:root {
    --bg-color: #f9f9f9;
    --container-bg: #ffffff;
    --text-color: #333333;
    --label-color: #555555;
    --border-color: #dddddd;
    --button-bg: #007bff;
    --button-hover: #0056b3;
    --shadow: 0 4px 6px rgba(0,0,0,0.1);
}

[data-theme="dark"] {
    --bg-color: #121212;
    --container-bg: #1e1e1e;
    --text-color: #e0e0e0;
    --label-color: #bbbbbb;
    --border-color: #333333;
    --button-bg: #3700b3;
    --button-hover: #6200ee;
    --shadow: 0 4px 6px rgba(0,0,0,0.5);
}

body {
    font-family: 'Pretendard', sans-serif;
    padding: 20px;
    background-color: var(--bg-color);
    color: var(--text-color);
    transition: background-color 0.3s, color 0.3s;
}

.form-container {
    max-width: 500px;
    margin: 40px auto;
    background: var(--container-bg);
    padding: 30px;
    border-radius: 12px;
    box-shadow: var(--shadow);
    transition: background-color 0.3s, box-shadow 0.3s;
}

h2 {
    margin-top: 0;
    color: var(--text-color);
    text-align: center;
}

.form-group {
    margin-bottom: 15px;
}

label {
    display: block;
    margin-bottom: 5px;
    font-weight: bold;
    color: var(--label-color);
}

input[type="text"], input[type="email"], textarea, select {
    width: 100%;
    padding: 10px;
    border: 1px solid var(--border-color);
    border-radius: 6px;
    box-sizing: border-box;
    font-size: 14px;
    background-color: var(--container-bg);
    color: var(--text-color);
    transition: border-color 0.3s, background-color 0.3s, color 0.3s;
}

textarea {
    height: 120px;
    resize: vertical;
}

button {
    width: 100%;
    padding: 12px;
    background-color: var(--button-bg);
    color: white;
    border: none;
    border-radius: 6px;
    font-size: 16px;
    font-weight: bold;
    cursor: pointer;
    transition: background 0.3s;
}

button:hover {
    background-color: var(--button-hover);
}

.theme-toggle {
    position: fixed;
    top: 20px;
    right: 20px;
    padding: 10px 15px;
    background-color: var(--container-bg);
    color: var(--text-color);
    border: 1px solid var(--border-color);
    border-radius: 20px;
    cursor: pointer;
    box-shadow: var(--shadow);
    font-weight: bold;
}