* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, Oxygen, Ubuntu, sans-serif;
  background: #f8fafc;
  color: #1e293b;
  line-height: 1.5;
}

.container {
  max-width: 900px;
  margin: 0 auto;
  padding: 2rem;
}

header {
  margin-bottom: 1.5rem;
}

header h1 {
  margin: 0 0 0.25rem;
  font-size: 1.75rem;
  font-weight: 700;
}

.tagline {
  margin: 0;
  font-size: 0.95rem;
  color: #64748b;
}

.desc {
  margin: 0.5rem 0 0;
  font-size: 0.9rem;
  color: #475569;
}

/* Tabs */
.tabs {
  display: flex;
  gap: 0;
  margin-bottom: 1rem;
  border-bottom: 1px solid #e2e8f0;
}

.tab-btn {
  padding: 0.6rem 1.2rem;
  font-size: 0.95rem;
  font-weight: 500;
  background: none;
  border: none;
  border-bottom: 2px solid transparent;
  color: #64748b;
  cursor: pointer;
  margin-bottom: -1px;
}

.tab-btn:hover {
  color: #334155;
}

.tab-btn.active {
  color: #3b82f6;
  border-bottom-color: #3b82f6;
}

.tab-content {
  display: none;
}

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

main {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.input-section {
  background: #fff;
  border-radius: 8px;
  padding: 1rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.input-header {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  align-items: center;
  gap: 0.75rem;
  margin-bottom: 0.5rem;
}

.input-header label {
  font-weight: 500;
  font-size: 0.9rem;
}

.input-actions {
  display: flex;
  align-items: center;
  gap: 0.75rem;
}

#sample-select {
  padding: 0.35rem 0.5rem;
  font-size: 0.85rem;
  border: 1px solid #cbd5e1;
  border-radius: 4px;
  background: #fff;
}

.pred-steps {
  display: flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.85rem;
}

#pred-steps {
  width: 3.5rem;
  padding: 0.35rem;
  font-size: 0.9rem;
  border: 1px solid #cbd5e1;
  border-radius: 4px;
}

#ts-input {
  width: 100%;
  padding: 0.75rem;
  font-size: 0.9rem;
  font-family: inherit;
  border: 1px solid #e2e8f0;
  border-radius: 6px;
  resize: vertical;
  min-height: 80px;
}

#ts-input:focus {
  outline: none;
  border-color: #3b82f6;
  box-shadow: 0 0 0 2px rgba(59, 130, 246, 0.2);
}

.output-section {
  background: #fff;
  border-radius: 8px;
  padding: 1rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.forecast-display {
  margin-bottom: 1rem;
  font-size: 1rem;
}

.forecast-display .label {
  color: #64748b;
}

.forecast-display .value {
  font-weight: 600;
  color: #1e293b;
}

.forecast-display .range {
  font-size: 0.85rem;
  color: #64748b;
  margin-left: 0.25rem;
}

.loading {
  padding: 0.5rem 0;
  color: #3b82f6;
  font-size: 0.9rem;
}

.error {
  padding: 0.5rem 0;
  color: #dc2626;
  font-size: 0.9rem;
}

.chart-container {
  position: relative;
  height: 300px;
  margin: 1rem 0;
}

.download-row {
  margin-top: 1rem;
}

#download-csv {
  padding: 0.5rem 1rem;
  font-size: 0.9rem;
  background: #3b82f6;
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
}

#download-csv:hover {
  background: #2563eb;
}

#download-csv:disabled {
  background: #94a3b8;
  cursor: not-allowed;
}

/* Compare tab */
.compare-section {
  background: #fff;
  border-radius: 8px;
  padding: 1.5rem;
  box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
}

.compare-section h2 {
  margin: 0 0 0.75rem;
  font-size: 1.25rem;
}

.compare-intro {
  margin: 0 0 1.5rem;
  color: #475569;
  font-size: 0.95rem;
}

.pipeline-row {
  display: flex;
  flex-direction: column;
  gap: 2rem;
}

.pipeline-block {
  display: flex;
  flex-direction: column;
  gap: 0.75rem;
}

.pipeline-label {
  margin: 0;
  font-size: 1rem;
  font-weight: 600;
  color: #334155;
}

.pipeline {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.25rem 0;
}

.pipeline.ml-pipeline {
  font-size: 0.8rem;
}

.pipeline.chronos-pipeline {
  font-size: 1rem;
}

.pipeline .step {
  padding: 0.4rem 0.6rem;
  border: 1px solid #e2e8f0;
  border-radius: 4px;
  background: #f8fafc;
  white-space: nowrap;
}

.pipeline .step.highlight {
  background: #ecfdf5;
  border-color: #059669;
  color: #047857;
  font-weight: 600;
}

.pipeline .arrow {
  color: #94a3b8;
  font-size: 0.9em;
  padding: 0 0.2rem;
}

.pipeline.chronos-pipeline .arrow {
  font-size: 1.1em;
}

.compare-cta {
  margin: 1.5rem 0 0;
  font-size: 0.95rem;
  color: #475569;
}

.compare-cta strong {
  color: #059669;
}