:root {
    --bg-color: #f5f5f7;
    --card-bg-color: #ffffff;
    --text-primary: #1d1d1f;
    --text-secondary: #6e6e73;
    --border-color: rgba(0, 0, 0, 0.08);
    --input-border: #d2d2d7;
    --input-bg: #fff;
    --shadow-color: rgba(0, 0, 0, 0.08);
    --button-bg: #007aff;
    --button-hover: #0071e3;
    --pre-bg: #f5f5f7;
    --pre-border: #e5e5e5;
}


[data-theme="dark"] {
    --bg-color: #1c1c1e;
    --card-bg-color: #2c2c2e;
    --text-primary: #f5f5f7;
    --text-secondary: #8e8e93;
    --border-color: rgba(255, 255, 255, 0.1);
    --input-border: #4a4a4c;
    --input-bg: #3a3a3c;
    --shadow-color: rgba(0, 0, 0, 0.2);
    --button-bg: #0a84ff;
    --button-hover: #3395ff;
    --pre-bg: #1c1c1e;
    --pre-border: #3a3a3c;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", "Roboto", "Helvetica Neue", Arial, sans-serif;
    background-color: var(--bg-color);
    color: var(--text-primary);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    margin: 0;
    padding: 20px;
    box-sizing: border-box;
    transition: background-color 0.3s ease, color 0.3s ease;
}

.container {
    background-color: var(--card-bg-color);
    padding: 50px;
    border-radius: 16px;
    box-shadow: 0 10px 40px var(--shadow-color);
    border: 1px solid var(--border-color);
    max-width: 650px;
    width: 100%;
    text-align: center;
    transition: all 0.3s ease;
}

h1 {
    color: var(--text-primary);
    font-size: 2.2em; font-weight: 700; margin-bottom: 15px;
}
p {
    color: var(--text-secondary);
    font-size: 1.1em; line-height: 1.5; max-width: 450px; margin: 0 auto 35px auto;
}
input[type="text"] {
    width: calc(100% - 34px); padding: 16px; font-size: 1rem;
    border: 1px solid var(--input-border);
    background-color: var(--input-bg);
    color: var(--text-primary);
    border-radius: 12px; margin-bottom: 20px; transition: all 0.2s ease-in-out;
}
input[type="text"]:focus {
    outline: none; border-color: var(--button-bg); box-shadow: 0 0 0 4px rgba(0, 122, 255, 0.15);
}
button {
    background-color: var(--button-bg);
    color: white; border: none; padding: 16px 22px; font-size: 1rem; font-weight: 600;
    border-radius: 12px; cursor: pointer; width: 100%; transition: background-color 0.2s, transform 0.2s;
}
button:hover {
    background-color: var(--button-hover); transform: translateY(-2px);
}
#result-container {
    margin-top: 40px; text-align: left; border-top: 1px solid var(--border-color); padding-top: 30px;
}
#result-container h2 {
    color: var(--text-primary); font-size: 1.2em;
}
.code-block-wrapper { position: relative; margin-top: 15px; }
pre {
    background-color: var(--pre-bg); padding: 18px; border: 1px solid var(--pre-border);
    border-radius: 12px; white-space: pre-wrap; word-wrap: break-word;
    font-family: "SFMono-Regular", Consolas, "Liberation Mono", Menlo, monospace;
    font-size: 0.95em; color: var(--text-secondary);
}
#copy-button {
    position: absolute; top: 12px; right: 12px;
    background-color: #555; color: #fff; padding: 6px 12px;
    font-size: 0.8em; font-weight: 500; width: auto; border-radius: 8px;
    border: 1px solid #666;
}
#copy-button:hover { background-color: #666; }
.hidden { display: none; }



.theme-switch-container {
    position: absolute;
    top: 20px;
    right: 20px;
}
.theme-switch {
    display: inline-block;
    height: 24px;
    position: relative;
    width: 50px;
}
.theme-switch input {
    display:none;
}
.slider {
    background-color: #ccc;
    bottom: 0;
    cursor: pointer;
    left: 0;
    position: absolute;
    right: 0;
    top: 0;
    transition: .4s;
}
.slider:before {
    background-color: #fff;
    bottom: 2px;
    content: "";
    height: 20px;
    left: 2px;
    position: absolute;
    transition: .4s;
    width: 20px;
}
input:checked + .slider {
    background-color: #007aff;
}
input:checked + .slider:before {
    transform: translateX(26px);
}
.slider.round {
    border-radius: 34px;
}
.slider.round:before {
    border-radius: 50%;
}