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

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

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

.academic-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);
}

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

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

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

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

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

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

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

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

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

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

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

/* --- tool: absolute-value-calculator --- */
.absolute-value-calculator {
    max-width: 800px;
    margin: 0 auto;
}

.tab-content {
    background: #fff;
    border: 1px solid #dee2e6;
    border-top: none;
    border-radius: 0 0 0.375rem 0.375rem;
    padding: 2rem;
}

.nav-tabs .nav-link {
    border: none;
    color: #6c757d;
    font-weight: 500;
}

.nav-tabs .nav-link.active {
    color: #0d6efd;
    background: #fff;
    border-bottom: 3px solid #0d6efd;
}

.result-box {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 0.375rem;
    padding: 1rem;
    margin-top: 1rem;
}

.absolute-result {
    font-family: 'Courier New', monospace;
    font-size: 1.1rem;
    color: #0d6efd;
}

.calculation-steps {
    font-size: 0.9rem;
    color: #6c757d;
    margin-top: 0.5rem;
}

.decimal-result {
    font-size: 1.2rem;
    font-weight: 600;
    color: #198754;
}

.precision-info {
    background: #e7f3ff;
    border: 1px solid #b3d9ff;
    border-radius: 0.375rem;
    padding: 0.75rem;
    margin-top: 1rem;
    font-size: 0.9rem;
    color: #0056b3;
}

.positive-number {
    color: #198754;
}

.negative-number {
    color: #dc3545;
}

.zero-number {
    color: #6b7280;
}

.formula-display {
    background: #f8f9fa;
    border: 1px solid #dee2e6;
    border-radius: 0.25rem;
    padding: 1rem;
    font-family: 'Times New Roman', serif;
    font-style: italic;
    text-align: center;
    margin: 1rem 0;
}

.number-line {
    background: linear-gradient(to right, #dc3545 0%, #6b7280 50%, #198754 100%);
    height: 20px;
    border-radius: 10px;
    position: relative;
    margin: 10px 0;
}

.number-line-marker {
    position: absolute;
    top: -5px;
    width: 2px;
    height: 30px;
    background: #000;
}

.number-line-value {
    position: absolute;
    top: -25px;
    font-size: 0.8rem;
    font-weight: bold;
}

.complex-analysis {
    background: #fffbf0;
    border: 1px solid #ffeaa7;
    border-radius: 0.375rem;
    padding: 1rem;
    margin-top: 1rem;
}

.complex-result {
    font-family: 'Courier New', monospace;
    color: #d63031;
}