body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    transition: background-color 0.3s, color 0.3s;
}
body.dark-mode {
    background-color: #121212;
    color: #e0e0e0;
}
.container {
    max-width: 800px;
    margin: 0 auto;
    padding: 20px;
    background-color: #1e1e1e;
    box-shadow: 0 0 10px rgba(255,255,255,0.1);
    border-radius: 5px;
}
h1 {
    text-align: center;
    color: #bb86fc;
}
.introduction {
    background-color: #2e2e2e;
    border-radius: 5px;
    padding: 20px;
    margin-bottom: 20px;
}
.introduction h2 {
    color: #03dac6;
    font-size: 1.2em;
    margin-top: 15px;
    margin-bottom: 10px;
}
.introduction ul {
    list-style-type: disc;
    padding-left: 20px;
}
.introduction li {
    margin-bottom: 5px;
}
.input-area {
    display: flex;
    justify-content: center;
    margin-bottom: 20px;
    flex-wrap: wrap;
}
input[type="text"] {
    width: 300px;
    padding: 10px;
    font-size: 16px;
    border: 1px solid #bb86fc;
    border-radius: 4px;
    margin: 5px;
    background-color: #2e2e2e;
    color: #e0e0e0;
}
button {
    padding: 10px 20px;
    font-size: 16px;
    background-color: #bb86fc;
    color: #121212;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    margin: 5px;
    transition: background-color 0.3s;
}
button:hover {
    background-color: #03dac6;
}
.charts {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
#complexFunctionPlot {
    width: 100%;
    height: 400px;
}
#magnitudeChart {
    width: 100%;
    height: 200px;
}
#loadingMessage {
    background-color: #3e3e3e;
    color: #e0e0e0;
    padding: 10px;
    border-radius: 5px;
    text-align: center;
    margin: 10px 0;
    font-weight: bold;
}
.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #bb86fc;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 1s linear infinite;
    margin: 0 auto 10px;
}
@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}
#stopButton {
    background-color: #cf6679;
}
#stopButton:hover {
    background-color: #a00000;
}