:root {
    --bg-color: #2c3e50;
    --panel-bg: #34495e;
    --text-color: #ecf0f1;
    --primary-color: #3498db;
    --secondary-color: #2ecc71;
    --border-color: #2c3e50;
    --input-bg: #2c3e50;
}

*, *::before, *::after {
    box-sizing: border-box;
}

body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    margin: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-size: 16px;
}

.main-container {
    display: flex;
    flex-direction: column;
    gap: 20px;
    padding: 15px;
    width: 100%;
}

.controls-panel {
    background-color: var(--panel-bg);
    padding: 20px;
    border-radius: 12px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
}

.maze-container {
    display: flex;
    align-items: center;
    justify-content: center;
    width: 100%;
}

canvas {
    border-radius: 8px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.2);
    max-width: 100%;
    height: auto;
}

h1 {
    text-align: center;
    color: var(--primary-color);
    margin-top: 0;
    margin-bottom: 25px;
    font-size: 1.8em;
}

fieldset {
    border: 1px solid var(--border-color);
    border-radius: 8px;
    margin-bottom: 20px;
    padding: 15px;
}

legend {
    color: var(--primary-color);
    font-weight: bold;
    padding: 0 10px;
}

.control-group {
    margin-bottom: 15px;
}

.control-group label {
    display: block;
    margin-bottom: 8px;
    font-size: 1em;
}

input[type="range"], select, input[type="text"] {
    width: 100%;
    background-color: var(--input-bg);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    border-radius: 5px;
    padding: 10px;
    font-size: 1em;
}

select {
    padding: 12px 10px;
}

.button-group {
    display: flex;
    gap: 10px;
}

button {
    flex-grow: 1;
    background-color: var(--primary-color);
    color: white;
    font-weight: bold;
    border: none;
    padding: 15px 10px;
    border-radius: 5px;
    font-size: 1em;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.1s ease;
}

button#solveBtn {
    background-color: var(--secondary-color);
}

button:hover {
    opacity: 0.9;
}

button:active {
    transform: scale(0.98);
}

@media (min-width: 900px) {
    .main-container {
        flex-direction: row;
        align-items: flex-start;
        padding: 2vw;
        gap: 30px;
    }

    .controls-panel {
        flex: 1;
        max-width: 420px;
        min-width: 340px;
        position: sticky;
        top: 20px;
    }

    .maze-container {
        flex: 2;
    }

    h1 {
        font-size: 2em;
    }
}