/* ═══════════════════════════════════════════════════════════
   Drilling Machine Simulator — style.css  v9
   Accent: #43a047 (green)
   ═══════════════════════════════════════════════════════════ */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

:root {
  --bg:        #0d1117;
  --surface:   #161b27;
  --surface2:  #1f2535;
  --border:    #2a3050;
  --accent:    #43a047;
  --accent-lo: rgba(67,160,71,.22);
  --green:     #3ddc84;
  --red:       #ff5555;
  --gold:      #f5c842;
  --text:      #dde3f0;
  --text-dim:  #6b7a99;
  --font:      'Segoe UI', system-ui, sans-serif;
  --mono:      'Courier New', monospace;
  --radius:    12px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--font);
  min-height: 100vh;
  padding: 0 12px 32px;
}

/* ── Page wrapper ── */
#app {
  max-width: 1440px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

/* ── Header ── */
header { text-align: center; padding: 6px 0 2px; }
header h1 {
  font-size: 1.75rem;
  font-weight: 700;
  background: linear-gradient(120deg, var(--accent) 0%, #66bb6a 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.subtitle { color: var(--text-dim); font-size: .82rem; margin-top: 2px; }

/* ── Mode / controls bar ── */
.controls-bar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 10px;
  padding: 8px 14px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
}
.ctrl-group { display: flex; align-items: center; gap: 8px; }
.ctrl-label {
  font-size: .7rem; text-transform: uppercase; letter-spacing: .06em;
  color: var(--text-dim); white-space: nowrap;
}

/* ── Pill tabs (mode row) ── */
.pill-tabs {
  display: flex; background: var(--bg); border-radius: 8px; padding: 3px; gap: 2px;
}
.pill {
  padding: 5px 13px; border: none; background: transparent; color: var(--text-dim);
  border-radius: 6px; cursor: pointer; font-size: .81rem;
  transition: background .18s, color .18s, box-shadow .18s;
}
.pill.active {
  background: var(--accent); color: #fff; box-shadow: 0 0 12px var(--accent-lo);
}
.pill:hover:not(.active) { background: var(--surface2); color: var(--text); }

/* ── Buttons ── */
.btn {
  padding: 7px 16px; border: none; border-radius: 8px; cursor: pointer;
  font-size: .83rem; font-weight: 600;
  transition: filter .18s, box-shadow .18s, opacity .18s;
}
.btn:disabled { opacity: .38; cursor: not-allowed; }
.btn-primary { background: var(--accent); color: #fff; }
.btn-primary:not(:disabled):hover { filter: brightness(1.12); box-shadow: 0 0 10px var(--accent-lo); }
.btn-ghost { background: var(--surface2); color: var(--text); border: 1px solid var(--border); }
.btn-ghost:hover { background: var(--border); }

/* ══════════════════════════════════════════════════════════
   SIMULATE MODE — two-column canvas row + full-width controls
   ══════════════════════════════════════════════════════════ */

/* Outer row: machine + analysis side by side, both cards same height */
.canvas-row {
  display: flex;
  gap: 12px;
  align-items: stretch;
}

/* ── Machine canvas card ── */
.canvas-card-machine {
  flex: 1 1 0;
  min-width: 0;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 8px;
  overflow: hidden;
}
.canvas-card-machine canvas {
  display: block; width: 100%; height: auto; aspect-ratio: 1120 / 1260; touch-action: pan-y;
}

/* ── Analysis canvas card (same 560×700 aspect as machine) ── */
.canvas-card-graph {
  flex: 1 1 0;
  min-width: 0;
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 8px 10px;
  display: flex; flex-direction: column;
}
.canvas-card-graph canvas {
  display: block; width: 100%; height: auto; touch-action: pan-y;
}

/* ── Graph footer: badges left, buttons right ── */
.graph-footer {
  display: flex; align-items: center; justify-content: space-between;
  gap: 8px; margin-top: 6px; flex-wrap: wrap;
}
.graph-badges {
  display: flex; gap: 6px; flex-wrap: wrap;
}
.graph-badge {
  display: flex; align-items: center; gap: 4px;
  padding: 3px 8px;
  background: var(--surface2); border: 1px solid var(--border); border-radius: 6px;
  font-size: .68rem; color: var(--text-dim);
}
.graph-badge-val {
  font-family: var(--mono); font-weight: 700; color: var(--text); font-size: .74rem;
}

/* ══════════════════════════════════════════════════════════
   CONTROLS CARD — full width below both canvases
   ══════════════════════════════════════════════════════════ */
.controls-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 14px 16px;
  display: flex; flex-direction: column; gap: 12px;
}

/* Operation / Material rows */
.ctrl-row {
  display: flex; align-items: center; gap: 10px; flex-wrap: wrap;
}

/* Operation / material pill tabs */
.config-tabs {
  display: flex; gap: 4px; flex-wrap: wrap;
}
.config-pill {
  padding: 4px 11px; border: 1px solid var(--border); border-radius: 6px;
  background: var(--surface2); color: var(--text-dim); cursor: pointer;
  font-size: .75rem; transition: all .15s;
}
.config-pill.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.config-pill:hover:not(.active) { border-color: var(--accent); color: var(--text); }

/* Sliders grid — 3 columns, 5 sliders evenly distributed */
.sliders-grid {
  display: grid;
  grid-template-columns: 1fr 1fr 1fr;
  gap: 10px 28px;
  border-top: 1px solid var(--border);
  padding-top: 12px;
}
.slider-group {
  display: flex; flex-direction: column; gap: 5px;
  min-width: 0;
}
.slider-group label {
  display: flex; justify-content: space-between; align-items: baseline;
  font-size: .67rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-dim);
}
.slider-val {
  font-family: var(--mono); font-size: .76rem; color: var(--accent); font-weight: 700;
}
.slider-group input[type="range"] {
  -webkit-appearance: none; appearance: none;
  width: 100%; height: 4px;
  background: var(--border); border-radius: 2px; outline: none;
  cursor: pointer;
}
.slider-group input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none; appearance: none;
  width: 14px; height: 14px;
  background: var(--accent); border-radius: 50%;
  border: 2px solid var(--bg); cursor: pointer;
}

/* Action buttons — bottom-right of graph card footer */
.action-btns {
  display: flex; gap: 8px; flex-shrink: 0;
}

/* Operation + Material + Sliders unified panel inside graph card —
   flex:1 so it grows to fill whatever height remains after the canvas */
.graph-controls {
  flex: 1;
  border-top: 1px solid var(--border);
  padding: 12px 4px 6px;
  margin-top: 6px;
  display: flex;
  flex-direction: column;
  justify-content: space-evenly; /* distributes Op / Mat / Sliders evenly */
}

/* ── Larger, more readable op/mat chips inside graph card ── */
.graph-controls .ctrl-label {
  font-size: .75rem;
  min-width: 80px;
}
.graph-controls .config-tabs {
  gap: 5px;
}
.graph-controls .config-pill {
  padding: 6px 16px;
  font-size: .8rem;
  border-radius: 8px;
  font-weight: 500;
}

/* ── More spacious sliders inside graph card ── */
.graph-controls .sliders-grid {
  border-top: none;
  padding-top: 0;
  row-gap: 14px;
  column-gap: 20px;
}
.graph-controls .slider-group {
  gap: 7px;
}
.graph-controls .slider-group label {
  font-size: .72rem;
}
.graph-controls .slider-val {
  font-size: .8rem;
}
.graph-controls .slider-group input[type="range"] {
  height: 5px;
}
.graph-controls .slider-group input[type="range"]::-webkit-slider-thumb {
  width: 16px;
  height: 16px;
}

/* ══════════════════════════════════════════════════════════
   READOUT GRID — 4-column KPI cards
   ══════════════════════════════════════════════════════════ */
.readout-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 6px;
}
.readout-card {
  background: var(--surface2); border: 1px solid var(--border); border-radius: 8px;
  padding: 8px 6px; text-align: center;
}
.readout-label {
  font-size: .6rem; text-transform: uppercase; letter-spacing: .04em;
  color: var(--text-dim); margin-bottom: 3px;
  white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.readout-value {
  font-family: var(--mono); font-size: 1.05rem; font-weight: 700; color: var(--accent);
  line-height: 1.1;
}
.readout-unit { font-size: .63rem; color: var(--text-dim); margin-top: 2px; }

/* ══════════════════════════════════════════════════════════
   EXPLORE MODE
   ══════════════════════════════════════════════════════════ */
.explore-wrapper {}
.explore-cats {
  display: flex; gap: 4px; flex-wrap: wrap; margin-bottom: 10px;
}
.explore-grid {
  display: grid; grid-template-columns: repeat(auto-fill, minmax(155px, 1fr));
  gap: 8px; margin-bottom: 14px;
}
.explore-btn {
  padding: 8px 10px; background: var(--surface2); border: 1px solid var(--border);
  border-radius: 8px; color: var(--text-dim); cursor: pointer; font-size: .78rem;
  text-align: left; transition: all .18s;
}
.explore-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.explore-btn:hover:not(.active) { border-color: var(--accent); color: var(--text); }
.explore-info {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 16px 20px; margin-bottom: 14px;
}
.explore-info h3 { font-size: 1rem; color: var(--accent); margin-bottom: 6px; }
.explore-info p  { font-size: .84rem; color: var(--text-dim); line-height: 1.55; }
.explore-info .formula-box {
  margin-top: 10px; padding: 10px 14px;
  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
  font-family: var(--mono); font-size: .82rem; color: var(--accent);
}
.explore-info .example-box {
  margin-top: 10px; padding: 10px 14px;
  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
  font-size: .8rem; color: var(--text-dim); line-height: 1.5;
}
.explore-info .example-box strong { color: var(--text); }
.explore-canvas-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: var(--radius); padding: 10px; overflow: hidden;
}
.explore-canvas-card canvas { display: block; width: 100%; height: auto; }

/* ══════════════════════════════════════════════════════════
   PRACTICE MODE
   ══════════════════════════════════════════════════════════ */
.practice-panel {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px 22px;
}
.practice-prompt { font-size: .92rem; line-height: 1.5; margin-bottom: 14px; }
.practice-input-row { display: flex; gap: 8px; align-items: center; margin-bottom: 10px; }
.practice-input-row input {
  width: 120px; padding: 6px 10px; border: 1px solid var(--border); border-radius: 6px;
  background: var(--bg); color: var(--text); font-family: var(--mono); font-size: .88rem;
}
.practice-input-row .unit { font-size: .78rem; color: var(--text-dim); }
.practice-feedback { font-size: .86rem; font-weight: 600; margin-bottom: 8px; min-height: 1.2em; }
.practice-feedback.ok  { color: var(--green); }
.practice-feedback.err { color: var(--red); }
.practice-solution {
  display: none; margin-top: 10px; padding: 12px 14px;
  background: var(--bg); border: 1px solid var(--border); border-radius: 8px;
  font-size: .82rem; line-height: 1.6; color: var(--text-dim);
}
.practice-solution strong { color: var(--text); }
.practice-btns { display: flex; gap: 8px; margin-top: 12px; }
.practice-score { font-size: .82rem; color: var(--text-dim); margin-left: auto; align-self: center; }
.practice-score span { color: var(--text); font-weight: 700; }

/* ══════════════════════════════════════════════════════════
   QUIZ MODE
   ══════════════════════════════════════════════════════════ */
.quiz-panel {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 18px 22px;
}
.quiz-counter { font-size: .74rem; color: var(--text-dim); margin-bottom: 8px; }
.quiz-prompt { font-size: .92rem; line-height: 1.5; margin-bottom: 14px; }
.quiz-options { display: grid; grid-template-columns: 1fr 1fr; gap: 8px; margin-bottom: 12px; }
.quiz-opt {
  padding: 10px 14px; background: var(--surface2); border: 1px solid var(--border);
  border-radius: 8px; cursor: pointer; font-size: .82rem; color: var(--text);
  transition: all .18s; text-align: left;
}
.quiz-opt:hover { border-color: var(--accent); }
.quiz-opt.correct { background: rgba(61,220,132,.15); border-color: var(--green); color: var(--green); }
.quiz-opt.wrong   { background: rgba(255,85,85,.15); border-color: var(--red); color: var(--red); }
.quiz-opt.disabled { pointer-events: none; opacity: .6; }
.quiz-num-row { display: flex; gap: 8px; align-items: center; margin-bottom: 12px; }
.quiz-num-row input {
  width: 120px; padding: 6px 10px; border: 1px solid var(--border); border-radius: 6px;
  background: var(--bg); color: var(--text); font-family: var(--mono); font-size: .88rem;
}
.quiz-feedback { font-size: .86rem; font-weight: 600; min-height: 1.2em; margin-bottom: 8px; }
.quiz-feedback.ok  { color: var(--green); }
.quiz-feedback.err { color: var(--red); }
.quiz-btns { display: flex; gap: 8px; }
.quiz-result {
  display: none;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  padding: 20px 22px;
}
.qr-title { font-size: 1rem; font-weight: 700; margin-bottom: 4px; }
.qr-stars { font-size: 1.4rem; margin-bottom: 6px; }
.qr-score { font-size: .92rem; font-weight: 700; margin-bottom: 12px; }
.qr-score.perfect { color: var(--gold); }
.qr-score.good    { color: var(--green); }
.qr-score.poor    { color: var(--red); }
.qr-table { width: 100%; border-collapse: collapse; font-size: .8rem; margin-bottom: 14px; }
.qr-table th { text-align: left; padding: 6px 8px; border-bottom: 1px solid var(--border); color: var(--text-dim); }
.qr-table td { padding: 6px 8px; border-bottom: 1px solid var(--border); }
.qr-row.ok  { border-left: 3px solid var(--green); }
.qr-row.err { border-left: 3px solid var(--red); }

/* ── SEO article ── */
.seo-article {
  padding: 20px;
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  line-height: 1.65; color: var(--text-dim); font-size: .87rem;
}
.seo-article h2 { font-size: 1.15rem; color: var(--text); margin-bottom: 8px; }
.seo-article h3 { font-size: .96rem; color: var(--text); margin: 14px 0 5px; }
.seo-article p  { margin-bottom: 9px; }

/* ══════════════════════════════════════════════════════════
   DRILL BIT SELECTOR POPUP
   ══════════════════════════════════════════════════════════ */
.bit-popup {
  position: fixed; inset: 0; z-index: 9999;
  background: rgba(0,0,0,0.72);
  display: flex; align-items: center; justify-content: center;
  backdrop-filter: blur(4px);
}
.bit-popup-inner {
  background: var(--surface); border: 1px solid var(--border); border-radius: var(--radius);
  width: 94%; max-width: 520px; max-height: 92vh; overflow-y: auto;
  box-shadow: 0 12px 40px rgba(0,0,0,0.6);
}
.bit-popup-header {
  display: flex; align-items: center; justify-content: space-between;
  padding: 10px 14px; border-bottom: 1px solid var(--border);
}
.bit-popup-header h3 { font-size: .9rem; color: var(--accent); margin: 0; }
.bit-popup-close {
  background: none; border: none; color: var(--text-dim); font-size: 1.3rem;
  cursor: pointer; padding: 2px 6px; border-radius: 4px;
}
.bit-popup-close:hover { background: var(--surface2); color: var(--text); }
.bit-popup-body { display: flex; gap: 10px; padding: 10px 14px; }
.bit-popup-types { display: flex; flex-direction: column; gap: 6px; flex: 1 1 55%; min-width: 0; }
.bit-type-card {
  display: flex; align-items: center; gap: 8px;
  padding: 6px 8px; border: 1px solid var(--border); border-radius: 8px;
  background: var(--surface2); cursor: pointer; transition: all .15s;
}
.bit-type-card:hover { border-color: var(--accent); }
.bit-type-card.active { border-color: var(--accent); background: var(--accent-lo); }
.bit-type-card canvas { flex-shrink: 0; }
.bit-type-info { min-width: 0; }
.bit-type-name { font-size: .78rem; font-weight: 700; color: var(--text); }
.bit-type-std  { font-size: .64rem; color: var(--accent); font-family: var(--mono); }
.bit-type-desc { font-size: .62rem; color: var(--text-dim); line-height: 1.3; margin-top: 2px; }
.bit-popup-right { flex: 1 1 40%; display: flex; flex-direction: column; gap: 8px; }
.bit-popup-desc {
  font-size: .76rem; color: var(--text-dim); line-height: 1.4;
  padding: 8px; background: var(--bg); border-radius: 6px; min-height: 50px;
}
.bit-popup-sizes-label { font-size: .68rem; text-transform: uppercase; letter-spacing: .05em; color: var(--text-dim); }
.bit-popup-sizes { display: grid; grid-template-columns: repeat(5, 1fr); gap: 4px; }
.bit-size-btn {
  padding: 5px 2px; border: 1px solid var(--border); border-radius: 6px;
  background: var(--surface2); color: var(--text); cursor: pointer;
  font-size: .76rem; font-family: var(--mono); text-align: center; transition: all .15s;
}
.bit-size-btn:hover { border-color: var(--accent); color: var(--accent); }
.bit-size-btn.active { background: var(--accent); color: #fff; border-color: var(--accent); }
.bit-popup-actions { display: flex; gap: 8px; margin-top: auto; padding-top: 6px; }
.bit-popup-actions .btn { flex: 1; padding: 7px 0; font-size: .82rem; }

/* ══════════════════════════════════════════════════════════
   RESPONSIVE
   ══════════════════════════════════════════════════════════ */

/* Tablet: stack canvases at 960px */
@media (max-width: 960px) {
  .canvas-row { flex-direction: column; }
  .canvas-card-machine { width: 100%; flex: 0 0 auto; }
  .canvas-card-graph { flex: 0 0 auto; }
  .readout-grid { grid-template-columns: repeat(4, 1fr); }
}

/* Tablet: 2-col sliders */
@media (max-width: 960px) and (min-width: 641px) {
  .sliders-grid { grid-template-columns: 1fr 1fr; }
}

/* Mobile: 640px and below */
@media (max-width: 640px) {
  body { padding: 0 8px 24px; }
  #app { gap: 8px; }
  header h1 { font-size: 1.35rem; }
  .subtitle { font-size: .76rem; }

  /* Single column sliders */
  .sliders-grid { grid-template-columns: 1fr; gap: 10px; }
  .action-btns { justify-content: stretch; }
  .action-btns .btn { flex: 1; }

  /* 2-col readouts */
  .readout-grid { grid-template-columns: 1fr 1fr; gap: 5px; }
  .readout-value { font-size: .95rem; }

  /* Quiz/practice */
  .quiz-options { grid-template-columns: 1fr; }
  .pill { padding: 5px 9px; font-size: .76rem; }
}

/* Extra-small: 400px */
@media (max-width: 400px) {
  .readout-grid { grid-template-columns: 1fr 1fr; }
  .controls-bar { gap: 8px; padding: 8px 10px; }
}