:root {
    --arch-bg: #ffffff;
    --arch-text: #222;
    --arch-muted: #666;
    --arch-accent: #067f04;
    --arch-border: #d0d0d0;
    --arch-radius: 8px;
    --arch-hover: #f3f7f3;
}

body {
    font-family: Arial, Helvetica, sans-serif;
}

button {
    margin-top: 0.5rem;
    width: 150px;
    height: 30px;
    border-radius: 8px;
}

/* Layout containers */
#architecture-tree {
    padding: 1rem;
    max-width: 600px;
}

#architecture-details {
    padding: 1rem;
    border-left: 1px solid var(--arch-border);
    min-width: 280px;
    background: #fafafa;
}

/* Tree nodes */
.arch-node {
    margin: 0.25rem 0;
    position: relative;
}

/* Header (clickable part) */
.arch-node-header {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    cursor: pointer;
    padding: 0.25rem 0.4rem;
    border-radius: var(--arch-radius);
    color: var(--arch-text);
    font-weight: 600;
}

.arch-node-header.active {
    background: var(--arch-accent);
    color: white;
}

.arch-node-header:hover {
    background: var(--arch-hover);
    color: var(--arch-accent);
}

/* Arrow indicator */
.arch-node.has-children > .arch-node-header::before {
    content: "▶";
    font-size: 0.8em;
    transition: transform 0.15s ease;
    color: var(--arch-muted);
}

/* Open state (set via JS by toggling class) */
.arch-node.open > .arch-node-header::before {
    transform: rotate(90deg);
}

.arch-node.active-path > .arch-node-header {
    background: rgba(6, 127, 4, 0.15);
}

/* Children container */
.arch-children {
    margin-left: 1.2rem;
    padding-left: 0.5rem;
    border-left: 1px dashed var(--arch-border);
}

/* Detail panel content */
#architecture-details h3 {
    margin-top: 0;
    color: var(--arch-accent);
}

#architecture-details p {
    margin: 0.4rem 0;
    color: var(--arch-text);
    line-height: 1.4;
}

#architecture-details ul {
    margin: 0.5rem 0 0;
    padding-left: 1.2rem;
}

#architecture-details a {
    color: var(--arch-accent);
    text-decoration: none;
}

#architecture-details a:hover {
    text-decoration: underline;
}