/**
 * KPN (知识点网络) 组件样式
 */

.kpn-visualizer {
    width: 100%;
}

.kpn-empty {
    text-align: center;
    padding: 60px 20px;
    color: var(--ls-text-secondary);
}

.kpn-empty i {
    font-size: 3rem;
    margin-bottom: 16px;
    opacity: 0.5;
}

.kpn-level {
    margin-bottom: 40px;
}

.kpn-level-title {
    display: flex;
    align-items: center;
    gap: 12px;
    font-size: 1.5rem;
    margin-bottom: 24px;
    color: var(--ls-text-primary);
    font-weight: 700;
}

.kpn-level-title i {
    color: var(--ls-primary);
}

.kpn-count {
    background: var(--ls-primary-light);
    color: var(--ls-primary);
    padding: 4px 12px;
    border-radius: 99px;
    font-size: 0.9rem;
    font-weight: 600;
    margin-left: auto;
}

.kpn-nodes-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(280px, 1fr));
    gap: 20px;
}

.kpn-node {
    transition: var(--ls-transition);
    cursor: pointer;
}

.kpn-node:hover {
    transform: translateY(-4px);
    box-shadow: var(--ls-shadow-lg);
    border-color: var(--ls-primary);
}

.kpn-node-header {
    display: flex;
    align-items: start;
    gap: 12px;
    margin-bottom: 12px;
}

.kpn-node-icon {
    font-size: 1.8rem;
    flex-shrink: 0;
}

.kpn-node-info {
    flex: 1;
    min-width: 0;
}

.kpn-node-name {
    margin: 0 0 4px 0;
    font-size: 1.1rem;
    font-weight: 700;
    color: var(--ls-text-primary);
    word-break: break-word;
}

.kpn-node-type {
    font-size: 0.85rem;
    color: var(--ls-text-secondary);
    background: var(--ls-bg-secondary);
    padding: 2px 8px;
    border-radius: 4px;
}

.kpn-node-description {
    margin: 12px 0;
    font-size: 0.95rem;
    color: var(--ls-text-secondary);
    line-height: 1.6;
}

.kpn-node-meta {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 12px 0;
}

.kpn-badge {
    font-size: 0.75rem;
    padding: 4px 10px;
    border-radius: 99px;
    background: var(--ls-bg-secondary);
    color: var(--ls-text-secondary);
    font-weight: 500;
}

.kpn-badge-level {
    background: var(--ls-primary-light);
    color: var(--ls-primary);
}

.kpn-badge-difficulty {
    background: var(--ls-accent);
    color: white;
}

.kpn-prerequisites {
    margin: 16px 0;
    padding: 12px;
    background: var(--ls-bg-secondary);
    border-radius: var(--ls-radius-md);
    border-left: 3px solid var(--ls-primary);
}

.kpn-prerequisites strong {
    display: block;
    margin-bottom: 8px;
    font-size: 0.9rem;
    color: var(--ls-text-primary);
}

.kpn-tags {
    display: flex;
    flex-wrap: wrap;
    gap: 6px;
}

.kpn-tag {
    font-size: 0.8rem;
    padding: 4px 10px;
    background: var(--ls-bg-primary);
    border: 1px solid var(--ls-border-color);
    border-radius: 99px;
    color: var(--ls-text-secondary);
}

.kpn-node-action {
    width: 100%;
    margin-top: 12px;
    justify-content: center;
}

/* 响应式设计 */
@media (max-width: 768px) {
    .kpn-nodes-grid {
        grid-template-columns: 1fr;
    }

    .kpn-level-title {
        font-size: 1.3rem;
    }
}