body { font-family: 'Inter', sans-serif; background-color: #FDFBF7; color: #38332B; }
        h1, h2, h3, h4 { font-family: 'Zilla Slab', serif; }
        .station-card { background-color: #F2EAD3; border: 1px solid #DFD7BF; }
        .btn-primary { background-color: #A87C7C; color: white; transition: background-color 0.3s ease; }
        .btn-primary:hover { background-color: #8c6666; }
        .btn-primary:disabled { background-color: #c9b3b3; cursor: not-allowed; }
        .btn-secondary { background-color: #A0A083; color: white; transition: background-color 0.3s ease; }
        .btn-secondary:hover { background-color: #8a8a6e; }
        .topic-container > summary { cursor: pointer; font-family: 'Zilla Slab', serif; font-size: 1.5rem; font-weight: 600; padding: 1rem 1.5rem; background-color: #F2EAD3; border: 1px solid #DFD7BF; border-radius: 0.75rem; margin-top: 1.5rem; transition: background-color 0.2s ease; display: flex; justify-content: space-between; align-items: center; }
        .topic-container > summary:hover { background-color: #e3d5b8; }
        .topic-container[open] > summary { border-bottom-left-radius: 0; border-bottom-right-radius: 0; }
        .topic-content { padding: 1.5rem; border: 1px solid #DFD7BF; border-top: none; border-bottom-left-radius: 0.75rem; border-bottom-right-radius: 0.75rem; background-color: #FDFBF7; }
        .solution-box { background-color: rgba(255, 255, 255, 0.8); border: 1px solid #DFD7BF; border-left: 3px solid #A87C7C; padding: 1rem; margin-top: 1rem; border-radius: 0.5rem; }
        code { background-color: rgba(168, 124, 124, 0.1); color: #A87C7C; padding: 0.1em 0.3em; border-radius: 4px; }
        .diff-table { font-family: monospace; text-align: center; }
        .diff-table td { padding: 0.5rem 1rem; }
        .diff-table .leading-diagonal { background-color: rgba(168, 124, 124, 0.2); }