.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: fuel-tank-capacity-calculator --- */
.tank-calculator-container {
    background: linear-gradient(135deg, #f5f7fa 0%, #c3cfe2 100%);
    min-height: auto;
    padding: 2rem 0;
}

.tank-calculator-card {
    background: rgba(255, 255, 255, 0.95);
    border-radius: 20px;
    box-shadow: 0 20px 40px rgba(0, 0, 0, 0.1);
    backdrop-filter: blur(10px);
    border: 1px solid rgba(255, 255, 255, 0.2);
}

.tank-input-group {
    position: relative;
    margin-bottom: 1.5rem;
}

.tank-input-group label {
    font-weight: 600;
    color: #2c3e50;
    margin-bottom: 0.5rem;
    display: block;
}

.tank-input-group .form-control,
.tank-input-group .form-select {
    border: 2px solid #e9ecef;
    border-radius: 12px;
    padding: 0.75rem 1rem;
    font-size: 1rem;
    transition: all 0.3s ease;
    background: white;
}

.tank-input-group .form-control:focus,
.tank-input-group .form-select:focus {
    border-color: #007bff;
    box-shadow: 0 0 0 0.2rem rgba(0, 123, 255, 0.25);
    transform: translateY(-2px);
}

.tank-input-group .input-group-text {
    background: #f8f9fa;
    border: 2px solid #e9ecef;
    border-left: none;
    border-radius: 0 12px 12px 0;
    font-weight: 600;
    color: #6c757d;
}

.tank-input-group .input-group .form-control {
    border-right: none;
    border-radius: 12px 0 0 12px;
}

.tank-shape-icon {
    width: 20px;
    height: 20px;
    margin-right: 8px;
    display: inline-block;
}

.tank-result-card {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 20px;
    padding: 2rem;
    margin-top: 2rem;
    box-shadow: 0 20px 40px rgba(102, 126, 234, 0.3);
}

.tank-result-value {
    font-size: 2.5rem;
    font-weight: 700;
    margin: 0.5rem 0;
    text-shadow: 0 2px 4px rgba(0, 0, 0, 0.3);
}

.tank-result-unit {
    font-size: 1.2rem;
    opacity: 0.9;
    font-weight: 500;
}

.tank-result-label {
    font-size: 1rem;
    opacity: 0.8;
    margin-bottom: 0.5rem;
}

.tank-calculate-btn {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
    border-radius: 12px;
    padding: 0.75rem 2rem;
    font-weight: 600;
    color: white;
    transition: all 0.3s ease;
    box-shadow: 0 4px 15px rgba(102, 126, 234, 0.4);
}

.tank-calculate-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 8px 25px rgba(102, 126, 234, 0.6);
    color: white;
}

.tank-reset-btn {
    background: #6c757d;
    border: none;
    border-radius: 12px;
    padding: 0.75rem 2rem;
    font-weight: 600;
    color: white;
    transition: all 0.3s ease;
}

.tank-reset-btn:hover {
    background: #5a6268;
    transform: translateY(-2px);
    color: white;
}

.tank-conversion-section {
    background: rgba(255, 255, 255, 0.8);
    border-radius: 15px;
    padding: 1.5rem;
    margin-top: 1rem;
}

.tank-conversion-item {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 0.5rem 0;
    border-bottom: 1px solid rgba(0, 0, 0, 0.1);
}

.tank-conversion-item:last-child {
    border-bottom: none;
}

.tank-conversion-label {
    font-weight: 500;
    color: #495057;
}

.tank-conversion-value {
    font-weight: 600;
    color: #007bff;
}

@media (max-width: 768px) {
    .tank-calculator-container {
        padding: 1rem 0;
    }
    
    .tank-result-value {
        font-size: 2rem;
    }
    
    .tank-calculate-btn,
    .tank-reset-btn {
        width: 100%;
        margin-bottom: 0.5rem;
    }
}