/* ============================================================
   VCC Vision Screening App — Styles

   Design intent: the stimulus field itself must stay a neutral
   clinical white with black/gray optotypes (non-negotiable,
   dictated by the acuity standards themselves — see Section 6-7
   of the spec). All visual "design" personality lives in the
   operator-facing chrome: the calibration screen and the menu
   drawer, styled as a quiet instrument panel rather than a
   consumer app, with tabular monospace figures for anything
   that's a measurement (distances, acuity labels, version tag).
   ============================================================ */

@font-face {
  font-family: "OpticianSans";
  src: url("../assets/fonts/Optician-Sans.woff2") format("woff2");
  font-display: block;
}

:root {
  --panel-bg: #14171C;
  --panel-bg-raised: #1C2029;
  --panel-border: #2A2F3A;
  --accent: #2FB8AC;
  --accent-warn: #D9824B;
  --text-primary: #E8EAED;
  --text-muted: #8A93A3;
  --ui-font: "IBM Plex Sans", -apple-system, BlinkMacSystemFont, sans-serif;
  --mono-font: "IBM Plex Mono", "SF Mono", monospace;
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  font-family: var(--ui-font);
  background: #000;
  -webkit-user-select: none;
  user-select: none;
  -webkit-touch-callout: none;
}

.screen {
  position: fixed;
  inset: 0;
  width: 100%;
  height: 100%;
}
.hidden { display: none !important; }

/* ---------------- Calibration screen ---------------- */

#calibration-screen {
  background: var(--panel-bg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-primary);
}

.cal-panel {
  max-width: 560px;
  width: 90%;
  text-align: center;
}
.cal-panel h1 {
  font-size: 1.5rem;
  font-weight: 600;
  margin-bottom: 0.75rem;
}
.cal-instructions {
  color: var(--text-muted);
  line-height: 1.5;
  margin-bottom: 1.5rem;
}
.cal-guide-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  height: 120px;
  margin-bottom: 1rem;
}
.cal-guide-box {
  height: 100px;
  background: var(--accent);
  border-radius: 6px;
  width: 320px;
  transition: width 0.02s linear;
}
#cal-slider {
  width: 100%;
  margin-bottom: 1.5rem;
  accent-color: var(--accent);
}
.cal-note {
  color: var(--text-muted);
  font-size: 0.8rem;
  margin-top: 1rem;
  font-family: var(--mono-font);
}

/* ---------------- Main chart screen ---------------- */

#main-screen {
  background: #FFFFFF;
}

#stimulus-area {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #FFFFFF;
}

.stimulus-center {
  display: flex;
  align-items: center;
  justify-content: center;
}

.optotype {
  font-family: "OpticianSans", monospace;
  line-height: 1;
  white-space: pre;
}

.duochrome-wrap {
  display: flex;
  width: 100%;
  height: 100%;
}
.duochrome-half {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
}

.optotype-svg {
  display: block;
}

.optotype-row {
  display: flex;
  gap: 0.4em;
  align-items: flex-end;
  line-height: 1;
}

.optotype-stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
  /* Gap is now set per-line via inline style in JS (matching the
     exact value used in the vertical-fit budget math) rather than
     a fixed CSS em value here — see renderStackedLines/renderVerticalColumn. */
}

.optotype-column {
  display: flex;
  flex-direction: column;
  align-items: center;
  width: 100%;
}

.optotype-line-wrap {
  position: relative;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 100%;
}

.line-label {
  position: absolute;
  left: 14px;
  font-family: var(--mono-font);
  font-size: 0.85rem;
  color: #999;
}

.margin-label {
  position: absolute;
  bottom: 14px;
  left: 18px;
  font-family: var(--mono-font);
  font-size: 0.95rem;
  color: #444;
  letter-spacing: 0.02em;
}

.menu-tab {
  position: absolute;
  top: 50%;
  right: 0;
  transform: translateY(-50%);
  width: 28px;
  height: 64px;
  background: var(--panel-bg);
  color: var(--text-muted);
  border-radius: 8px 0 0 8px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.2rem;
  opacity: 0.5;
  cursor: pointer;
}

/* ---------------- Menu drawer ---------------- */

.menu-drawer {
  position: absolute;
  top: 0;
  right: 0;
  height: 100%;
  width: min(360px, 86vw);
  background: var(--panel-bg);
  color: var(--text-primary);
  transform: translateX(100%);
  transition: transform 0.22s ease;
  overflow-y: auto;
  padding: 1rem 1.1rem 2rem;
  border-left: 1px solid var(--panel-border);
}
.menu-drawer.open {
  transform: translateX(0);
}

.menu-header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  font-weight: 600;
  font-size: 1.05rem;
  margin-bottom: 1.2rem;
  padding-bottom: 0.6rem;
  border-bottom: 1px solid var(--panel-border);
}
.btn-icon {
  background: none;
  border: none;
  color: var(--text-muted);
  font-size: 1.4rem;
  cursor: pointer;
  line-height: 1;
}

.menu-section {
  margin-bottom: 1.4rem;
}
.menu-section h2 {
  font-size: 0.72rem;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-muted);
  font-weight: 600;
  margin: 0 0 0.6rem;
}

.btn-row {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}
.btn-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0.5rem;
}

.btn {
  font-family: var(--ui-font);
  border-radius: 8px;
  padding: 0.55rem 0.8rem;
  font-size: 0.88rem;
  cursor: pointer;
  border: 1px solid var(--panel-border);
  background: var(--panel-bg-raised);
  color: var(--text-primary);
}
.btn-option.selected {
  background: var(--accent);
  border-color: var(--accent);
  color: #04211E;
  font-weight: 600;
}
.btn-primary {
  background: var(--accent);
  border-color: var(--accent);
  color: #04211E;
  font-weight: 600;
  width: 100%;
  padding: 0.75rem;
  font-size: 1rem;
}
.btn-secondary {
  background: var(--panel-bg-raised);
}
.btn-warning {
  background: transparent;
  border-color: var(--accent-warn);
  color: var(--accent-warn);
}
.full-width {
  width: 100%;
  margin-bottom: 0.5rem;
}

.custom-distance-row {
  display: flex;
  gap: 0.5rem;
  margin-top: 0.6rem;
}
.custom-distance-row input {
  flex: 1;
  font-family: var(--mono-font);
  background: var(--panel-bg-raised);
  border: 1px solid var(--panel-border);
  color: var(--text-primary);
  border-radius: 8px;
  padding: 0.5rem;
}

.menu-footer {
  margin-top: 1.6rem;
  padding-top: 1rem;
  border-top: 1px solid var(--panel-border);
}
.branding-footer {
  font-size: 0.72rem;
  color: var(--text-muted);
  line-height: 1.4;
  margin: 0.8rem 0 0.4rem;
}
.version-tag {
  font-family: var(--mono-font);
  font-size: 0.7rem;
  color: var(--text-muted);
  margin: 0;
}

/* ---------------- Validation / self-test overlay ---------------- */

.overlay-screen {
  background: var(--panel-bg);
  color: var(--text-primary);
  display: flex;
  align-items: center;
  justify-content: center;
}
.validation-panel {
  width: 92%;
  max-width: 640px;
  max-height: 88vh;
  overflow-y: auto;
  background: var(--panel-bg-raised);
  border: 1px solid var(--panel-border);
  border-radius: 12px;
  padding: 1.2rem 1.4rem;
}
.validation-table {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}
.validation-row {
  display: grid;
  grid-template-columns: 70px 1fr 140px;
  align-items: center;
  gap: 0.8rem;
  padding: 0.4rem 0;
  border-bottom: 1px solid var(--panel-border);
}
.val-label {
  font-family: var(--mono-font);
  font-size: 0.85rem;
  color: var(--accent);
}
.val-optotype {
  font-family: "OpticianSans", monospace;
  color: #FFFFFF;
  line-height: 1;
}
.val-expected {
  font-family: var(--mono-font);
  font-size: 0.78rem;
  color: var(--text-muted);
  text-align: right;
}