body { font-family: system-ui, sans-serif; margin: 2rem; }
#controls { display: block; }
.ctrl-row {
    display: flex;
    flex-wrap: wrap;
    gap: 0.5rem 0.75rem;
    align-items: center;
}
/* Add spacing between rows */
.ctrl-row + .ctrl-row {
    margin-top: 0.75rem;
}
/* Center the message row and give it space */
.row-3 {
    justify-content: flex-start;
    min-height: 1.5rem;
}
#status {
    font-style: italic;
}
.grid {
    display: inline-grid;
    margin-top: 1rem;
    border: 2px solid #444;
    grid-auto-rows: 2.2rem;
    overflow: hidden;  /* This clips any content that extends beyond the border */
}
/* Wrapper scrolls when content is larger than the viewport */
#gridWrap {
    max-width: 100%;
    max-height: calc(100vh - 240px);  /* leaves room for controls/status/nav */
    overflow: auto;                   /* both axes */
}
/* Grab-to-pan UX */
.pannable { cursor: grab; }
.pannable.grabbing { cursor: grabbing; }
.cell {
    width: 2.2rem; 
    height: 2.2rem;
    text-align: center; 
    font-size: 1rem; 
    line-height: 2.2rem;
    border: 1px solid #ccc;
    box-sizing: border-box;
}
.cell input { width: 100%; height: 100%; border: none; text-align: center; }
.wall  { background: #000; color: #000; }  /* black wall */
.isle  { background: #fff; }               /* island */
.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #444;
    border-radius: 50%;
    width: 28px; height: 28px;
    animation: spin 1s linear infinite;
    margin: 1rem auto;
}
@keyframes spin { 100% { transform: rotate(360deg); } }
.hidden { display: none; }
#status { margin-left: 1rem; font-style: italic; }
#prevBtn, #nextBtn { margin-left: 0.5rem; }

#navBar {
    margin-top: 0.5rem;
    display: flex;
    align-items: center;
    gap: 0.4rem;
    font-size: 0.95rem;
}
#navBar .hint { margin-left: 0.8rem; font-style: italic; opacity: 0.8; }
#stepCounter { min-width: 5.5rem; text-align: center; }

#navBar.hidden {           /* higher specificity than #navBar alone   */
    display: none !important;
}

.navbtn {
    width: 2.2rem;
    height: 2.2rem;
    padding: 0;
    display: inline-flex;      /* centre the glyph inside the square  */
    align-items: center;
    justify-content: center;
    line-height: 1;            /* ignore font’s default line-height   */
    text-align: center;
    font-size: 1rem;
    cursor: pointer;
}