/* ============================================================
   DiagMyPCHub — "My computer won't turn on" tutorial
   Local styles only. Shared design tokens, header, buttons,
   tables, footer, toast, to-top and consent come from
   ../../css/style.css + ../../css/nav.css.
   Prefix: pow-
   ============================================================ */

/* ---------- Reading progress ---------- */
.pow-progress { position: fixed; top: 0; left: 0; right: 0; height: 3px; z-index: 70; pointer-events: none; }
.pow-progress > span {
  display: block;
  height: 100%;
  width: 0;
  background: linear-gradient(90deg, var(--blue), var(--cyan-bright));
  transition: width 0.1s linear;
}

/* ---------- Layout ---------- */
.pow-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  padding: clamp(28px, 4vw, 44px) 0 clamp(48px, 6vw, 72px);
}
@media (min-width: 1100px) {
  .pow-grid { grid-template-columns: 250px minmax(0, 1fr); gap: 56px; }
}

/* ---------- Table of contents ---------- */
.pow-toc { margin: 0; }
@media (min-width: 1100px) {
  .pow-toc {
    position: sticky;
    top: calc(var(--header-h) + 20px);
    align-self: start;
    max-height: calc(100vh - var(--header-h) - 40px);
    overflow-y: auto;
    padding-right: 6px;
  }
}
.pow-toc-title {
  font: 500 0.7rem var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  margin: 0 0 12px;
}
.pow-toc ul { display: grid; border-left: 2px solid var(--line); }
.pow-toc a {
  display: block;
  padding: 7px 14px;
  margin-left: -2px;
  border-left: 2px solid transparent;
  color: var(--ink-2);
  text-decoration: none;
  font-size: 0.86rem;
  line-height: 1.4;
  transition: color 0.2s, border-color 0.2s, background 0.2s;
}
.pow-toc a:hover { color: var(--ink); background: var(--tint); }
.pow-toc a.is-active {
  color: var(--blue-deep);
  border-left-color: var(--blue);
  font-weight: 600;
  background: var(--tint);
}

/* ---------- Article head ---------- */
.pow-head { max-width: 70ch; }
.pow-head h1 {
  font-size: clamp(1.9rem, 1.2rem + 2.6vw, 2.6rem);
  font-weight: 700;
  letter-spacing: -0.02em;
  line-height: 1.12;
  margin: 0 0 16px;
}
.pow-intro { color: var(--ink-2); font-size: 1.02rem; }

/* ---------- Article figure (auto-hiding placeholder) ---------- */
.pow-figure { margin: 26px 0 6px; }
.pow-figure[data-empty="true"] { display: none; }
.pow-figure img {
  width: 100%;
  height: auto;
  min-height: 0;
  border-radius: var(--radius);
  border: 1px solid var(--line);
  box-shadow: var(--shadow-1);
  display: block;
}
.pow-figure figcaption {
  font: 400 0.74rem/1.6 var(--font-mono);
  color: var(--ink-3);
  margin-top: 8px;
}

/* ---------- Symptom selector ---------- */
.pow-diag { margin: 30px 0 8px; }
.pow-diag-label { font: 600 1.08rem var(--font-display); margin: 0 0 12px; }
.pow-diag-opts { display: grid; gap: 10px; }
.pow-diag-opt {
  display: flex;
  align-items: center;
  gap: 10px;
  padding: 12px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: 10px;
  color: var(--ink);
  text-decoration: none;
  font-size: 0.92rem;
  transition: border-color 0.2s, background 0.2s, transform 0.2s, box-shadow 0.2s;
}
.pow-diag-opt::before {
  content: "";
  flex: none;
  width: 8px; height: 8px;
  border-radius: 50%;
  border: 2px solid var(--line-2);
  transition: border-color 0.2s, background 0.2s;
}
.pow-diag-opt:hover,
.pow-diag-opt:focus-visible {
  border-color: var(--blue);
  background: var(--tint);
  transform: translateY(-2px);
  box-shadow: var(--shadow-1);
}
.pow-diag-opt:hover::before,
.pow-diag-opt:focus-visible::before { border-color: var(--blue); background: var(--blue); }
.pow-diag-msg { min-height: 1.5em; margin: 12px 0 0; font-size: 0.88rem; color: var(--ink-2); }
.pow-diag-msg.is-on { border-left: 3px solid var(--blue); padding-left: 10px; }
@media (min-width: 600px) { .pow-diag-opts { grid-template-columns: 1fr 1fr; } }
@media (min-width: 1100px) { .pow-diag-opts { grid-template-columns: repeat(3, 1fr); } }

/* ---------- Most common causes ---------- */
.pow-most { margin: 26px 0 8px; }
.pow-most-label {
  font: 500 0.7rem var(--font-mono);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  color: var(--ink-3);
  margin: 0 0 12px;
}
.pow-most-grid { display: grid; grid-template-columns: 1fr; gap: 12px; }
.pow-most-card {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 14px 16px;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--ink);
  transition: border-color 0.2s, transform 0.2s, box-shadow 0.2s;
}
.pow-most-card:hover,
.pow-most-card:focus-visible { border-color: var(--blue); transform: translateY(-2px); box-shadow: var(--shadow-1); }
.pow-most-rank {
  flex: none;
  width: 26px; height: 26px;
  display: grid;
  place-items: center;
  border-radius: 8px;
  background: var(--tint);
  border: 1px solid var(--blue-soft);
  color: var(--blue-deep);
  font: 600 0.8rem var(--font-mono);
}
.pow-most-body { display: grid; gap: 3px; }
.pow-most-body strong { font: 600 0.95rem var(--font-body); }
.pow-most-body span { font-size: 0.84rem; color: var(--ink-2); }
@media (min-width: 640px) { .pow-most-grid { grid-template-columns: 1fr 1fr; } }

/* ---------- Section blocks ---------- */
.pow-sec { margin-top: clamp(40px, 5vw, 60px); scroll-margin-top: calc(var(--header-h) + 16px); }
.pow-sec-head { display: flex; align-items: flex-end; gap: 14px; margin-bottom: 12px; }
.pow-sec-index { font: 600 0.95rem var(--font-mono); color: var(--line-2); padding-bottom: 6px; flex: none; }
.pow-sec-kicker { font: 500 0.7rem var(--font-mono); text-transform: uppercase; letter-spacing: 0.16em; color: var(--blue); margin: 0 0 4px; }
.pow-sec-head h2 { font-size: clamp(1.3rem, 1rem + 1.2vw, 1.7rem); font-weight: 600; letter-spacing: -0.01em; margin: 0; }
.pow-sec-lede { color: var(--ink-2); font-size: 0.98rem; max-width: 75ch; margin: 0 0 20px; }

/* ---------- Accordion articles ---------- */
.pow-art {
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  margin-bottom: 14px;
  overflow: hidden;
  transition: border-color 0.2s, box-shadow 0.2s;
}
.pow-art[open] { border-color: var(--blue-soft); box-shadow: var(--shadow-1); }
.pow-art-sum {
  display: flex;
  align-items: center;
  gap: 14px;
  padding: 16px 18px;
  cursor: pointer;
  list-style: none;
}
.pow-art-sum::-webkit-details-marker { display: none; }
.pow-art-sum:hover { background: #f6f9fd; }
.pow-art-num {
  flex: none;
  width: 34px; height: 34px;
  display: grid;
  place-items: center;
  border-radius: 9px;
  background: var(--tint);
  border: 1px solid var(--blue-soft);
  color: var(--blue-deep);
  font-size: 0.74rem;
}
.pow-art-body { display: grid; gap: 3px; min-width: 0; flex: 1; }
.pow-art-title { font: 600 1.02rem var(--font-display); color: var(--ink); }
.pow-art-meta { display: flex; align-items: center; gap: 10px; }
.pow-art-time { font-size: 0.7rem; color: var(--ink-3); }
.pow-art-ico { position: relative; width: 14px; height: 14px; margin-left: auto; }
.pow-art-ico::before,
.pow-art-ico::after {
  content: "";
  position: absolute;
  inset: 6px 0 auto 0;
  height: 2px;
  background: var(--ink-3);
  border-radius: 2px;
  transition: transform 0.25s, background 0.25s;
}
.pow-art-ico::after { transform: rotate(90deg); }
.pow-art[open] .pow-art-ico::after { transform: rotate(0deg); }
.pow-art[open] .pow-art-ico::before,
.pow-art[open] .pow-art-ico::after { background: var(--blue); }
.pow-art-panel { display: grid; grid-template-rows: 0fr; transition: grid-template-rows 0.35s ease; }
.pow-art[open] .pow-art-panel { grid-template-rows: 1fr; }
.pow-art-inner {
  overflow: hidden;
  min-height: 0;
  visibility: hidden;
  transition: visibility 0s 0.35s;
  padding: 0 18px;
}
.pow-art[open] .pow-art-inner { visibility: visible; transition-delay: 0s; padding: 0 18px 20px; }
.pow-art-inner p { font-size: 0.95rem; color: var(--ink-2); max-width: 75ch; }
.pow-art-inner .table-wrap { margin: 16px 0; max-width: none; }

/* ---------- Decision tree ---------- */
.pow-tree { list-style: none; margin: 0; padding: 0; }
.pow-tree-node {
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--blue);
  border-radius: 0 var(--radius) var(--radius) 0;
  padding: 18px;
}
.pow-tree-num {
  display: inline-block;
  font: 600 0.66rem var(--font-mono);
  letter-spacing: 0.1em;
  color: var(--blue-deep);
  background: var(--tint);
  border: 1px solid var(--blue-soft);
  border-radius: 999px;
  padding: 3px 10px;
  margin-bottom: 8px;
}
.pow-tree-q { font: 600 1.05rem var(--font-display); color: var(--ink); margin: 0 0 4px; }
.pow-tree-q em { font-style: normal; color: var(--blue-deep); }
.pow-tree-p { font-size: 0.9rem; color: var(--ink-2); margin: 0 0 12px; max-width: 70ch; }
.pow-tree-branch { display: grid; gap: 8px; }
.pow-tree-no,
.pow-tree-yes {
  display: block;
  font-size: 0.88rem;
  text-decoration: none;
  padding: 9px 14px;
  border-radius: 9px;
  border: 1px solid;
  transition: transform 0.15s, box-shadow 0.2s, background 0.2s;
}
.pow-tree-no { color: var(--blue-deep); border-color: var(--blue-soft); background: var(--tint); }
.pow-tree-yes { color: #1c7a55; border-color: #bfe5d4; background: #eefaf4; }
.pow-tree-no::before { content: "→ "; font-weight: 700; }
.pow-tree-yes::before { content: "→ "; font-weight: 700; }
.pow-tree-no:hover,
.pow-tree-yes:hover { transform: translateX(3px); box-shadow: var(--shadow-1); }
.pow-tree-conn { width: 3px; height: 20px; margin-left: 14px; }
.pow-tree-conn span { display: block; width: 100%; height: 100%; background: var(--line-2); }
.pow-tree-final { border-left-color: var(--cyan); }
.pow-tree-final .pow-tree-num { color: #0b7285; background: #e6fbff; border-color: #9be8f5; }
.pow-tree-adv { margin-top: 12px; }
.pow-tree-adv summary {
  font: 500 0.8rem var(--font-mono);
  color: var(--blue-deep);
  cursor: pointer;
  padding: 8px 0;
}
.pow-tree-adv-in { border-left: 2px solid var(--line); padding: 4px 0 4px 14px; display: grid; gap: 8px; }
.pow-tree-adv-in p { font-size: 0.86rem; color: var(--ink-2); margin: 0; }

/* ---------- Power path diagram ---------- */
.pow-diagram {
  margin: 26px 0 0;
  background: var(--dark-2);
  border: 1px solid var(--dark-line);
  border-radius: 14px;
  padding: clamp(8px, 2vw, 18px);
}
.pow-diagram svg { width: 100%; height: auto; display: block; }
.pow-diagram figcaption { font-size: 0.82rem; color: var(--dark-muted); margin: 10px 6px 2px; max-width: 80ch; }

.pow-svg-label { fill: var(--dark-ink); font: 600 12px var(--font-mono); letter-spacing: 2px; }
.pow-svg-sub { fill: var(--dark-muted); font: 400 10px var(--font-mono); letter-spacing: 0.5px; }
.pow-svg-accent { fill: var(--cyan-bright); font: 600 13px var(--font-mono); letter-spacing: 1px; }
.pow-svg-status { fill: #5b7396; font: 400 10.5px var(--font-mono); letter-spacing: 1px; }
.pow-box { fill: #0e2038; stroke: #2e5f93; stroke-width: 1.5; }
.pow-bolt { fill: var(--cyan-bright); }
.pow-led { fill: var(--ok); }
.pow-cpu { fill: #122a48; stroke: #1e3a5f; stroke-width: 1.5; }
.pow-ram { fill: #122a48; stroke: var(--cyan-bright); stroke-width: 1.2; opacity: 0.9; }
.pow-pwr { fill: none; stroke: var(--cyan-bright); stroke-width: 1.5; }
.pow-screen { fill: #122a48; stroke: #1e3a5f; stroke-width: 1.5; }
.pow-trace { stroke: #24466f; stroke-width: 2; }
.pow-flow { stroke: var(--cyan-bright); stroke-width: 2.4; stroke-dasharray: 12 60; opacity: 0.85; }
.pow-flow-b { stroke-dasharray: 12 50; }
.pow-flow-c { stroke-dasharray: 12 40; }
.pow-via { fill: #24466f; }
.pow-glow { animation: powglow 7s ease-in-out infinite alternate; transform-box: fill-box; transform-origin: center; }
@keyframes powglow { from { opacity: 0.6; } to { opacity: 1; transform: scale(1.04); } }
@keyframes powflow { to { stroke-dashoffset: -72; } }
@keyframes powflowB { to { stroke-dashoffset: -62; } }
@keyframes powflowC { to { stroke-dashoffset: -52; } }
@keyframes powled { 0%, 100% { opacity: 1; } 50% { opacity: 0.35; } }
.pow-flow { animation: powflow 2.2s linear infinite; }
.pow-flow-b { animation: powflowB 2.6s linear infinite 0.4s; }
.pow-flow-c { animation: powflowC 2s linear infinite 0.8s; }
.pow-led { animation: powled 1.8s ease-in-out infinite; }

/* ---------- Risk badges ---------- */
.pow-risk {
  display: inline-block;
  font: 600 0.68rem var(--font-mono);
  letter-spacing: 0.05em;
  border-radius: 999px;
  padding: 4px 11px;
  border: 1px solid;
  white-space: nowrap;
}
.pow-risk-safe { color: #1c7a55; background: #eefaf4; border-color: #bfe5d4; }
.pow-risk-low { color: #8a5b12; background: #fdf6e9; border-color: #eed9b0; }
.pow-risk-pro { color: #8a3d12; background: #fdefe7; border-color: #f0c4a8; }
.pow-risk-never { color: #a12d2d; background: #fdecec; border-color: #efbcbc; }

/* ---------- Mistakes list ---------- */
.pow-mistakes { counter-reset: powm; list-style: none; margin: 0; padding: 0; display: grid; gap: 12px; }
.pow-mistakes li {
  counter-increment: powm;
  position: relative;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 15px 16px 15px 54px;
  font-size: 0.92rem;
  color: var(--ink-2);
}
.pow-mistakes li::before {
  content: counter(powm, decimal-leading-zero);
  position: absolute;
  left: 16px; top: 15px;
  font: 600 0.74rem var(--font-mono);
  color: #a12d2d;
}
.pow-mistakes li strong { color: var(--ink); }

/* ---------- Checklist ---------- */
.pow-check { background: var(--surface); border: 1px solid var(--line); border-radius: var(--radius); padding: 20px; box-shadow: var(--shadow-1); }
.pow-check-file { display: flex; justify-content: space-between; font-size: 0.72rem; color: var(--ink-3); border-bottom: 1px dashed var(--line-2); padding-bottom: 10px; margin: 0 0 12px; }
.pow-check-list { list-style: none; margin: 0; padding: 0; }
.pow-check-list li label {
  display: flex;
  gap: 12px;
  align-items: flex-start;
  padding: 9px 8px;
  border-radius: 8px;
  cursor: pointer;
  font-size: 0.92rem;
  color: var(--ink-2);
  transition: background 0.15s;
}
.pow-check-list li label:hover { background: #f6f9fd; }
.pow-check-list input { width: 17px; height: 17px; margin-top: 2px; accent-color: var(--blue); flex: none; }
.pow-check-list input:checked + span { color: var(--ink); }
.pow-check-actions { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; margin-top: 14px; padding-top: 14px; border-top: 1px solid var(--line); }
.pow-check-hint { font-size: 0.68rem; color: var(--ink-3); margin: 0; }

/* ---------- FAQ ---------- */
.pow-faq { display: grid; gap: 10px; }
.pow-faq-item { background: var(--surface); border: 1px solid var(--line); border-radius: 10px; transition: border-color 0.2s; }
.pow-faq-item[open] { border-color: var(--blue-soft); }
.pow-faq-item summary {
  cursor: pointer;
  list-style: none;
  padding: 14px 16px;
  font: 600 0.95rem var(--font-body);
  color: var(--ink);
  position: relative;
  padding-right: 38px;
}
.pow-faq-item summary::-webkit-details-marker { display: none; }
.pow-faq-item summary::after {
  content: "+";
  position: absolute;
  right: 16px; top: 50%;
  transform: translateY(-50%);
  font: 500 1.1rem var(--font-mono);
  color: var(--blue-deep);
  transition: transform 0.2s;
}
.pow-faq-item[open] summary::after { transform: translateY(-50%) rotate(45deg); }
.pow-faq-in { padding: 0 16px 14px; font-size: 0.92rem; color: var(--ink-2); }

/* ---------- Related ---------- */
.pow-related { display: grid; grid-template-columns: 1fr; gap: 12px; }
.pow-rel-card {
  display: block;
  background: var(--surface);
  border: 1px solid var(--line);
  border-radius: var(--radius);
  padding: 16px;
  text-decoration: none;
  color: var(--ink);
  transition: border-color 0.2s, transform 0.2s, box-shadow 0.2s;
}
.pow-rel-card:hover,
.pow-rel-card:focus-visible { border-color: var(--blue); transform: translateY(-2px); box-shadow: var(--shadow-1); }
.pow-rel-card h3 { font-size: 0.98rem; margin: 0 0 4px; }
.pow-rel-card p { font-size: 0.84rem; color: var(--ink-2); margin: 0 0 8px; }
.pow-rel-tag { font-size: 0.66rem; color: var(--blue-deep); text-transform: uppercase; letter-spacing: 0.08em; }
@media (min-width: 560px) { .pow-related { grid-template-columns: 1fr 1fr; } }
@media (min-width: 900px) { .pow-related { grid-template-columns: repeat(3, 1fr); } }

/* ---------- Local footer ---------- */
.pow-foot { border-top: 1px solid var(--line); background: var(--surface); }
.pow-foot-in {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
  padding: 18px 0;
}
.pow-foot-brand { font-size: 0.74rem; color: var(--ink-3); letter-spacing: 0.08em; }
.pow-foot-links { display: flex; gap: 18px; flex-wrap: wrap; }
.pow-foot-links a { font-size: 0.82rem; color: var(--ink-2); text-decoration: none; }
.pow-foot-links a:hover { color: var(--blue-deep); text-decoration: underline; }

/* ---------- Dark theme overrides ---------- */
[data-theme="dark"] .pow-art-sum:hover { background: #14213a; }
[data-theme="dark"] .pow-check-list li label:hover { background: #14213a; }
[data-theme="dark"] .pow-tree-yes { color: #7ee2b8; border-color: #1e4d3a; background: #0d2a1f; }
[data-theme="dark"] .pow-tree-final .pow-tree-num { color: #7ee2f5; background: #0d2a33; border-color: #1e4d5c; }
[data-theme="dark"] .pow-risk-safe { color: #7ee2b8; background: #0d2a1f; border-color: #1e4d3a; }
[data-theme="dark"] .pow-risk-low { color: #f5c97a; background: #2a2110; border-color: #5c4a1e; }
[data-theme="dark"] .pow-risk-pro { color: #f5a57a; background: #2a180d; border-color: #5c3a1e; }
[data-theme="dark"] .pow-risk-never { color: #f58a8a; background: #2a0d0d; border-color: #5c1e1e; }
[data-theme="dark"] .pow-mistakes li::before { color: #f58a8a; }
[data-theme="dark"] .pow-diagram { border-color: #24406b; }
[data-theme="dark"] .pow-figure img { border-color: var(--line); }
[data-theme="dark"] .pow-foot { background: #0d192e; }

/* ---------- Reduced motion ---------- */
@media (prefers-reduced-motion: reduce) {
  .pow-flow,
  .pow-led,
  .pow-glow { animation: none !important; }
  .pow-flow { opacity: 0.3; }
  .pow-progress > span { transition: none; }
  .pow-art-panel,
  .pow-art-inner { transition: none !important; }
  .pow-diag-opt,
  .pow-most-card,
  .pow-tree-no,
  .pow-tree-yes,
  .pow-rel-card { transition: none; }
}