.course-filter {
    display: flex; gap: 0.75rem; flex-wrap: wrap;
    justify-content: center; margin-bottom: 2.5rem;
}
.filter-btn {
    padding: 0.45rem 1.1rem; background: transparent;
    border: 1px solid var(--border); border-radius: 20px;
    color: var(--text-secondary); font-size: 0.85rem;
    cursor: pointer; transition: var(--transition);
}
.filter-btn.active, .filter-btn:hover { background: var(--accent); border-color: var(--accent); color: white; }
.course-grid { display: grid; grid-template-columns: repeat(4,1fr); gap: 1.5rem; }
.course-card {
    background: var(--bg-card); border: 1px solid var(--border);
    border-radius: var(--radius); overflow: hidden; transition: var(--transition);
}
.course-card:hover { border-color: var(--border-hover); transform: translateY(-4px); box-shadow: 0 12px 40px rgba(0,0,0,0.3); }
.course-banner { height: 120px; display: flex; align-items: center; justify-content: center; position: relative; }
.course-icon { font-size: 3rem; color: rgba(255,255,255,0.3); }
.course-level {
    position: absolute; top: 0.75rem; right: 0.75rem;
    background: rgba(0,0,0,0.5); color: white;
    padding: 3px 8px; border-radius: 5px; font-size: 0.7rem; font-weight: 600;
}
.course-body { padding: 1.25rem; display: flex; flex-direction: column; gap: 0.6rem; }
.course-body h4 { font-size: 0.95rem; line-height: 1.4; }
.course-body p { color: var(--text-secondary); font-size: 0.82rem; }
.course-info { display: flex; gap: 0.75rem; flex-wrap: wrap; }
.course-info span { font-size: 0.75rem; color: var(--text-muted); display: flex; align-items: center; gap: 4px; }
.course-footer { display: flex; align-items: center; justify-content: space-between; margin-top: 0.5rem; }
.course-rating { color: #f59e0b; font-size: 0.75rem; display: flex; align-items: center; gap: 2px; }
.course-rating span { color: var(--text-secondary); margin-left: 3px; }
@media (max-width: 1100px) { .course-grid { grid-template-columns: repeat(2,1fr); } }
@media (max-width: 768px) { .course-grid { grid-template-columns: 1fr; } }