/* ==========================================================================
  1. DESIGN SYSTEM (VARIABLES)
  - The single source of truth for all colors, fonts, spacing, etc.
  ========================================================================== */
:root {
  --font-sans:
    "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto,
    "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", "Fira Code", "JetBrains Mono", monospace;
  --font-title: "Poppins", -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;

  /* Refined Color Palette */
  --color-primary: #4a6cfd;
  --color-primary-hover: #3b57e3;
  --color-text-primary: #111827;
  --color-text-secondary: #4b5563;
  --color-text-tertiary: #6b7280;
  --color-text-on-primary: #ffffff;
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-danger: #ef4444;

  /* Background & Borders */
  --color-bg-app: #f9fafb;
  --color-bg-component: #ffffff;
  --color-bg-alt: #f3f4f6;
  --color-border: #e5e7eb;

  /* Sizing & Spacing */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1), 0 2px 4px -2px rgb(0 0 0 / 0.1);
}

/* ==========================================================================
  2. GLOBAL STYLES & RESETS
  ========================================================================== */
*,
*::before,
*::after {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background-color: var(--color-bg-app);
  color: var(--color-text-primary);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* ==========================================================================
  3. MAIN APP LAYOUT & STRUCTURE
  ========================================================================== */
.app-layout {
  display: grid;
  grid-template-columns: 320px 1fr;
  gap: var(--spacing-lg);
  padding: var(--spacing-lg);
  align-items: start;
  max-width: 1600px;
  margin: 0 auto;
}

/* --- Header (CORRECTED) --- */
/* This rule is now clean and free of conflicts. */
.header {
  grid-column: 1 / -1;
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--spacing-lg);
  background-color: var(--color-bg-component);
  padding: .95em;
  box-shadow: var(--shadow-sm);
  text-align: center;
}
.header__title {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.02em;
}
.header__subtitle {
  font-weight: 500;
  color: var(--color-text-secondary);
}
.header__desc {
  margin-top: var(--spacing-sm);
  font-size: 1rem;
  color: var(--color-text-secondary);
}

/* --- Sidebar --- */
.sidebar {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}

/* ...existing code... */

.sidebar-expander {
  margin-top: 2rem;
  border-radius: var(--radius-md);
  background: var(--color-bg-alt);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-sm) var(--spacing-md);
}

.sidebar-expander__toggle {
  width: 100%;
  background: none;
  border: none;
  font-family: var(--font-title);

  font-weight: 600;
  color: #0d66ff;
  display: flex;
  align-items: center;
  justify-content: space-between;
  cursor: pointer;
  padding: var(--spacing-xs) 0;
  transition: color 0.18s;
}

.sidebar-expander__toggle:hover,
.sidebar-expander__toggle:focus {
  color: #084ec4;
}

.sidebar-expander__icon {
  font-size: 1.1rem;
  margin-left: 0.5rem;
  transition: transform 0.2s;
}
.sidebar-title {
  font-size: 1.1rem;
  transition: transform 0.2s;
}
.sidebar-expander__icon.expanded {
  transform: rotate(180deg);
}

.sidebar-expander__panel {
  margin-top: var(--spacing-sm);
  font-size: 0.98rem;
  color: var(--color-text-secondary);
  background: none;
  border-radius: var(--radius-sm);
  padding: 0.2rem 0.1rem;
  line-height: 1.6;
}

/* ==========================================================================
  4. SHARED COMPONENT STYLES
  ========================================================================== */

/* --- Generic Card --- */
.card {
  background-color: var(--color-bg-component);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  padding: var(--spacing-lg);
}
.card__title {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 0 0 var(--spacing-md) 0;
  padding-bottom: var(--spacing-md);
  border-bottom: 1px solid var(--color-border);
}
.card__subtitle {
  font-size: 1rem;
  color: var(--color-text-secondary);
  margin: calc(-1 * var(--spacing-sm)) 0 var(--spacing-md) 0;
  line-height: 1.5;
}

/* --- Tabs --- */
.tabs {
  display: flex;
  gap: var(--spacing-sm);
  border-bottom: 1px solid var(--color-border);
  margin-bottom: var(--spacing-lg);
}
.tab {
  padding: var(--spacing-sm) var(--spacing-md);
  border: none;
  background: none;
  cursor: pointer;
  font-size: 1rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  border-bottom: 2px solid transparent;
  transform: translateY(1px);
}
.tab.active,
.tab:hover {
  color: var(--color-primary);
}
.tab.active {
  border-bottom-color: var(--color-primary);
}
.tab-content {
  padding-top: var(--spacing-md);
}

/* --- Forms & Buttons --- */
.form-group {
  margin-bottom: var(--spacing-md);
}
.form-label {
  display: block;
  font-weight: 500;
  margin-bottom: var(--spacing-sm);
  font-size: 0.875rem;
}
.form-select {
  width: 100%;
  padding: var(--spacing-sm) var(--spacing-md);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  background-color: var(--color-bg-component);
  font-family: var(--font-sans);
  font-size: 1rem;
  box-shadow: var(--shadow-sm);
}
.button-group {
  display: flex;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
}
.btn {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 0.95rem;
  border-radius: var(--radius-md);
  padding: 0.6rem 1.2rem;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s ease;
}
.btn--primary {
  background-color: var(--color-primary);
  color: var(--color-text-on-primary);
  box-shadow: var(--shadow-sm);
}
.btn--primary:hover {
  background-color: var(--color-primary-hover);
}
.btn--secondary {
  background-color: var(--color-bg-component);
  border-color: var(--color-border);
  color: var(--color-text-secondary);
  box-shadow: var(--shadow-sm);
}
.btn--secondary:hover {
  border-color: #d1d5db;
}
.btn:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

/* --- Status Indicators (Loading, Error, etc.) --- */
.loading-indicator {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md);
  font-size: 0.9rem;
}
.spinner {
  width: 18px;
  height: 18px;
  border-radius: 50%;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  animation: spin 1s linear infinite;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}
.error-message {
  padding: var(--spacing-md);
  margin-top: var(--spacing-md);
  background-color: #fee2e2;
  color: #991b1b;
  border-radius: var(--radius-md);
  font-weight: 500;
}
.status-ok {
  color: var(--color-success);
}
.status-bad {
  color: var(--color-danger);
}

/* --- Model Info Callouts (Used in Sidebar, Perf. Tracking) --- */
.model-info__callout {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-primary);
}
.model-info__callout h4 {
  font-size: 0.875rem;
  font-weight: 600;
  margin: 0 0 var(--spacing-xs) 0;
}
.model-info__callout p {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin: 0;
}
.publication-link {
  display: inline-block;
  margin-top: var(--spacing-sm);
  font-size: 0.9rem;
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 600;
}
.publication-link:hover {
  text-decoration: underline;
}

/* ==========================================================================
  5. PAGE-SPECIFIC LAYOUTS & COMPONENTS
   ========================================================================== */

/* --- Standard Analysis Page --- */
.analysis-layout {
  display: grid;
  grid-template-columns: 1fr; /* Default to single column for mobile */
  gap: var(--spacing-lg);
}

/* On screens wider than 768px, switch to a two-column layout */
@media (min-width: 768px) {
  .analysis-layout {
    /* Controls on the left (2 parts), results on the right (3 parts) */
    grid-template-columns: 2fr 3fr;
    align-items: start;
  }
}
.analysis-column {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}
.chart-container {
  height: 350px;
  width: 100%;
  margin-bottom: var(--spacing-lg);
}
/* Dropzone/File Upload Elements */
.dropzone {
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--spacing-xl);
  text-align: center;
  cursor: pointer;
  background-color: var(--color-bg-alt);
  transition:
    background-color 0.2s ease,
    border-color 0.2s ease;
}
.dropzone--active,
.dropzone:hover {
  border-color: var(--color-primary);
  background-color: #eef2ff;
}
.dropzone-content {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--spacing-xs);
}
.dropzone-icon {
  font-size: 2rem;
  margin-bottom: var(--spacing-sm);
}
.dropzone__text {
  font-weight: 500;
  margin: 0;
  color: var(--color-text-primary);
}
.dropzone__subtext {
  font-size: 0.875rem;
  color: var(--color-text-tertiary);
  margin: 0;
}
/* ...existing code... */
.dropzone-tooltip {
  display: none;
  position: absolute;
  left: 100%;
  top: 0;
  margin-left: 1rem;
  background: #f5f8fa;
  color: #123249;
  border: 1px solid #e6eef8;
  border-radius: 6px;
  padding: 0.5rem 0.8rem;
  font-size: 0.95rem;
  box-shadow: 0 2px 8px rgba(13,102,255,0.07);
  z-index: 10;
  width: 220px;
}

.dropzone:focus .dropzone-tooltip,
.dropzone:hover .dropzone-tooltip {
  display: block;
}
/* ...existing code... */

.sample-data-prompt {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--spacing-sm);
  margin-top: var(--spacing-md);
  padding: var(--spacing-sm);
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-md);
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}
.sample-data-link {
  color: var(--color-primary);
  font-weight: 500;
  text-decoration: none;
  border-radius: var(--radius-sm);
  padding: var(--spacing-xs) var(--spacing-sm);
  transition: background-color 0.2s ease;
}
.sample-data-link:hover {
  background-color: #eef2ff;
  text-decoration: underline;
}
.spectrum-info {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: #eef2ff;
  border: 1px solid #c7d2fe;
  color: #3730a3;
  border-radius: var(--radius-md);
  font-size: 0.9rem;
}
.spectrum-info p {
  margin: 0 0 var(--spacing-xs) 0;
}
.placeholder {
  display: flex;
  align-items: center;
  justify-content: center;
  min-height: 200px;
  color: var(--color-text-tertiary);
  border: 2px dashed var(--color-border);
  border-radius: var(--radius-lg);
  text-align: center;
  padding: var(--spacing-md);
}

/* --- Results Display Component --- */
.results-wrapper {
  padding-top: var(--spacing-lg);
}
.results-header {
  border-bottom: 1px solid var(--color-border);
  padding-bottom: var(--spacing-md);
}
.confidence-display__label {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
}
.confidence-display__value {
  font-size: 3rem;
  font-weight: 700;
  color: var(--color-primary);
  line-height: 1.1;
  letter-spacing: -0.025em;
}
.confidence-bar {
  width: 100%;
  height: 8px;
  background-color: var(--color-bg-alt);
  border-radius: 4px;
  overflow: hidden;
  margin: var(--spacing-md) 0;
}
.confidence-bar__fill {
  height: 100%;
  background-color: var(--color-primary);
  border-radius: 4px;
  transition: width 0.4s ease;
}
.probabilities {
  display: flex;
  gap: var(--spacing-lg);
}
.prob-item__label {
  font-size: 0.9rem;
  color: var(--color-text-secondary);
  margin-right: var(--spacing-sm);
}
.prob-item__value {
  font-weight: 500;
}
.results-grid-container {
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  margin-top: var(--spacing-lg);
}
.results-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
}
.results-card {
  background-color: var(--color-bg-component);
  border-radius: var(--radius-md);
  padding: var(--spacing-md);
  border: 1px solid var(--color-border);
}
.results-card__title {
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--color-text-secondary);
  margin: 0 0 var(--spacing-sm) 0;
  text-transform: uppercase;
  letter-spacing: 0.05em;
}
.results-card__list {
  list-style: none;
  padding: 0;
  margin: 0;
  font-size: 0.9rem;
}
.results-card__list li {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-sm) 0;
  border-bottom: 1px solid var(--color-border);
}
.results-card__list li:last-child {
  border-bottom: none;
}
.results-card__list span:first-child {
  color: var(--color-text-secondary);
}
.results-card__list span:last-child {
  font-weight: 500;
  font-family: var(--font-mono);
}
.qc-ok {
  color: var(--color-success);
}
.qc-issue {
  color: var(--color-danger);
}
.results-issues {
  margin-top: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: #fffbeb;
  border-radius: var(--radius-md);
  border-left: 3px solid var(--color-warning);
}
.results-issues h5 {
  color: #b45309;
  font-size: 0.875rem;
  margin: 0 0 var(--spacing-xs) 0;
}
.results-issues ul {
  margin: 0;
  padding-left: var(--spacing-md);
  font-size: 0.9rem;
  color: #78350f;
}

/* --- Explainability Panel --- */
.explanation-layout {
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--spacing-lg);
  margin-top: var(--spacing-lg);
}
.prediction-summary-content {
  text-align: center;
}
.prediction-badge {
  display: inline-block;
  padding: var(--spacing-sm) var(--spacing-lg);
  font-size: 1.5rem;
  font-weight: 700;
  letter-spacing: 0.05em;
  border-radius: var(--radius-md);
  color: var(--color-text-on-primary);
  margin-bottom: var(--spacing-xs);
  text-transform: uppercase;
}
.prediction-badge.stable {
  background-color: var(--color-primary);
}
.prediction-badge.weathered {
  background-color: var(--color-danger);
}
.confidence-score {
  font-size: 1.1rem;
  color: var(--color-text-secondary);
  font-weight: 500;
  margin-bottom: var(--spacing-lg);
}
.probability-breakdown {
  text-align: left;
  margin-top: var(--spacing-lg);
  border-top: 1px solid var(--color-border);
  padding-top: var(--spacing-lg);
}
.probability-item {
  display: grid;
  grid-template-columns: 80px 1fr 50px;
  align-items: center;
  gap: var(--spacing-sm);
  margin-bottom: var(--spacing-sm);
  font-size: 0.9rem;
}
.class-label {
  font-weight: 500;
  text-transform: capitalize;
}
.probability-bar {
  height: 12px;
  background-color: var(--color-bg-alt);
  border-radius: 6px;
  overflow: hidden;
}
.probability-fill {
  height: 100%;
  border-radius: 6px;
  transition: width 0.3s ease-in-out;
}
.probability-fill.stable {
  background-color: var(--color-primary);
}
.probability-fill.weathered {
  background-color: var(--color-danger);
}
.probability-value {
  font-family: var(--font-mono);
  font-weight: 500;
  text-align: right;
}
.model-info-footer {
  margin-top: var(--spacing-md);
  font-size: 0.8rem;
  color: var(--color-text-tertiary);
  text-align: center;
}
.importance-summary {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  padding: var(--spacing-md);
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-md);
  margin-bottom: var(--spacing-lg);
}
.summary-item label {
  display: block;
  font-size: 0.8rem;
  color: var(--color-text-secondary);
  font-weight: 500;
}
.summary-item span {
  font-size: 1rem;
  font-weight: 600;
  font-family: var(--font-mono);
  text-transform: capitalize;
}
.top-features-title {
  font-size: 1rem;
  font-weight: 600;
  margin: var(--spacing-lg) 0 var(--spacing-sm) 0;
}
.features-grid {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-sm);
}
.feature-item {
  display: grid;
  grid-template-columns: 60px 1fr 50px;
  align-items: center;
  gap: var(--spacing-md);
  font-size: 0.9rem;
}
.feature-index {
  font-family: var(--font-mono);
  color: var(--color-text-secondary);
  background-color: var(--color-bg-alt);
  padding: var(--spacing-xs);
  border-radius: var(--radius-sm);
  text-align: center;
}
.importance-bar {
  height: 16px;
  background-color: var(--color-bg-alt);
  border-radius: 8px;
  overflow: hidden;
}
.importance-fill {
  height: 100%;
  background-color: var(--color-primary);
  border-radius: 8px;
  transition: width 0.3s ease-in-out;
}
.importance-value {
  font-family: var(--font-mono);
  font-weight: 500;
  text-align: right;
}
.interpretation-guide {
  margin-top: var(--spacing-lg);
}
.interpretation-guide ul {
  margin: 0;
  padding-left: var(--spacing-md);
  font-size: 0.9rem;
}
.interpretation-guide li {
  margin-bottom: var(--spacing-xs);
}
.interpretation-guide li::marker {
  color: var(--color-primary);
}

/* --- Performance Tracking Panel --- */
.performance-panel {
  display: flex;
  flex-direction: column;
  gap: var(--spacing-lg);
}
.info-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--spacing-md);
}
.info-item {
  background-color: var(--color-bg-alt);
  border-radius: var(--radius-md);
  padding: var(--spacing-sm) var(--spacing-md);
}
.info-item label {
  display: block;
  font-size: 0.875rem;
  color: var(--color-text-secondary);
  font-weight: 500;
  margin-bottom: var(--spacing-xs);
}
.info-item span {
  font-size: 1.1rem;
  font-weight: 600;
  font-family: var(--font-mono);
}
.model-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-md);
}
.model-card {
  background-color: var(--color-bg-component);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-md);
  box-shadow: var(--shadow-sm);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}
.model-card__title {
  font-size: 1.1rem;
  font-weight: 600;
  margin: 0;
  padding-bottom: var(--spacing-sm);
  border-bottom: 1px solid var(--color-border);
}
.model-card__metrics {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-sm) var(--spacing-md);
  font-size: 0.9rem;
}
.model-card__metrics div {
  display: flex;
  justify-content: space-between;
  align-items: center;
}
.model-card__metrics span:first-child {
  color: var(--color-text-secondary);
  font-weight: 500;
}
.model-card__metrics span:last-child {
  font-weight: 600;
  font-family: var(--font-mono);
}
.model-info__title {
  font-size: 1rem;
  font-weight: 600;
}
.model-info__meta-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-md);
  margin-top: var(--spacing-md);
}
.meta-item {
  background-color: var(--color-bg-app);
  border-radius: var(--radius-md);
  padding: var(--spacing-sm) var(--spacing-md);
  text-align: center;
}
.meta-item__label {
  font-size: 0.8rem;
  font-weight: 500;
  color: var(--color-text-secondary);
}
.meta-item__value {
  display: block;
  font-size: 1.1rem;
  font-weight: 600;
}

/* ==========================================================================
  6. RESPONSIVE MEDIA QUERIES
   ========================================================================== */
@media (max-width: 1024px) {
  .app-layout,
  .explanation-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .analysis-layout {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 600px) {
  .results-grid {
    grid-template-columns: 1fr;
  }
}