body {
    font-family: 'Arial', sans-serif;
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    background-color: #282c34;
    color: #ffffff;
    text-align: center;
}

.container {
    background-color: #3a404a;
    padding: 40px 60px;
    border-radius: 15px;
    box-shadow: 0 10px 20px rgba(0, 0, 0, 0.3);
}

h1 {
    font-size: 2.5em;
    margin-bottom: 20px;
    color: #61dafb;
}

#mode-display {
    font-size: 1.5em;
    margin-bottom: 25px;
    color: #a0a8b3;
}

#timer-display {
    font-size: 8em;
    font-weight: bold;
    margin-bottom: 40px;
    letter-spacing: 5px;
    color: #ffffff;
}

.controls button {
    background-color: #61dafb;
    color: #282c34;
    border: none;
    padding: 15px 30px;
    margin: 0 10px;
    border-radius: 8px;
    font-size: 1.2em;
    cursor: pointer;
    transition: background-color 0.3s ease, transform 0.1s ease;
}

.controls button:hover:not(:disabled) {
    background-color: #4fa3d7;
    transform: translateY(-2px);
}

.controls button:active:not(:disabled) {
    transform: translateY(0);
}

.controls button:disabled {
    background-color: #555;
    color: #bbb;
    cursor: not-allowed;
}