6f8;outline:7px solid #eff6f8}.math-entry-body{min-width:0}

/* Adapted Halcyon centerline handwriting; accessible HTML remains authoritative. */
#pigeonhole-board{min-width:0;--pen:#315d82}#pigeonhole-board .math-content{padding:0}.ink-tools{display:flex;flex-wrap:wrap;gap:7px;align-items:center;padding:13px;background:#f4f8fb;border:1px solid #dce7ef}.ink-tools button{font:11px/1.5 var(--sans);padding:7px 10px;min-height:36px;color:#315d82;border-color:#b8cbd7;background:white}.ink-tools button[aria-pressed=true]{background:#315d82;color:white}.ink-status{flex-basis:100%;font:10px/1.7 var(--mono);color:#55788e}.ink-status::before{content:'';display:inline-block;width:5px;height:5px;border-radius:50%;background:var(--teal);margin-right:8px}.ink-instruction{font:11px/1.7 var(--sans);color:#5d7689;padding:12px 14px;border:1px solid #dce7ef;border-top:0;margin:0}.eq{padding:19px 18px;border:1px solid #dce7ef;border-top:0;position:relative;background:#f8fbfd;background-image:radial-gradient(#c4d5e44a .65px,transparent .8px);background-size:18px 18px}.eq-label{font:10px/1.7 var(--mono);letter-spacing:.3px;color:#476f88}.eq-line{font:23px/1.6 Cambria,Georgia,serif;margin:14px 0;color:#315d82}.eq-note{font:12px/1.8 var(--sans);color:#526a7c}.ink-surface{color:var(--pen);margin:1px -3px;min-width:0}.ink-surface svg{display:block;width:100%;overflow:visible}.ink-stroke{fill:none;stroke:currentColor;stroke-linecap:round;stroke-linejoin:round}.ink-tip{fill:#287c72}.ink-ready:not(.ink-typeset) .eq-line{position:absolute;width:1px;height:1px;overflow:hidden;clip-path:inset(50%);white-space:nowrap}.ink-typeset .ink-surface{display:none}.ink-typeset .eq-line{overflow-wrap:anywhere}.ink-footer{display:flex;flex-wrap:wrap;gap:5px 12px;justify-content:space-between;font:9px/1.7 var(--mono);color:#607e91;padding-top:12px}
@media(max-width:850px){.hero-proof-composition{grid-template-columns:1fr}.pigeonhole-plate{max-width:680px;margin:auto}.definition-group dl{gap:0 25px}.math-entry-body{margin-left:0}.math-plate-heading{display:block}.math-plate-heading strong{display:block;margin-top:5px}.math-blueprint .math-plate-scroll img{min-width:850px}.pigeonhole-plate .math-plate-scroll img{min-width:540px}.math-blueprint figcaption::after,.pigeonhole-plate figcaption::after{content:' On a small screen, scroll the drawing sideways to inspect its details.'}.hero-proof-heading h2{font-size:27px}#pigeonhole-board{max-width:680px;width:100%;margin:auto}}
@media(max-width:550px){.definition-group dl{grid-template-columns:1fr}.lesson-title{font-size:23px!important}.lesson-step{gap:10px;grid-template-columns:20px minmax(0,1fr)}.lesson-step h3{font-size:20px}.lesson-calculation{font-size:17px;padding:12px}.math-plate-heading{padding:12px 14px}.math-blueprint figcaption{padding:13px 14px}.hero-proof-composition{gap:24px}.eq{padding:17px 14px}.hero-proof-heading>p:last-child{font-size:16px}}
.pigeonhole-plate{width:100%}
@media(prefers-reduced-motion:reduce){html{scroll-behavior:auto}}
@media print{.ink-tools,.ink-instruction,.ink-footer{display:none!important}.ink-surface{display:none!important}#pigeonhole-board .eq-line{position:static!important;width:auto!important;height:auto!important;clip-path:none!important;white-space:normal!important}.hero-proof-composition{display:block}.pigeonhole-plate{max-width:470px;margin:20px auto}.math-blueprint .math-plate-scroll img,.pigeonhole-plate .math-plate-scroll img{min-width:0}.math-plate-scroll{overflow:visible}.math-blueprint figcaption::after,.pigeonhole-plate figcaption::after{content:none}.math-blueprint{break-inside:avoid}.definition-group dl{display:block}}

/* Project connections stay visible outside the expandable formal notes. */
.math-project-connections{margin-top:28px;padding:24px 0 4px;border-top:1px solid var(--line)}.math-project-connections>h3{font-size:24px;margin:8px 0 20px}.math-project-list{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));gap:24px 32px}.math-project-list article{border-top:1px solid #dce7ef;padding-top:16px}.math-project-list h4{font-size:20px;font-weight:400;line-height:1.4;margin:8px 0 10px}.math-project-list .math-project-kind{font:10px/1.7 var(--mono);letter-spacing:.3px;color:#58798c}.math-project-list article>p:last-child{font:15px/1.75 var(--serif);color:#435c6b}.math-project-list article:only-child{grid-column:1/-1}@media(max-width:650px){.math-project-list{grid-template-columns:1fr;gap:20px}}