body {
    font-family: Arial, sans-serif;
    background: #f0f4f8;
    margin: 0;
    padding: 0;
}
.container {
    max-width: 350px;
    margin: 60px auto;
    background: #fff;
    border-radius: 10px;
    box-shadow: 0 2px 8px rgba(0,0,0,0.08);
    padding: 30px 20px;
    text-align: center;
}
h1 {
    color: #2d6cdf;
    margin-bottom: 20px;
}
input[type="number"] {
    width: 120px;
    padding: 8px;
    font-size: 1.1em;
    border: 1px solid #ccc;
    border-radius: 5px;
    margin-bottom: 18px;
}
.buttons {
    margin-bottom: 18px;
}
button {
    padding: 8px 18px;
    margin: 0 5px;
    font-size: 1em;
    border: none;
    border-radius: 5px;
    background: #2d6cdf;
    color: #fff;
    cursor: pointer;
    transition: background 0.2s;
}
button:hover {
    background: #1a4fa0;
}
#timerDisplay {
    font-size: 2.2em;
    margin-bottom: 10px;
    color: #333;
}
#message {
    font-size: 1.1em;
    color: #e74c3c;
    margin-top: 8px;
}