.diff-label {
    display: block;
    margin-bottom: 6px;
    color: var(--text-secondary);
    font-size: 0.8rem;
    font-weight: 600;
}

.diff-source.text-output {
    display: block;
    width: 100%;
    min-height: 135px;
    max-height: 240px;
    resize: vertical;
    border: 1px solid var(--border);
    border-radius: 8px;
    font: 400 0.84rem/1.55 var(--font-family-sans);
    white-space: pre-wrap;
}

.diff-source.text-output:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.08);
}

.diff-options {
    display: grid;
    gap: 10px;
}

.diff-options h4 {
    margin-bottom: 0;
}

.diff-option {
    display: flex;
    align-items: center;
    gap: 9px;
    color: var(--text-secondary);
    font-size: 0.85rem;
    cursor: pointer;
}

.diff-option input {
    width: 16px;
    height: 16px;
    accent-color: var(--primary);
}

.diff-controls {
    margin: 0 0 10px;
}

.diff-secondary-actions {
    margin-bottom: 12px;
}

.diff-secondary-actions .calc-btn {
    padding: 9px 8px;
    font-size: 0.82rem;
}

.diff-status-error {
    color: #ef4444;
}

.footer-short-links {
    display: flex;
    align-items: center;
    gap: 16px;
    flex-wrap: wrap;
    margin-top: 10px;
    font-size: 0.85rem;
}

.footer-short-links a {
    color: var(--text-secondary);
    text-decoration: none;
    font-weight: 500;
    transition: color var(--motion-fast);
}

.footer-short-links a:hover {
    color: var(--primary);
}

.text-output.diff-result {
    min-height: 300px;
    font: 400 0.84rem/1.65 ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
    white-space: normal;
}

.diff-line {
    display: grid;
    grid-template-columns: 24px minmax(0, 1fr);
    gap: 6px;
    margin: 0 -8px;
    padding: 1px 8px;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
}

.diff-marker {
    user-select: none;
    text-align: center;
    font-weight: 700;
}

.diff-added {
    background: rgba(16, 185, 129, 0.12);
    color: #047857;
}

.diff-removed {
    background: rgba(239, 68, 68, 0.1);
    color: #b91c1c;
}

.diff-unchanged {
    color: var(--text-secondary);
}

.diff-summary {
    margin-bottom: 12px;
    padding-bottom: 10px;
    border-bottom: 1px solid var(--border);
    color: var(--text-muted);
    font: 500 0.75rem/1.5 var(--font-family-sans);
}

.diff-example {
    margin-top: 28px;
    padding: 24px;
    border: 1px solid var(--border);
    border-radius: 14px;
    background: var(--surface);
}

.diff-example h2 {
    margin: 0 0 8px;
    color: var(--text);
    font-size: 1.25rem;
}

.diff-example-intro {
    margin: 0 0 18px;
    color: var(--text-secondary);
    line-height: 1.6;
}

.diff-example-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 12px;
}

.diff-example-card {
    min-width: 0;
    padding: 16px;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: rgba(127, 127, 127, 0.04);
}

.diff-example-card h3 {
    margin: 0 0 10px;
    color: var(--text);
    font-size: 0.9rem;
}

.diff-example-source {
    margin: 0;
    color: var(--text-secondary);
    font: 400 0.85rem/1.7 ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
    white-space: pre-wrap;
    overflow-wrap: anywhere;
}

.diff-example-result-card {
    grid-column: 1 / -1;
}

.diff-example-output {
    display: grid;
    gap: 4px;
}

.diff-example-line {
    display: grid;
    grid-template-columns: 20px minmax(0, 1fr);
    gap: 8px;
    padding: 7px 10px;
    border-radius: 5px;
    font: 400 0.84rem/1.5 ui-monospace, SFMono-Regular, Consolas, "Liberation Mono", monospace;
    overflow-wrap: anywhere;
}

.diff-example-line .diff-marker {
    text-align: center;
}

@media (max-width: 1024px) {
    .calc-form {
        order: 1 !important;
    }

    .calc-results {
        order: 2 !important;
    }

    .diff-source.text-output {
        min-height: 110px;
    }
}

@media (max-width: 640px) {
    .diff-example {
        padding: 16px;
    }

    .diff-example-grid {
        grid-template-columns: 1fr;
    }

    .diff-example-result-card {
        grid-column: auto;
    }
}

@media (prefers-color-scheme: dark) {
    .diff-added {
        color: #6ee7b7;
    }

    .diff-removed {
        color: #fca5a5;
    }
}