/* ====================================================================
   ARITHMETIC GAME — arithmetic.css
   Loaded only on arithmetic.html; depends on style.css variables.
   ==================================================================== */

body {
  display: flex;
  flex-direction: column;
  min-height: 100vh;
}

/* ---- Screen switching ------------------------------------------------ */
.game-screen        { display: none; }
.game-screen.active { flex: 1; display: flex; flex-direction: column; }

/* ---- Colour helpers not in style.css --------------------------------- */
.dn { color: var(--red); }

/* ====================================================================
   SETUP SCREEN — canvas layout mirrors index.html
   ==================================================================== */

/* The canvas fills the remaining viewport directly below the topbar.
   Override the min-height from style.css so it doesn't over-extend. */
#screen-setup .canvas {
  height: calc(100vh - 50px);
  min-height: 700px;
}

/* Per-window widths — positions are set by layoutGameWindows() in JS */
.w-arith-play      { width: 26%; min-width: 300px; }
.w-arith-analytics { width: 26%; min-width: 230px; }
.w-arith-about     { width: 22%; min-width: 200px; }

/* ---- Badge in play window bar --------------------------------------- */
.ag-badge {
  font-size: 9px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--blue);
  background: color-mix(in srgb, var(--blue) 14%, transparent);
  border: 1px solid color-mix(in srgb, var(--blue) 32%, transparent);
  border-radius: 3px;
  padding: 1px 6px;
}

/* ---- Settings form (inside play window body) ------------------------ */
.setup-desc {
  font-size: 12px;
  color: var(--text-dim);
  line-height: 1.75;
  margin-bottom: 14px;
}

.ops-section {
  border: 1px solid var(--border);
  border-radius: 5px;
  margin-bottom: 13px;
  overflow: hidden;
}

.op-row {
  padding: 8px 12px;
  border-bottom: 1px solid var(--border-dim);
}
.op-row:last-child { border-bottom: none; }

.op-label {
  display: flex;
  align-items: center;
  gap: 8px;
  cursor: pointer;
  font-size: 13px;
  user-select: none;
  margin-bottom: 3px;
}
.op-label input[type="checkbox"] {
  width: 13px;
  height: 13px;
  accent-color: var(--blue);
  cursor: pointer;
  flex-shrink: 0;
}

.op-detail {
  margin-left: 21px;
  font-size: 12px;
  color: var(--text-dim);
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 4px 5px;
}
.op-note { font-style: italic; }

.range-label { flex-shrink: 0; }

.range-group {
  display: inline-flex;
  align-items: center;
  gap: 4px;
}
.range-group input[type="number"] {
  width: 46px;
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 3px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 12px;
  padding: 2px 4px;
  text-align: center;
  -moz-appearance: textfield;
  appearance: textfield;
}
.range-group input[type="number"]:focus { outline: none; border-color: var(--blue); }
.range-group input[type="number"]::-webkit-inner-spin-button,
.range-group input[type="number"]::-webkit-outer-spin-button { -webkit-appearance: none; }

.range-sym { font-weight: bold; color: var(--text); }

.duration-row {
  display: flex;
  align-items: center;
  gap: 10px;
  font-size: 13px;
  margin-bottom: 14px;
}

.dur-select {
  background: var(--bg);
  border: 1px solid var(--border);
  border-radius: 3px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 12px;
  padding: 4px 8px;
  cursor: pointer;
}
.dur-select:focus { outline: none; border-color: var(--blue); }

.setup-foot { display: flex; justify-content: flex-end; }

/* ---- Shared button component ---------------------------------------- */
.ag-btn {
  background: transparent;
  border: 1px solid var(--border);
  border-radius: 4px;
  color: var(--text);
  font-family: var(--mono);
  font-size: 12px;
  padding: 6px 14px;
  cursor: pointer;
  transition: background 0.12s, border-color 0.12s, color 0.12s;
}
.ag-btn:hover { background: var(--blue); border-color: var(--blue); color: #fff; }
.ag-btn--primary { border-color: var(--blue); color: var(--blue); }
.ag-btn--sm      { font-size: 11px; padding: 4px 10px; }
.ag-btn--danger  { border-color: var(--red); color: var(--red); }
.ag-btn--danger:hover { background: var(--red); border-color: var(--red); color: #fff; }

/* ---- Analytics window ----------------------------------------------- */
.analytics-summary {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: 4px;
  overflow: hidden;
  margin-bottom: 12px;
}

.analytics-stat {
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 10px 6px;
  background: var(--panel);
}

.analytics-val {
  font-size: 20px;
  font-weight: bold;
  line-height: 1;
  margin-bottom: 3px;
  color: var(--text);
}

.analytics-key {
  font-size: 8.5px;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  color: var(--text-dim);
  text-align: center;
}

.a-chart-wrap {
  height: 150px;
  margin-bottom: 12px;
}
.a-chart-wrap:last-child { margin-bottom: 0; }

.analytics-empty {
  font-size: 12px;
  color: var(--text-dim);
  text-align: center;
  padding: 20px 10px;
  line-height: 1.6;
}

.analytics-foot { margin-top: 10px; display: flex; justify-content: flex-end; }

/* ---- About window --------------------------------------------------- */
.about-section { margin-bottom: 14px; }
.about-section:last-child { margin-bottom: 0; }

.about-heading {
  font-size: 9.5px;
  text-transform: uppercase;
  letter-spacing: 0.1em;
  color: var(--text-dim);
  margin-bottom: 6px;
  padding-bottom: 4px;
  border-bottom: 1px solid var(--border-dim);
}

.about-section p { font-size: 12px; color: var(--text-dim); line-height: 1.75; }
.about-section strong { color: var(--text); }

.about-section code {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--blue);
  background: color-mix(in srgb, var(--blue) 10%, transparent);
  border-radius: 3px;
  padding: 1px 4px;
}

kbd {
  font-family: var(--mono);
  font-size: 11px;
  color: var(--text);
  background: var(--bar);
  border: 1px solid var(--border);
  border-radius: 3px;
  padding: 1px 5px;
  box-shadow: 0 1px 0 var(--border);
}

/* ====================================================================
   GAME SCREEN
   ==================================================================== */
#screen-game.active { flex-direction: column; }

.game-hud {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 10px 22px;
  background: var(--bar);
  border-bottom: 1px solid var(--border);
  flex-shrink: 0;
}

.hud-item { display: flex; flex-direction: column; align-items: flex-start; min-width: 76px; }
.hud-item--right { align-items: flex-end; }

.hud-label {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--text-dim);
}

.hud-val   { font-size: 20px; color: var(--text); line-height: 1.2; }
.hud-green { color: var(--green); }

.hud-timer {
  font-size: clamp(26px, 5vw, 34px);
  font-weight: bold;
  letter-spacing: 3px;
  font-variant-numeric: tabular-nums;
  color: var(--text);
  transition: color 0.3s;
}
.hud-timer.t-amber { color: var(--amber); }
.hud-timer.t-red   { color: var(--red); animation: blink 0.5s ease-in-out infinite alternate; }

@keyframes blink { from { opacity: 1; } to { opacity: 0.4; } }

.question-area {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 2px;
  padding: 24px 20px;
}

.question-text {
  font-size: clamp(52px, 12vw, 92px);
  font-weight: bold;
  color: var(--text);
  letter-spacing: -1px;
  line-height: 1;
  text-align: center;
}

.question-eq { font-size: clamp(22px, 5vw, 38px); color: var(--text-dim); margin-bottom: 20px; }

.answer-input {
  width: clamp(150px, 28vw, 210px);
  background: var(--bg);
  border: 2px solid var(--border);
  border-radius: 5px;
  color: var(--text);
  font-family: var(--mono);
  font-size: clamp(22px, 4vw, 30px);
  padding: 10px 12px;
  text-align: center;
  outline: none;
  transition: border-color 0.12s;
  -moz-appearance: textfield;
  appearance: textfield;
}
.answer-input::-webkit-inner-spin-button,
.answer-input::-webkit-outer-spin-button { -webkit-appearance: none; }
.answer-input:focus { border-color: var(--blue); }

.feedback { height: 36px; line-height: 36px; font-size: 30px; text-align: center; margin-top: 6px; }
.fb-ok  { color: var(--green); }
.fb-err { color: var(--red); }

/* ====================================================================
   RESULTS SCREEN
   ==================================================================== */
#screen-results.active { padding: 0 16px 60px; overflow-y: auto; }

.results-wrap { max-width: 680px; margin: 0 auto; width: 100%; }

.results-topbar {
  display: flex;
  align-items: center;
  background: var(--bar);
  border: 1px solid var(--border);
  border-top: none;
  border-radius: 0 0 7px 7px;
  padding: 10px 14px;
  margin-bottom: 22px;
  gap: 10px;
}

.results-actions { margin-left: auto; display: flex; gap: 8px; }

.score-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--border);
  border: 1px solid var(--border);
  border-radius: 5px;
  overflow: hidden;
  margin-bottom: 22px;
}

.score-cell { display: flex; flex-direction: column; align-items: center; padding: 18px 10px; background: var(--panel); }
.score-cell--mid { border-left: 1px solid var(--border-dim); border-right: 1px solid var(--border-dim); }

.score-big   { font-size: 32px; font-weight: bold; line-height: 1; margin-bottom: 5px; }
.score-green { color: var(--green); }
.score-red   { color: var(--red); }

.score-key { font-size: 9px; text-transform: uppercase; letter-spacing: 0.1em; color: var(--text-dim); }

.res-section { margin-bottom: 22px; }

.res-heading {
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: 0.12em;
  color: var(--text-dim);
  margin-bottom: 10px;
  padding-bottom: 6px;
  border-bottom: 1px solid var(--border-dim);
}

.res-none { font-size: 13px; color: var(--text-dim); padding: 6px 0; }
.col-r    { text-align: right; }

.charts-grid { display: grid; grid-template-columns: 1fr 1fr 1fr; gap: 14px; }

.chart-box {
  background: var(--panel);
  border: 1px solid var(--border);
  border-radius: 5px;
  padding: 12px 14px;
  min-height: 180px;
}
.chart-box--wide { grid-column: 1 / -1; }

/* ====================================================================
   RESPONSIVE — stack on narrow viewports (mirrors index.html behaviour)
   ==================================================================== */
@media (max-width: 900px) {
  .charts-grid     { grid-template-columns: 1fr; }
  .chart-box--wide { grid-column: 1; }
  .score-big       { font-size: 24px; }
  .score-grid      { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 560px) {
  .question-text { font-size: 48px; }
  .answer-input  { font-size: 22px; width: 160px; }
  .game-hud      { padding: 8px 14px; }
  .hud-timer     { font-size: 24px; }
}