/* ============================================================
   EUCLIDE.CSS — solo ciò che è proprio della sezione «Elementi di Euclide».
   Tutto il resto viene da lezioni/comune/lezione.css (che a sua volta
   poggia su css/math-base.css): stessi colori, stessi riquadri.
   ============================================================ */

/* rimando a definizioni, postulati, nozioni comuni, proposizioni */
.eu-rif { display: inline-block; font-size: .78em; font-weight: 700; line-height: 1.35; padding: 0 .5em; margin: 0 .1em; border-radius: 999px;
    color: var(--brand); background: var(--brand-light); border: 1px solid color-mix(in srgb, var(--brand) 25%, transparent);
    text-decoration: none; white-space: nowrap; vertical-align: .08em; }
a.eu-rif:hover { background: var(--brand); color: var(--card); }
a.eu-rif:focus-visible { outline: 3px solid var(--ring); outline-offset: 1px; }

/* la scheda dopo la lezione */
.lz-scheda { margin-top: 2rem; padding: 1.3rem 1.4rem; max-width: 820px; }
.lz-scheda h2 { margin: 0 0 .8rem; color: var(--brand-deep); }
.lz-scheda h3 { margin: 0 0 .35rem; font-size: .8rem; text-transform: uppercase; letter-spacing: .06em; color: var(--ink-2); }
.lz-scheda > div + div { margin-top: 1rem; padding-top: 1rem; border-top: 1px solid var(--border-gray); }
.eu-parole blockquote { margin: 0; padding: .6rem .9rem; border-left: 4px solid var(--brand); background: var(--gray-light); border-radius: 0 8px 8px 0;
    font-family: Georgia, "Times New Roman", serif; font-style: italic; font-size: 1.02rem; line-height: 1.55; color: var(--ink); }
.eu-chiusa { margin: .45rem 0 0; font-size: .88rem; color: var(--ink-2); }
.eu-rifs { margin: 0; display: flex; flex-wrap: wrap; gap: 6px; }
.eu-rifs .eu-rif { font-size: .85rem; padding: .15em .7em; }
.eu-nessuna { font-size: .92rem; color: var(--ink-2); }
.eu-storia p { margin: .3em 0 .5em; }
.eu-links { display: grid; grid-template-columns: repeat(auto-fit, minmax(230px, 1fr)); gap: 8px; }
.eu-link { display: flex; flex-direction: column; gap: 2px; padding: 10px 12px; border: 1px solid var(--border-gray); border-radius: var(--radius-sm, 10px);
    background: var(--card); color: var(--ink); text-decoration: none; font-weight: 600; transition: border-color .15s, transform .15s; }
.eu-link:hover { border-color: var(--brand); transform: translateY(-2px); }
.eu-link-tag { font-size: .7rem; font-weight: 700; text-transform: uppercase; letter-spacing: .05em; color: var(--brand); }
.eu-link.est .eu-link-tag { color: var(--area-corsi); }

/* tabelline dentro i passi (definizioni, postulati) */
.eu-tab { width: 100%; border-collapse: collapse; font-size: .9rem; margin: .4em 0 .6em; }
.eu-tab th, .eu-tab td { text-align: left; padding: 5px 8px; border-bottom: 1px solid var(--border-gray); vertical-align: top; }
.eu-tab th { font-size: .75rem; text-transform: uppercase; letter-spacing: .04em; color: var(--ink-2); }

/* ---- indice della sezione ---- */
.eu-mappa { margin: 2.2rem 0 1rem; padding: 1.2rem 1.3rem; }
.eu-mappa h2 { margin: 0 0 .3rem; color: var(--brand-deep); }
.eu-mappa > p { margin: 0 0 .8rem; color: var(--ink-2); }
.eu-mappa-barra { display: flex; flex-wrap: wrap; gap: 8px; align-items: center; margin-bottom: .6rem; }
.eu-mappa-barra select { font: inherit; padding: 6px 10px; border-radius: 8px; border: 1px solid var(--border-gray); background: var(--card); color: var(--ink); max-width: 100%; }
.eu-mappa-info { font-size: .9rem; color: var(--ink-2); margin: .2rem 0 .6rem; min-height: 1.4em; }
.eu-mappa-scorri { overflow-x: auto; -webkit-overflow-scrolling: touch; border: 1px solid var(--border-gray); border-radius: 10px; background: var(--card); }
.eu-mappa svg { display: block; }
.eu-nodo rect { fill: var(--card); stroke: var(--border-gray); stroke-width: 1.2; transition: fill .15s, stroke .15s; }
.eu-nodo text { font: 700 11px/1 system-ui, sans-serif; fill: var(--ink-2); text-anchor: middle; dominant-baseline: central; pointer-events: none; }
.eu-nodo { cursor: pointer; }
.eu-nodo.v5 rect { stroke-dasharray: 3 2; }
.eu-nodo.su rect { fill: var(--brand-light); stroke: var(--brand); }
.eu-nodo.su text { fill: var(--brand-deep); }
.eu-nodo.giu rect { fill: color-mix(in srgb, var(--area-corsi) 12%, var(--card)); stroke: var(--area-corsi); }
.eu-nodo.giu text { fill: var(--area-corsi); }
.eu-nodo.scelto rect { fill: var(--brand); stroke: var(--brand); }
.eu-nodo.scelto text { fill: var(--card); }
.eu-arco { fill: none; stroke: var(--border-gray); stroke-width: 1; opacity: .35; }
.eu-arco.su { stroke: var(--brand); opacity: .9; stroke-width: 1.4; }
.eu-arco.giu { stroke: var(--area-corsi); opacity: .8; stroke-width: 1.2; }
.eu-legenda { display: flex; flex-wrap: wrap; gap: 14px; font-size: .8rem; color: var(--ink-2); margin-top: .6rem; }
.eu-legenda span::before { content: ""; display: inline-block; width: 12px; height: 12px; border-radius: 3px; margin-right: 5px; vertical-align: -2px; border: 1.5px solid var(--border-gray); }
.eu-legenda .l-su::before { background: var(--brand-light); border-color: var(--brand); }
.eu-legenda .l-giu::before { background: color-mix(in srgb, var(--area-corsi) 12%, var(--card)); border-color: var(--area-corsi); }
.eu-legenda .l-v5::before { border-style: dashed; }
.eu-capdesc { margin: -.2rem 0 .8rem; color: var(--ink-2); font-size: .95rem; max-width: 75ch; }