.step-item {
  display: flex;
  align-items: flex-start;
  gap: 12px;
  padding: 10px 20px;
  cursor: pointer;
  border-left: 2px solid transparent;
  transition: all 0.15s;
}

.step-item:hover { background: var(--surface2); }

.step-item.active {
  background: var(--surface2);
  border-left-color: var(--accent);
}

.step-item.completed .step-num {
  background: var(--green);
  color: var(--bg);
}

.step-num {
  width: 24px;
  height: 24px;
  min-width: 24px;
  border-radius: 50%;
  background: var(--surface2);
  border: 1.5px solid var(--border);
  font-size: 13px;
  font-weight: 700;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--muted);
  margin-top: 1px;
}

.step-item.active .step-num {
  background: var(--accent);
  color: white;
  border-color: var(--accent);
}

.step-title { font-size: 15px; font-weight: 500; line-height: 1.4; }
.step-actor { font-size: 13px; color: var(--muted); margin-top: 2px; }

.step-header {
  margin-bottom: 24px;
}

.step-header .actor-badge {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.8px;
  text-transform: uppercase;
  padding: 3px 10px;
  border-radius: 4px;
  margin-bottom: 10px;
  display: inline-block;
}

.actor-client     { background: var(--tint-accent);  color: var(--accent); }
.actor-browser    { background: var(--tint-green);   color: var(--accent2); }
.actor-authserver { background: var(--tint-yellow);  color: var(--yellow); }
.actor-resource   { background: var(--tint-green);   color: var(--green); }

.step-header h2 { font-size: 25px; font-weight: 700; margin-bottom: 8px; }
.step-header p { font-size: 17px; color: var(--muted); line-height: 1.6; max-width: 680px; }

.section { margin-bottom: 28px; }
.section-title {
  font-size: 14px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 1px;
  color: var(--muted);
  margin-bottom: 12px;
}

.explanation-box {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  font-size: 16px;
  line-height: 1.7;
  color: var(--text);
}

.explanation-box ul {
  padding-left: 20px;
  margin-top: 8px;
}

.explanation-box li { margin-bottom: 6px; }

.highlight { color: var(--accent); font-weight: 600; }
.hl-green { color: var(--green); font-weight: 600; }
.hl-yellow { color: var(--yellow); font-weight: 600; }

/* Data exchange cards */
.data-card {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  overflow: hidden;
  margin-bottom: 12px;
}

.data-card-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 16px;
  background: var(--surface2);
  border-bottom: 1px solid var(--border);
  font-size: 14px;
  font-weight: 600;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.direction-badge {
  font-size: 13px;
  padding: 2px 8px;
  border-radius: 4px;
  font-weight: 700;
}

.dir-send     { background: var(--tint-accent);  color: var(--accent); }
.dir-receive  { background: var(--tint-green);   color: var(--green); }
.dir-generate { background: var(--tint-yellow);  color: var(--yellow); }

.data-card pre {
  padding: 16px;
  font-family: 'SF Mono', 'Fira Code', monospace;
  font-size: 12.5px;
  line-height: 1.7;
  color: var(--text);
  overflow-x: auto;
  white-space: pre;
}

.key     { color: var(--accent2); }
.val     { color: var(--green); }
.url     { color: var(--red); }
.comment { color: var(--muted); font-style: italic; }

/* diagram */
.flow-diagram {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px;
  margin-bottom: 12px;
}

.flow-diagram svg {
  display: block;
  margin: 0 auto;
}

/* Why it matters callout */
.callout {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  background: var(--tint-callout);
  border: 1px solid var(--border-callout);
  border-radius: 10px;
  padding: 16px;
  margin-top: 12px;
}

.callout-icon { font-size: 20px; margin-top: 1px; }
.callout-body { font-size: 13.5px; line-height: 1.6; }
.callout-body strong { color: var(--accent); display: block; margin-bottom: 4px; }

/* nav */
.step-nav {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-top: 36px;
  padding-top: 24px;
  border-top: 1px solid var(--border);
}

.btn {
  padding: 10px 22px;
  border-radius: 8px;
  font-size: 16px;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: all 0.15s;
}

.btn-primary {
  background: var(--accent);
  color: white;
}

.btn-primary:hover { filter: brightness(1.15); }

.btn-secondary {
  background: var(--surface2);
  color: var(--text);
  border: 1px solid var(--border);
}

.btn-secondary:hover { background: var(--border); }

.btn:disabled {
  opacity: 0.3;
  cursor: not-allowed;
}

.progress-text {
  font-size: 15px;
  color: var(--muted);
  margin-left: auto;
}

/* completion screen */
.completion {
  text-align: center;
  padding: 60px 20px;
}

.completion .big-icon { font-size: 56px; margin-bottom: 20px; }
.completion h2 { font-size: 32px; font-weight: 700; margin-bottom: 12px; }
.completion p { color: var(--muted); font-size: 17px; max-width: 480px; margin: 0 auto 28px; line-height: 1.6; }

.token-summary {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 20px 24px;
  text-align: left;
  max-width: 560px;
  margin: 0 auto 28px;
}

.token-summary h3 { font-size: 15px; font-weight: 700; color: var(--muted); text-transform: uppercase; letter-spacing: 1px; margin-bottom: 14px; }

.token-row {
  display: flex;
  align-items: flex-start;
  gap: 10px;
  margin-bottom: 10px;
  font-size: 15px;
}

.token-row-label { color: var(--muted); min-width: 140px; }
.token-row-val { font-family: monospace; color: var(--green); font-size: 14px; word-break: break-all; }

.flow-progress-wrap {
  background: var(--code-bg);
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 14px 16px 10px;
  margin-bottom: 24px;
}

.flow-progress-wrap .section-title { margin-bottom: 10px; }