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

.calculator-container {
    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);
}

.preview {
    text-align: center;
    padding: 2rem;
    background: linear-gradient(45deg, #f093fb 0%, #f5576c 100%);
    border-radius: 15px;
    color: white;
    margin-bottom: 2rem;
}

.icon-hero { font-size: 4rem; margin-bottom: 1rem; display: block; }

.input-group-custom { position: relative; margin-bottom: 1.5rem; }
.input-group-custom .form-control { border: 2px solid #e9ecef; border-radius: 10px; padding: 12px 15px; font-size: 1.1rem; transition: all 0.3s ease; }
.input-group-custom .form-control:focus { border-color: #667eea; box-shadow: 0 0 0 0.2rem rgba(102, 126, 234, 0.25); }

.btn-calculate { background: linear-gradient(45deg, #667eea, #764ba2); border: none; border-radius: 10px; padding: 12px 30px; font-size: 1.1rem; font-weight: 600; transition: all 0.3s ease; }
.btn-calculate:hover { transform: translateY(-2px); box-shadow: 0 10px 20px rgba(102, 126, 234, 0.3); }

.result-box { background: linear-gradient(135deg, #667eea 0%, #764ba2 100%); border-radius: 15px; padding: 1.5rem; color: white; margin-top: 1.5rem; }
.result-item { background: rgba(255, 255, 255, 0.1); border-radius: 10px; padding: 1rem; margin-bottom: 1rem; backdrop-filter: blur(10px); }
.result-value { font-size: 1.2rem; font-weight: 600; }

.formula-card { background: linear-gradient(135deg, #ffecd2 0%, #fcb69f 100%); border-radius: 15px; border: none; }
.formula-item { background: rgba(255, 255, 255, 0.7); border-radius: 8px; padding: 0.8rem; margin-bottom: 0.5rem; font-size: 0.95rem; }

.badge-factor { background: rgba(255,255,255,.2); border: 1px solid rgba(255,255,255,.4); }

@media (max-width: 768px) { .equivalent-fractions{ padding: 1rem 0; } .icon-hero{ font-size: 3rem; } }