body {
    background: radial-gradient(circle at center, #0b0f1a 0%, #000000 100%);
    color: #e6f0ff;
    margin: 0;
    overflow: hidden;
    font-family: "Segoe UI", Roboto, Arial, sans-serif;
}

/* PANELS (boîtes UI) */
.panel {
    position: absolute;
    background: rgba(25, 25, 112, 0.55);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(100, 150, 255, 0.3);
    border-radius: 12px;
    padding: 1em;
    box-shadow: 0 0 20px rgba(0, 100, 255, 0.2);
}

/* Titres */
.panel h1 {
    font-size: 1.2em;
    margin-bottom: 0.5em;
    border-bottom: 1px solid rgba(255,255,255,0.2);
    padding-bottom: 0.3em;
}

/* Texte */
.panel p {
    margin: 0.3em 0;
    font-size: 0.9em;
    opacity: 0.9;
}

/* Boutons */
.button {
    display: block;
    width: 100%;
    margin: 0.3em 0;
    padding: 0.5em;
    border-radius: 8px;
    border: 1px solid rgba(100, 150, 255, 0.4);
    background: rgba(0, 0, 50, 0.6);
    color: #e6f0ff;
    cursor: pointer;
    transition: all 0.2s ease;
}

/* Hover effet */
.button:hover {
    background: rgba(50, 100, 255, 0.4);
    box-shadow: 0 0 10px rgba(100, 150, 255, 0.6);
    transform: translateY(-1px);
}

/* Click effet */
.button:active {
    transform: scale(0.97);
}

/* Inputs */
input[type="range"] {
    width: 100%;
    margin-top: 0.5em;
}

input[type="number"] {
    width: 100%;
    margin-top: 0.5em;
    padding: 0.3em;
    border-radius: 6px;
    border: none;
    background: rgba(0,0,0,0.6);
    color: white;
}

/* Canvas */
canvas {
    display: block;
}

/* Positions spécifiques */
#left-panel {
    left: 1em;
    top: 1em;
}

#selected-astronomical-object-div {
    bottom: 1em;
    left: 50%;
    transform: translateX(-50%);
}

#options {
    right: 1em;
    top: 1em;
}