.wrap[data-astro-cid-2vg3rhsp]{max-width:var(--maxw-read);padding-inline:var(--s-4);margin-inline:auto}.eb-cover[data-astro-cid-2vg3rhsp]{align-items:center;gap:var(--s-6);max-width:var(--maxw);padding-block:var(--s-7) var(--s-6);grid-template-columns:minmax(0,1.1fr) minmax(240px,.7fr);display:grid}.eb-cover__title[data-astro-cid-2vg3rhsp]{font-size:var(--step-6);margin-block:var(--s-3);line-height:1.08}.eb-cover__desc[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-size:var(--step-1);max-width:56ch;line-height:1.55}.eb-cover__meta[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-size:var(--step--1);align-items:center;gap:var(--s-3);margin-top:var(--s-3);flex-wrap:wrap;display:flex}.eb-cover__level[data-astro-cid-2vg3rhsp]{text-transform:capitalize;border-radius:100px;padding:3px 12px;font-weight:600}.level--beginner[data-astro-cid-2vg3rhsp]{background:var(--formula-tint);color:var(--formula-text)}.level--intermediate[data-astro-cid-2vg3rhsp]{background:var(--amber-tint);color:var(--amber-text)}.level--advanced[data-astro-cid-2vg3rhsp]{background:var(--paper-2);color:var(--ink-soft)}.eb-cover__actions[data-astro-cid-2vg3rhsp]{gap:var(--s-3);margin-top:var(--s-5);margin-bottom:var(--s-3);flex-wrap:wrap;display:flex}.eb-cover__gate-note[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-size:var(--step--1);margin-bottom:var(--s-4)}.eb-cover__gate-note[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp]{color:var(--formula-text)}.eb-cover__art[data-astro-cid-2vg3rhsp]{width:100%;max-width:320px;margin-inline:auto}@media (width<=820px){.eb-cover[data-astro-cid-2vg3rhsp]{grid-template-columns:1fr}.eb-cover__art[data-astro-cid-2vg3rhsp]{order:-1;max-width:220px}}.eb-toc[data-astro-cid-2vg3rhsp]{background:var(--paper-2);border:1px solid var(--grid);border-radius:var(--radius-lg);margin-bottom:var(--s-6);padding:var(--s-5)}.eb-toc__head[data-astro-cid-2vg3rhsp] h2[data-astro-cid-2vg3rhsp]{font-size:var(--step-3);margin-top:var(--s-2)}.eb-toc__list[data-astro-cid-2vg3rhsp]{columns:2;column-gap:var(--s-5);margin-top:var(--s-4);padding-left:0;list-style:none}.eb-toc__list[data-astro-cid-2vg3rhsp] li[data-astro-cid-2vg3rhsp]{break-inside:avoid;margin-block:var(--s-1)}.eb-toc__list[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp]{color:var(--formula-text);text-decoration:none}.eb-toc__list[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp]:hover{text-decoration:underline}@media (width<=640px){.eb-toc__list[data-astro-cid-2vg3rhsp]{columns:1}}.eb-article[data-astro-cid-2vg3rhsp]{max-width:740px;padding-bottom:var(--s-7);position:relative}.prose[data-astro-cid-2vg3rhsp]{font-size:var(--step-1);color:var(--ink);line-height:1.7}.prose[data-astro-cid-2vg3rhsp] h2{border-top:1px solid var(--grid);font-size:var(--step-4);margin-top:var(--s-8);padding-top:var(--s-6);line-height:1.2;position:relative}.prose[data-astro-cid-2vg3rhsp] h2:before{background:var(--formula);content:"";width:56px;height:4px;position:absolute;top:-1px;left:0}.prose[data-astro-cid-2vg3rhsp] h2:first-child{border-top:none;margin-top:0;padding-top:0}.prose[data-astro-cid-2vg3rhsp] h2:first-child:before{display:none}.prose[data-astro-cid-2vg3rhsp] h3{font-size:var(--step-2);margin-block:var(--s-5) var(--s-2)}.prose[data-astro-cid-2vg3rhsp] p{margin-block:var(--s-4)}.prose[data-astro-cid-2vg3rhsp] ul,.prose[data-astro-cid-2vg3rhsp] ol{margin-block:var(--s-3);padding-left:var(--s-4)}.prose[data-astro-cid-2vg3rhsp] li{margin-block:var(--s-1)}.prose[data-astro-cid-2vg3rhsp] strong{font-weight:600}.prose[data-astro-cid-2vg3rhsp] a{color:var(--formula-text);text-underline-offset:2px;text-decoration:underline}.prose[data-astro-cid-2vg3rhsp] table{border-collapse:collapse;margin-block:var(--s-4);width:100%}.prose[data-astro-cid-2vg3rhsp] th,.prose[data-astro-cid-2vg3rhsp] td{border:1px solid var(--grid);text-align:left;font-size:var(--step-0);padding:8px 12px}.prose[data-astro-cid-2vg3rhsp] th{background:var(--paper-2);font-family:var(--font-mono)}.prose[data-astro-cid-2vg3rhsp] code{font-family:var(--font-mono);background:var(--paper-2);border-radius:var(--radius);color:var(--formula-text);padding:2px 6px;font-size:.9em}.prose[data-astro-cid-2vg3rhsp] pre{font-family:var(--font-mono);background:var(--paper-2);border:1px solid var(--grid-strong);padding:var(--s-3) var(--s-4);border-radius:var(--radius);margin-block:var(--s-3);font-size:var(--step-0);line-height:1.6;overflow-x:auto}.prose[data-astro-cid-2vg3rhsp] pre code{color:var(--formula-text);background:0 0;padding:0}.prose[data-astro-cid-2vg3rhsp] .ebook-figure{margin-block:var(--s-5)}.prose[data-astro-cid-2vg3rhsp] .ebook-figure img{border:1px solid var(--grid-strong);border-radius:var(--radius-lg);box-shadow:var(--shadow-md);width:100%;max-width:100%;height:auto;display:block}.prose[data-astro-cid-2vg3rhsp] .ebook-figure figcaption{color:var(--ink-soft);font-size:var(--step--1);margin-top:var(--s-2);text-align:center;line-height:1.5}.eb-article__end[data-astro-cid-2vg3rhsp]{background:var(--formula-tint);border-radius:var(--radius-lg);align-items:center;gap:var(--s-4);margin-top:var(--s-7);padding:var(--s-5);flex-wrap:wrap;justify-content:space-between;display:flex}.eb-article__end[data-astro-cid-2vg3rhsp] p[data-astro-cid-2vg3rhsp]{color:var(--ink);margin:0;font-weight:500}.eb-email-form[data-astro-cid-2vg3rhsp]{width:100%;margin-top:8px}.eb-email-form--end[data-astro-cid-2vg3rhsp]{margin-top:4px}.eb-email-form__label[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-size:var(--step--1);margin:0 0 6px}.eb-email-form__row[data-astro-cid-2vg3rhsp]{gap:8px;display:flex}.eb-email-form__row[data-astro-cid-2vg3rhsp] input[data-astro-cid-2vg3rhsp]{background:var(--paper-2);border:1px solid var(--grid);font-size:var(--step--1);min-width:0;min-height:40px;padding:0 var(--s-3);transition:border-color .15s var(--ease), box-shadow .15s var(--ease);border-radius:8px;flex:1}.eb-email-form__row[data-astro-cid-2vg3rhsp] input[data-astro-cid-2vg3rhsp]:focus-visible{border-color:var(--formula);box-shadow:0 0 0 3px var(--formula-tint);outline:none}.eb-email-form__row[data-astro-cid-2vg3rhsp] button[data-astro-cid-2vg3rhsp]{background:var(--paper);border:1px solid var(--grid-strong);color:var(--ink);cursor:pointer;font-size:var(--step--1);min-height:40px;transition:background .15s var(--ease), border-color .15s var(--ease);border-radius:8px;flex:none;padding:0 18px;font-weight:600}.eb-email-form__row[data-astro-cid-2vg3rhsp] button[data-astro-cid-2vg3rhsp]:hover{background:var(--paper-2);border-color:var(--formula)}.eb-email-form__row[data-astro-cid-2vg3rhsp] button[data-astro-cid-2vg3rhsp]:disabled{cursor:not-allowed;opacity:.6}.eb-email-form__status[data-astro-cid-2vg3rhsp]{color:var(--formula-text);font-size:var(--step--1);min-height:1.3em;margin:6px 0 0}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav{border-top:1px solid var(--grid);gap:var(--s-4);margin-block:var(--s-7) var(--s-2);padding-top:var(--s-4);justify-content:space-between;display:flex}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav__link{box-sizing:border-box;flex-direction:column;justify-content:center;gap:2px;max-width:48%;min-height:44px;padding:8px 4px;text-decoration:none;display:flex}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav__link--next{text-align:right;align-items:flex-end;margin-left:auto}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav__dir{color:var(--formula-text);font-size:var(--step--1);font-weight:700}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav__label{color:var(--ink);font-size:var(--step-0);line-height:1.3}.prose[data-astro-cid-2vg3rhsp] .eb-chapnav__link:hover .eb-chapnav__label{text-decoration:underline}.eb-progress[data-astro-cid-2vg3rhsp]{pointer-events:none;z-index:90;background:0 0;height:3px;position:fixed;top:0;left:0;right:0}.eb-progress__bar[data-astro-cid-2vg3rhsp]{background:var(--formula);width:0%;height:100%}.eb-toolbar[data-astro-cid-2vg3rhsp]{bottom:var(--s-4);gap:var(--s-2);left:var(--s-4);z-index:55;flex-direction:column;display:flex;position:fixed}@media (width<=640px){.eb-toolbar[data-astro-cid-2vg3rhsp]{bottom:calc(var(--s-3) + 44px + var(--s-3))}}.eb-toolbar__btn[data-astro-cid-2vg3rhsp]{background:var(--paper);border:1px solid var(--grid-strong);box-shadow:var(--shadow-md);color:var(--ink);cursor:pointer;font-family:var(--font-body);font-size:var(--step--1);border-radius:999px;align-items:center;gap:8px;min-height:44px;padding:0 16px;font-weight:600;display:inline-flex}.eb-toolbar__btn[data-astro-cid-2vg3rhsp]:hover{background:var(--paper-2);border-color:var(--ink-soft)}.eb-toolbar__top[data-astro-cid-2vg3rhsp]{justify-content:center;min-width:44px;padding:0}.eb-toolbar__count[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-family:var(--font-mono)}.eb-nav-panel[data-astro-cid-2vg3rhsp]{background:var(--paper);border:1px solid var(--grid-strong);border-radius:var(--radius-lg);bottom:calc(var(--s-4) + 96px + var(--s-3));box-shadow:var(--shadow-lg);left:var(--s-4);opacity:0;pointer-events:none;max-width:320px;max-height:min(60vh,520px);transition:opacity .2s var(--ease), transform .2s var(--ease);width:calc(100vw - var(--s-4) * 2);z-index:56;position:fixed;overflow-y:auto;transform:translateY(10px)}@media (width<=640px){.eb-nav-panel[data-astro-cid-2vg3rhsp]{bottom:calc(var(--s-3) + 44px + var(--s-3) + 96px + var(--s-3))}}.eb-nav-panel[data-astro-cid-2vg3rhsp][data-state=open]{opacity:1;pointer-events:auto;transform:translateY(0)}.eb-nav-panel__head[data-astro-cid-2vg3rhsp]{background:var(--paper);border-bottom:1px solid var(--grid);padding:var(--s-3) var(--s-4);justify-content:space-between;align-items:center;display:flex;position:sticky;top:0}.eb-nav-panel__progress[data-astro-cid-2vg3rhsp]{color:var(--ink-soft);font-size:var(--step--1);margin:0;font-weight:600}.eb-nav-panel__close[data-astro-cid-2vg3rhsp]{border-radius:var(--radius);color:var(--ink-soft);cursor:pointer;font-size:var(--step-1);background:0 0;border:0;justify-content:center;align-items:center;width:44px;height:44px;margin:-10px -10px -10px 0;line-height:1;display:inline-flex}.eb-nav-panel__close[data-astro-cid-2vg3rhsp]:hover{background:var(--paper-2);color:var(--ink)}.eb-nav-panel__list[data-astro-cid-2vg3rhsp]{padding:var(--s-2) var(--s-3) var(--s-3);margin:0;list-style:none}.eb-nav-panel__list[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp]{border-radius:var(--radius);box-sizing:border-box;color:var(--ink);font-size:var(--step--1);align-items:center;min-height:44px;padding:8px 10px;text-decoration:none;display:flex}.eb-nav-panel__list[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp]:hover{background:var(--paper-2)}.eb-nav-panel__list[data-astro-cid-2vg3rhsp] a[data-astro-cid-2vg3rhsp][aria-current=true]{background:var(--formula-tint);color:var(--formula-text);font-weight:700}@media (prefers-reduced-motion:reduce){.eb-nav-panel[data-astro-cid-2vg3rhsp]{transition:none}}@media print{.hdr,.ftr,.donate-bar,.source-rail,.skip-link,[id^=popup-]{display:none!important}html,body{background:#fff}.wrap[data-astro-cid-2vg3rhsp]{max-width:100%}.eb-cover__actions[data-astro-cid-2vg3rhsp],.share{display:none!important}.eb-cover[data-astro-cid-2vg3rhsp]{break-after:page;flex-direction:column;justify-content:center;align-items:center;gap:0;min-height:9in;display:flex}.eb-cover__copy[data-astro-cid-2vg3rhsp] .cellref,.eb-cover__desc[data-astro-cid-2vg3rhsp],.eb-cover__meta[data-astro-cid-2vg3rhsp]{display:none!important}.eb-cover__title[data-astro-cid-2vg3rhsp]{clip-path:inset(50%);width:1px;height:1px;position:absolute;overflow:hidden}.eb-cover__art[data-astro-cid-2vg3rhsp]{width:100%;max-width:100%;height:100%}.eb-toc[data-astro-cid-2vg3rhsp]{break-after:page;background:0 0;border:none;padding:0}.eb-toc__list[data-astro-cid-2vg3rhsp]{columns:1}.eb-article__end[data-astro-cid-2vg3rhsp]{display:none!important}.prose[data-astro-cid-2vg3rhsp]{font-variant-ligatures:none;font-feature-settings:"liga" 0, "calt" 0;max-width:6.5in;margin-inline:auto;font-size:11.5pt;line-height:1.5}.prose[data-astro-cid-2vg3rhsp] h2{break-before:page;break-after:avoid-page;border-top:none;margin-top:0;padding-top:0}.prose[data-astro-cid-2vg3rhsp] h2:first-child{break-before:avoid-page}.prose[data-astro-cid-2vg3rhsp] h2:before{display:none}.prose[data-astro-cid-2vg3rhsp] p,.prose[data-astro-cid-2vg3rhsp] li,.prose[data-astro-cid-2vg3rhsp] .ebook-figure{break-inside:avoid}.prose[data-astro-cid-2vg3rhsp] .ebook-figure img{box-shadow:none}.prose[data-astro-cid-2vg3rhsp] pre{white-space:pre-wrap;word-break:break-word;overflow-x:visible}.eb-progress[data-astro-cid-2vg3rhsp],.eb-toolbar[data-astro-cid-2vg3rhsp],.eb-nav-panel[data-astro-cid-2vg3rhsp],.prose[data-astro-cid-2vg3rhsp] .eb-chapnav{display:none!important}}