.tool-header {
    display: flex;
    align-items: center;
    gap: 16px;
    margin-top: 24px;
}

.tool-layout {
    display: grid;
    grid-template-columns: 360px minmax(0, 1fr);
    gap: 24px;
    align-items: start;
}

.panel {
    background: var(--bg-card);
    border: 1px solid var(--border-color);
    border-radius: 16px;
    box-shadow: var(--shadow-sm);
}

.control-panel {
    position: sticky;
    top: 18px;
    padding: 22px;
    display: flex;
    flex-direction: column;
    gap: 18px;
}

.workspace-panel {
    padding: 22px;
    display: flex;
    flex-direction: column;
    gap: 18px;
    min-height: 760px;
}

.panel-header,
.workspace-header,
.badge-row,
.button-row {
    display: flex;
    align-items: flex-start;
    justify-content: space-between;
    gap: 12px;
    flex-wrap: wrap;
}

.panel-header p,
.workspace-header p,
.helper-text,
.notes-list,
.status-line {
    color: var(--text-secondary);
}

.panel-header h2,
.workspace-header h2,
.section-block h3 {
    margin-bottom: 4px;
}

.section-block {
    display: flex;
    flex-direction: column;
    gap: 12px;
    padding-top: 18px;
    border-top: 1px solid var(--border-color);
}

.section-block:first-of-type {
    border-top: none;
    padding-top: 0;
}

.section-block.compact {
    gap: 10px;
}

.advanced-panel summary {
    cursor: pointer;
    list-style: none;
    font-size: 1.02rem;
    font-weight: 600;
    color: var(--text-primary);
}

.advanced-panel summary::-webkit-details-marker {
    display: none;
}

.advanced-content {
    display: flex;
    flex-direction: column;
    gap: 14px;
    padding-top: 6px;
}

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

.input-line {
    display: flex;
    flex-direction: column;
    gap: 6px;
}

.input-line span,
.stat-label {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.76rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
    color: var(--text-secondary);
}

.input-line input,
.input-line select,
.input-line textarea {
    width: 100%;
    padding: 10px 12px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font: 500 0.92rem 'JetBrains Mono', monospace;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.input-line input:focus,
.input-line select:focus,
.input-line textarea:focus {
    border-color: var(--accent-engineering);
    box-shadow: 0 0 0 3px var(--accent-engineering-dim);
}

.input-line textarea {
    min-height: 76px;
    resize: vertical;
    line-height: 1.45;
}

.textarea-line {
    grid-column: span 1;
}

.tool-btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 0 14px;
    border-radius: 10px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-primary);
    font: 600 0.82rem 'JetBrains Mono', monospace;
    cursor: pointer;
    transition: border-color 0.2s ease, transform 0.2s ease;
}

.tool-btn:hover {
    border-color: var(--accent-engineering);
    transform: translateY(-1px);
}

.tool-btn.danger:hover {
    border-color: var(--accent-error);
}

.status-line {
    padding: 11px 12px;
    border-radius: 12px;
    background: color-mix(in srgb, var(--accent-engineering) 10%, transparent);
    border: 1px solid color-mix(in srgb, var(--accent-engineering) 25%, var(--border-color));
    font-size: 0.92rem;
}

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

.stat-card {
    padding: 14px;
    border-radius: 14px;
    border: 1px solid var(--border-color);
    background: linear-gradient(180deg, color-mix(in srgb, var(--bg-secondary) 88%, white 12%), var(--bg-secondary));
}

.stat-value {
    display: block;
    margin-top: 8px;
    font: 700 0.98rem 'JetBrains Mono', monospace;
    color: var(--text-primary);
}

.notes-list {
    padding-left: 18px;
    display: flex;
    flex-direction: column;
    gap: 8px;
}

.check-line {
    display: flex;
    align-items: center;
    gap: 10px;
    color: var(--text-secondary);
    font-size: 0.92rem;
}

.check-line input {
    accent-color: var(--accent-engineering);
}

.scale-toggle {
    padding: 8px 0 2px;
}

.advanced-fieldset {
    padding: 0;
    margin: 0;
    border: none;
    min-width: 0;
}

.advanced-fieldset:disabled {
    opacity: 0.55;
}

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

.advanced-opacity-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.text-block-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.text-block-card {
    display: flex;
    flex-direction: column;
    gap: 10px;
    padding: 14px;
    border-radius: 14px;
    border: 1px solid var(--border-color);
    background: linear-gradient(180deg, color-mix(in srgb, var(--bg-secondary) 88%, white 12%), var(--bg-secondary));
}

.scale-block {
    grid-template-columns: 1fr;
}

.scale-subgrid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.slider-group {
    padding: 14px;
    border-radius: 14px;
    border: 1px solid var(--border-color);
    background: linear-gradient(180deg, color-mix(in srgb, var(--bg-secondary) 88%, white 12%), var(--bg-secondary));
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.slider-group h4 {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    color: var(--text-secondary);
}

.slider-row {
    display: grid;
    grid-template-columns: 18px minmax(0, 1fr) 40px minmax(0, 70px);
    align-items: center;
    gap: 10px;
}

.slider-row span,
.slider-row output {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.8rem;
    color: var(--text-secondary);
}

.slider-row output {
    text-align: right;
    color: var(--text-primary);
}

.slider-row .color-hex-display {
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.7rem;
    color: var(--accent-engineering);
    text-align: right;
    padding: 2px 6px;
    border-radius: 4px;
    background: var(--bg-secondary);
    border: 1px solid var(--border-color);
}

.slider-row input[type="range"] {
    width: 100%;
    padding: 0;
    accent-color: var(--accent-engineering);
}

.badge {
    padding: 8px 12px;
    border-radius: 999px;
    border: 1px solid var(--border-color);
    background: var(--bg-secondary);
    color: var(--text-secondary);
    font: 600 0.76rem 'JetBrains Mono', monospace;
}

.preview-shell {
    flex: 1;
    min-height: 620px;
    border-radius: 18px;
    border: 1px solid var(--border-color);
    background:
        radial-gradient(circle at top left, color-mix(in srgb, var(--accent-engineering) 16%, transparent), transparent 38%),
        linear-gradient(180deg, color-mix(in srgb, var(--bg-secondary) 92%, white 8%), var(--bg-primary));
    padding: 22px;
}

.preview-stage {
    height: 100%;
    min-height: 576px;
    display: flex;
    align-items: center;
    justify-content: center;
    overflow: auto;
}

.paper-preview {
    width: min(100%, 880px);
    height: auto;
    max-height: 78vh;
    background: #ffffff;
    border-radius: 12px;
    box-shadow: 0 18px 40px rgba(0, 0, 0, 0.28);
}

.paper-preview .preview-sheet {
    fill: #ffffff;
}

.paper-preview .preview-outline {
    fill: none;
    stroke: rgba(15, 23, 42, 0.18);
    stroke-width: 1;
}

.paper-preview .preview-margin-guide {
    fill: none;
    stroke: rgba(15, 23, 42, 0.18);
    stroke-width: 1;
    stroke-dasharray: 6 5;
}

.grid-only.hidden,
.dot-only.hidden,
.axis-only.hidden {
    display: none;
}

@media (max-width: 1120px) {
    .tool-layout {
        grid-template-columns: 1fr;
    }

    .control-panel {
        position: relative;
        top: 0;
    }
}

@media (max-width: 720px) {
    .container {
        padding: 0 16px;
    }

    .control-grid,
    .stats-grid,
    .advanced-subgrid,
    .text-block-grid,
    .advanced-opacity-grid {
        grid-template-columns: 1fr;
    }

    .preview-shell {
        padding: 14px;
    }

    .preview-stage {
        min-height: 420px;
    }
}