/* ==========================================================================
   Interview questions (/interview-questions/*)
   Each topic page sets --iv-accent (from includes/interview_data.php) for its
   icon and number badges; everything else uses the site green palette.
   Fixed pixel sizing because the site root font-size is 62.5%.
   ========================================================================== */
.iv {
  --iv-bg: #f7faf9;
  --iv-ink: #0f172a;
  --iv-body: #334155;
  --iv-muted: #5b6b7c;
  --iv-line: #e2e8f0;
  --iv-green: #047857;
  --iv-green-deep: #065f46;
  --iv-mint: #ecfdf5;
  --iv-head: 'Bricolage Grotesque', 'Inter', system-ui, sans-serif;
  --iv-text: 'Inter', system-ui, sans-serif;
  --iv-mono: 'JetBrains Mono', 'DM Mono', ui-monospace, monospace;
  --iv-accent: #047857;
  background: var(--iv-bg);
  color: var(--iv-body);
  font: 400 16.5px/1.7 var(--iv-text);
  -webkit-font-smoothing: antialiased;
}
/* style.css sets overflow-x:hidden on html and body, which breaks sticky. */
html:has(main.iv), html:has(main.iv) body { overflow-x: clip; }
.iv *, .iv *::before, .iv *::after { box-sizing: border-box; }
.iv h1, .iv h2, .iv h3 { font-family: var(--iv-head); color: var(--iv-ink); letter-spacing: -0.02em; margin: 0; }
.iv p { margin: 0; }
.iv a:focus-visible, .iv button:focus-visible, .iv summary:focus-visible { outline: 3px solid #34d399; outline-offset: 3px; border-radius: 8px; }
.iv code { font: 500 0.88em var(--iv-mono); background: #eef2f6; color: #0f172a; padding: 2px 6px; border-radius: 6px; word-break: break-word; }
.iv-wrap { width: min(1200px, calc(100% - 32px)); margin: 0 auto; }

/* ---------------------------------------------------------------- hero */
.iv-hero {
  padding: 40px 0 28px;
  background:
    radial-gradient(60% 90% at 100% 0%, rgba(52, 211, 153, 0.18), transparent 60%),
    linear-gradient(180deg, #ecf8f1 0%, var(--iv-bg) 100%);
  border-bottom: 1px solid var(--iv-line);
}
.iv-crumbs { display: flex; flex-wrap: wrap; align-items: center; gap: 8px; font-size: 13.5px; color: var(--iv-muted); margin-bottom: 22px; }
.iv-crumbs a { color: var(--iv-green); text-decoration: none; font-weight: 600; }
.iv-crumbs a:hover { text-decoration: underline; }
.iv-crumbs i { font-size: 10px; opacity: .6; }
.iv-hero__row { display: flex; align-items: center; gap: 18px; }
.iv-hero__icon { flex: 0 0 auto; width: 64px; height: 64px; display: grid; place-items: center; border-radius: 18px; background: #fff;
  border: 1px solid var(--iv-line); box-shadow: 0 14px 30px -20px rgba(15, 23, 42, .45); color: var(--iv-accent); font-size: 32px; }
.iv-eyebrow { display: inline-flex; align-items: center; gap: 8px; font: 700 12.5px/1.4 var(--iv-text); letter-spacing: .08em; text-transform: uppercase; color: var(--iv-green); }
.iv-hero h1 { margin-top: 6px; font-size: clamp(28px, 4.2vw, 46px); font-weight: 800; line-height: 1.08; }
.iv-lede { margin-top: 18px; max-width: 760px; font-size: 17.5px; color: var(--iv-body); }
.iv-byline { margin-top: 10px; font-size: 13.5px; color: var(--iv-muted); }
.iv-levels { display: flex; flex-wrap: wrap; gap: 10px; margin-top: 24px; }
.iv-levels a, .iv-toggle { display: inline-flex; align-items: center; gap: 8px; padding: 9px 15px; border-radius: 999px; background: #fff; border: 1px solid var(--iv-line);
  font: 600 14px/1.2 var(--iv-text); color: var(--iv-ink); text-decoration: none; cursor: pointer; transition: border-color .2s ease, color .2s ease; }
.iv-levels a span { padding: 2px 8px; border-radius: 999px; background: var(--iv-mint); color: var(--iv-green-deep); font-size: 12px; }
.iv-levels a:hover, .iv-toggle:hover { border-color: var(--iv-green); color: var(--iv-green); }
.iv-toggle { background: var(--iv-ink); color: #fff; border-color: var(--iv-ink); }
.iv-toggle:hover { background: #1e293b; color: #fff; }

/* -------------------------------------------------------------- layout */
.iv-layout { display: grid; grid-template-columns: minmax(0, 1fr) 320px; gap: 36px; padding: 36px 0 56px; align-items: start; }
.iv-section { scroll-margin-top: 90px; }
.iv-section + .iv-section, .iv-inline-cta + .iv-section { margin-top: 40px; }
.iv-section > h2 { font-size: clamp(21px, 2.4vw, 26px); font-weight: 800; margin-bottom: 16px; }
.iv-section > h2::first-letter { text-transform: uppercase; }

/* -------------------------------------------------------------- Q&A */
.iv-q { margin-top: 12px; background: #fff; border: 1px solid var(--iv-line); border-radius: 16px; scroll-margin-top: 90px;
  transition: border-color .2s ease, box-shadow .2s ease; }
.iv-q[open] { border-color: #bbf7d0; box-shadow: 0 18px 40px -30px rgba(6, 78, 59, .5); }
.iv-q summary { display: flex; align-items: flex-start; gap: 14px; padding: 18px 20px; cursor: pointer; list-style: none; }
.iv-q summary::-webkit-details-marker { display: none; }
.iv-q__num { flex: 0 0 auto; min-width: 34px; height: 30px; padding: 0 6px; display: grid; place-items: center; border-radius: 9px;
  background: color-mix(in srgb, var(--iv-accent) 10%, #fff); color: color-mix(in srgb, var(--iv-accent) 70%, #000); font: 700 13px/1 var(--iv-mono); }
.iv-q h3 { flex: 1 1 auto; font: 700 17px/1.45 var(--iv-text); letter-spacing: -0.005em; color: var(--iv-ink); padding-top: 3px; }
.iv-q h3 code { font-size: .86em; }
.iv-q__chev { flex: 0 0 auto; margin-top: 8px; color: #94a3b8; font-size: 13px; transition: transform .2s ease; }
.iv-q[open] .iv-q__chev { transform: rotate(180deg); color: var(--iv-green); }
.iv-q summary:hover h3 { color: var(--iv-green-deep); }
.iv-a { padding: 0 20px 20px 68px; }
.iv-a > * + * { margin-top: 12px; }
.iv-a ul { margin: 12px 0 0; padding-left: 22px; list-style: disc; }
.iv-a li { display: list-item; }
.iv-a li + li { margin-top: 6px; }
.iv-a strong { color: var(--iv-ink); }
.iv-code { position: relative; border-radius: 12px; background: #0f172a; overflow: hidden; }
.iv-code__lang { position: absolute; top: 8px; right: 12px; font: 700 10.5px/1 var(--iv-mono); letter-spacing: .1em; color: #94a3b8; }
.iv-code pre { margin: 0; padding: 16px 18px; overflow-x: auto; }
.iv-code code { display: block; padding: 0; background: none; color: #e2e8f0; font: 500 13.5px/1.65 var(--iv-mono); white-space: pre; word-break: normal; }
.iv-tip { display: flex; gap: 10px; padding: 12px 14px; border-radius: 12px; background: #fffbeb; border: 1px solid #fde68a; font-size: 14.5px; color: #78350f; }
.iv-tip i { margin-top: 4px; color: #b45309; }
.iv-tip strong { color: #78350f; }

/* ---------------------------------------------------- inline course CTA */
.iv-inline-cta { display: flex; align-items: center; justify-content: space-between; gap: 18px; margin-top: 28px; padding: 20px 22px; border-radius: 18px;
  background: linear-gradient(135deg, #064e3b 0%, #047857 100%); color: #d1fae5; }
.iv-inline-cta strong { display: block; color: #fff; font: 800 18px/1.3 var(--iv-head); }
.iv-inline-cta span { font-size: 14.5px; }
.iv-inline-cta a { flex: 0 0 auto; display: inline-flex; align-items: center; gap: 8px; padding: 12px 18px; border-radius: 12px; background: #fff; color: var(--iv-green-deep);
  font-weight: 700; font-size: 14.5px; text-decoration: none; }
.iv-inline-cta a:hover { color: #064e3b; transform: translateY(-1px); }

/* -------------------------------------------------------------- sidebar */
.iv-side { position: sticky; top: 96px; display: grid; gap: 16px; }
.iv-card { padding: 20px; border-radius: 18px; background: #fff; border: 1px solid var(--iv-line); }
.iv-card__title { font-size: 17px; font-weight: 800; margin-bottom: 12px !important; }
.iv-course { display: block; padding: 14px; border-radius: 14px; border: 1px solid var(--iv-line); text-decoration: none; color: var(--iv-ink); transition: border-color .2s ease, transform .2s ease; }
.iv-course + .iv-course { margin-top: 10px; }
.iv-course:hover { border-color: var(--iv-green); color: var(--iv-ink); transform: translateY(-2px); }
.iv-course__type { display: block; font: 700 11.5px/1.4 var(--iv-text); letter-spacing: .08em; text-transform: uppercase; color: var(--iv-green); }
.iv-course strong { display: block; margin-top: 3px; font: 700 15.5px/1.35 var(--iv-text); }
.iv-course__price { display: inline-block; margin-top: 6px; font: 800 17px/1 var(--iv-head); color: #064e3b; }
.iv-card--links ul { margin: 0; padding: 0; list-style: none; }
.iv-card--links li + li { margin-top: 4px; }
.iv-card--links a { display: flex; align-items: center; gap: 10px; padding: 9px 10px; border-radius: 10px; color: var(--iv-ink); text-decoration: none; font-size: 15px; font-weight: 600; }
.iv-card--links a:hover { background: var(--iv-mint); color: var(--iv-green-deep); }
.iv-card--links i { width: 18px; color: var(--iv-green); text-align: center; }

/* ---------------------------------------------------------- more topics */
.iv-more { padding: 48px 0; background: #fff; border-top: 1px solid var(--iv-line); }
.iv-more h2 { font-size: clamp(22px, 2.6vw, 28px); font-weight: 800; margin-bottom: 20px; }
.iv-more__grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(220px, 1fr)); gap: 12px; }
.iv-more__card { display: flex; align-items: center; gap: 12px; padding: 16px 18px; border-radius: 14px; border: 1px solid var(--iv-line); background: var(--iv-bg);
  color: var(--iv-ink); font-weight: 700; font-size: 15px; text-decoration: none; transition: border-color .2s ease, transform .2s ease; }
.iv-more__card i { font-size: 22px; color: var(--iv-accent); }
.iv-more__card:hover { border-color: var(--iv-accent); color: var(--iv-ink); transform: translateY(-2px); }

/* ------------------------------------------------------------------ hub */
.iv-hub { padding: 36px 0 56px; }
.iv-hub__grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(300px, 1fr)); gap: 18px; }
.iv-hub__card { display: flex; flex-direction: column; gap: 10px; padding: 24px; border-radius: 20px; background: #fff; border: 1px solid var(--iv-line);
  text-decoration: none; color: var(--iv-body); transition: border-color .2s ease, transform .2s ease, box-shadow .2s ease; }
.iv-hub__card:hover { border-color: var(--iv-accent); color: var(--iv-body); transform: translateY(-3px); box-shadow: 0 22px 44px -32px rgba(15, 23, 42, .5); }
.iv-hub__icon { width: 52px; height: 52px; display: grid; place-items: center; border-radius: 14px; background: color-mix(in srgb, var(--iv-accent) 10%, #fff); color: var(--iv-accent); font-size: 26px; }
.iv-hub__card h2 { font-size: 21px; font-weight: 800; }
.iv-hub__card p { font-size: 15px; }
.iv-hub__meta { margin-top: auto; display: flex; align-items: center; justify-content: space-between; padding-top: 8px; font-size: 14px; font-weight: 700; color: var(--iv-green); }
.iv-hub__meta span:first-child { color: var(--iv-muted); font-weight: 600; }
.iv-howto { padding: 0 0 56px; }
.iv-howto__box { padding: 28px; border-radius: 22px; background: #fff; border: 1px solid var(--iv-line); }
.iv-howto__box h2 { font-size: clamp(21px, 2.4vw, 26px); font-weight: 800; margin-bottom: 14px; }
.iv-howto__box ol { margin: 0; padding-left: 22px; }
.iv-howto__box li + li { margin-top: 8px; }

/* ----------------------------------------------------------- responsive */
@media (max-width: 991.98px) {
  .iv-layout { grid-template-columns: 1fr; }
  .iv-side { position: static; grid-template-columns: repeat(auto-fit, minmax(260px, 1fr)); }
}
@media (max-width: 575.98px) {
  .iv-hero__icon { width: 52px; height: 52px; font-size: 26px; border-radius: 14px; }
  .iv-q summary { padding: 16px; gap: 10px; }
  .iv-q h3 { font-size: 16px; }
  .iv-a { padding: 0 16px 18px; }
  .iv-inline-cta { flex-direction: column; align-items: flex-start; }
}
@media (prefers-reduced-motion: reduce) {
  .iv-q, .iv-q__chev, .iv-course, .iv-more__card, .iv-hub__card { transition: none; }
}