frontend/src/index.css

/* ============================================================
   Design tokens
   ============================================================ */
:root {
  /* Surfaces */
  --bg: #fbfbfd;            /* soft cool off-white page background */
  --surface: #ffffff;       /* cards, tables */
  --surface-warm: #f7f8fc;  /* chart panel, subtle fills, row hover */

  /* Ink */
  --ink: #1b1d24;           /* headings + primary text (slate-ink) */
  --ink-muted: #5e626e;     /* subtitles, secondary */
  --ink-subtle: #9296a1;    /* tertiary labels */

  /* Accent — indigo, used sparingly */
  --accent: #4350c4;
  --accent-hover: #343fa0;
  --accent-wash: rgba(67, 80, 196, 0.08);

  /* Lines */
  --border: #e5e6ec;        /* structural borders, card edges */
  --border-strong: #d4d6de;
  --hairline: #eff0f4;      /* faint inner row separators */

  /* Warmed, ivory-friendly table accents (replace blue/green/orange) */
  --tbl-model-border: #d7daec; --tbl-model-head: #eef0f8;  /* soft periwinkle */
  --tbl-lang-border:  #cde3cd; --tbl-lang-head:  #eff6ee;  /* soft sage */
  --tbl-data-border:  #ecd9c5; --tbl-data-head:  #faf2e9;  /* soft sand */

  /* Soft, warm-tinted shadows */
  --shadow-sm: 0 1px 2px rgba(40, 33, 28, 0.05);
  --shadow-md: 0 6px 20px rgba(40, 33, 28, 0.07);

  /* Radius */
  --radius: 12px;
  --radius-sm: 8px;

  /* Type */
  --font-serif: ui-serif, Georgia, Cambria, 'Times New Roman', Times, serif; /* clean system serif, headings */
  --font-sans: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Roboto', 'Oxygen',
    'Ubuntu', 'Cantarell', 'Fira Sans', 'Droid Sans', 'Helvetica Neue', sans-serif;
  --font-mono: source-code-pro, Menlo, Monaco, Consolas, 'Courier New', monospace;
}

/* ============================================================
   Base
   ============================================================ */
body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--ink);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

code {
  font-family: var(--font-mono);
}

html, body, #root {
  height: 100%;
}

a {
  color: var(--accent);
  text-decoration: none;
  transition: color 0.15s ease;
}

a:hover {
  color: var(--accent-hover);
  text-decoration: underline;
}

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

/* Serif display headline (hero) */
.hero-title {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: clamp(2.25rem, 4vw, 2.75rem);
  line-height: 1.12;
  letter-spacing: -0.02em;
  color: var(--ink);
  margin: 1.25rem 0 0.75rem 0;
}

/* ============================================================
   Buttons (replace inline gradients + JS hover handlers)
   ============================================================ */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.7rem 1.4rem;
  border-radius: 10px;
  font-family: var(--font-sans);
  font-size: 0.95rem;
  font-weight: 500;
  line-height: 1;
  cursor: pointer;
  border: 1px solid transparent;
  transition: background-color 0.15s ease, border-color 0.15s ease,
    color 0.15s ease;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: var(--shadow-sm);
}

.btn-primary:hover {
  background: var(--accent-hover);
  color: #fff;
}

.btn-secondary {
  background: transparent;
  color: var(--ink);
  border-color: var(--border-strong);
}

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

/* Quiet ghost link (top-right GitHub) */
.ghost-link {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 0.9rem;
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
  font-weight: 500;
  color: var(--ink-muted);
  background: var(--surface);
  border: 1px solid var(--border);
  transition: background-color 0.15s ease, color 0.15s ease,
    border-color 0.15s ease;
}

.ghost-link:hover {
  background: var(--accent-wash);
  border-color: var(--accent);
  color: var(--accent-hover);
  text-decoration: none;
}

/* ============================================================
   PrimeReact base tweaks
   ============================================================ */
.p-component, .pi {
  font-size: 0.8rem;
}

.p-icon {
  width: 0.8rem;
  height: 0.8rem;
}

.p-datatable-wrapper {
  scrollbar-color: var(--border) transparent;
  border-radius: 0 0 6px 6px;
}

.p-datatable .p-datatable-tbody > tr {
  transition: background-color 0.2s ease;
}

.p-datatable .p-datatable-tbody > tr:hover {
  background-color: var(--surface-warm) !important;
}

.p-datatable .p-datatable-thead > tr > th {
  border-bottom: 1px solid var(--border);
  background-color: var(--surface-warm);
  font-weight: 500;
  color: var(--ink-muted);
  padding: 0.75rem 1rem;
}

.p-datatable .p-datatable-tbody > tr > td {
  padding: 0.75rem 1rem;
  border-bottom: 1px solid var(--hairline);
}

/* ============================================================
   Table cards — IDs keep specificity over the PrimeReact theme
   ============================================================ */
#model-table, #language-table, #dataset-table {
  border-radius: var(--radius-sm);
  box-shadow: var(--shadow-sm);
  background: var(--surface);
}

#model-table { border: 1px solid var(--tbl-model-border); }
#language-table { border: 1px solid var(--tbl-lang-border); }
#dataset-table { border: 1px solid var(--tbl-data-border); }

#model-table .p-datatable-header,
#language-table .p-datatable-header,
#dataset-table .p-datatable-header {
  border-top-width: 0;
  border-radius: 6px 6px 0 0;
  color: var(--ink);
  padding: 1rem 1.25rem;
  font-weight: 500;
}

#model-table .p-datatable-header {
  background: var(--tbl-model-head);
  border-bottom: 1px solid var(--tbl-model-border);
}

#language-table .p-datatable-header {
  background: var(--tbl-lang-head);
  border-bottom: 1px solid var(--tbl-lang-border);
}

#dataset-table .p-datatable-header {
  background: var(--tbl-data-head);
  border-bottom: 1px solid var(--tbl-data-border);
}

/* Chart panel */
#figure {
  width: 100%;
  min-width: 600px;
  height: auto;
  min-height: 700px;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1rem 1rem 1.5rem;
  background: var(--surface-warm);
  box-shadow: var(--shadow-md);
  font-family: var(--font-sans);
}

/* Legacy PrimeReact autocomplete input — soften the dated hard shadow */
.p-autocomplete-input {
  width: max(100%, 40vw);
  margin-top: 2vh;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-sm);
}

/* Carousel indicators */
.p-carousel-indicators button.p-link {
  border-radius: 999px;
  width: 8px;
  height: 8px;
  background-color: var(--border-strong);
}

.p-carousel-indicators .p-carousel-indicator.p-highlight button.p-link {
  background-color: var(--accent);
}

/* ============================================================
   PrimeReact accent harmonization (cyan -> clay).
   index.css is imported AFTER theme.css (see index.js), so these
   equal-specificity rules win without !important.
   ============================================================ */
.p-checkbox .p-checkbox-box.p-highlight {
  background: var(--accent);
  border-color: var(--accent);
}

.p-checkbox .p-checkbox-box.p-highlight:hover {
  background: var(--accent-hover);
  border-color: var(--accent-hover);
}

.p-radiobutton .p-radiobutton-box.p-highlight {
  background: var(--accent);
  border-color: var(--accent);
}

.p-slider .p-slider-range {
  background: var(--accent);
}

.p-slider .p-slider-handle {
  border-color: var(--accent);
}

.p-slider .p-slider-handle:hover {
  background: var(--accent);
}

.p-multiselect-panel .p-multiselect-items .p-multiselect-item.p-highlight,
.p-dropdown-panel .p-dropdown-items .p-dropdown-item.p-highlight {
  background: var(--accent-wash);
  color: var(--accent-hover);
}

.p-multiselect .p-multiselect-token {
  background: var(--accent-wash);
  color: var(--accent-hover);
}

.p-datatable .p-datatable-tbody > tr.p-highlight {
  background: var(--accent-wash);
  color: var(--ink);
}

.p-inputtext:enabled:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 2px var(--accent-wash);
}

/* ============================================================
   Dialogs — cohesive with the hero (serif headings, clean chrome)
   ============================================================ */
.p-dialog {
  border-radius: var(--radius);
  border: 1px solid var(--border);
  box-shadow: var(--shadow-md);
  overflow: hidden;
}

.p-dialog .p-dialog-header {
  background: var(--surface);
  border-bottom: 1px solid var(--border);
  padding: 1.25rem 1.5rem;
}

.p-dialog .p-dialog-header .p-dialog-title {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1.3rem;
  letter-spacing: -0.01em;
  color: var(--ink);
}

.p-dialog .p-dialog-content {
  padding: 0 1.5rem 1.5rem;
  color: var(--ink);
}

.p-dialog .p-dialog-content h4 {
  font-family: var(--font-sans);
  font-weight: 600;
  font-size: 1.05rem;
  color: var(--ink);
  margin: 1.6rem 0 0.5rem;
}

.p-dialog .p-dialog-content p,
.p-dialog .p-dialog-content li {
  color: var(--ink-muted);
  line-height: 1.6;
}