::-webkit-scrollbar { width: 6px; height: 6px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: #374151; border-radius: 3px; }
::-webkit-scrollbar-thumb:hover { background: #4b5563; }
.collapsible-content.hidden { display: none; }
.arrow { display: inline-block; transition: transform 0.2s; font-size: 0.65em; }
.arrow.open { transform: rotate(90deg); }
.tool-header:hover { filter: brightness(1.15); }
.step-card pre { tab-size: 4; }
html { scroll-behavior: smooth; }