body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #3498db;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    height: 100vh;
    color: #ecf0f1;
}

#app {
    background-color: #2c3e50;
    padding: 20px;
    border-radius: 8px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    text-align: center;
}

h1 {
    margin-bottom: 20px;
    color: #e74c3c;
}

div {
    margin-bottom: 20px;
}

label {
    display: block;
    margin-bottom: 5px;
    color: #bdc3c7;
}

input {
    width: 100%;
    padding: 8px;
    margin-bottom: 10px;
    box-sizing: border-box;
}

button {
    padding: 10px;
    background-color: #3498db;
    color: #fff;
    border: none;
    border-radius: 4px;
    cursor: pointer;
}

#timer {
    font-size: 24px;
    font-weight: bold;
}