/* ── Variables ─────────────────────────────────────────────────────────── */
:root {
  --bg:        #070a0e;
  --surface:   #0d1117;
  --surface2:  #111820;
  --border:    #1c2b3a;
  --border2:   #243447;
  --text:      #b8ccd8;
  --text-dim:  #3d5166;
  --amber:     #e8a838;
  --amber-dim: #7a5319;
  --cyan:      #29c9b8;

  --cat-under: #4da6ff;
  --cat-normal:#4dcc7a;
  --cat-over:  #ffaa38;
  --cat-obese: #ff5252;

  --mono: 'JetBrains Mono', monospace;
  --display: 'Bebas Neue', sans-serif;

  --radius: 2px;
}

/* ── Reset ─────────────────────────────────────────────────────────────── */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html { font-size: 16px; }

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--mono);
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
}

/* ── Scanlines overlay ─────────────────────────────────────────────────── */
.scanlines {
  pointer-events: none;
  position: fixed;
  inset: 0;
  z-index: 100;
  background: repeating-linear-gradient(
    0deg,
    transparent,
    transparent 2px,
    rgba(0,0,0,.18) 2px,
    rgba(0,0,0,.18) 4px
  );
  opacity: .35;
}

/* ── Header ────────────────────────────────────────────────────────────── */
.site-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1.25rem 2rem;
  border-bottom: 1px solid var(--border);
  background: var(--surface);
}

.logo {
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.9rem;
  letter-spacing: 0.2em;
  color: var(--text);
}
.logo span { color: var(--amber); }

.sys-status {
  display: flex;
  align-items: center;
  gap: .5rem;
  color: var(--cyan);
  font-size: 0.72rem;
  letter-spacing: 0.15em;
}

.pulse {
  width: 7px;
  height: 7px;
  background: var(--cyan);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}
@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50%       { opacity: .3; transform: scale(.7); }
}

/* ── Panel shared ──────────────────────────────────────────────────────── */
.panel {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  padding: 1.75rem;
  position: relative;
}

.panel__label {
  font-size: 0.65rem;
  letter-spacing: 0.2em;
  color: var(--text-dim);
  margin-bottom: 1.5rem;
}

/* ── Workspace (two panels side by side) ───────────────────────────────── */
.workspace {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
  padding: 1.5rem 2rem;
}

/* ── Input panel ───────────────────────────────────────────────────────── */
.panel--input { }

.field-group {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
  margin-bottom: 1.25rem;
}

.field {
  display: flex;
  flex-direction: column;
  gap: .5rem;
}

.field label {
  font-size: 0.65rem;
  letter-spacing: 0.15em;
  color: var(--text-dim);
}

.field input {
  background: var(--bg);
  border: 1px solid var(--border2);
  border-radius: var(--radius);
  color: var(--text);
  font-family: var(--mono);
  font-size: 1rem;
  font-weight: 600;
  padding: .7rem .9rem;
  width: 100%;
  transition: border-color .15s, box-shadow .15s;
  -moz-appearance: textfield;
}
.field input::-webkit-outer-spin-button,
.field input::-webkit-inner-spin-button { -webkit-appearance: none; }

.field input::placeholder { color: var(--text-dim); font-weight: 300; }
.field input:focus {
  outline: none;
  border-color: var(--amber);
  box-shadow: 0 0 0 2px rgba(232,168,56,.15);
}
.field input.is-invalid { border-color: var(--cat-obese); }

.form-error {
  font-size: 0.7rem;
  color: var(--cat-obese);
  letter-spacing: 0.1em;
  margin-bottom: .75rem;
}

#submit-btn {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  background: var(--amber);
  color: var(--bg);
  border: none;
  border-radius: var(--radius);
  font-family: var(--mono);
  font-weight: 600;
  font-size: 0.85rem;
  letter-spacing: 0.2em;
  padding: .85rem 1.25rem;
  cursor: pointer;
  transition: background .15s, transform .1s;
}
#submit-btn:hover  { background: #f0b840; }
#submit-btn:active { transform: scale(.98); }
#submit-btn:disabled { opacity: .45; cursor: not-allowed; }

.btn-arrow { font-size: 1.1rem; transition: transform .2s; }
#submit-btn:not(:disabled):hover .btn-arrow { transform: translateX(4px); }

/* ── Result panel ──────────────────────────────────────────────────────── */
.panel--result {
  display: flex;
  flex-direction: column;
}

.result-idle {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}
.idle-text {
  font-size: 1.4rem;
  letter-spacing: 0.25em;
  color: var(--text-dim);
  text-align: center;
  line-height: 1.7;
  animation: blink 2.8s step-end infinite;
}
@keyframes blink {
  0%, 80%, 100% { opacity: 1; }
  40%           { opacity: .2; }
}

.result-data { display: flex; flex-direction: column; gap: 1.25rem; }

/* BMI readout number */
.bmi-readout__label {
  font-size: 0.65rem;
  letter-spacing: 0.18em;
  color: var(--text-dim);
  margin-bottom: .25rem;
}
.bmi-readout__value {
  font-family: var(--display);
  font-size: 5.5rem;
  line-height: 1;
  color: var(--amber);
  letter-spacing: .02em;
  transition: color .3s;
}

/* Meter bar */
.bmi-meter { }

.meter-track {
  position: relative;
  height: 10px;
  border-radius: 2px;
  overflow: visible;
  display: flex;
  margin-bottom: .4rem;
}

.meter-segment {
  /* flex values are proportional to BMI range width so the marker's
     linear position (bmi - 10) / 35 maps directly to visual position */
  opacity: .35;
  transition: opacity .3s;
  border-right: 2px solid var(--bg);
}
.meter-segment:last-child { border-right: none; }
.meter-segment.active { opacity: 1; }

/* Underweight 10–18.5 = 8.5, Normal 18.5–25 = 6.5, Over 25–30 = 5, Obese 30–45 = 15 */
.seg--under  { flex: 8.5; background: var(--cat-under); }
.seg--normal { flex: 6.5; background: var(--cat-normal); }
.seg--over   { flex: 5;   background: var(--cat-over); }
.seg--obese  { flex: 15;  background: var(--cat-obese); }

.meter-marker {
  position: absolute;
  top: -4px;
  width: 4px;
  height: 18px;
  background: #fff;
  border-radius: 2px;
  transform: translateX(-50%);
  transition: left .5s cubic-bezier(.34,1.56,.64,1);
  box-shadow: 0 0 8px rgba(255,255,255,.6);
}

.meter-ticks {
  display: flex;
  justify-content: space-between;
  color: var(--text-dim);
  font-size: 0.6rem;
  letter-spacing: 0.05em;
}

/* Category badge */
.category-badge {
  display: inline-block;
  padding: .45rem 1rem;
  border-radius: var(--radius);
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.2em;
  border: 1px solid;
  width: fit-content;
  transition: background .3s, border-color .3s, color .3s;
}
.category-badge.cat--underweight { color: var(--cat-under);  border-color: var(--cat-under);  background: rgba(77,166,255,.1); }
.category-badge.cat--normal      { color: var(--cat-normal); border-color: var(--cat-normal); background: rgba(77,204,122,.1); }
.category-badge.cat--overweight  { color: var(--cat-over);   border-color: var(--cat-over);   background: rgba(255,170,56,.1); }
.category-badge.cat--obese       { color: var(--cat-obese);  border-color: var(--cat-obese);  background: rgba(255,82,82,.1);  }

.result-meta {
  font-size: 0.68rem;
  color: var(--text-dim);
  letter-spacing: 0.08em;
  border-top: 1px solid var(--border);
  padding-top: .9rem;
}

/* ── History section ───────────────────────────────────────────────────── */
.history {
  margin: 0 2rem 2rem;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.history__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 1rem 1.5rem;
  background: var(--surface);
  border-bottom: 1px solid var(--border);
}
.history__header .panel__label { margin-bottom: 0; }

.record-count {
  font-size: 0.65rem;
  letter-spacing: 0.12em;
  color: var(--text-dim);
}

.table-wrap { overflow-x: auto; }

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--surface2);
}

thead th {
  font-size: 0.62rem;
  letter-spacing: 0.16em;
  color: var(--text-dim);
  text-align: left;
  padding: .65rem 1.5rem;
  border-bottom: 1px solid var(--border);
  white-space: nowrap;
}

tbody tr {
  border-bottom: 1px solid var(--border);
  transition: background .12s;
  animation: rowIn .25s ease both;
}
tbody tr:last-child { border-bottom: none; }
tbody tr:hover { background: var(--surface); }

@keyframes rowIn {
  from { opacity: 0; transform: translateY(-4px); }
  to   { opacity: 1; transform: translateY(0); }
}

tbody td {
  padding: .7rem 1.5rem;
  font-size: 0.75rem;
  color: var(--text);
}

.empty-row td {
  text-align: center;
  color: var(--text-dim);
  letter-spacing: 0.15em;
  padding: 2rem;
}

td.cat-cell { font-weight: 600; letter-spacing: 0.1em; }
td.cat-cell.cat--underweight { color: var(--cat-under);  }
td.cat-cell.cat--normal      { color: var(--cat-normal); }
td.cat-cell.cat--overweight  { color: var(--cat-over);   }
td.cat-cell.cat--obese       { color: var(--cat-obese);  }

/* ── Responsive ────────────────────────────────────────────────────────── */
@media (max-width: 720px) {
  .workspace { grid-template-columns: 1fr; }
  .bmi-readout__value { font-size: 4rem; }
  .site-header { padding: 1rem 1.25rem; }
  .workspace,
  .history { margin-left: 1rem; margin-right: 1rem; }
  .workspace { padding: 1rem; }
}