.formula-editor{margin-top:10px;border:1px solid var(--line);border-radius:28px;background:var(--card);box-shadow:var(--shadow);padding:14px}
.fe-head{display:flex;justify-content:space-between;gap:14px;align-items:center;padding:5px 6px 14px}.fe-head strong{font-size:1rem}.fe-head span{font-size:.72rem;color:var(--muted)}
.fe-grid{display:grid;grid-template-columns:1fr 1.05fr;gap:12px}.fe-pane{border:1px solid var(--line);border-radius:21px;background:#fffdf8;padding:18px;min-width:0}
.fe-label{display:flex;justify-content:space-between;gap:10px;align-items:center;margin-bottom:9px}.fe-label strong{font-size:.8rem}.fe-label span{font-size:.66rem;color:var(--muted)}
.fe-input{width:100%;min-height:116px;resize:vertical;border:1px solid var(--line);border-radius:16px;background:var(--paper);padding:16px;font:700 1.08rem/1.55 ui-monospace,SFMono-Regular,Menlo,Consolas,monospace;color:var(--ink);outline:none}.fe-input:focus{border-color:var(--green);box-shadow:0 0 0 3px rgba(13,103,83,.08)}
.fe-preview{min-height:160px;display:flex;align-items:center;justify-content:center;text-align:center;overflow:auto;border:1px solid #c9d8d1;border-radius:17px;background:linear-gradient(145deg,var(--mint2),#fff);padding:22px}.fe-formula{font-size:clamp(2rem,5vw,4rem);font-weight:850;letter-spacing:-.035em;line-height:1.25;white-space:pre-wrap}.fe-formula sub{font-size:.58em;vertical-align:-.32em}.fe-formula sup{font-size:.54em;vertical-align:.72em}.fe-arrow{color:var(--green);padding:0 .08em}.fe-coef{color:var(--amber);font-weight:950}.fe-state{font-size:.58em;color:var(--muted);font-weight:750}
.fe-keys,.fe-elements,.fe-examples,.fe-actions{display:flex;flex-wrap:wrap;gap:6px;margin-top:10px}.fe-keys button,.fe-elements button,.fe-examples button,.fe-actions button{border:1px solid var(--line);background:#fff;border-radius:999px;padding:7px 9px;font-size:.7rem;font-weight:850;color:var(--ink);cursor:pointer}.fe-elements button{width:37px;height:37px;padding:0;border-radius:11px;background:linear-gradient(145deg,var(--mint),#fff);color:var(--green);font-weight:950}.fe-keys button:hover,.fe-elements button:hover,.fe-examples button:hover,.fe-actions button:hover{border-color:var(--green);color:var(--green)}.fe-actions button.primary{background:var(--green);border-color:var(--green);color:#fff}
.fe-status{min-height:20px;font-size:.68rem;color:var(--green);font-weight:850;padding-top:6px}.fe-note{margin-top:10px;color:var(--muted);font-size:.72rem;line-height:1.5}.fe-atoms{display:flex;flex-wrap:wrap;gap:7px;margin-top:12px}.fe-atom{display:flex;align-items:center;gap:7px;border:1px solid var(--line);border-radius:13px;background:#fff;padding:7px 9px;text-decoration:none}.fe-atom b{width:31px;height:31px;border-radius:9px;background:var(--mint);display:grid;place-items:center;color:var(--green)}.fe-atom span{font-size:.68rem;color:var(--muted)}
@media(max-width:800px){.fe-grid{grid-template-columns:1fr}.fe-actions{display:grid;grid-template-columns:1fr 1fr}.fe-actions button{border-radius:12px}}