body {
    font-family: Arial, sans-serif;
    background-color: #f5f5f5;
    color: #333;
}

.container {
    max-width: 600px;
    margin: 0 auto;
    padding: 20px;
}

h1 {
    text-align: center;
}

.timer {
    text-align: center;
    margin-bottom: 20px;
}

#timer-display {
    font-size: 48px;
    font-weight: bold;
}

#progress-bar {
    height: 10px;
    background-color: #ccc;
}

.controls {
    text-align: center;
    margin-bottom: 20px;
}

.session-indicator {
    text-align: center;
    margin-bottom: 20px;
}

.settings {
    background-color: #fff;
    padding: 20px;
    border-radius: 5px;
}

.settings h2 {
    margin-top: 0;
}

.duration {
    margin-bottom: 10px;
}

.duration label {
    display: inline-block;
    width: 150px;
}

.duration input {
    width: 50px;
}

.dark-mode {
    margin-top: 20px;
}

.dark-mode label {
    display: inline-block;
    width: 150px;
}