:root{--ec-tool:#d97706;--ec-tool-dark:#b45309;--ec-gradient:linear-gradient(135deg,#d97706 0%,#f59e0b 100%);--ec-light:#fef3c7}[data-theme="dark"]{--ec-light:rgba(217,119,6,0.15)}.ec-mode-toggle{display:flex;border:1.5px solid var(--border);border-radius:0.5rem;overflow:hidden;margin-bottom:1rem}.ec-mode-btn{flex:1;padding:0.5rem 0.25rem;font-weight:600;font-size:0.65rem;border:none;cursor:pointer;background:var(--bg-secondary);color:var(--text-secondary);transition:all 0.15s;font-family:var(--font-sans);text-align:center}.ec-mode-btn.active{background:var(--ec-gradient);color:#fff}.ec-mode-btn:hover:not(.active){background:var(--bg-tertiary)}[data-theme="dark"] .ec-mode-btn{background:var(--bg-tertiary)}[data-theme="dark"] .ec-mode-btn.active{background:var(--ec-gradient);color:#fff}.ec-input-row{display:flex;gap:0.5rem;align-items:flex-end;margin-bottom:0.5rem}.ec-input-group{flex:1;min-width:0}.ec-input-label{display:block;font-size:0.6875rem;font-weight:600;color:var(--text-secondary);text-transform:uppercase;letter-spacing:0.05em;margin-bottom:0.25rem}.ec-input{width:100%;padding:0.5rem;font-size:0.875rem;font-family:var(--font-mono);border:1.5px solid var(--border);border-radius:0.375rem;background:var(--bg-primary);color:var(--text-primary);text-align:center;transition:border-color 0.15s}.ec-input:focus{outline:none;border-color:var(--ec-tool);box-shadow:0 0 0 2px rgba(217,119,6,0.1)}.ec-rule-select{width:100%;padding:0.5rem 0.75rem;font-size:0.8125rem;border:1.5px solid var(--border);border-radius:0.375rem;background:var(--bg-primary);color:var(--text-primary);font-family:var(--font-sans);cursor:pointer}.ec-rule-select:focus{outline:none;border-color:var(--ec-tool)}.ec-preview{min-height:2.5rem;padding:0.5rem 0.75rem;border:1.5px dashed var(--border);border-radius:0.5rem;background:var(--bg-secondary);font-size:1rem;display:flex;align-items:center;justify-content:center;overflow-x:auto}.ec-preview .katex{font-size:1em}.ec-output-tabs{display:flex;border-bottom:1.5px solid var(--border);background:var(--bg-secondary);border-radius:0.75rem 0.75rem 0 0;overflow:hidden}.ec-output-tab{flex:1;padding:0.625rem 0.5rem;font-size:0.75rem;font-weight:600;border:none;cursor:pointer;background:transparent;color:var(--text-secondary);transition:all 0.15s;font-family:var(--font-sans);text-align:center;position:relative}.ec-output-tab.active{color:var(--ec-tool);background:var(--bg-primary)}.ec-output-tab.active::after{content:"";position:absolute;bottom:0;left:0;right:0;height:2px;background:var(--ec-tool)}.ec-output-tab:hover:not(.active){background:var(--bg-tertiary)}.ec-panel{display:none}.ec-panel.active{display:block}.ec-mode-form{display:none}.ec-mode-form.active{display:block}.ec-step{display:flex;gap:0.75rem;padding:0.75rem;margin:0.5rem 0;background:var(--bg-secondary);border-radius:0.5rem;border-left:3px solid var(--ec-tool);transition:background 0.15s}.ec-step:hover{background:var(--bg-tertiary)}.ec-step-number{width:1.5rem;height:1.5rem;border-radius:50%;background:var(--ec-gradient);color:#fff;display:flex;align-items:center;justify-content:center;font-size:0.6875rem;font-weight:700;flex-shrink:0;margin-top:0.125rem}.ec-step-content{flex:1;min-width:0}.ec-step-desc{font-size:0.8125rem;font-weight:500;color:var(--text-primary);margin-bottom:0.375rem}.ec-step-math{overflow-x:auto;padding:0.25rem 0}.ec-step-math .katex{font-size:0.9em}.ec-step-math .katex-display{margin:0;overflow-x:auto;overflow-y:hidden}.ec-rule-badge{display:inline-block;background:var(--ec-gradient);color:#fff;padding:0.2rem 0.625rem;border-radius:0.75rem;font-size:0.6875rem;font-weight:600}.ec-law-card{padding:0.75rem;margin:0.5rem 0;background:var(--bg-secondary);border-radius:0.5rem;border-left:3px solid var(--ec-tool)}.ec-law-card h4{font-size:0.8125rem;font-weight:600;color:var(--text-primary);margin:0 0 0.375rem}.ec-law-formula{padding:0.375rem 0.5rem;background:var(--ec-light);border-radius:0.375rem;margin-bottom:0.375rem;overflow-x:auto}.ec-law-formula .katex{font-size:0.85em}.ec-law-example{font-size:0.75rem;color:var(--text-secondary)}.ec-examples{display:flex;flex-wrap:wrap;gap:0.375rem}.ec-example-chip{padding:0.3rem 0.625rem;font-size:0.6875rem;font-weight:500;border-radius:2rem;border:1px solid var(--border);background:var(--bg-secondary);color:var(--text-secondary);cursor:pointer;transition:all 0.15s;font-family:var(--font-mono)}.ec-example-chip:hover{background:var(--ec-light);color:var(--ec-tool);border-color:var(--ec-tool)}.ec-laws-grid{display:grid;grid-template-columns:repeat(auto-fit,minmax(220px,1fr));gap:0.75rem;margin:1rem 0}.ec-edu-card{padding:1rem;background:var(--bg-secondary);border-radius:0.5rem}.ec-edu-card h4{font-size:0.875rem;font-weight:600;color:var(--text-primary);margin:0 0 0.375rem}.ec-edu-card p{font-size:0.8125rem;color:var(--text-secondary);margin:0;line-height:1.6}.ec-callout{display:flex;gap:0.75rem;padding:1rem;border-radius:0.5rem;margin:1rem 0}.ec-callout-icon{font-size:1.25rem;flex-shrink:0}.ec-callout-text{font-size:0.8125rem;line-height:1.6;color:var(--text-secondary)}.ec-callout-insight{background:#fffbeb;border-left:3px solid #d97706}.ec-callout-tip{background:#ecfdf5;border-left:3px solid #10b981}[data-theme="dark"] .ec-callout-insight{background:rgba(217,119,6,0.1)}[data-theme="dark"] .ec-callout-tip{background:rgba(16,185,129,0.1)}.ec-anim{opacity:0;transform:translateY(1rem);transition:opacity 0.5s ease,transform 0.5s ease}.ec-anim.ec-visible{opacity:1;transform:translateY(0)}.ec-anim-d1{transition-delay:0.1s}.ec-anim-d2{transition-delay:0.2s}.ec-anim-d3{transition-delay:0.3s}.ec-anim-d4{transition-delay:0.4s}@media (prefers-reduced-motion:reduce){.ec-anim{opacity:1;transform:none;transition:none}}@media (max-width:640px){.ec-input-row{flex-direction:column;gap:0.375rem}.ec-laws-grid{grid-template-columns:1fr}}