body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Helvetica, Arial, sans-serif;
    line-height: 1.6;
    background: #fafafa;
    color: #333;
}

main {
    max-width: 900px;
    margin: 40px auto;
    padding: 0 20px;
}

h1, h2 {
    font-weight: 600;
}

hr {
    margin: 30px 0;
    border: 0;
    border-top: 1px solid #ddd;
}

/* ------------------------------------------------------------
   SIDE-BY-SIDE LAYOUT — ALWAYS EQUAL WIDTH
------------------------------------------------------------ */
#plot-row {
    display: flex;
    flex-direction: row;
    gap: 20px;
    justify-content: space-between;
    align-items: flex-start;
}

.plot-column {
    flex: 1 1 0;     /* 50% width each, enforced */
    display: flex;
    flex-direction: column;
    gap: 15px;
}

/* ------------------------------------------------------------
   PLOTS
------------------------------------------------------------ */
.plot {
    width: 100%;
    height: 500px;
    border: 1px solid #ddd;
    background: #fff;
}

/* ------------------------------------------------------------
   UMAP Control Panel
------------------------------------------------------------ */
#umap-panel {
    border: 1px solid #ccc;
    background: #ffffff;
    padding: 15px;
    border-radius: 6px;
    box-shadow: 0px 1px 2px rgba(0,0,0,0.05);
}

#umap-panel h3 {
    margin: 0 0 10px 0;
    font-weight: 600;
}

.control-block {
    margin-bottom: 18px;
}

input[type="range"] {
    width: 100%;
    margin-top: 6px;
}

.value-label {
    font-weight: bold;
    color: #555;
    padding-left: 6px;
}