.ipas-refero-root{--ipas-shell-max: 72rem;--ipas-reading-max: 54rem;--ipas-shell-padding-inline: clamp(1rem, 3vw, 1.5rem);--ipas-shell-gap: 2rem;--ipas-header-row-height: 3.25rem;--ipas-tabs-row-height: 2.5rem}.ipas-shell__inner{width:min(100%,var(--ipas-shell-max));margin-inline:auto;padding-inline:var(--ipas-shell-padding-inline)}.ipas-shell__header{position:sticky;top:0;z-index:40;border-bottom:1px solid var(--border-soft);background:var(--nav-bg);backdrop-filter:blur(.75rem)}.ipas-shell__header-inner{display:grid;grid-template-areas:"brand utility" "nav nav";align-items:center;gap:.75rem 1rem;padding-block:.625rem}.ipas-shell__header-inner--exam{grid-template-areas:"brand utility" "switcher switcher"}.ipas-shell__brand{grid-area:brand;display:inline-flex;align-items:center;min-height:var(--ipas-header-row-height);min-width:0;color:var(--text-primary);font-size:1rem;line-height:1.2;font-weight:600;letter-spacing:-.01em;text-decoration:none;white-space:nowrap}.ipas-primary-nav{grid-area:nav;min-width:0}.ipas-primary-nav__list{display:flex;flex-wrap:wrap;align-items:center;gap:.5rem}.ipas-shell__switcher-slot{grid-area:switcher;min-width:0}.ipas-primary-nav__link,.ipas-level-switcher__link,.ipas-auth-link{display:inline-flex;align-items:center;justify-content:center;min-height:2.375rem;min-width:0;padding-inline:.875rem;border:1px solid var(--border-soft);border-radius:999px;background:color-mix(in srgb,var(--text-primary) 2%,transparent);color:var(--text-secondary);font-size:.9375rem;line-height:1;font-weight:500;text-align:center;text-decoration:none;white-space:nowrap;word-break:keep-all;overflow-wrap:normal;transition:color .16s ease,background-color .16s ease,border-color .16s ease}.ipas-primary-nav__link[data-active=true],.ipas-level-switcher__link[data-active=true]{color:var(--nav-active-text);background:var(--nav-active-bg);border-color:var(--nav-active-bg)}.ipas-level-switcher{min-width:0}.ipas-segmented{display:inline-flex;gap:4px;padding:4px;border-radius:999px;background:var(--bg-muted)}.ipas-segmented>:is(a,button,label){flex:1 1 0;min-width:0;text-align:center;border-radius:999px;padding:8px 24px;font-size:15px;font-weight:500;text-decoration:none;transition:background .12s ease,color .12s ease;cursor:pointer;border:none}.ipas-segmented>.ref-btn-primary{background:var(--cta-bg);color:var(--cta-text)}.ipas-segmented>.ref-btn-secondary{background:transparent;color:var(--text-secondary);border:none}.ipas-segmented>.ref-btn-secondary:hover{background:color-mix(in srgb,var(--text-primary) 6%,transparent)}.ipas-choice-grid>:is(a,button,label){width:100%;min-width:0}.ipas-level-switcher__link{padding-inline:.75rem}.ipas-shell__section-row{border-top:1px solid var(--border-soft);overflow-x:hidden}.ipas-primary-nav__link:hover,.ipas-level-switcher__link:hover,.ipas-auth-link:hover,.ipas-shell__utility-link:hover,.ipas-subnav__link:hover{color:var(--nav-text-hover)}.ipas-shell__utility{display:flex;align-items:center;justify-content:flex-end;gap:.5rem;min-width:0}.ipas-shell__utility-links{display:none;align-items:center;justify-content:flex-end;gap:.25rem}.ipas-shell__utility-link{display:inline-flex;align-items:center;justify-content:center;min-height:2.375rem;padding-inline:.625rem;border-radius:999px;color:var(--text-secondary);font-size:.9375rem;line-height:1;font-weight:500;text-decoration:none;transition:color .16s ease,background-color .16s ease}.ipas-shell__utility-link[data-active=true]{background:color-mix(in srgb,var(--text-primary) 4%,transparent);color:var(--text-primary)}.ipas-auth-slot,.ipas-auth-group{display:flex;align-items:center;justify-content:flex-end;gap:.5rem;min-width:0}.ipas-auth-link,.ipas-auth-group>:is(a,button){flex:0 1 auto;max-width:min(14rem,48vw);overflow:hidden;text-overflow:ellipsis}.ipas-shell__utility button[aria-label*=色彩模式]{width:2.5rem;min-width:2.5rem;height:2.5rem;min-height:2.375rem;border:1px solid var(--border-soft);border-radius:999px;background:color-mix(in srgb,var(--text-primary) 2%,transparent)}.ipas-main{max-width:var(--ipas-shell-max);padding-block:1.75rem 2.75rem}.ipas-subnav{margin:0;max-width:100%;overflow-x:auto;overflow-y:hidden;scrollbar-width:none;-webkit-overflow-scrolling:touch}.ipas-subnav::-webkit-scrollbar{display:none}.ipas-subnav__list{display:inline-flex;align-items:center;gap:.375rem;min-width:max-content;padding-block:.3125rem}.ipas-subnav__link{position:relative;display:inline-flex;flex:0 0 auto;align-items:center;min-width:0;min-height:var(--ipas-tabs-row-height);padding-inline:.875rem;color:var(--text-secondary);font-size:.9375rem;line-height:1;font-weight:500;text-decoration:none;white-space:nowrap;word-break:keep-all;overflow-wrap:normal}.ipas-subnav__link:after{content:"";position:absolute;right:.875rem;bottom:.375rem;left:.875rem;height:.125rem;border-radius:999px;background:transparent}.ipas-subnav__link[data-active=true]{color:var(--text-primary);font-weight:600}.ipas-subnav__link[data-active=true]:after{background:var(--text-primary)}.ipas-choice-grid{display:grid;gap:1rem;grid-template-columns:1fr}.ipas-chip-row{display:flex;flex-wrap:wrap;gap:.5rem}.ipas-chip-row>*{flex:0 0 auto;max-width:100%}.ipas-action-row{display:flex;flex-wrap:wrap;gap:.75rem}.ipas-action-row>*{flex:0 0 auto}.ipas-template-pre-hero{margin-bottom:1rem}.ipas-template-hero:not(:empty){margin-bottom:2rem}.ipas-template-body{color:var(--text-primary)}.ipas-template-body>*+*{margin-top:var(--ipas-shell-gap)}[data-refero] .ipas-main h1,[data-refero] .ipas-main .display-title{font-size:clamp(2rem,5.8vw,3rem);line-height:1.12;letter-spacing:-.02em;text-wrap:balance}[data-refero] .ipas-main h2,[data-refero] .ipas-main .h2-spec{font-size:clamp(1.625rem,4vw,2rem);line-height:1.24;text-wrap:balance}[data-refero] .ipas-main h3{font-size:1.375rem;line-height:1.35}[data-refero] .ipas-main .page-hero{margin-top:.75rem;margin-bottom:1.5rem;max-width:var(--ipas-shell-max)}[data-refero] .ipas-main .page-hero>:is(.eyebrow,h1){max-width:var(--ipas-reading-max)}[data-refero] .ipas-main .page-hero p,[data-refero] .ipas-main .ref-card>p{max-width:var(--ipas-reading-max);text-wrap:pretty}[data-refero] .ipas-main .section>p{max-width:var(--ipas-shell-max);text-wrap:auto}[data-refero] .ipas-main .page-hero p{max-width:var(--ipas-shell-max);text-wrap:auto}[data-refero].ipas-refero-root .ipas-main .page-hero p{max-width:var(--ipas-shell-max)}[data-refero] .ipas-main .section{margin-block:2rem}[data-refero] .ipas-main .section+.section{margin-top:2.5rem}[data-refero] .ipas-main .ref-card{padding:clamp(1.125rem,3vw,1.5rem)}[data-refero] .ipas-main .ref-card p,[data-refero] .ipas-main .ref-card li{line-height:1.7}[data-refero] .ipas-main .ipas-helper,[data-refero] .ipas-main .ipas-meta{font-size:.9375rem;line-height:1.65;color:var(--text-secondary)}[data-refero] .ipas-main .ipas-kicker{font-size:.8125rem;line-height:1.4;font-weight:500;color:var(--text-muted)}[data-refero] .ipas-main .ipas-price{font-family:var(--font-sans);font-size:1.375rem;line-height:1.35;font-weight:500;color:var(--text-primary)}[data-refero] .ipas-main .ipas-price-note{font-size:.8125rem;line-height:1.5;color:var(--text-muted)}[data-refero] .ipas-main .ipas-deepdive-actions{display:flex;flex-wrap:wrap;gap:.75rem;margin-top:1.5rem}[data-refero] .ipas-main .ipas-feature-grid{display:grid;gap:1.5rem}[data-refero] .ipas-main .ipas-faq-list{display:grid;gap:.75rem}[data-refero] .ipas-main .ipas-faq-item summary{cursor:pointer;list-style:none;color:var(--text-primary)}[data-refero] .ipas-main .ipas-faq-item summary::-webkit-details-marker{display:none}[data-refero] .ipas-main .ipas-faq-question{display:flex;align-items:center;justify-content:space-between;gap:1rem;font-family:var(--font-sans);font-size:1.125rem;line-height:1.45;font-weight:500}[data-refero] .ipas-main .ipas-faq-question:after{content:"+";flex:0 0 auto;color:var(--text-muted);font-size:1.25rem;line-height:1}[data-refero] .ipas-main .ipas-faq-item[open] .ipas-faq-question:after{content:"−"}[data-refero] .ipas-main #learner-status-card{display:grid;gap:1.125rem;padding:1.25rem}[data-refero] .ipas-main #learner-status-card .heading-row,[data-refero] .ipas-main #learner-status-body{grid-column:1}[data-refero] .ipas-main #learner-status-card .card-text-spec{max-width:var(--ipas-reading-max);font-size:.875rem;line-height:1.6}[data-refero] .ipas-main #learner-status-cta{display:flex;flex-wrap:wrap;gap:.625rem;padding:0}@media(min-width:40rem){.ipas-shell__utility-links{display:flex}.ipas-main{padding-block:2rem 3rem}}@media(min-width:48rem){.ipas-shell__header-inner{grid-template-columns:auto minmax(0,1fr) auto;grid-template-areas:"brand nav utility";gap:1rem;padding-block:.25rem}.ipas-shell__header-inner--exam{grid-template-areas:"brand switcher utility"}.ipas-primary-nav{justify-self:center;width:100%}.ipas-primary-nav__link,.ipas-level-switcher__link,.ipas-auth-link,.ipas-shell__utility-link,.ipas-subnav__link{min-height:2.25rem}.ipas-primary-nav__list{justify-content:center}.ipas-shell__utility{flex-wrap:nowrap}.ipas-subnav__list{padding-block:0}.ipas-choice-grid{grid-template-columns:repeat(2,minmax(0,1fr))}[data-refero] .ipas-main #learner-status-card{grid-template-columns:minmax(0,1fr) minmax(15rem,auto);gap:1.125rem 2rem;align-items:center;padding:1.75rem 2rem}[data-refero] .ipas-main #learner-status-cta{grid-column:2;grid-row:1 / span 2;justify-self:end;align-self:center;width:min(100%,17.5rem)}[data-refero] .ipas-main .progress-empty__actions{min-width:16rem;justify-items:stretch}}@media(max-width:39.99rem){.ipas-shell__brand{display:none}.ipas-shell__header-inner{grid-template-areas:"nav utility";grid-template-columns:1fr auto;gap:0 .5rem;padding-block:.5rem}.ipas-shell__header-inner--exam{grid-template-areas:"switcher utility";grid-template-columns:1fr auto}.ipas-primary-nav__list{flex-wrap:nowrap;gap:.25rem}.ipas-primary-nav__link,.ipas-level-switcher__link{font-size:.8125rem;padding-inline:.625rem;min-height:2rem}.ipas-shell__utility-links,.ipas-auth-slot{display:none}.ipas-shell__utility{gap:.25rem}[data-refero] .ipas-main .ref-card :is(p,li){font-size:1rem}[data-refero] .ipas-main .ipas-action-row>:is(a,button),[data-refero] .ipas-main .ipas-deepdive-actions>:is(a,button),[data-refero] .ipas-main .progress-empty__cta,[data-refero] .ipas-main #learner-status-cta>:is(a,button){width:100%}[data-refero] .ipas-main .ipas-faq-question{font-size:1.0625rem;align-items:flex-start}[data-refero] .ipas-main .ipas-deepdive-actions,.ipas-action-row{display:grid;gap:.625rem}}