body {
    margin: 0;
    padding: 0;
    font-family: Arial, sans-serif;
    background: #eef0f2;
}

.page {
    max-width: 900px;
    margin: auto;
    padding: 20px;
}

.card {
    background: #fff;
    padding: 20px;
    margin-bottom: 18px;
    border-radius: 12px;
    box-shadow: 0 2px 6px rgba(0,0,0,0.12);
}

h1 {
    margin: 0;
    font-size: 26px;
    color: #222;
}

.subtitle {
    margin-top: 5px;
    font-size: 14px;
    color: #666;
}

.form {
    display: flex;
    flex-direction: column;
    margin-top: 15px;
}

label {
    margin-top: 10px;
    font-weight: 600;
    color: #333;
}

input, select {
    padding: 8px;
    margin-top: 4px;
    border-radius: 6px;
    border: 1px solid #aaa;
    font-size: 14px;
}

button {
    margin-top: 16px;
    padding: 10px;
    background: #0074d9;
    color: white;
    border: none;
    border-radius: 7px;
    cursor: pointer;
    font-size: 15px;
}

button:hover {
    background: #005fb1;
}

pre {
    background: #f4f4f4;
    padding: 12px;
    border-radius: 6px;
    font-size: 13px;
    overflow-x: auto;
}

canvas {
    background: #ffffff;
    border-radius: 10px;
}

.chk {
    margin-top: 10px;
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 14px;
}