:root {
    --bg-color: #ffffff;
    --text-color: #000000;
    --input-bg: #f0f0f0;
    --button-bg: #007bff;
    --button-text: #ffffff;
    --border-color: #ccc;
}
[data-theme="dark"] {
    --bg-color: #121212;
    --text-color: #ffffff;
    --input-bg: #333333;
    --button-bg: #0056b3;
    --border-color: #555;
}
body {
    font-family: Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
    padding: 20px;
    max-width: 800px;
    margin: auto;
}
h1 {
    text-align: center;
}
.container {
    display: flex;
    flex-direction: column;
    gap: 20px;
}
.input-group {
    display: flex;
    flex-direction: column;
    gap: 10px;
}
label {
    font-weight: bold;
}
input, select, button {
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 5px;
    background-color: var(--input-bg);
    color: var(--text-color);
}
button {
    background-color: var(--button-bg);
    color: var(--button-text);
    cursor: pointer;
    transition: background-color 0.3s;
}
button:hover {
    opacity: 0.8;
}
.preview {
    background-color: var(--input-bg);
    padding: 15px;
    border-radius: 5px;
    border: 1px solid var(--border-color);
}
.format-group {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
    gap: 15px;
}
.format-item {
    background-color: var(--input-bg);
    padding: 10px;
    border-radius: 5px;
    border: 1px solid var(--border-color);
    text-align: center;
    display: flex;
    flex-direction: column;
    justify-content: space-between;
    min-height: 120px;
}
.format-item button {
    width: 100%;
    margin-top: auto;
}
.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
}
.error {
    color: red;
    font-size: 0.9em;
}
.toast {
    position: fixed;
    top: 20px;
    right: 20px;
    background-color: #4CAF50;
    color: white;
    padding: 15px;
    border-radius: 5px;
    z-index: 1000;
    opacity: 0;
    transition: opacity 0.3s;
}
.toast.show {
    opacity: 1;
}
@media (max-width: 600px) {
    .format-group {
        grid-template-columns: 1fr;
    }
}
.tooltip {
    position: relative;
    display: inline-block;
}
.tooltip .tooltiptext {
    visibility: hidden;
    width: 200px;
    background-color: black;
    color: #fff;
    text-align: center;
    border-radius: 6px;
    padding: 5px;
    position: absolute;
    z-index: 1;
    bottom: 125%;
    left: 50%;
    margin-left: -100px;
    opacity: 0;
    transition: opacity 0.3s;
}
.tooltip:hover .tooltiptext {
    visibility: visible;
    opacity: 1;
}
.changelog {
    position: fixed;
    top: 20px;
    left: 20px;
    background-color: var(--input-bg);
    color: var(--text-color);
    padding: 10px;
    border-radius: 5px;
    border: 1px solid var(--border-color);
    max-width: 200px;
    font-size: 0.9em;
}
.changelog h3 {
    margin: 0 0 10px 0;
    font-size: 1em;
}
.changelog ul {
    margin: 0;
    padding-left: 20px;
}
h1 a {
    color: var(--text-color);
    text-decoration: none;
}