.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 {
    border-radius: 8px;
    border: 1px solid var(--color-border, #e5e7eb);
}

.engineering-tool .form-control:focus,
.engineering-tool .form-select: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 {
    background: #111827;
    color: var(--color-text, #f9fafb);
    border-color: var(--color-border, #374151);
}

/* --- tool: weight-conversion-calculator --- */
.weight-converter-tool {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    min-height: auto;
    padding: 2rem 0;
}

.weight-converter-tool .container {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    padding: 2rem;
}

.conversion-card {
    border: none;
    border-radius: 15px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.conversion-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 40px rgba(0, 0, 0, 0.15);
}

.input-group-custom {
    border-radius: 10px;
    overflow: hidden;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
}

.input-group-custom .form-control {
    border: none;
    padding: 0.75rem 1rem;
    font-size: 1.1rem;
    font-weight: 500;
}

.input-group-custom .input-group-text {
    border: none;
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    font-weight: 600;
    padding: 0.75rem 1rem;
}

.btn-convert {
    border-radius: 10px;
    padding: 0.75rem 1.5rem;
    font-weight: 600;
    font-size: 1.1rem;
    transition: all 0.3s ease;
    border: none;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.btn-convert:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(0, 0, 0, 0.3);
}

.result-display {
    background: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    border-radius: 15px;
    padding: 1.5rem;
    margin-top: 1rem;
    border: 2px solid #e9ecef;
    animation: slideIn 0.5s ease;
}

@keyframes slideIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.unit-display {
    font-size: 0.9rem;
    color: #6c757d;
    font-weight: 500;
    margin-bottom: 0.5rem;
}

.preset-button {
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.3s ease;
    border: 2px solid transparent;
}

.preset-button:hover {
    transform: translateY(-2px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.2);
}

.info-badge {
    background: linear-gradient(45deg, #667eea, #764ba2);
    color: white;
    padding: 0.75rem 1rem;
    border-radius: 10px;
    font-weight: 500;
    display: inline-block;
}

.history-item {
    background: white;
    border-radius: 10px;
    padding: 1rem;
    margin-bottom: 0.5rem;
    border-left: 4px solid #667eea;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    transition: all 0.3s ease;
}

.history-item:hover {
    transform: translateX(5px);
    box-shadow: 0 5px 20px rgba(0, 0, 0, 0.15);
}

.weight-icon {
    font-size: 2rem;
    margin-bottom: 1rem;
    background: linear-gradient(45deg, #667eea, #764ba2);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
}

.conversion-formula {
    background: #f8f9fa;
    border-radius: 10px;
    padding: 1rem;
    margin-top: 1rem;
    border-left: 4px solid #28a745;
    font-family: 'Courier New', monospace;
    font-size: 0.9rem;
}

@media (max-width: 768px) {
    .weight-converter-tool .container {
        padding: 1rem;
        margin: 0.5rem;
    }
    
    .conversion-card {
        margin-bottom: 1rem;
    }
}