:root {
  --porcelain: #eef3f5;
  --paper: #f8faf9;
  --ink: #152329;
  --muted: #607079;
  --line: #bdcbd0;
  --cyan: #087f8c;
  --cyan-soft: #d7ecee;
  --signal: #df6538;
  --violet: #655f87;
  --error: #a13f32;
  --white: #ffffff;
  font-family: 'Avenir Next', 'Segoe UI Variable', 'PingFang SC', sans-serif;
  color: var(--ink);
  background: var(--porcelain);
  font-synthesis: none;
}

* {
  box-sizing: border-box;
}

[hidden] {
  display: none !important;
}

html {
  min-width: 320px;
  background: linear-gradient(
        90deg,
        rgba(8, 127, 140, 0.035) 1px,
        transparent 1px
      )
      0 0 / 28px 28px,
    var(--porcelain);
}

body {
  margin: 0;
  min-height: 100vh;
}
button,
input {
  font: inherit;
}

button {
  border: 1px solid var(--ink);
  border-radius: 2px;
  padding: 0.72rem 0.85rem;
  color: var(--ink);
  background: transparent;
  cursor: pointer;
  transition: transform 130ms ease, background-color 130ms ease,
    color 130ms ease;
}

button:hover:not(:disabled) {
  transform: translateY(-1px);
  background: var(--ink);
  color: var(--white);
}
button:disabled {
  cursor: not-allowed;
  opacity: 0.42;
}
button.primary {
  border-color: var(--cyan);
  background: var(--cyan);
  color: var(--white);
}
button:focus-visible,
input:focus-visible,
pre:focus-visible {
  outline: 3px solid color-mix(in srgb, var(--signal) 72%, white);
  outline-offset: 3px;
}

input {
  width: 100%;
  border: 0;
  border-bottom: 1px solid var(--ink);
  border-radius: 0;
  padding: 0.64rem 0;
  color: var(--ink);
  background: transparent;
}

input::placeholder {
  color: #8a9ba2;
}
.skip-link {
  position: fixed;
  left: 1rem;
  top: 1rem;
  z-index: 20;
  transform: translateY(-180%);
  padding: 0.7rem 1rem;
  background: var(--ink);
  color: white;
}
.skip-link:focus {
  transform: translateY(0);
}

.shell {
  width: min(1500px, 100%);
  margin: 0 auto;
  min-height: 100vh;
  padding: 1.6rem clamp(0.8rem, 3vw, 3rem) 1rem;
  display: flex;
  flex-direction: column;
}
.masthead {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 2rem;
  padding-bottom: 1.4rem;
  border-bottom: 1px solid var(--ink);
}
.brand-lockup {
  display: flex;
  align-items: center;
  gap: 1.1rem;
}
.brand-mark {
  display: grid;
  place-items: center;
  width: 3rem;
  height: 3rem;
  border: 1px solid var(--ink);
  clip-path: polygon(0 0, 82% 0, 100% 18%, 100% 100%, 18% 100%, 0 82%);
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-weight: 800;
  letter-spacing: -0.08em;
}
.eyebrow {
  margin: 0 0 0.38rem;
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.67rem;
  font-weight: 700;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--muted);
}
h1,
h2,
h3,
p {
  margin-top: 0;
}
h1 {
  margin-bottom: 0;
  max-width: 20ch;
  font-size: clamp(1.5rem, 3vw, 2.85rem);
  line-height: 1;
  letter-spacing: -0.05em;
}
h2 {
  margin-bottom: 0.65rem;
  font-size: clamp(1.35rem, 2vw, 2rem);
  letter-spacing: -0.035em;
}
h3 {
  letter-spacing: -0.025em;
}
.boundary {
  min-width: 13rem;
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 0.2rem 0.5rem;
  align-items: center;
  font-size: 0.74rem;
}
.boundary strong {
  grid-column: 2;
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-weight: 500;
  color: var(--muted);
}
.boundary-dot {
  width: 0.62rem;
  height: 0.62rem;
  border-radius: 50%;
  background: var(--cyan);
  box-shadow: 0 0 0 5px var(--cyan-soft);
}

.workspace {
  flex: 1;
  display: grid;
  grid-template-columns: minmax(20rem, 0.8fr) minmax(30rem, 1.45fr);
  min-height: 720px;
  border-bottom: 1px solid var(--ink);
}
.control-deck,
.evidence-panel {
  padding: clamp(1.35rem, 3vw, 2.8rem);
}
.control-deck {
  border-right: 1px solid var(--ink);
  background: rgba(248, 250, 249, 0.84);
}
.section-heading > p:last-child {
  max-width: 46ch;
  line-height: 1.65;
  color: var(--muted);
}
.session-gate {
  margin: 2rem 0;
  padding: 1rem;
  border-left: 3px solid var(--violet);
  background: color-mix(in srgb, var(--violet) 7%, var(--white));
}
.inline-control {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  gap: 0.7rem;
}
.field-label,
.session-gate label {
  display: block;
  margin-top: 0.8rem;
  font-size: 0.75rem;
  font-weight: 750;
  letter-spacing: 0.025em;
}
.field-note {
  margin: 0.65rem 0 0;
  font-size: 0.76rem;
  line-height: 1.5;
  color: var(--muted);
}
.mode-tabs {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  margin: 1.8rem 0 1.2rem;
  border-bottom: 1px solid var(--line);
}
.mode-tab {
  border: 0;
  border-bottom: 3px solid transparent;
  border-radius: 0;
  padding-inline: 0.3rem;
  color: var(--muted);
}
.mode-tab.active {
  border-bottom-color: var(--cyan);
  color: var(--ink);
  font-weight: 760;
}
.mode-tab:hover:not(:disabled) {
  transform: none;
  background: var(--cyan-soft);
  color: var(--ink);
}
.mode-panel {
  display: grid;
  gap: 0.7rem;
}
.control-group {
  display: grid;
  gap: 0.65rem;
  padding: 0.9rem 0 1.05rem;
  border-bottom: 1px solid var(--line);
}
.control-title {
  display: flex;
  align-items: baseline;
  gap: 0.55rem;
}
.control-title span {
  color: var(--cyan);
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.67rem;
}
.button-pair,
.button-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.55rem;
}
.button-grid {
  grid-template-columns: repeat(3, minmax(0, 1fr));
}
.trust-note {
  margin-top: 2rem;
  padding-top: 0.9rem;
  border-top: 1px solid var(--line);
}
.trust-note span {
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.66rem;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--violet);
}
.trust-note p {
  margin: 0.4rem 0 0;
  font-size: 0.78rem;
  line-height: 1.55;
  color: var(--muted);
}

.evidence-panel {
  position: relative;
  background: var(--paper);
}
.evidence-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 1rem;
  padding-bottom: 1rem;
  border-bottom: 1px solid var(--line);
}
.evidence-actions {
  display: grid;
  justify-items: end;
  gap: 0.55rem;
}
.ledger-meta {
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.64rem;
  color: var(--muted);
}
.evidence-buttons {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, auto));
  gap: 0.45rem;
}
.evidence-buttons button {
  padding: 0.52rem 0.65rem;
  font-size: 0.72rem;
}
.status-chip {
  border: 1px solid currentColor;
  border-radius: 999px;
  padding: 0.33rem 0.62rem;
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.66rem;
  color: var(--muted);
}
.status-chip[data-tone='busy'] {
  color: var(--signal);
}
.status-chip[data-tone='success'] {
  color: var(--cyan);
}
.status-chip[data-tone='failed'] {
  color: var(--error);
}
.empty-state {
  min-height: 480px;
  display: grid;
  place-content: center;
  justify-items: center;
  text-align: center;
}
.empty-state p {
  max-width: 38ch;
  line-height: 1.65;
  color: var(--muted);
}
.evidence-rail {
  width: min(25rem, 80%);
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  align-items: center;
  margin-bottom: 2.2rem;
}
.evidence-rail i {
  position: relative;
  height: 1px;
  background: var(--line);
}
.evidence-rail i::before {
  content: '';
  position: absolute;
  left: 0;
  top: -0.35rem;
  width: 0.7rem;
  height: 0.7rem;
  border: 1px solid var(--cyan);
  background: var(--paper);
  transform: rotate(45deg);
}
.ledger {
  margin: 0;
  padding: 1rem 0 0;
  list-style: none;
  counter-reset: evidence;
}
.ledger-entry {
  position: relative;
  padding: 1.1rem 0 1.2rem 3.5rem;
  border-bottom: 1px solid var(--line);
  counter-increment: evidence;
}
.ledger-entry::before {
  content: counter(evidence, decimal-leading-zero);
  position: absolute;
  left: 0;
  top: 1.15rem;
  width: 2.3rem;
  color: var(--cyan);
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.75rem;
}
.ledger-entry::after {
  content: '';
  position: absolute;
  left: 2.35rem;
  top: 1.05rem;
  bottom: 1rem;
  width: 1px;
  background: var(--line);
}
.ledger-entry header {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  align-items: baseline;
}
.ledger-entry h3 {
  margin-bottom: 0.35rem;
  font-size: 1rem;
}
.ledger-entry time {
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.65rem;
  color: var(--muted);
}
.ledger-entry pre {
  max-height: 28rem;
  overflow: auto;
  margin: 0.65rem 0 0;
  padding: 0.9rem;
  border-left: 2px solid var(--cyan);
  background: #e9f0f1;
  color: #203138;
  white-space: pre-wrap;
  overflow-wrap: anywhere;
  font: 0.72rem/1.55 ui-monospace, 'SFMono-Regular', Consolas, monospace;
}
.message {
  min-height: 1.4rem;
  margin-top: 1rem;
  font-size: 0.8rem;
  color: var(--muted);
}
.message[data-tone='error'] {
  color: var(--error);
}
footer {
  display: flex;
  justify-content: space-between;
  gap: 1rem;
  padding-top: 0.9rem;
  font-family: ui-monospace, 'SFMono-Regular', Consolas, monospace;
  font-size: 0.65rem;
  color: var(--muted);
}

@media (max-width: 900px) {
  .masthead,
  footer {
    flex-direction: column;
  }
  .boundary {
    align-self: flex-start;
  }
  .workspace {
    grid-template-columns: 1fr;
  }
  .control-deck {
    border-right: 0;
    border-bottom: 1px solid var(--ink);
  }
  .empty-state {
    min-height: 300px;
  }
}

@media (max-width: 520px) {
  .shell {
    padding-inline: 0.65rem;
  }
  .brand-mark {
    display: none;
  }
  .inline-control,
  .button-pair,
  .button-grid {
    grid-template-columns: 1fr;
  }
  .mode-tabs {
    font-size: 0.78rem;
  }
  .control-deck,
  .evidence-panel {
    padding: 1.1rem;
  }
  .evidence-header {
    flex-direction: column;
  }
  .evidence-actions {
    width: 100%;
    justify-items: start;
  }
  .evidence-buttons {
    width: 100%;
    grid-template-columns: 1fr 1fr;
  }
  .ledger-entry {
    padding-left: 2.8rem;
  }
  .ledger-entry::after {
    left: 1.9rem;
  }
}

@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
  }
}