.problem-shell{--problem-ink:#172033;--problem-navy:#173b72;--problem-navy-dark:#0f2d59;--problem-cyan:#0a98b1;--problem-cyan-dark:#087c91;--problem-cyan-soft:#e8f6f8;--problem-blue-soft:#eef4fb;--problem-page:#f4f7fa;--problem-paper:#ffffff;--problem-line:#d8e0e9;--problem-line-soft:#e9eef3;--problem-muted:#667085;--problem-supplement:#f2f5f8;--problem-supplement-line:#93a4b7;--problem-image-placeholder:#cbd2da;--problem-error:#a53f3f;--problem-serif:var(--font-noto-serif-jp),"Noto Serif JP","Hiragino Mincho ProN","Yu Mincho",serif;background:var(--problem-page);color:var(--problem-ink);font-family:var(--font-noto-sans-jp),"Hiragino Sans","Yu Gothic",sans-serif;font-size:14px;line-height:1.85;width:100%}main:has(>.problem-shell){max-width:none;padding:0}body:has(.problem-shell) .site-mobile-consultation{display:none}body:has(dialog[open]) [data-problem-mobile-cta],body:has(header button[aria-expanded=true]) [data-problem-mobile-cta],body[data-problem-overlay-open=true] 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ease}.problem-button:hover{background:var(--problem-navy-dark)}.problem-button--secondary{background:white;border-color:var(--problem-line);color:var(--problem-ink)}.problem-button--secondary:hover{background:white;border-color:var(--problem-cyan);color:var(--problem-cyan-dark)}.problem-text-button,.problem-view-all{display:inline-flex;gap:10px;align-items:center;min-height:44px;color:var(--problem-cyan-dark);text-decoration:underline;text-underline-offset:4px;font-size:13px;font-weight:700}.problem-empty{padding:40px 24px;background:white;border:1px solid var(--problem-line)}.problem-eyebrow{margin:0 0 12px;color:var(--problem-cyan-dark);font-family:var(--font-quicksand),sans-serif;font-weight:700;font-size:11px;letter-spacing:.16em}.problem-navigation{height:46px;background:white;border-bottom:1px solid var(--problem-line)}.problem-navigation-inner{height:100%;display:flex;align-items:center;justify-content:space-between;gap:16px}.problem-navigation-brand{font:700 14px/1.5 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p{margin:0;color:#4b5969;font-size:14px;line-height:2}.problem-home-support{margin-bottom:0}.problem-home-learning-link{display:flex;justify-content:flex-end;margin-top:20px}.problem-article-grid{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));align-items:start;gap:32px}.problem-media-card{display:block;min-width:0;background:white;border:1px solid var(--problem-line);box-shadow:0 10px 30px rgba(23,59,114,.045);transition:transform .16s ease,border-color .16s ease}.problem-media-card:hover{transform:translateY(-2px);border-color:#9faec1}.problem-media-card:hover .problem-media-card-title{color:var(--problem-cyan-dark)}.problem-media-card-title{margin:0;padding:17px 18px 20px;border-top:1px solid var(--problem-line-soft);font-size:14px;line-height:1.7;font-weight:700}.problem-home-popular{display:grid;grid-template-columns:repeat(2,minmax(0,1fr));column-gap:40px;list-style:none;padding:0}.problem-home-popular a{display:grid;grid-template-columns:32px 118px 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