body { font-family: 'Inter', sans-serif; background-color: #f0f9ff; }
.tab-content { display: none; }
.tab-content.active { display: block; }
.tab { transition: all 0.3s ease; text-align: left; width: 100%; }
.tab.active { color: #2563eb; border-left-color: #2563eb; background-color: #eef2ff; }
@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
.tab-content.active { animation: fadeIn 0.5s ease-in-out; }
#pg_strength_bar > div { transition: width 0.3s ease-in-out; }
.nav-group-title { padding: 1rem 1.25rem 0.5rem; font-size: 0.75rem; font-weight: 700; text-transform: uppercase; letter-spacing: 0.05em; color: #6b7280; cursor: pointer; display: flex; justify-content: space-between; align-items: center; }
.nav-group-title::after { content: '▾'; transition: transform 0.2s; }
details[open] > summary.nav-group-title::after { transform: rotate(180deg); }
.tab-navigation-scroll { -ms-overflow-style: none; scrollbar-width: none; }
.tab-navigation-scroll::-webkit-scrollbar { display: none; }
.markdown-preview h1, .markdown-preview h2, .markdown-preview h3 { border-bottom: 1px solid #e5e7eb; padding-bottom: 0.3em; margin-top: 1em; margin-bottom: 0.5em; }
.markdown-preview h1 { font-size: 2em; } .markdown-preview h2 { font-size: 1.5em; } .markdown-preview h3 { font-size: 1.2em; }
.markdown-preview p { margin-bottom: 1em; } .markdown-preview a { color: #2563eb; }
.markdown-preview code { background-color: #f3f4f6; padding: 0.2em 0.4em; margin: 0; font-size: 85%; border-radius: 6px; }
.markdown-preview pre { background-color: #1f2937; color: #d1d5db; padding: 1em; border-radius: 8px; overflow-x: auto; }
.markdown-preview pre code { background-color: transparent; padding: 0; }
.markdown-preview blockquote { border-left: 4px solid #d1d5db; padding-left: 1em; color: #6b7280; margin-left: 0; }
.markdown-preview ul, .markdown-preview ol { padding-left: 2em; margin-bottom: 1em; } .markdown-preview li { margin-bottom: 0.25em; }
#sig_pad { touch-action: none; background-image: repeating-conic-gradient(#f3f4f6 0% 25%, transparent 0% 50%); background-size: 20px 20px; }
.calc-btn { transition: background-color 0.2s ease; }
.calc-btn:hover { background-color: #dbeafe; }
.calc-btn.operator { background-color: #dbeafe; }
.calc-btn.operator:hover { background-color: #bfdbfe; }
.calc-btn.equals { background-color: #2563eb; color: white; }
.calc-btn.equals:hover { background-color: #1d4ed8; }
@keyframes flip { 0% { transform: rotateY(0); } 100% { transform: rotateY(1080deg); } }
.flipping { animation: flip 0.6s ease-out; }
.copy-btn { background-color: #e5e7eb; padding: 2px 8px; border-radius: 4px; font-size: 0.8rem; color: #4b5563; }
.copy-btn:hover { background-color: #d1d5db; }