:root {
  --bg: #eef2f6;
  --surface: #ffffff;
  --surface-soft: #f7f9fc;
  --ink: #17202f;
  --muted: #647084;
  --line: #dbe2ea;
  --blue: #2255a4;
  --blue-strong: #183f7f;
  --green: #13795b;
  --amber: #b66a00;
  --red: #b42318;
  --shadow: 0 18px 45px rgba(24, 38, 62, 0.12);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  min-height: 100vh;
  color: var(--ink);
  background:
    linear-gradient(135deg, rgba(34, 85, 164, 0.08), transparent 42%),
    var(--bg);
  font-family: "Segoe UI", Arial, sans-serif;
}

button,
input,
select,
textarea {
  font: inherit;
}

button {
  cursor: pointer;
}

svg {
  width: 1.1rem;
  height: 1.1rem;
  fill: none;
  stroke: currentColor;
  stroke-width: 1.9;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.app-shell {
  display: grid;
  grid-template-columns: 300px minmax(0, 1fr);
  min-height: 100vh;
}

.sidebar {
  position: sticky;
  top: 0;
  height: 100vh;
  padding: 28px;
  color: #f8fbff;
  background: #17202f;
  display: flex;
  flex-direction: column;
  gap: 32px;
}

.brand {
  display: flex;
  gap: 14px;
  align-items: center;
}

.brand-mark {
  display: grid;
  place-items: center;
  width: 48px;
  height: 48px;
  border-radius: 8px;
  color: #ffffff;
  background: var(--green);
}

.brand-mark svg {
  width: 28px;
  height: 28px;
}

.brand h1,
.brand p,
.topbar h2,
.topbar p,
.panel h3,
.panel h4 {
  margin: 0;
}

.brand h1 {
  font-size: 1.15rem;
}

.brand p {
  margin-top: 4px;
  color: #b8c3d2;
  font-size: 0.88rem;
}

.step-list {
  display: grid;
  gap: 8px;
}

.step-link {
  color: #d8e1ed;
  text-decoration: none;
  padding: 11px 12px;
  border-radius: 8px;
}

.step-link:hover,
.step-link.active {
  background: rgba(255, 255, 255, 0.12);
  color: #ffffff;
}

.status-panel {
  margin-top: auto;
  padding: 16px;
  border: 1px solid rgba(255, 255, 255, 0.18);
  border-radius: 8px;
  background: rgba(255, 255, 255, 0.08);
}

.status-label {
  color: #c8d3e1;
  font-size: 0.82rem;
}

.progress-track {
  height: 8px;
  margin: 12px 0 8px;
  overflow: hidden;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.18);
}

.progress-track span {
  display: block;
  width: 0;
  height: 100%;
  background: #4bb58f;
  transition: width 180ms ease;
}

.workspace {
  min-width: 0;
  padding: 28px;
}

.topbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 20px;
  margin-bottom: 22px;
}

.eyebrow {
  color: var(--blue);
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0;
  text-transform: uppercase;
}

.topbar h2 {
  max-width: 760px;
  margin-top: 5px;
  font-size: clamp(1.35rem, 2.2vw, 2.2rem);
  line-height: 1.12;
}

.topbar-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

.language-switcher {
  display: inline-flex;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
}

.language-button {
  min-height: 40px;
  min-width: 44px;
  border: 0;
  border-right: 1px solid var(--line);
  color: var(--muted);
  background: transparent;
  font-weight: 800;
}

.language-button:last-child {
  border-right: 0;
}

.language-button.active {
  color: #ffffff;
  background: var(--blue);
}

.flow-actions,
.report-actions {
  display: flex;
  justify-content: flex-end;
  gap: 10px;
  margin-top: 18px;
}

.report-actions {
  padding-top: 18px;
  border-top: 1px solid var(--line);
}

.hidden {
  display: none !important;
}

.api-status {
  min-height: 42px;
  display: inline-flex;
  align-items: center;
  padding: 0 12px;
  border: 1px solid var(--line);
  border-radius: 8px;
  color: var(--muted);
  background: var(--surface);
  font-size: 0.84rem;
  font-weight: 700;
}

.api-status.online {
  color: var(--green);
  background: #e7f5ef;
  border-color: #b9e2d0;
}

.api-status.warning {
  color: var(--amber);
  background: #fff6e8;
  border-color: #f1d3a3;
}

.primary-button,
.ghost-button,
.icon-button {
  min-height: 42px;
  border: 1px solid transparent;
  border-radius: 8px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  transition: transform 140ms ease, background 140ms ease, border-color 140ms ease;
}

.primary-button {
  padding: 0 18px;
  color: #ffffff;
  background: var(--blue);
}

.primary-button:hover {
  background: var(--blue-strong);
}

.ghost-button,
.icon-button {
  color: var(--ink);
  background: var(--surface);
  border-color: var(--line);
}

.ghost-button {
  padding: 0 12px;
}

.ghost-button:disabled,
.primary-button:disabled {
  cursor: not-allowed;
  opacity: 0.62;
}

.icon-button {
  width: 42px;
}

.ghost-button:hover,
.icon-button:hover {
  border-color: #b7c2d0;
  background: #f3f6fa;
}

.primary-button:active,
.ghost-button:active,
.icon-button:active {
  transform: translateY(1px);
}

.analysis-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(330px, 0.62fr);
  gap: 18px;
}

.panel {
  min-width: 0;
  padding: 22px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface);
  box-shadow: var(--shadow);
}

.wide {
  grid-column: 1 / -1;
}

.panel-heading {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 18px;
}

.panel-heading > div {
  display: flex;
  gap: 12px;
  align-items: center;
}

.section-number {
  display: inline-grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 8px;
  color: var(--blue);
  background: #e8eef8;
  font-weight: 800;
  font-size: 0.78rem;
}

.panel h3 {
  font-size: 1.1rem;
}

.panel h4 {
  margin-bottom: 12px;
  font-size: 0.98rem;
}

.badge {
  flex: 0 0 auto;
  padding: 6px 9px;
  border-radius: 999px;
  color: var(--green);
  background: #e7f5ef;
  font-size: 0.78rem;
  font-weight: 700;
}

.badge.muted {
  color: var(--muted);
  background: #eef2f6;
}

.field-grid {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 14px;
}

.field-grid.compact {
  grid-template-columns: repeat(2, minmax(0, 1fr));
}

label {
  display: grid;
  gap: 7px;
  color: var(--muted);
  font-size: 0.86rem;
  font-weight: 650;
}

input,
select,
textarea {
  width: 100%;
  min-width: 0;
  border: 1px solid #cdd6e1;
  border-radius: 8px;
  padding: 11px 12px;
  color: var(--ink);
  background: #ffffff;
  outline: none;
}

textarea {
  resize: vertical;
}

input:focus,
select:focus,
textarea:focus {
  border-color: var(--blue);
  box-shadow: 0 0 0 3px rgba(34, 85, 164, 0.14);
}

.stacked {
  margin-top: 16px;
}

.witness-list {
  display: grid;
  gap: 14px;
}

.witness-entry {
  position: relative;
  padding: 16px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--surface-soft);
}

.remove-witness {
  position: absolute;
  top: 10px;
  right: 10px;
  width: 32px;
  height: 32px;
  border: 1px solid transparent;
  border-radius: 8px;
  color: var(--muted);
  background: transparent;
}

.remove-witness:hover {
  color: var(--red);
  background: #fff0ee;
}

.questions-list {
  display: grid;
  gap: 12px;
}

.question-item {
  display: grid;
  gap: 8px;
  padding: 14px;
  border: 1px solid var(--line);
  border-left: 4px solid var(--amber);
  border-radius: 8px;
  background: #fffaf2;
}

.question-item strong {
  color: var(--ink);
}

.empty-state {
  min-height: 130px;
  display: grid;
  place-items: center;
  padding: 22px;
  border: 1px dashed #bac6d4;
  border-radius: 8px;
  color: var(--muted);
  text-align: center;
  background: var(--surface-soft);
}

.result-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: 22px;
}

.result-tabs {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-bottom: 16px;
  border-bottom: 1px solid var(--line);
}

.tab-button {
  min-height: 38px;
  padding: 0 14px;
  border: 1px solid transparent;
  border-bottom: 3px solid transparent;
  color: var(--muted);
  background: transparent;
  font-weight: 750;
}

.tab-button:hover {
  color: var(--blue);
}

.tab-button.active {
  color: var(--blue-strong);
  border-bottom-color: var(--blue);
}

.tab-panel {
  display: none;
}

.tab-panel.active {
  display: block;
}

.fault-tree {
  align-items: stretch;
  text-align: left;
}

.tree {
  display: grid;
  gap: 12px;
}

.tree-node {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.tree-node.top {
  color: #ffffff;
  background: var(--blue);
  border-color: var(--blue);
}

.tree-branches {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 1fr));
  gap: 12px;
}

.tree-branch {
  position: relative;
  display: grid;
  gap: 8px;
}

.tree-branch::before {
  content: "";
  height: 16px;
  width: 1px;
  background: #aeb9c7;
  justify-self: center;
}

.tree-node.category {
  color: var(--blue-strong);
  background: #eef4ff;
  font-weight: 750;
}

.tree-node.cause {
  min-height: 74px;
  background: #f9fbfd;
}

.bowtie-diagram,
.ishikawa-diagram,
.timeline-view,
.five-whys-view {
  align-items: stretch;
  text-align: left;
}

.timeline-list {
  display: grid;
  gap: 12px;
  counter-reset: timeline;
}

.timeline-item {
  display: grid;
  grid-template-columns: 42px minmax(0, 1fr);
  gap: 12px;
  align-items: start;
}

.timeline-item::before {
  counter-increment: timeline;
  content: counter(timeline);
  display: grid;
  place-items: center;
  width: 34px;
  height: 34px;
  border-radius: 999px;
  color: #ffffff;
  background: var(--blue);
  font-weight: 800;
}

.timeline-card,
.why-card {
  padding: 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.timeline-card strong,
.why-card strong {
  display: block;
  margin-bottom: 6px;
  color: var(--blue-strong);
}

.timeline-meta,
.why-meta {
  margin-top: 8px;
  color: var(--muted);
  font-size: 0.86rem;
}

.why-stack {
  display: grid;
  gap: 14px;
}

.why-chain {
  display: grid;
  gap: 8px;
  margin-top: 10px;
}

.why-step {
  padding: 10px 12px;
  border-left: 4px solid var(--blue);
  border-radius: 8px;
  background: #f7f9fc;
}

.bowtie-grid {
  display: grid;
  grid-template-columns: minmax(0, 1fr) minmax(220px, 0.72fr) minmax(0, 1fr);
  gap: 14px;
  align-items: stretch;
}

.bowtie-column {
  display: grid;
  gap: 10px;
}

.bowtie-node,
.fish-node,
.fish-head {
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: #ffffff;
}

.bowtie-node h5,
.fish-node h5 {
  margin: 0 0 6px;
  color: var(--blue-strong);
  font-size: 0.9rem;
}

.bowtie-node ul,
.fish-node ul {
  margin: 0;
  padding-left: 18px;
}

.bowtie-center {
  display: grid;
  align-content: center;
  justify-items: center;
  gap: 10px;
}

.bowtie-event {
  width: 100%;
  padding: 18px;
  border-radius: 8px;
  color: #ffffff;
  background: var(--blue);
  text-align: center;
  font-weight: 800;
}

.bowtie-arrow {
  color: var(--muted);
  font-weight: 800;
}

.fishbone {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 220px;
  gap: 14px;
  align-items: center;
}

.fish-spines {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 12px;
  position: relative;
}

.fish-spines::after {
  content: "";
  position: absolute;
  left: 0;
  right: 0;
  top: 50%;
  height: 2px;
  background: #aeb9c7;
  z-index: 0;
}

.fish-node {
  position: relative;
  z-index: 1;
  background: #f9fbfd;
}

.fish-head {
  color: #ffffff;
  background: var(--green);
  font-weight: 800;
  text-align: center;
}

.result-list {
  display: grid;
  gap: 10px;
  margin: 0 0 22px 0;
  padding-left: 22px;
}

.result-list li {
  padding-left: 5px;
}

.actions li::marker {
  color: var(--green);
  font-weight: 800;
}

@media (max-width: 1050px) {
  .app-shell {
    grid-template-columns: 1fr;
  }

  .sidebar {
    position: static;
    height: auto;
    padding: 18px;
  }

  .step-list {
    grid-template-columns: repeat(4, minmax(0, 1fr));
  }

  .status-panel {
    display: none;
  }

  .analysis-grid,
  .result-layout {
    grid-template-columns: 1fr;
  }

  .field-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

@media (max-width: 680px) {
  .workspace {
    padding: 16px;
  }

  .topbar {
    align-items: stretch;
    flex-direction: column;
  }

  .topbar-actions {
    justify-content: flex-end;
    flex-wrap: wrap;
  }

  .topbar-actions .api-status {
    width: 100%;
    justify-content: center;
  }

  .flow-actions,
  .report-actions {
    align-items: stretch;
    flex-direction: column;
  }

  .step-list,
  .field-grid,
  .field-grid.compact,
  .tree-branches,
  .bowtie-grid,
  .fishbone,
  .fish-spines {
    grid-template-columns: 1fr;
  }

  .panel {
    padding: 16px;
  }
}