/* 1. Algemene Styling */
body {
    margin: 0;
    padding: 0;
    background-color: #0b0e14;
    overflow: hidden;
    
    /* DIT ZET ALLES IN HET MIDDEN */
    display: flex;
    justify-content: center; /* Horizontaal centreren */
    align-items: center;     /* Verticaal centreren */
    min-height: 100vh;       /* Zorg dat de body het hele scherm vult */
}

/* Zorg dat de canvas geen gekke marges meer heeft */
canvas {
    /* border: 4px solid rgba(255, 255, 255, 0.1); */
    box-shadow: 0 0 50px rgba(0,0,0,0.9);
    border-radius: 10px;
    display: block;  /* Haalt witruimte onder canvas weg */
}

/* 2. De Zijbalk (Dashboard) */
.buttons {
    position: absolute;
    top: 20px;
    left: 20px;
    z-index: 100;
    padding: 20px;
    background: rgba(255, 255, 255, 0.1); /* Half-transparant wit */
    backdrop-filter: blur(10px); /* HET GLASEFFECT */
    border: 1px solid rgba(255, 255, 255, 0.2);
    border-radius: 20px;
    box-shadow: 0 8px 32px 0 rgba(0, 0, 0, 0.8);
    display: flex;
    flex-direction: column;
    gap: 20px;
    max-height: 90vh;
    overflow-y: auto;
}

/* 3. Hoofdknoppen (Clear/Add) */
.control-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}

#button, #button2 {
    background: linear-gradient(135deg, #3498db, #2980b9);
    border: none;
    padding: 12px;
    font-weight: bold;
    text-transform: uppercase;
    letter-spacing: 1px;
    border-radius: 10px;
    transition: all 0.3s ease;
}

#button:hover, #button2:hover {
    background: linear-gradient(135deg, #2ecc71, #27ae60);
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(46, 204, 113, 0.4);
}

/* 4. De Planet Grid */
.planet-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    gap: 20px;
}

.planet-item {
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 8px;
}

.planet-item span {
    color: white;
    font-size: 12px;
    font-weight: bold;
    text-shadow: 1px 1px 3px rgba(0,0,0,0.8);
    font-family: 'Comic Sans MS', cursive; /* Jouw gewenste cartoon stijl */
}

/* 5. De Ronde Planeet Knoppen */
.planet-btn {
    width: 65px;
    height: 65px;
    border-radius: 50%;
    border: 3px solid rgba(255, 255, 255, 0.3);
    background-size: cover;
    background-position: center;
    cursor: pointer;
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    box-shadow: 0 0 10px rgba(0,0,0,0.5);
    background-color: #222;
}

.planet-btn:hover {
    transform: scale(1.2) rotate(10deg);
    border-color: #f1c40f;
    box-shadow: 0 0 20px rgba(241, 196, 15, 0.6);
}

/* 6. De Grote Tekst Bovenin */
.zwaartekrachtText {
    position: absolute;
    top: 20px;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    pointer-events: none; /* Je kunt erdoorheen klikken */
    width: 100%;
}

#zwaarte-kracht {
    color: white;
    font-size: 2.5rem;
    margin: 0;
    text-transform: uppercase;
    letter-spacing: 3px;
    text-shadow: 0 0 10px rgba(52, 152, 219, 0.8), 
                 0 0 20px rgba(0, 0, 0, 0.5);
    font-family: 'Arial Black', sans-serif;
}



/* Specifieke plaatjes per planeet */
#zon .planet-btn { background-image: url('img/sun_icon.png'); }
#maan .planet-btn { background-image: url('img/moon_icon.png'); }
#mercurius .planet-btn { background-image: url('img/mercury_icon.png'); }
#venus .planet-btn { background-image: url('img/venus_icon.png'); }
#aarde .planet-btn { background-image: url('img/earth_icon.png'); }
#mars .planet-btn { background-image: url('img/mars_icon.png'); }
#jupiter .planet-btn { background-image: url('img/jupiter_icon.png'); }
#saturnus .planet-btn { background-image: url('img/saturn_icon.png'); }
#uranus .planet-btn { background-image: url('img/uranus_icon.png'); }
#neptunus .planet-btn { background-image: url('img/neptune_icon.png'); }

.custom-gravity {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding: 15px;
    background: rgba(255, 255, 255, 0.05);
    border-radius: 15px;
    color: white;
    font-size: 14px;
    border: 1px solid rgba(255, 255, 255, 0.1);
}

#gravity-slider {
    cursor: pointer;
    accent-color: #3498db; /* Kleur van het schuifje */
}

#gravity-value {
    font-family: 'Courier New', Courier, monospace;
    font-weight: bold;
    color: #f1c40f;
    text-align: center;
}
/* Het volledige startscherm */
#start-screen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background: radial-gradient(circle, #1b2735 0%, #090a0f 100%); /* Diepe ruimte kleur */
    display: flex;
    justify-content: center;
    align-items: center;
    z-index: 2000; /* Hoger dan alles (ook je dashboard) */
    transition: opacity 0.8s ease; /* Voor een mooie fade-out */
}

/* De container met tekst en knop */
.start-content {
    text-align: center;
    background: rgba(255, 255, 255, 0.05);
    padding: 50px;
    border-radius: 30px;
    backdrop-filter: blur(15px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    box-shadow: 0 0 50px rgba(0, 0, 0, 0.5);
}

.start-content h1 {
    color: white;
    font-size: 4rem;
    margin-bottom: 10px;
    text-transform: uppercase;
    letter-spacing: 5px;
    text-shadow: 0 0 20px rgba(52, 152, 219, 0.8);
}

.start-content p {
    color: #bdc3c7;
    font-size: 1.2rem;
    margin-bottom: 30px;
}

/* De grote Startknop */
#start-btn {
    padding: 20px 50px;
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
    background: linear-gradient(135deg, #e67e22, #d35400);
    border: none;
    border-radius: 50px;
    cursor: pointer;
    box-shadow: 0 10px 20px rgba(0,0,0,0.3);
    transition: all 0.3s ease; 
    animation: flicker 3s infinite;
    transition: all 0.3s ease;
}


#start-btn:hover {
    transform: scale(1.1) translateY(-5px);
    background: linear-gradient(135deg, #f39c12, #e67e22);
    box-shadow: 0 15px 30px rgba(230, 126, 34, 0.4);
    animation: none; /* Stopt het flikkeren als je wilt klikken */
    transform: scale(1.1);
}

#back-btn {
    position: absolute;
    top: 20px;
    left: 20px;
    padding: 10px 20px;
    font-size: 14px;
    color: white;
    background: rgba(255, 255, 255, 0.1);
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: all 0.3s ease;
}

/* De 'flicker' animatie definitie */
@keyframes flicker {
  0%, 18%, 22%, 25%, 53%, 57%, 100% {
    opacity: 1;
    box-shadow: 0 0 20px rgba(230, 126, 34, 0.8), 0 0 40px rgba(230, 126, 34, 0.4);
    transform: scale(1);
  }
  20%, 24%, 55% {
    opacity: 0.7;
    box-shadow: none;
    transform: scale(0.99); /* Een heel klein beetje 'krimpen' bij het flikkeren */
  }
}

.corner-btn {
    position: fixed;
    top: 20px;
    right: 20px;
    z-index: 1000; /* Zorgt dat hij boven het canvas en de zijbalk zweeft */
    
    background: rgba(255, 255, 255, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: white;
    padding: 10px 20px;
    border-radius: 12px;
    font-weight: bold;
    cursor: pointer;
    transition: all 0.3s ease;
    text-transform: uppercase;
    letter-spacing: 1px;
    font-size: 13px;
}

.corner-btn:hover {
    background: rgba(231, 76, 60, 0.2); /* Een subtiele rode gloed bij hover (gevaar/stop) */
    border-color: #e74c3c;
    transform: translateY(2px); /* Een kleine klik-beweging naar beneden */
    box-shadow: 0 0 15px rgba(231, 76, 60, 0.4);
}