body {
    font-family: Arial, sans-serif;
    width: 600px;
    margin: 0 auto;
    padding: 20px;
    background-color: #f5f5f5;
}
.calculator {
    background-color: white;
    padding: 30px;
    border-radius: 8px;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}
h1 {
    text-align: center;
    color: #333;
}
.input-group {
    margin-bottom: 15px;
}
label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: #555;
}
input[type="date"],
input[type="number"] {
    width: 100%;
    padding: 10px;
    border: 1px solid #ddd;
    border-radius: 4px;
    box-sizing: border-box;
}
button {
    width: 100%;
    padding: 12px;
    background-color: #4CAF50;
    color: white;
    border: none;
    border-radius: 4px;
    cursor: pointer;
    font-size: 16px;
}
button:hover {
    background-color: #45a049;
}
#result {
    margin-top: 20px;
    padding: 15px;
    background-color: #e7f3ff;
    border-left: 6px solid #2196F3;
    font-size: 18px;
    font-weight: bold;
    text-align: center;
    display: none; /* Скрыто до вычисления */
}
    .error {
    background-color: #ffebee;
    border-left-color: #f44336;
    color: #d32f2f;
}

.banner {
padding-top: 20px;
}