body {
    display: flex;
    flex-direction: column;
    justify-content: center;
    align-items: center;
    height: 100vh;
    font-family: Arial, sans-serif;
    background-color: var(--background-color);
    color: var(--text-color);
    margin: 0;
}
.stopwatch {
    background-color: var(--foreground-color);
    padding: 20px;
    border-radius: 10px;
    box-shadow: 0 0 10px rgba(0, 0, 0, 0.1);
    text-align: center;
}
.time-container {
    display: flex;
    justify-content: center;
    align-items: center;
}
.time {
    font-size: 2em;
    margin: 10px 5px 0 5px;
}
.labels {
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 0.8em;
    color: var(--label-color);
}
.label {
    margin: 0 15px;
}
.buttons {
    margin-top: 20px;
    display: flex;
    justify-content: center;
}
.buttons button {
    margin: 5px;
    padding: 10px;
    font-size: 1em;
    border: none;
    border-radius: 50%;
    cursor: pointer;
    display: flex;
    justify-content: center;
    align-items: center;
    width: 50px;
    height: 50px;
    background-color: var(--button-background-color);
    color: white;
    position: relative;
}
.buttons button:hover {
    opacity: 0.9;
}
.buttons button svg {
    width: 24px;
    height: 24px;
}
.tooltip {
    position: absolute;
    top: -30px;
    background-color: var(--tooltip-background-color);
    color: var(--tooltip-text-color);
    padding: 5px;
    border-radius: 5px;
    font-size: 0.8em;
    opacity: 0;
    transition: opacity 0.3s;
}
.buttons button:hover .tooltip {
    opacity: 1;
}
.theme-switch {
    position: absolute;
    top: 20px;
    right: 20px;
}
.theme-switch input {
    display: none;
}
.theme-switch label {
    cursor: pointer;
    text-indent: -9999px;
    width: 52px;
    height: 27px;
    background: var(--switch-background);
    display: block;
    border-radius: 100px;
    position: relative;
}
.theme-switch label:after {
    content: '';
    position: absolute;
    top: 2px;
    left: 2px;
    width: 23px;
    height: 23px;
    background: var(--switch-knob);
    border-radius: 90px;
    transition: 0.3s;
}
.theme-switch input:checked + label {
    background: var(--switch-background-checked);
}
.theme-switch input:checked + label:after {
    left: calc(100% - 2px);
    transform: translateX(-100%);
}
.dark {
    --background-color: #121212;
    --foreground-color: #1e1e1e;
    --text-color: #e0e0e0;
    --label-color: #a0a0a0;
    --button-background-color: #333;
    --tooltip-background-color: #333;
    --tooltip-text-color: #e0e0e0;
    --switch-background: #333;
    --switch-knob: #fff;
    --switch-background-checked: #555;
}
.light {
    --background-color: #f0f0f0;
    --foreground-color: #fff;
    --text-color: #121212;
    --label-color: #666;
    --button-background-color: #4CAF50;
    --tooltip-background-color: #333;
    --tooltip-text-color: #fff;
    --switch-background: #ccc;
    --switch-knob: #fff;
    --switch-background-checked: #4CAF50;
}