.topic-banner-hero {
    position: relative;
    border-radius: 2.5rem;
    padding: 3rem 2rem;
    background: radial-gradient(circle at 80% 20%, rgba(255,255,255,.15) 0%, transparent 60%),
                linear-gradient(135deg, rgb(var(--primary)) 0%, rgb(var(--secondary)) 100%);
    color: #ffffff;
    box-shadow: 0 25px 50px -12px rgba(var(--primary), .35);
    overflow: hidden;
    margin-bottom: 2rem;
}
@media (min-width: 768px) { .topic-banner-hero { border-radius: 3.5rem; padding: 4rem 3.5rem; } }

.topic-search-box {
    background-color: rgba(var(--surface-container-lowest),1);
    border: 2px solid rgba(var(--surface-container-high),1);
    border-radius: 9999px;
    padding: .6rem 1.25rem;
    display: flex; align-items: center; gap: .75rem;
    box-shadow: 0 4px 20px rgba(0,0,0,.03);
    transition: all .25s ease;
}
.topic-search-box:focus-within { border-color: rgb(var(--primary)); box-shadow: 0 8px 30px rgba(var(--primary),.15); }

.lesson-card-item {
    background-color: rgba(var(--surface-container-lowest),1);
    border: 2px solid rgba(var(--surface-container-high),1);
    border-radius: 1.75rem;
    padding: 1.5rem;
    transition: all .3s cubic-bezier(.22,1,.36,1);
    position: relative;
    box-shadow: 0 4px 20px rgba(0,0,0,.02);
}
.lesson-card-item:hover {
    transform: translateY(-4px);
    border-color: rgba(var(--primary),.35);
    box-shadow: 0 14px 35px rgba(var(--primary),.12);
}
.lesson-card-item.active-step {
    border-color: rgb(var(--primary));
    background: linear-gradient(135deg, rgba(var(--primary),.04) 0%, rgba(var(--surface-container-lowest),1) 100%);
}

.lesson-step-badge {
    width: 3.25rem; height: 3.25rem; border-radius: 1.25rem;
    background: rgba(var(--primary),.1);
    color: rgb(var(--primary));
    font-weight: 900; font-size: 1.1rem;
    display: flex; align-items: center; justify-content: center; flex-shrink: 0;
    transition: all .3s ease;
}
.lesson-card-item:hover .lesson-step-badge {
    background: rgb(var(--primary));
    color: #ffffff;
    transform: scale(1.1) rotate(-6deg);
}

.sidebar-widget-card {
    background-color: rgba(var(--surface-container-lowest),1);
    border: 2px solid rgba(var(--surface-container-high),1);
    border-radius: 1.75rem;
    padding: 1.5rem;
    box-shadow: 0 4px 20px rgba(0,0,0,.02);
}