body {
    background-color: #1e1e24;
    color: white;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    display: flex;
    flex-direction: column;
    align-items: center;
    padding: 40px 20px;
    margin: 0;
}

h2 {
    margin-bottom: 20px;
    border-bottom: 1px solid #444;
    padding-bottom: 10px;
    width: 100%;
    text-align: center;
}

.container {
    background-color: #495057;
    padding: 30px;
    border-radius: 12px;
    width: 100%;
    max-width: 350px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    text-align: center;
}

label {
    display: block;
    margin-bottom: 8px;
    font-weight: 600;
}

input, select, button {
    width: 100%;
    padding: 12px;
    margin-bottom: 20px;
    border-radius: 6px;
    border: none;
    font-size: 1rem;
    box-sizing: border-box;
}

button {
    background-color: #0dcaf0;
    color: white;
    font-weight: bold;
    text-transform: uppercase;
    cursor: pointer;
    transition: background-color 0.3s ease;
}

button:hover {
    background-color: #31d2f2;
}

.error-message {
    color: #ff8787;
    font-size: 0.85rem;
    font-weight: bold;
    min-height: 20px;
}

.chart-wrapper {
    background-color: #ffffff;
    margin-top: 40px;
    padding: 25px;
    border-radius: 12px;
    width: 90%;
    max-width: 700px;
}