.learn-root{min-height:var(--zza-viewport-height,100vh);background:var(--surface-primary);color:var(--fg-primary)}.learn-header{position:sticky;top:0;z-index:20;display:flex;align-items:center;gap:var(--space-control-gap);min-height:calc(var(--control-min-height) + var(--space-section-stack));padding:var(--space-control) var(--space-page-inline);background:color-mix(in srgb,var(--surface-primary) 92%,transparent);border-bottom:1px solid var(--surface-section-border);backdrop-filter:blur(var(--public-learn-header-blur));-webkit-backdrop-filter:blur(var(--public-learn-header-blur))}.learn-skip-link{position:fixed;top:var(--space-control);left:var(--space-page-inline);z-index:40;padding:var(--space-control) var(--space-card);transform:translateY(calc(-100% - var(--space-section)));border-radius:var(--radius-action);background:var(--fg-primary);color:var(--surface-primary);font-size:var(--type-body-sm);font-weight:800}.learn-skip-link:focus{transform:translateY(0)}.learn-brand,.learn-header nav a{display:inline-flex;align-items:center;color:var(--fg-primary);text-decoration:none}.learn-brand{gap:var(--space-control-gap);font-size:var(--type-section-title);font-weight:900}.learn-brand img{border-radius:var(--radius-control)}.learn-header nav{display:flex;align-items:center;gap:var(--space-field-gap);margin-left:auto}.learn-header nav a{gap:var(--space-field-gap);min-height:var(--control-min-height);padding:0 var(--space-control);border-radius:var(--radius-pill);color:var(--fg-secondary);font-size:var(--type-caption);font-weight:700}.learn-header nav a:first-child{background:var(--journey-current-soft);color:var(--journey-current)}.learn-app-cta,.learn-article,.learn-catalog,.learn-hero{padding-right:var(--space-page-inline);padding-left:var(--space-page-inline)}.learn-hero{padding-top:var(--public-learn-hero-block-space);padding-bottom:var(--public-learn-hero-block-space);text-align:center}.learn-kicker,.learn-section-heading>p{margin:0 0 var(--space-control-gap);color:var(--journey-current);font-size:var(--type-caption);font-weight:800;letter-spacing:var(--public-learn-kicker-tracking)}.learn-hero h1{margin:0;font-size:var(--public-learn-hero-title-size);line-height:var(--public-learn-display-line);letter-spacing:var(--public-learn-display-tracking);word-break:keep-all}.learn-hero h1 span{color:var(--journey-current);font-size:var(--public-learn-source-title-scale);letter-spacing:var(--public-learn-source-tracking)}.learn-hero>p:not(.learn-kicker){max-width:var(--public-learn-copy-max-width);margin:var(--space-section) auto 0;color:var(--fg-secondary);font-size:var(--type-body);line-height:var(--public-learn-reading-line);word-break:keep-all}.learn-hero-actions{display:flex;flex-wrap:wrap;justify-content:center;gap:var(--space-control-gap);margin-top:calc(var(--space-section) + var(--space-field-gap))}.learn-app-cta a,.learn-primary-action,.learn-secondary-action{display:inline-flex;align-items:center;justify-content:center;gap:var(--space-field-gap);min-height:var(--control-min-height);padding:0 var(--space-section-stack);border-radius:var(--radius-action);font-size:var(--type-body-sm);font-weight:800;text-decoration:none}.learn-app-cta a,.learn-primary-action{background:var(--fg-primary);color:var(--surface-primary)}.learn-secondary-action{color:var(--fg-primary);background:var(--journey-surface);border:1px solid var(--journey-border)}.learn-method{display:grid;gap:var(--space-control);padding:var(--space-section) var(--space-page-inline);background:var(--surface-section);border-block:1px solid var(--surface-section-border)}.learn-method>div{padding:var(--space-card);background:var(--journey-surface);border:1px solid var(--journey-border);border-radius:var(--radius-card)}.learn-method svg{color:var(--journey-current)}.learn-method h2{margin:var(--space-control-gap) 0 var(--space-field-gap);font-size:var(--type-section-title)}.learn-method p{margin:0;color:var(--fg-secondary);font-size:var(--type-body-sm);line-height:var(--public-learn-supporting-line)}.learn-catalog{padding-top:var(--public-learn-section-block-space);padding-bottom:var(--public-learn-section-block-space)}.learn-section-heading{margin-bottom:var(--space-section-stack)}.learn-section-heading h2{margin:0;font-size:var(--type-page-title)}.learn-section-heading span{display:block;margin-top:var(--space-field-gap);color:var(--fg-tertiary);font-size:var(--type-caption)}.learn-story-list{display:grid;gap:var(--public-learn-card-gap)}.learn-story-card{display:grid;grid-template-columns:var(--public-learn-thumb-size) minmax(0,1fr);gap:var(--space-control-gap) var(--space-card);padding:var(--space-card);background:var(--journey-surface);border:1px solid var(--journey-border);border-radius:var(--radius-card);box-shadow:var(--journey-shadow)}.learn-story-thumb{display:grid;place-items:center;width:var(--public-learn-thumb-size);height:var(--public-learn-thumb-size);border-radius:var(--radius-action);color:var(--journey-current);background:var(--journey-current-soft);font-size:var(--type-panel-title);font-weight:900;letter-spacing:var(--public-learn-source-tracking)}.learn-story-thumb-beginner{color:var(--journey-complete);background:var(--journey-complete-soft)}.learn-story-thumb-intermediate{color:var(--flow-text-strong);background:var(--flow-bg)}.learn-story-thumb-advanced{color:var(--status-review-text);background:var(--status-review-bg)}.learn-story-card-content{min-width:0}.learn-story-title-row{display:flex;align-items:flex-start;gap:var(--space-control-gap)}.learn-story-title-row h3{min-width:0;flex:1}.learn-level{padding:var(--space-field-gap) var(--space-control-gap);border-radius:var(--radius-pill);font-size:var(--type-caption);font-weight:800}.learn-level-beginner{background:var(--journey-complete-soft);color:var(--journey-complete)}.learn-level-intermediate{background:var(--flow-bg);color:var(--flow-text-strong)}.learn-level-advanced{background:var(--status-review-bg);color:var(--status-review-text)}.learn-story-card h3{margin:0 0 var(--space-field-gap);font-size:var(--type-story-card-title);line-height:var(--public-learn-heading-line);word-break:keep-all}.learn-story-card p{margin:0;color:var(--fg-secondary);font-size:var(--type-body-sm);line-height:var(--public-learn-supporting-line);word-break:keep-all;overflow-wrap:break-word}.learn-story-card .learn-story-title-pinyin{color:var(--fg-tertiary);font-size:var(--type-caption);font-style:italic}.learn-story-card .learn-story-title-meaning{margin-top:var(--space-field-gap);color:var(--fg-secondary);font-weight:700}.learn-story-card-zone-b{display:flex;flex-wrap:wrap;align-items:center;justify-content:space-between;gap:var(--space-field-gap) var(--space-control-gap);margin-top:var(--space-control-gap);padding-top:var(--space-control-gap);border-top:1px solid var(--border-default);color:var(--fg-tertiary);font-size:var(--type-caption)}.learn-story-card-zone-b a{display:inline-flex;align-items:center;gap:var(--space-field-gap);min-height:var(--control-min-height);color:var(--journey-current);font-size:var(--type-body-sm);font-weight:800;text-decoration:none}.learn-story-description{grid-column:1/-1;padding-top:var(--space-control-gap);border-top:1px solid var(--border-default)}.learn-app-cta{padding-top:var(--public-learn-cta-block-space);padding-bottom:var(--public-learn-cta-block-space);background:var(--surface-section);border-block:1px solid var(--surface-section-border);text-align:center}.learn-app-cta h2{margin:0;font-size:var(--type-page-title);line-height:var(--public-learn-heading-line);word-break:keep-all}.learn-app-cta>p:not(.learn-kicker){margin:var(--space-control) auto var(--space-section-stack);color:var(--fg-secondary);font-size:var(--type-body-sm);line-height:var(--public-learn-reading-line)}.learn-footer{display:flex;flex-wrap:wrap;justify-content:center;gap:var(--space-control-gap) var(--space-section-stack);padding:var(--public-learn-footer-block-space) var(--space-page-inline);color:var(--fg-tertiary);font-size:var(--type-caption)}.learn-footer a{color:inherit;text-decoration:none}.learn-article{padding-top:calc(var(--space-section) + var(--space-control-gap));padding-bottom:calc(var(--space-section) + var(--space-field-gap))}.learn-back{display:inline-flex;align-items:center;gap:var(--space-field-gap);min-height:var(--control-min-height);color:var(--fg-secondary);font-size:var(--type-body-sm);font-weight:700;text-decoration:none}.learn-article-header{margin-top:calc(var(--space-section) + var(--space-field-gap))}.learn-article-header h1{margin:var(--space-card) 0 var(--space-control-gap);font-size:var(--type-story-detail-title);line-height:var(--public-learn-heading-line);letter-spacing:var(--public-learn-detail-tracking);word-break:keep-all}.learn-article-header>p{margin:0;color:var(--fg-secondary);font-size:var(--type-body);line-height:var(--public-learn-reading-line)}.learn-reviewed{display:inline-flex;align-items:center;gap:var(--space-field-gap);margin-top:var(--space-card);color:var(--journey-complete);font-size:var(--type-caption);font-weight:800}.learn-reading-guide{margin-top:calc(var(--space-section) + var(--space-control-gap));padding:var(--space-card);background:var(--surface-section);border:1px solid var(--surface-section-border);border-radius:var(--radius-card)}.learn-reading-guide h2{margin:0 0 var(--space-control-gap);font-size:var(--type-section-title)}.learn-reading-guide ol{margin:0;padding-left:var(--space-section);color:var(--fg-secondary);font-size:var(--type-body-sm);line-height:var(--public-learn-reading-line)}.learn-sentences{display:grid;gap:var(--public-learn-card-gap);margin:calc(var(--space-section) + var(--space-field-gap)) 0 0;padding:0;list-style:none}.learn-sentence-card{position:relative;padding:var(--space-section-stack) var(--space-card) var(--space-card);background:var(--journey-surface);border:1px solid var(--journey-border);border-radius:var(--radius-card)}.learn-sentence-number{position:absolute;top:calc(-1 * var(--space-control-gap));left:var(--space-card);display:grid;place-items:center;width:var(--situation-step-marker-size);height:var(--situation-step-marker-size);background:var(--journey-current);border-radius:var(--radius-pill);color:var(--journey-surface);font-size:var(--type-caption);font-weight:900}.learn-sentence-source{margin:0;font-size:var(--type-hanzi-card);font-weight:600;line-height:var(--public-learn-reading-line)}.learn-sentence-pinyin{margin:var(--space-control-gap) 0 0;color:var(--fg-tertiary);font-style:italic}.learn-sentence-meaning,.learn-sentence-pinyin{font-size:var(--type-body-sm);line-height:var(--public-learn-supporting-line)}.learn-sentence-meaning{margin:var(--space-control) 0 0;padding-top:var(--space-control);color:var(--fg-secondary);border-top:1px solid var(--border-default)}.learn-article-cta{margin:calc(var(--space-section-stack) * 2) calc(var(--space-page-inline) * -1) 0}.learn-root a:focus-visible{outline:var(--public-learn-focus-width) solid var(--accent);outline-offset:var(--public-learn-focus-offset)}@media (min-width:700px){body:has(.learn-root){--app-max-width:var(--public-learn-max-width)}.learn-method,.learn-story-list{grid-template-columns:repeat(2,minmax(0,1fr))}.learn-sentence-card{padding:var(--type-page-title) var(--space-section) var(--space-section-stack)}}@media (prefers-reduced-motion:reduce){.learn-root{scroll-behavior:auto}}