* {
    box-sizing: border-box;
}

body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 24px;
    background: #f7f7f7;
    color: #1f1f1f;
}

.container {
    max-width: 960px;
    margin: 0 auto;
    background: #ffffff;
    padding: 24px;
    border-radius: 8px;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.08);
}

h1,
h2 {
    margin-top: 0;
}

.diff-form {
    display: grid;
    gap: 16px;
    margin-bottom: 24px;
}

.field {
    display: flex;
    flex-direction: column;
    gap: 8px;
    font-weight: 600;
}

textarea {
    width: 100%;
    padding: 12px;
    font-size: 14px;
    border: 1px solid #cfcfcf;
    border-radius: 6px;
    resize: vertical;
}

button {
    align-self: flex-start;
    padding: 10px 20px;
    background: #2f6fed;
    color: #ffffff;
    border: none;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
}

button:hover {
    background: #285fcb;
}

.diff-output {
    border-top: 1px solid #e2e2e2;
    padding-top: 16px;
}

.diff-result {
    display: flex;
    flex-wrap: wrap;
    gap: 6px 8px;
    line-height: 1.6;
}

.diff-result span {
    padding: 2px 6px;
    border-radius: 4px;
}

.diff-added {
    background: #d6f5d6;
}

.diff-changed {
    background: #fff3b0;
    cursor: pointer;
}

.diff-removed {
    background: #f8d7da;
    text-decoration: line-through;
}

.diff-keep {
    background: transparent;
}