body {
    font-family: 'Noto Sans TC', sans-serif;
    scroll-behavior: smooth;
    background-color: #F6F8FA;
}
:root {
    --gh-blue: #0969da;
    --gh-blue-hover: #0349b4;
    --gh-green: #2da44e;
    --gh-purple: #8250df;
    --gh-dark: #24292f;
    --gh-gray: #57606a;
}
.text-gh-blue { color: var(--gh-blue); }
.text-gh-green { color: var(--gh-green); }
.text-gh-purple { color: var(--gh-purple); }
.text-gh-dark { color: var(--gh-dark); }

.bg-gh-blue { background-color: var(--gh-blue); }
.bg-gh-green { background-color: var(--gh-green); }
.bg-gh-purple { background-color: var(--gh-purple); }
.bg-gh-dark { background-color: var(--gh-dark); }
.nav-item { border-bottom: 3px solid transparent; }
.nav-item.active {
    border-bottom: 3px solid var(--gh-blue);
    color: var(--gh-dark);
    font-weight: 600;
}
.fade-in {
    animation: fadeIn 0.4s cubic-bezier(0.1, 0.9, 0.2, 1);
}
@keyframes fadeIn {
    from { opacity: 0; transform: translateY(8px); }
    to { opacity: 1; transform: translateY(0); }
}
.no-scrollbar::-webkit-scrollbar { display: none; }
.no-scrollbar { -ms-overflow-style: none; scrollbar-width: none; }

.gh-card {
    box-shadow: 0 1px 3px rgba(27,31,36,0.12), 0 8px 24px rgba(27,31,36,0.08);
    border: 1px solid #d0d7de;
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}
.gh-card:hover {
    box-shadow: 0 4px 12px rgba(27,31,36,0.15), 0 12px 28px rgba(27,31,36,0.1);
    transform: translateY(-2px);
}