.tool-fullwidth {
    width: 100%;
    max-width: 100%;
    margin: 0;
    padding: 0;
}

/* Tool shell */
.engineering-tool {
    max-width: 100%;
    margin: 0 auto;
}

.engineering-tool.editor-section,
.editor-section.engineering-tool {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.engineering-tool .card:not(.result-card) {
    border: 1px solid var(--color-border, #e5e7eb);
    box-shadow: var(--shadow-sm, 0 1px 3px rgba(0, 0, 0, 0.06));
    border-radius: var(--radius, 12px);
    background: var(--color-surface, #fff);
}

.engineering-tool .card-body {
    padding: 1.25rem 1.35rem;
}

.engineering-tool .card-title {
    color: var(--color-text, #1f2937);
    font-weight: 700;
    font-size: 1.05rem;
}

.engineering-tool .form-control,
.engineering-tool .form-select,
.engineering-tool .select-input,
.engineering-tool textarea {
    border-radius: 8px;
    border: 1px solid var(--color-border, #e5e7eb);
}

.engineering-tool .form-control:focus,
.engineering-tool .form-select:focus,
.engineering-tool textarea:focus {
    border-color: var(--color-primary, #0d9488);
    box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
}

.engineering-tool .btn-primary {
    background: var(--color-primary, #0d9488);
    border-color: var(--color-primary, #0d9488);
}

.engineering-tool .btn-primary:hover {
    background: var(--color-primary-hover, #0f766e);
    border-color: var(--color-primary-hover, #0f766e);
}

.engineering-tool .alert {
    border-radius: 10px;
}

[data-theme="dark"] .engineering-tool .card:not(.result-card) {
    background: var(--color-surface, #1f2937);
    border-color: var(--color-border, #374151);
}

[data-theme="dark"] .engineering-tool .card-title,
[data-theme="dark"] .engineering-tool .form-label,
[data-theme="dark"] .engineering-tool {
    color: var(--color-text, #f9fafb);
}

[data-theme="dark"] .engineering-tool .text-muted,
[data-theme="dark"] .engineering-tool .form-text {
    color: var(--color-text-secondary, #9ca3af) !important;
}

[data-theme="dark"] .engineering-tool .form-control,
[data-theme="dark"] .engineering-tool .form-select,
[data-theme="dark"] .engineering-tool textarea {
    background: #111827;
    color: var(--color-text, #f9fafb);
    border-color: var(--color-border, #374151);
}

/* --- tool: online-ruler --- */
.tool-ruler-full {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.ruler-container {
    position: relative;
    width: 100%;
    height: 600px;
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    overflow: hidden;
}

.ruler-horizontal {
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 30px;
    background: #ffffff;
    border-bottom: 1px solid #dee2e6;
    z-index: 10;
}

.ruler-vertical {
    position: absolute;
    top: 0;
    left: 0;
    bottom: 0;
    width: 30px;
    background: #ffffff;
    border-right: 1px solid #dee2e6;
    z-index: 10;
}

.ruler-scale {
    position: relative;
    width: 100%;
    height: 100%;
}

.ruler-workspace {
    position: absolute;
    top: 30px;
    left: 30px;
    right: 0;
    bottom: 0;
    background: #ffffff;
    cursor: crosshair;
}

.workspace-content {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    height: 100%;
    color: #6c757d;
}

.workspace-text {
    font-size: 1.2rem;
    margin-bottom: 2rem;
}

.measurement-info {
    display: flex;
    gap: 2rem;
    background: rgba(0, 0, 0, 0.05);
    padding: 1rem 2rem;
    border-radius: 8px;
}

.measurement-item {
    display: flex;
    flex-direction: column;
    align-items: center;
}

.measurement-label {
    font-size: 0.9rem;
    color: #6c757d;
    margin-bottom: 0.5rem;
}

.measurement-value {
    font-size: 1.5rem;
    font-weight: bold;
    color: #28a745;
}

.crosshair {
    position: absolute;
    width: 1px;
    height: 1px;
    background: #dc3545;
    pointer-events: none;
    z-index: 20;
    display: none;
}

.crosshair::before,
.crosshair::after {
    content: '';
    position: absolute;
    background: #dc3545;
}

.crosshair::before {
    width: 1px;
    height: 20px;
    top: -10px;
    left: 0;
}

.crosshair::after {
    width: 20px;
    height: 1px;
    top: 0;
    left: -10px;
}

.ruler-mark {
    position: absolute;
    background: #28a745;
    color: #000000;
    font-size: 10px;
    font-weight: bold;
}

.ruler-mark.major {
    height: 15px;
    width: 1px;
}

.ruler-mark.minor {
    height: 8px;
    width: 1px;
}

.ruler-mark.horizontal {
    top: 0;
}

.ruler-mark.vertical {
    left: 0;
}

.ruler-label {
    position: absolute;
    font-size: 10px;
    font-weight: bold;
    color: #000000;
    white-space: nowrap;
}

.ruler-label.horizontal {
    top: 15px;
    transform: translateX(-50%);
}

.ruler-label.vertical {
    left: 15px;
    transform: translateY(-50%);
}

/* 响应式设计 */
@media (max-width: 768px) {
    .ruler-container {
        height: 400px;
    }
    
    .measurement-info {
        flex-direction: column;
        gap: 1rem;
    }
}

/* 全屏模式 */
.ruler-container.fullscreen {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    z-index: 9999;
    background: #ffffff;
}

.ruler-container.fullscreen .ruler-workspace {
    top: 30px;
    left: 30px;
}