:root {
    --color-red: #E74C3C;
    --color-blue: #3498DB;
    --color-green: #2ECC71;
    --color-yellow: #F1C40F;
    --bg-color: #F8F8FF;
    --text-color: #333;
    --line-color: black;
    --gradient-start: white;
    --gradient-end: #F8E0E0; 
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}

body {
    font-family: 'Roboto', sans-serif;   
    background: linear-gradient(to bottom, var(--gradient-start) 0%, var(--gradient-end) 100%); 
    background-color: var(--bg-color); 
    color: var(--text-color);
    display: flex;
    justify-content: center; /* Menengahkan secara horizontal */
    align-items: center; /* Menengahkan secara vertikal */
    min-height: 100vh;
    padding: 10px;
}

.container {
    background: white;
    padding: 15px;
    border-radius: 15px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
    max-width: 95%;
    width: 600px;
    text-align: center;
    margin: auto; 
}

h1 {
    color: #027b41;
    margin-bottom: 5px;
    font-size: 1.5em;
}

h4 {
    color: #9B59B6;
    margin-bottom: 1px;
    font-size: 1.0em;
}

p {
    color: #9B59B6;
    margin-bottom: 10px;
    font-size: 0.9em;
}

.score-display {
    font-size: 1em;
    font-weight: bold;
    color: var(--text-color);
    margin-bottom: 15px;
}

.grid-container {
    display: grid;
    grid-template-columns: repeat(4, 1fr);
    gap: 8px;
    margin-bottom: 15px;
}

.grid-item {
    width: 100%;
    padding-bottom: 100%;
    position: relative;
    border-radius: 8px;
    overflow: hidden;
    cursor: crosshair;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.box-color-red { background-color: var(--color-red); }
.box-color-blue { background-color: var(--color-blue); }
.box-color-green { background-color: var(--color-green); }
.box-color-yellow { background-color: var(--color-yellow); }


.grid-item.locked {
    opacity: 0.7;
    cursor: default;
}


.example-line {
    position: absolute;
    height: 4px;
    background-color: var(--line-color);
    transform-origin: 0 0;
    z-index: 1;
}


.user-line {
    position: absolute;
    background-color: black;
    height: 4px;
    transform-origin: 0 0;
    z-index: 2;
    transition: background-color 0.1s;
}


.user-line.wrong {
    background-color: var(--color-red) !important;
}




/* Horizontal */
.horizontal, .h {
    width: 100%;
    top: 50%;
    left: 0;
    margin-top: -2px;
}
/* Vertikal */
.vertical, .v {
    height: 100%;
    width: 4px;
    top: 0;
    left: 50%;
    margin-left: -2px;
}
/* Diagonal Kanan (DR) - Top-Left to Bottom-Right, 45 deg */
.diagonal-right, .dr {
    width: 141.4%;
    top: 0;
    left: 0;
    transform: rotate(45deg) translateY(4px); 
}
/* Diagonal Kiri (DL) - Bottom-Left to Top-Right, -45 deg */
.diagonal-left, .dl {
    width: 141.4%;
    top: 100%;
    left: 0;
    transform: rotate(-45deg) translateY(-4px); 
    transform-origin: 0 0;
}


.controls {
    margin-top: 15px;
}

#resetButton {
    padding: 10px 20px;
    font-size: 16px;
    background-color: var(--color-blue);
    color: white;
    border: none;
    border-radius: 20px;
    cursor: pointer;
    transition: background-color 0.3s;
    width: 100%;
    max-width: 250px;
}

#resetButton:hover {
    background-color: #2980B9;
}

.instruction-mobile {
    margin-top: 10px;
    font-size: 0.85em;
    color: #7f8c8d;
}