/* ═══════════════════════════════════════════════════════════════════════════
   Audi 2.7T engine assembly guide
   Same family as the wiring-diagram pages: Audi red on near-black, with a
   light theme for the garage and for printing the torque sheet.
   ═══════════════════════════════════════════════════════════════════════════ */

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

:root {
  --bg:       #0f1117;
  --panel:    #181c27;
  --panel-2:  #1d2231;
  --border:   #2a2f3e;
  --accent:   #c8102e;
  --accent2:  #e63950;
  --text:     #e2e6ef;
  --text-hi:  #ffffff;
  --muted:    #7a8294;
  --faint:    #4a5266;
  --hover:    #232840;
  --active:   #1e2640;
  --ok:       #3fb97a;
  --warn:     #e3a33a;
  --bad:      #e5484d;
  --shadow:   #0007;
}

:root[data-theme="light"] {
  --bg:       #f3f4f7;
  --panel:    #ffffff;
  --panel-2:  #f0f2f6;
  --border:   #d8dce5;
  --accent:   #c8102e;
  --accent2:  #b00d27;
  --text:     #1b1f2a;
  --text-hi:  #000000;
  --muted:    #5f6778;
  --faint:    #9aa1b0;
  --hover:    #eceff5;
  --active:   #fbe9ec;
  --ok:       #1d8a55;
  --warn:     #a8680a;
  --bad:      #c32127;
  --shadow:   #0000001a;
}

html, body {
  height: 100%; overflow: hidden;
  font-family: 'Segoe UI', system-ui, sans-serif;
  background: var(--bg); color: var(--text);
  font-size: 14px; line-height: 1.5;
}
.num { font-variant-numeric: tabular-nums; }

/* ── Layout ── */
.app { display: grid; grid-template-columns: 280px minmax(0, 1fr); grid-template-rows: 56px 1fr; height: 100vh; }

/* ── Header ── */
header {
  grid-column: 1 / -1;
  display: flex; align-items: center; gap: 14px;
  padding: 0 20px;
  background: var(--panel);
  border-bottom: 1px solid var(--border);
  box-shadow: 0 1px 8px var(--shadow);
  z-index: 10;
}
.logo-ring { width: 32px; height: 32px; border: 2.5px solid var(--accent); border-radius: 50%; display: grid; place-items: center; flex-shrink: 0; }
.logo-ring svg { width: 18px; height: 18px; fill: var(--accent); }
header h1 { font-size: 15px; font-weight: 600; letter-spacing: .03em; white-space: nowrap; }
header h1 span { color: var(--accent); }

.head-progress {
  margin-left: auto; display: flex; align-items: center; gap: 10px;
  font-size: 12px; color: var(--muted); white-space: nowrap;
}
.head-progress .bar { width: 120px; height: 5px; background: var(--border); border-radius: 3px; overflow: hidden; }
.head-progress .bar i { display: block; height: 100%; width: 0; background: var(--accent); transition: width .25s; }

.seg { display: inline-flex; border: 1px solid var(--border); border-radius: 6px; overflow: hidden; flex-shrink: 0; }
.seg button {
  padding: 5px 10px; background: var(--panel-2); border: none; color: var(--muted);
  font: inherit; font-size: 12px; cursor: pointer;
}
.seg button + button { border-left: 1px solid var(--border); }
.seg button[aria-pressed="true"] { background: var(--accent); color: #fff; }

.icon-btn {
  flex-shrink: 0; width: 32px; height: 32px;
  background: var(--panel-2); border: 1px solid var(--border); border-radius: 6px;
  color: var(--muted); font-size: 14px; cursor: pointer;
  display: grid; place-items: center;
  transition: border-color .15s, color .15s;
}
.icon-btn:hover { border-color: var(--accent); color: var(--text); }

.hub-btn {
  display: flex; align-items: center; gap: 7px; flex-shrink: 0;
  padding: 6px 11px; border-radius: 6px;
  background: var(--hover); border: 1px solid var(--border);
  color: var(--muted); font-size: 12px; text-decoration: none; white-space: nowrap;
  transition: border-color .15s, color .15s;
}
.hub-btn:hover { border-color: var(--accent); color: var(--text); }
.hub-btn svg { width: 17px; height: 17px; stroke: currentColor; stroke-width: 1.6; fill: none; }

.menu-btn {
  display: none; align-items: center; justify-content: center;
  width: 36px; height: 36px; flex-shrink: 0;
  background: none; border: none; cursor: pointer; color: var(--text); border-radius: 6px;
}
.menu-btn:hover { background: var(--hover); }
.menu-btn svg { width: 20px; height: 20px; stroke: currentColor; stroke-width: 2; fill: none; stroke-linecap: round; }

/* ── Sidebar ── */
.sidebar {
  background: var(--panel); border-right: 1px solid var(--border);
  overflow-y: auto; display: flex; flex-direction: column;
}
.sidebar::-webkit-scrollbar { width: 4px; }
.sidebar::-webkit-scrollbar-thumb { background: var(--border); border-radius: 2px; }

.side-label {
  padding: 14px 16px 6px;
  font-size: 10px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase;
  color: var(--muted);
}
.step-item {
  display: flex; align-items: center; gap: 10px;
  padding: 8px 16px; cursor: pointer;
  font-size: 13px; color: var(--text);
  border-left: 2px solid transparent;
  background: none; border-top: none; border-right: none; border-bottom: none;
  width: 100%; text-align: left; font-family: inherit;
  transition: background .1s;
}
.step-item:hover { background: var(--hover); }
.step-item.active { background: var(--active); border-left-color: var(--accent); }
.step-dot {
  width: 22px; height: 22px; flex-shrink: 0; border-radius: 50%;
  display: grid; place-items: center;
  font-size: 10.5px; font-weight: 700; color: var(--muted);
  border: 1.5px solid var(--border);
}
.step-item.active .step-dot { border-color: var(--accent); color: var(--accent); }
.step-item.done .step-dot { background: var(--ok); border-color: var(--ok); color: #fff; }
.step-name { flex: 1; min-width: 0; line-height: 1.3; }
.step-count { font-size: 10px; color: var(--muted); }

.side-foot { margin-top: auto; padding: 14px 16px 18px; border-top: 1px solid var(--border); }
.facts { display: grid; grid-template-columns: auto 1fr; gap: 3px 12px; font-size: 11.5px; }
.facts dt { color: var(--muted); }
.facts dd { color: var(--text); }
.reset-btn {
  margin-top: 14px; width: 100%; padding: 7px; border-radius: 6px;
  background: none; border: 1px solid var(--border); color: var(--muted);
  font: inherit; font-size: 12px; cursor: pointer;
}
.reset-btn:hover { border-color: var(--bad); color: var(--bad); }

/* ── Main ── */
.main { overflow-y: auto; }
.main::-webkit-scrollbar { width: 6px; }
.main::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }
.page { max-width: 980px; margin: 0 auto; padding: 26px 26px 90px; }

.disclaimer {
  display: flex; gap: 10px; align-items: flex-start;
  padding: 10px 14px; margin-bottom: 22px;
  border: 1px solid color-mix(in srgb, var(--warn) 45%, transparent);
  background: color-mix(in srgb, var(--warn) 9%, var(--panel));
  border-radius: 8px; font-size: 12.5px; color: var(--text);
}
.disclaimer b { color: var(--warn); }

.step-head { display: flex; align-items: flex-start; gap: 16px; margin-bottom: 18px; }
.step-big {
  width: 46px; height: 46px; flex-shrink: 0; border-radius: 10px;
  display: grid; place-items: center;
  font-size: 18px; font-weight: 700; color: var(--accent);
  background: color-mix(in srgb, var(--accent) 12%, var(--panel));
  border: 1px solid color-mix(in srgb, var(--accent) 35%, transparent);
}
.step-kicker { font-size: 11px; letter-spacing: .12em; text-transform: uppercase; color: var(--muted); }
.step-title { font-size: 22px; font-weight: 600; line-height: 1.25; color: var(--text-hi); }
.step-summary { margin-top: 4px; color: var(--muted); max-width: 70ch; }

.card {
  background: var(--panel); border: 1px solid var(--border); border-radius: 10px;
  margin-bottom: 18px; overflow: hidden;
}
.card-head {
  display: flex; align-items: center; gap: 10px;
  padding: 11px 16px; border-bottom: 1px solid var(--border);
  font-size: 11px; font-weight: 700; letter-spacing: .12em; text-transform: uppercase; color: var(--muted);
}
.card-head .spacer { flex: 1; }
.card-body { padding: 14px 16px; }

.cautions { border-color: color-mix(in srgb, var(--accent) 45%, var(--border)); }
.cautions .card-head { color: var(--accent2); }
.cautions ul { list-style: none; display: grid; gap: 8px; }
.cautions li { padding-left: 18px; position: relative; }
.cautions li::before { content: '!'; position: absolute; left: 0; top: 0; font-weight: 800; color: var(--accent2); }

.chips { display: flex; flex-wrap: wrap; gap: 6px; }
.chip {
  padding: 3px 9px; border-radius: 999px; font-size: 12px;
  background: var(--panel-2); border: 1px solid var(--border); color: var(--text);
}

/* Checklist */
.tasks { list-style: none; }
.tasks li + li { border-top: 1px solid var(--border); }
.tasks label { display: flex; gap: 12px; align-items: flex-start; padding: 10px 16px; cursor: pointer; }
.tasks label:hover { background: var(--hover); }
.tasks input { margin-top: 3px; width: 16px; height: 16px; accent-color: var(--accent); flex-shrink: 0; }
.tasks input:checked + span { color: var(--muted); text-decoration: line-through; text-decoration-color: var(--faint); }

/* Torque table */
.tq { width: 100%; border-collapse: collapse; font-size: 13px; }
.tq th {
  text-align: left; font-size: 10.5px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase;
  color: var(--muted); padding: 9px 12px; border-bottom: 1px solid var(--border);
}
.tq td { padding: 10px 12px; border-bottom: 1px solid var(--border); vertical-align: top; }
.tq tr:last-child td { border-bottom: none; }
.tq td:first-child { width: 36%; }
.tq .item { font-weight: 500; color: var(--text-hi); }
.tq .sub { font-size: 11.5px; color: var(--muted); margin-top: 2px; }
.stages { display: flex; flex-wrap: wrap; gap: 5px; align-items: center; }
.stage {
  display: inline-flex; align-items: center; gap: 5px;
  padding: 3px 9px; border-radius: 6px; cursor: pointer;
  font: inherit; font-size: 13px; font-weight: 600; white-space: nowrap;
  background: var(--panel-2); border: 1px solid var(--border); color: var(--text-hi);
}
.stage:hover { border-color: var(--accent); }
.stage.done { background: color-mix(in srgb, var(--ok) 16%, var(--panel)); border-color: var(--ok); color: var(--ok); }
.stage.done::before { content: '✓'; font-size: 11px; }
.stage.text { cursor: default; font-weight: 500; }
.stage-arrow { color: var(--faint); font-size: 11px; }

.badge {
  display: inline-block; padding: 1px 6px; border-radius: 4px;
  font-size: 10px; font-weight: 700; letter-spacing: .05em; text-transform: uppercase; white-space: nowrap;
}
.b-new  { background: color-mix(in srgb, var(--accent) 16%, transparent); color: var(--accent2); border: 1px solid color-mix(in srgb, var(--accent) 45%, transparent); }
.b-multiple { background: color-mix(in srgb, var(--ok) 14%, transparent); color: var(--ok); }
.b-single   { background: color-mix(in srgb, var(--warn) 14%, transparent); color: var(--warn); }
.b-conflict { background: color-mix(in srgb, var(--bad) 14%, transparent); color: var(--bad); }
.b-user     { background: color-mix(in srgb, var(--accent) 14%, transparent); color: var(--accent2); }
.src { font-size: 11px; }
.src a { color: var(--muted); }
.src a:hover { color: var(--accent2); }
.seq-link {
  background: none; border: none; padding: 0; cursor: pointer;
  color: var(--accent2); font: inherit; font-size: 11.5px; text-decoration: underline;
}

/* Sequence diagram */
.seq-wrap { display: grid; grid-template-columns: minmax(0, 1fr) 240px; gap: 18px; align-items: start; }
.seq-svg { width: 100%; height: auto; display: block; }
.seq-svg .outline { fill: var(--panel-2); stroke: var(--border); stroke-width: 2; }
.seq-svg .bore { fill: none; stroke: var(--border); stroke-width: 1.5; stroke-dasharray: 4 4; }
.seq-svg .cap { fill: var(--hover); stroke: var(--border); stroke-width: 1.5; }
.seq-svg .bolt circle { fill: var(--panel); stroke: var(--muted); stroke-width: 2; transition: fill .15s, stroke .15s; }
.seq-svg .bolt text { fill: var(--text); font-size: 13px; font-weight: 700; text-anchor: middle; dominant-baseline: central; font-family: inherit; }
.seq-svg .bolt.past circle { fill: color-mix(in srgb, var(--ok) 30%, var(--panel)); stroke: var(--ok); }
.seq-svg .bolt.now circle { fill: var(--accent); stroke: var(--accent); }
.seq-svg .bolt.now text { fill: #fff; }
.seq-svg .lbl { fill: var(--muted); font-size: 11px; letter-spacing: .1em; text-transform: uppercase; font-family: inherit; }
.seq-side h4 { font-size: 14px; color: var(--text-hi); margin-bottom: 6px; }
.seq-side p { font-size: 12.5px; color: var(--muted); margin-bottom: 12px; }
.seq-now { font-size: 30px; font-weight: 700; color: var(--accent); line-height: 1; margin-bottom: 4px; }
.seq-ctrl { display: flex; gap: 6px; margin-top: 8px; }
.btn {
  padding: 7px 12px; border-radius: 6px; cursor: pointer;
  background: var(--panel-2); border: 1px solid var(--border); color: var(--text);
  font: inherit; font-size: 12.5px;
}
.btn:hover { border-color: var(--accent); }
.btn-primary { background: var(--accent); border-color: var(--accent); color: #fff; }
.btn-primary:hover { background: var(--accent2); }

/* 3D viewer */
.viewer { position: relative; height: clamp(260px, 46vw, 440px); background: var(--panel-2); touch-action: none; }
.viewer-canvas { display: block; width: 100%; height: 100%; cursor: grab; }
.viewer-canvas:active { cursor: grabbing; }
.viewer-tip {
  position: absolute; pointer-events: none; z-index: 2;
  padding: 4px 9px; border-radius: 5px; max-width: 70%;
  background: var(--panel); border: 1px solid var(--border); box-shadow: 0 2px 10px var(--shadow);
  font-size: 12px; color: var(--text-hi); white-space: nowrap; overflow: hidden; text-overflow: ellipsis;
}
.viewer-bar {
  display: flex; flex-wrap: wrap; align-items: center; gap: 10px 16px;
  padding: 10px 16px; border-top: 1px solid var(--border); font-size: 12.5px; color: var(--muted);
}
.viewer-bar .spacer { flex: 1; }
.vb-range { display: flex; align-items: center; gap: 8px; }
.vb-range input { width: 130px; accent-color: var(--accent); }
.vb-check { display: flex; align-items: center; gap: 6px; cursor: pointer; }
.vb-check input { accent-color: var(--accent); }
.viewer-note { padding: 0 16px 12px; font-size: 11.5px; color: var(--faint); }
.viewer-note a { color: var(--muted); }
.legend { display: inline-flex; align-items: center; gap: 5px; font-weight: 600; letter-spacing: .06em; }
.legend i { width: 10px; height: 10px; border-radius: 2px; display: inline-block; }
.lg-now { background: var(--accent); }
.lg-done { background: #9aa3ad; }

.nav-row { display: flex; gap: 10px; align-items: center; margin-top: 8px; }
.nav-row .spacer { flex: 1; }

/* All-torques sheet */
.sheet-group td { background: var(--panel-2); font-size: 11px; font-weight: 700; letter-spacing: .1em; text-transform: uppercase; color: var(--muted); }

.missing { font-size: 12.5px; color: var(--muted); }
.missing li { margin-left: 18px; }

/* ── Backdrop for the mobile drawer ── */
.overlay { display: none; position: fixed; inset: 0; z-index: 99; background: #00000080; backdrop-filter: blur(2px); }
.overlay.visible { display: block; }

/* ── Responsive ── */
@media (max-width: 1023px) {
  .app { grid-template-columns: 240px minmax(0, 1fr); }
  .hub-btn span { display: none; }
  .hub-btn { padding: 6px 8px; }
  .head-progress .bar { display: none; }
  .seq-wrap { grid-template-columns: 1fr; }
}

@media (max-width: 639px) {
  .app { grid-template-columns: minmax(0, 1fr); grid-template-rows: 52px 1fr; }
  header { min-width: 0; }
  .head-progress { display: none; }
  .menu-btn { display: flex; }
  .sidebar {
    position: fixed; top: 52px; bottom: 0; left: -290px;
    width: 290px; z-index: 100;
    transition: left .25s cubic-bezier(.4,0,.2,1);
    box-shadow: 4px 0 24px #000a;
  }
  .sidebar.open { left: 0; }
  header { padding: 0 10px; gap: 6px; height: 52px; }
  header h1 { flex: 1; }
  header h1 { font-size: 14px; min-width: 0; overflow: hidden; text-overflow: ellipsis; }
  .logo-ring { display: none; }
  .seg button { padding: 5px 7px; }
  .head-progress span { display: none; }
  .page { padding: 16px 16px 80px; }
  .step-title { font-size: 18px; }
  .step-big { width: 38px; height: 38px; font-size: 15px; }
}

@media (max-width: 899px) {
  /* Torque table collapses to stacked rows */
  .tq thead { display: none; }
  .tq, .tq tbody, .tq tr, .tq td, .tq td:first-child { display: block; width: 100%; }
  .tq tr { padding: 10px 0; border-bottom: 1px solid var(--border); }
  .tq tr:last-child { border-bottom: none; }
  .tq td { border: none; padding: 3px 14px; }
  .tq td[data-l]::before {
    content: attr(data-l); display: block;
    font-size: 10px; font-weight: 700; letter-spacing: .08em; text-transform: uppercase; color: var(--faint);
  }
  .sheet-group td { padding: 8px 14px; }
}

/* ── Print: the torque sheet on paper ── */
@media print {
  html, body { overflow: visible; height: auto; background: #fff; color: #000; }
  .app { display: block; height: auto; }
  header, .sidebar, .overlay, .nav-row, .disclaimer button, .no-print { display: none !important; }
  .main { overflow: visible; }
  .card { break-inside: avoid; border-color: #bbb; }
}