body {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
    background-color: #f5f5f5;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
}

.container {
    background-color: white;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.1);
    padding: 30px;
    width: 100%;
    max-width: 500px;
    text-align: center;
}

h1 {
    color: #333;
    margin-bottom: 20px;
}

.form-group {
    margin-bottom: 20px;
}

input {
    width: 100%;
    padding: 12px;
    margin-bottom: 15px;
    border: 1px solid #ddd;
    border-radius: 5px;
    font-size: 16px;
    box-sizing: border-box;
}

button {
    background-color: #4CAF50;
    color: white;
    border: none;
    padding: 12px 20px;
    border-radius: 5px;
    cursor: pointer;
    font-size: 16px;
    width: 100%;
    transition: background-color 0.3s;
}

button:hover {
    background-color: #45a049;
}

button:disabled {
    background-color: #cccccc;
    cursor: not-allowed;
}

#timer {
    font-size: 28px;
    font-weight: bold;
    margin: 20px 0;
    color: #333;
}

#status {
    padding: 10px;
    border-radius: 5px;
    margin: 15px 0;
    font-weight: bold;
}

#counter {
    font-size: 14px;
    color: #666;
    margin-top: 10px;
}

.info {
    background-color: #e7f3fe;
    color: #2196F3;
}

.success {
    background-color: #ddffdd;
    color: #4CAF50;
}

.error {
    background-color: #ffdddd;
    color: #f44336;
}