/*
 * Optional "back to hub" link that any app can include.
 * Everything is namespaced under .hub-nav so it can't collide with app styles.
 */
.hub-nav {
    position: fixed;
    top: 12px;
    left: 12px;
    z-index: 1000;
    display: inline-flex;
    align-items: center;
    gap: 6px;
    padding: 8px 14px;
    border-radius: 999px;
    background: rgba(255, 255, 255, .9);
    border: 1px solid rgba(0, 0, 0, .08);
    box-shadow: 0 2px 8px rgba(0, 0, 0, .06);
    color: #1f2937;
    font: 600 .85rem/1 Inter, system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    text-decoration: none;
    backdrop-filter: blur(6px);
    transition: transform .15s, box-shadow .15s;
}

.hub-nav:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, .1);
}

/* Dark mode: shared/theme.js sets data-theme="dark" (chosen, or Auto on a dark device) */
:root[data-theme="dark"] .hub-nav {
    background: rgba(36, 38, 46, .9);
    border-color: rgba(255, 255, 255, .12);
    box-shadow: 0 2px 8px rgba(0, 0, 0, .4);
    color: #e7e9ee;
}