.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: sphere-filling-volume-calculator --- */
.sphere-calculator {
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

.calculator-section {
    display: none;
}

.calculator-section.active {
    display: block;
}

.calc-type-btn {
    transition: all 0.3s ease;
    border-radius: 8px;
}

.calc-type-btn.active {
    background-color: #0d6efd;
    border-color: #0d6efd;
    color: white;
    transform: translateY(-2px);
    box-shadow: 0 4px 8px rgba(13, 110, 253, 0.3);
}

.calc-type-btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.result-box {
    animation: fadeIn 0.5s ease-in;
}

@keyframes fadeIn {
    from { opacity: 0; transform: translateY(10px); }
    to { opacity: 1; transform: translateY(0); }
}

.card {
    border-radius: 12px;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.1);
    border: none;
}

.card-header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    border-radius: 12px 12px 0 0 !important;
    border: none;
}

.form-control, .form-select {
    border-radius: 8px;
    border: 2px solid #e9ecef;
    transition: all 0.3s ease;
}

.form-control:focus, .form-select:focus {
    border-color: #0d6efd;
    box-shadow: 0 0 0 0.2rem rgba(13, 110, 253, 0.25);
}

.btn {
    border-radius: 8px;
    font-weight: 500;
    transition: all 0.3s ease;
}

.btn-primary {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    border: none;
}

.btn-primary:hover {
    background: linear-gradient(135deg, #5a6fd8 0%, #6a4190 100%);
    transform: translateY(-1px);
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.2);
}

.alert {
    border-radius: 8px;
    border: none;
}

.alert-info {
    background: linear-gradient(135deg, #d1ecf1 0%, #bee5eb 100%);
    color: #0c5460;
}

.alert-success {
    background: linear-gradient(135deg, #d4edda 0%, #c3e6cb 100%);
    color: #155724;
}

.alert-warning {
    background: linear-gradient(135deg, #fff3cd 0%, #ffeaa7 100%);
    color: #856404;
}

.form-text {
    font-size: 0.875rem;
    color: #6c757d;
}

h6 {
    color: #495057;
    font-weight: 600;
}

.list-unstyled li {
    margin-bottom: 0.5rem;
    padding: 0.25rem 0;
}

@media (max-width: 768px) {
    .calc-type-btn {
        font-size: 0.875rem;
        padding: 0.5rem;
    }
    
    .d-flex.gap-2 {
        flex-wrap: wrap;
    }
    
    .d-flex.gap-2 .btn {
        flex: 1;
        min-width: 60px;
    }
}