/* rail — reasoning, timeline, gates, composer */
.rail { overflow: hidden; }
.rail .btn span { display: inline; }
.rail-sr { position: absolute; width: 1px; height: 1px; overflow: hidden; clip: rect(0 0 0 0); }
.rail-muted { color: var(--muted-fg); font-size: 12px; }
.rail-sub { font-size: 10.5px; font-weight: 600; letter-spacing: .05em; text-transform: uppercase; color: var(--muted-fg); margin: 10px 0 5px; }
.rail-link { display: inline-flex; align-items: center; gap: 4px; border: 0; background: none; padding: 0; font-size: 12px; color: var(--primary); text-align: left; }
.rail-link:hover { text-decoration: underline; }
.rail-empty { text-align: center; color: var(--muted-fg); padding: 36px 18px; display: flex; flex-direction: column; align-items: center; gap: 6px; }
.rail-empty p { max-width: 260px; }

.rail-tabs { display: flex; border-bottom: 1px solid var(--border); flex-shrink: 0; }
.rail-tab { flex: 1; display: flex; align-items: center; justify-content: center; gap: 6px; padding: 11px 6px; border: 0; background: none;
  font-size: 12.5px; color: var(--muted-fg); border-bottom: 2px solid transparent; position: relative; }
.rail-tab:hover { color: var(--fg); background: var(--muted); }
.rail-tab.on { color: var(--primary); font-weight: 600; border-bottom-color: var(--primary); }
.rail-badge { font-style: normal; font-size: 10px; font-weight: 600; background: var(--warn); color: #fff; border-radius: 999px; padding: 0 6px; min-width: 16px; text-align: center; }
.rail-await { display: flex; align-items: center; gap: 8px; padding: 7px 12px; background: var(--warn-bg); color: var(--warn); font-size: 12px; border-bottom: 1px solid var(--border); flex-shrink: 0; }
.rail-await span { flex: 1; }
.rail-await .btn { margin-left: auto; }
.rail-scroll { flex: 1; min-height: 0; overflow-y: auto; padding: 12px; }

/* reasoning */
.rail-run-head { display: flex; align-items: center; gap: 8px; }
.rail-pick { flex: 1; min-width: 0; }
.rail-pick select { width: 100%; padding: 6px 8px; border: 1px solid var(--border-strong); border-radius: var(--radius-sm); background: var(--card); font-size: 12.5px; }
.rail-stats { display: flex; flex-wrap: wrap; gap: 4px 12px; margin: 10px 0 6px; font-size: 11.5px; color: var(--muted-fg); }
.rail-stat b { color: var(--fg); font-weight: 600; }
.rail-actions-row { display: flex; gap: 6px; margin-bottom: 8px; flex-wrap: wrap; }
.rail-trace { list-style: none; position: relative; margin: 6px 0 0; }
.rail-step { display: flex; gap: 10px; padding-bottom: 14px; position: relative; animation: rail-in .35s ease both; }
.rail-step:not(:last-child)::before { content: ""; position: absolute; left: 13px; top: 28px; bottom: 0; width: 2px; background: var(--border); }
.rail-step-ico { width: 28px; height: 28px; border-radius: 50%; flex-shrink: 0; display: grid; place-items: center; background: var(--muted); color: var(--muted-fg); }
.rail-step-main { flex: 1; min-width: 0; }
.rail-step-head { display: flex; align-items: baseline; gap: 8px; }
.rail-step-kind { font-size: 11px; font-weight: 600; letter-spacing: .05em; text-transform: uppercase; }
.rail-step-ms { margin-left: auto; font-size: 11px; color: var(--faint); font-variant-numeric: tabular-nums; }
.rail-step-text { font-size: 12.8px; line-height: 1.55; margin-top: 2px; overflow-wrap: anywhere; white-space: pre-wrap; }
.rail-mono { font-family: var(--font-mono); font-size: 11.5px; background: var(--muted); border: 1px solid var(--border); border-radius: var(--radius-sm);
  padding: 7px 9px; margin-top: 4px; white-space: pre-wrap; overflow-wrap: anywhere; max-height: 220px; overflow: auto; }
.k-plan .rail-step-ico { background: var(--secondary-50); color: var(--secondary); } .k-plan .rail-step-kind { color: var(--secondary); }
.k-read .rail-step-ico { background: var(--info-bg); color: var(--info); } .k-read .rail-step-kind { color: var(--info); }
.k-tool .rail-step-ico { background: var(--muted); color: var(--fg); } .k-tool .rail-step-kind { color: var(--muted-fg); }
.k-reason .rail-step-ico { background: var(--primary-50); color: var(--primary); } .k-reason .rail-step-kind { color: var(--primary); }
.k-check .rail-step-ico { background: var(--ok-bg); color: var(--ok); } .k-check .rail-step-kind { color: var(--ok); }
.k-alt .rail-step-ico { background: var(--warn-bg); color: var(--warn); } .k-alt .rail-step-kind { color: var(--warn); }
.k-decide .rail-step-ico { background: var(--primary); color: var(--primary-fg); } .k-decide .rail-step-kind { color: var(--primary-700); }
.rail-alts { margin-top: 6px; padding: 8px 10px; background: var(--warn-bg); border-radius: var(--radius-sm); }
.rail-alts .rail-sub { margin-top: 0; color: var(--warn); }
.rail-alt { display: flex; gap: 8px; padding: 3px 0; font-size: 12.3px; }
.rail-alt-x { color: var(--bad); margin-top: 2px; }
.rail-alt-why { color: var(--muted-fg); }
.rail-chips { display: flex; flex-wrap: wrap; gap: 5px; margin-top: 6px; }
.rail-chip { display: inline-flex; align-items: center; gap: 4px; padding: 2px 8px; border-radius: 999px; border: 1px solid var(--border); background: var(--card);
  font-size: 11.5px; max-width: 100%; text-align: left; }
.rail-chip span { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }
.rail-chip em { font-style: normal; color: var(--ok); font-weight: 600; }
.rail-chip.src { background: var(--info-bg); border-color: transparent; color: var(--info); }
.rail-chip.src:not(.static):hover { border-color: var(--info); }
.rail-chip.prompt { background: var(--primary-50); border-color: transparent; color: var(--primary-700); white-space: normal; }
.rail-chip.prompt:hover { border-color: var(--primary-300); }
.rail-chips.tags { margin-top: 10px; }
.rail-conf { margin-top: 6px; padding: 10px 12px; border: 1px solid var(--border); border-radius: var(--radius); position: relative; }
.rail-conf .rail-sub { margin-top: 0; }
.rail-meter { height: 8px; background: var(--muted); border-radius: 999px; overflow: hidden; }
.rail-meter i { display: block; height: 100%; border-radius: 999px; background: var(--ok); }
.rail-meter.warn i { background: var(--warn); } .rail-meter.bad i { background: var(--bad); }
.rail-conf-num { position: absolute; top: 8px; right: 12px; font-weight: 600; font-size: 13px; }
.rail-conf-num.ok { color: var(--ok); } .rail-conf-num.warn { color: var(--warn); } .rail-conf-num.bad { color: var(--bad); }
.rail-factors { list-style: none; margin-top: 8px; font-size: 12px; }
.rail-factors li { padding: 1px 0; } .rail-factors.up b { color: var(--ok); } .rail-factors.down b { color: var(--bad); }
.rail-mind { margin-top: 10px; padding: 10px 12px; background: var(--secondary-50); border-radius: var(--radius); font-size: 12.5px; }
.rail-mind .rail-sub { margin-top: 0; color: var(--secondary); }
.rail-replay-note { margin: 4px 0 0 38px; }
.rail-bar { height: 4px; border-radius: 999px; background: var(--muted); overflow: hidden; margin-top: 8px; width: 70%; }
.rail-bar i { display: block; height: 100%; width: 40%; background: var(--grad); border-radius: 999px; animation: rail-slide 1.2s ease-in-out infinite; }
.rail-spin { width: 14px; height: 14px; border: 2px solid var(--primary-100); border-top-color: var(--primary); border-radius: 50%; animation: rail-rot .8s linear infinite; }
@keyframes rail-in { from { opacity: 0; transform: translateY(6px); } to { opacity: 1; transform: none; } }
@keyframes rail-slide { 0% { margin-left: -40%; } 100% { margin-left: 100%; } }
@keyframes rail-rot { to { transform: rotate(360deg); } }
@media (prefers-reduced-motion: reduce) { .rail-step, .rail-bar i, .rail-spin { animation: none; } }

/* gate */
.rail-gate { border: 1px solid var(--border-strong); border-radius: var(--radius); background: var(--card); overflow: hidden; }
.rail-gate.open { border-color: var(--warn); box-shadow: 0 0 0 3px var(--warn-bg); }
.rail-gate-head { display: flex; align-items: center; gap: 6px; padding: 8px 12px; background: var(--muted); font-size: 11.5px; font-weight: 600; color: var(--muted-fg); }
.rail-gate.open .rail-gate-head { background: var(--warn-bg); color: var(--warn); }
.rail-stepper { margin-left: auto; display: flex; align-items: center; gap: 4px; font-weight: 500; }
.rail-stepper .rot { transform: rotate(180deg); }
.rail-gate-body { padding: 12px; }
.rail-gate-action { font-weight: 600; font-size: 13.5px; }
.rail-gate-target { display: flex; gap: 6px; align-items: center; margin: 4px 0 8px; font-size: 12px; color: var(--muted-fg); }
.rail-warn { display: flex; gap: 6px; padding: 7px 9px; margin-bottom: 8px; border-radius: var(--radius-sm); background: var(--bad-bg); color: var(--bad); font-size: 12px; }
.rail-diffbar { display: flex; justify-content: space-between; align-items: center; font-size: 11.5px; color: var(--muted-fg); margin-bottom: 5px; }
.rail-diffbar b.ins { color: var(--ok); } .rail-diffbar b.del { color: var(--bad); }
.rail-clause { font-size: 12.8px; line-height: 1.65; padding: 10px 12px; background: var(--bg); border: 1px solid var(--border); border-radius: var(--radius-sm); overflow-wrap: anywhere; white-space: pre-wrap; max-height: 300px; overflow: auto; }
.rail-block + .rail-block { margin-top: 6px; }
.rail-block .rail-sub { margin: 0 0 3px; }
.rail-block.out .rail-clause { background: var(--bad-bg); } .rail-block.in .rail-clause { background: var(--ok-bg); }
.d-ins { background: var(--ok-bg); color: var(--ok); text-decoration: none; border-radius: 3px; padding: 0 1px; font-weight: 500; }
.d-del { background: var(--bad-bg); color: var(--bad); text-decoration: line-through; border-radius: 3px; padding: 0 1px; }
.rail-edit { width: 100%; min-height: 130px; padding: 10px; border: 1px solid var(--primary-300); border-radius: var(--radius-sm); font-size: 12.8px; line-height: 1.6; resize: vertical; }
.rail-impact { margin-top: 10px; padding: 8px 10px; background: var(--warn-bg); border-radius: var(--radius-sm); }
.rail-impact .rail-sub { margin-top: 0; color: var(--warn); }
.rail-impact-row { display: flex; flex-direction: column; gap: 2px; padding: 5px 0; font-size: 12px; border-top: 1px solid hsl(38 60% 80%); }
.rail-impact-row:first-of-type { border-top: 0; }
.rail-gate-actions { display: flex; flex-wrap: wrap; gap: 6px; margin-top: 12px; align-items: center; }
.rail-keys { margin-left: auto; font-size: 11px; }
.rail-decided { margin-top: 12px; padding: 8px 10px; border-radius: var(--radius-sm); font-size: 12.5px; font-weight: 500; display: flex; gap: 6px; align-items: center; flex-wrap: wrap; }
.rail-decided.ok { background: var(--ok-bg); color: var(--ok); } .rail-decided.bad { background: var(--bad-bg); color: var(--bad); } .rail-decided.info { background: var(--info-bg); color: var(--info); }
.rail-list-title { margin-top: 16px; }
.rail-gatelist { list-style: none; display: flex; flex-direction: column; gap: 4px; }
.rail-gaterow { width: 100%; display: flex; align-items: center; gap: 8px; padding: 7px 9px; border: 1px solid var(--border); border-radius: var(--radius-sm); background: var(--card); text-align: left; font-size: 12px; }
.rail-gaterow:hover { background: var(--muted); }
.rail-gaterow-t { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

/* timeline */
.rail-filters { display: flex; gap: 4px; margin-bottom: 10px; }
.rail-filter { padding: 4px 11px; border-radius: 999px; border: 1px solid var(--border); background: var(--card); font-size: 12px; text-transform: capitalize; }
.rail-filter.on { background: var(--primary-50); border-color: var(--primary-300); color: var(--primary-700); font-weight: 600; }
.rail-timeline { list-style: none; }
.rail-evt { display: flex; gap: 9px; padding: 0 0 12px; position: relative; }
.rail-evt:not(:last-child)::before { content: ""; position: absolute; left: 12px; top: 26px; bottom: 0; width: 1px; background: var(--border); }
.rail-av { width: 25px; height: 25px; border-radius: 50%; flex-shrink: 0; display: grid; place-items: center; font-size: 10px; font-weight: 600; background: var(--secondary-50); color: var(--secondary); }
.rail-av.agent { background: var(--primary-50); color: var(--primary); }
.rail-evt-main { min-width: 0; flex: 1; }
.rail-evt-head { display: flex; gap: 8px; align-items: baseline; font-size: 11.5px; }
.rail-evt-actor { font-weight: 600; font-size: 12px; }
.rail-evt-kind { display: inline-flex; gap: 3px; align-items: center; color: var(--muted-fg); }
.rail-evt-t { margin-left: auto; color: var(--faint); font-size: 11px; white-space: nowrap; }
.rail-evt-text { font-size: 12.5px; overflow-wrap: anywhere; }
.rail-evt-links { display: flex; gap: 12px; margin-top: 3px; }
.rail-more { width: 100%; justify-content: center; }

/* composer */
.rail-composer { border-top: 1px solid var(--border); padding: 10px 12px; flex-shrink: 0; background: var(--card); }
.rail-composer .rail-chips { margin: 0 0 8px; flex-wrap: nowrap; overflow-x: auto; scrollbar-width: thin; padding-bottom: 2px; }
.rail-composer .rail-chip.prompt { white-space: nowrap; flex-shrink: 0; }
.rail-composer textarea { width: 100%; resize: none; padding: 8px 10px; border: 1px solid var(--border-strong); border-radius: var(--radius-sm); font-size: 12.8px; line-height: 1.5; }
.rail-composer textarea:focus-visible { border-color: var(--primary-300); }
.rail-composer-row { display: flex; align-items: center; justify-content: space-between; margin-top: 6px; }
@media (max-width: 820px) { .rail-scroll { max-height: 50vh; } }

.rail-follow { display: flex; align-items: baseline; justify-content: space-between; gap: 8px; margin: 6px 0 2px; font-size: 11.5px; }
.rail-follow .rail-muted { overflow: hidden; text-overflow: ellipsis; white-space: nowrap; min-width: 0; }
.rail-follow .rail-link { color: var(--muted-fg); flex-shrink: 0; }