body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f0f4f8;
    color: #333;
    display: flex;
    flex-direction: column;
    align-items: center;
    margin: 0;
    padding: 20px;
}

.container {
    background-color: white;
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 10px 25px rgba(0,0,0,0.1);
    max-width: 800px;
    width: 100%;
    text-align: center;
}

h1 {
    color: #2c3e50;
    margin-bottom: 20px;
}

.controls {
    margin-bottom: 20px;
    padding: 15px;
    background-color: #eef2f7;
    border-radius: 10px;
    display: flex;
    align-items: center;
    justify-content: center;
    gap: 15px;
}

button {
    padding: 10px 20px;
    background-color: #3498db;
    color: white;
    border: none;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #2980b9;
}

input[type=range] {
    width: 200px;
}

#statusText {
    font-weight: bold;
    min-width: 150px;
    text-align: left;
}

.visualization {
    margin: 20px 0;
    border: 1px solid #eee;
    border-radius: 10px;
    background-color: #fafafa;
}

.explanation {
    display: flex;
    justify-content: space-around;
    margin-top: 20px;
    text-align: left;
}

.phase {
    width: 45%;
    padding: 15px;
    border-radius: 8px;
    transition: background-color 0.3s;
}

.phase h3 {
    margin-top: 0;
    color: #2c3e50;
    border-bottom: 2px solid #3498db;
    padding-bottom: 5px;
}

.phase ul {
    padding-left: 20px;
}

.phase li {
    margin-bottom: 5px;
}

/* Active state highlighting */
.active-phase {
    background-color: #e8f6f3;
    border: 2px solid #1abc9c;
}