:root{--bg: #0f1117;--panel: #171a23;--panel-2: #1d212c;--border: #2a2f3c;--text: #e6e8ee;--muted: #8b91a3;--accent: #f5b942;--accent-soft: #f5b94222;--current: #4ea1ff;--current-soft: #4ea1ff1f;--root: #6ee7a8;--danger: #ff6b6b;--radius: 12px;--rail: 40px}*{box-sizing:border-box}html,body{margin:0;background:var(--bg);color:var(--text);font-family:ui-sans-serif,system-ui,-apple-system,Segoe UI,Roboto,sans-serif;line-height:1.5}.app{max-width:680px;margin:0 auto;padding:2.5rem 1.25rem 4rem}.app__header{margin-bottom:1.75rem}.app__title{margin:0;font-size:1.9rem;letter-spacing:-.02em}.app__tagline{margin:.4rem 0 0;color:var(--muted);max-width:46ch}.app__muted{color:var(--muted);font-size:.9rem}.push{display:flex;gap:.5rem;margin-bottom:2rem}.push__input{flex:1;padding:.75rem .9rem;background:var(--panel);border:1px solid var(--border);border-radius:var(--radius);color:var(--text);font-size:1rem;outline:none;transition:border-color .15s}.push__input:focus{border-color:var(--accent)}.push__input::placeholder{color:var(--muted)}.push__button{padding:0 1.25rem;background:var(--accent);color:#1a1300;border:none;border-radius:var(--radius);font-weight:650;font-size:.95rem;cursor:pointer;transition:opacity .15s,transform .05s}.push__button:hover:not(:disabled){opacity:.9}.push__button:active:not(:disabled){transform:translateY(1px)}.push__button:disabled{opacity:.4;cursor:not-allowed}.empty{padding:2.5rem 1.25rem;text-align:center;border:1px dashed var(--border);border-radius:var(--radius)}.empty__line{margin:0;font-weight:600}.empty__hint{margin:.35rem 0 0;color:var(--muted);font-size:.9rem}.trace{list-style:none;margin:0;padding:0}.frame{position:relative;display:flex;gap:.85rem;padding:.2rem 0}.frame__rail{position:relative;flex:0 0 var(--rail);display:flex;justify-content:center}.frame__rail:before{content:"";position:absolute;top:0;bottom:0;width:2px;background:var(--border)}.frame:first-child .frame__rail:before{top:1.35rem}.frame:last-child .frame__rail:before{bottom:calc(100% - 1.35rem)}.frame__depth{position:relative;z-index:1;margin-top:.7rem;width:1.7rem;height:1.7rem;display:grid;place-items:center;background:var(--panel-2);border:2px solid var(--border);border-radius:50%;font-size:.8rem;font-variant-numeric:tabular-nums;color:var(--muted)}.frame__body{flex:1;margin:.4rem 0;padding:.85rem 1rem;background:var(--panel);border:1px solid var(--border);border-radius:var(--radius)}.frame__head{margin-bottom:.25rem}.frame__tag{font-size:.7rem;text-transform:uppercase;letter-spacing:.06em;color:var(--muted);font-weight:650}.frame__tag--current{color:var(--current)}.frame__tag--root{color:var(--root)}.frame__title{margin:0;font-size:1.05rem;font-weight:550}.frame__note{margin:.3rem 0 0;color:var(--muted);font-size:.9rem}.frame--current .frame__body{background:var(--current-soft);border-color:var(--current)}.frame--current .frame__depth{border-color:var(--current);color:var(--current)}.frame--root .frame__depth{border-color:var(--root);color:var(--root)}.frame__pop{align-self:center;padding:.5rem .8rem;background:transparent;border:1px solid var(--current);color:var(--current);border-radius:var(--radius);font-weight:600;font-size:.85rem;cursor:pointer;white-space:nowrap;transition:background .15s}.frame__pop:hover{background:var(--current-soft)}.app__footer{display:flex;align-items:center;justify-content:space-between;margin-top:1.75rem;padding-top:1rem;border-top:1px solid var(--border)}.app__clear{background:transparent;border:none;color:var(--muted);font-size:.85rem;cursor:pointer;text-decoration:underline;text-underline-offset:3px}.app__clear:hover{color:var(--danger)}