/* ========================================================================
   Mark Wright — Speaker Site
   Premium editorial / white + brand-blue theme
   ======================================================================== */

:root {
  /* Light theme surfaces */
  --bg: #ffffff;
  --bg-alt: #f3f7fa;
  --surface: #ffffff;

  /* Text */
  --ink: #10222f;
  --ink-soft: #3d5162;
  --muted: #5c7182;

  /* Brand blues (sampled from bankconfidential.com) */
  --accent: #1c6082;       /* deep teal-navy — primary accent on light surfaces */
  --accent-bright: #0f88b8; /* mid brand blue — hover / emphasis */
  --accent-light: #33acd6;  /* bright cyan — decorative, dark surfaces, tints */

  /* Dark surfaces (hero + contact band only) */
  --dark: #0c1720;
  --dark-2: #12232f;
  --on-dark: #f5f8fa;
  --on-dark-soft: #b9c9d3;

  --line: rgba(16, 34, 47, 0.1);
  --line-strong: rgba(16, 34, 47, 0.18);
  --shadow: rgba(16, 34, 47, 0.08);
  --header-scrolled-bg: rgba(255, 255, 255, 0.88);

  --serif: "Fraunces", Georgia, "Times New Roman", serif;
  --sans: "Inter", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;

  --container: 1180px;
  --radius: 3px;

  color-scheme: light;
}

/* ---------------- Dark theme ---------------- */

:root[data-theme="dark"] {
  --bg: #0a0d10;
  --bg-alt: #12181f;
  --surface: #12181f;

  --ink: #f2f5f8;
  --ink-soft: #b9c8d3;
  --muted: #8393a1;

  --accent: #33acd6;
  --accent-bright: #5ec3e6;
  --accent-light: #7cd2ee;

  --dark: #05070a;
  --dark-2: #0b1319;
  --on-dark: #f5f8fa;
  --on-dark-soft: #b9c9d3;

  --line: rgba(242, 245, 248, 0.1);
  --line-strong: rgba(242, 245, 248, 0.18);
  --shadow: rgba(0, 0, 0, 0.45);
  --header-scrolled-bg: rgba(10, 13, 16, 0.86);

  color-scheme: dark;
}

* { box-sizing: border-box; }
html { scroll-behavior: smooth; }

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

img { max-width: 100%; display: block; }

.skip-link {
  position: absolute;
  left: -9999px;
  top: 0;
  background: var(--accent);
  color: #fff;
  padding: 0.75rem 1.25rem;
  z-index: 999;
  font-weight: 600;
}
.skip-link:focus { left: 1rem; top: 1rem; }

a { color: inherit; text-decoration: none; }

:focus-visible {
  outline: 2px solid var(--accent-bright);
  outline-offset: 3px;
}

.container {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 32px;
}

.tm { font-size: 0.5em; vertical-align: super; }

.eyebrow {
  display: block;
  font-family: var(--sans);
  font-size: 0.75rem;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--accent);
  font-weight: 700;
  margin: 0 0 1rem;
}
.eyebrow-light { color: var(--accent-light); }

.grain {
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 500;
  opacity: 0.02;
  mix-blend-mode: multiply;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='120' height='120'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='2' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

/* ---------------- Header ---------------- */

.site-header {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 100;
  padding: 20px 0;
  transition: background 300ms ease, padding 300ms ease, border-color 300ms ease, box-shadow 300ms ease;
  border-bottom: 1px solid transparent;
}
.site-header.scrolled {
  background: var(--header-scrolled-bg);
  backdrop-filter: blur(14px) saturate(140%);
  -webkit-backdrop-filter: blur(14px) saturate(140%);
  padding: 14px 0;
  border-bottom: 1px solid var(--line);
  box-shadow: 0 8px 30px var(--shadow);
}

.header-inner {
  max-width: var(--container);
  margin: 0 auto;
  padding: 0 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.nav-cluster {
  display: flex;
  align-items: center;
  gap: 20px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
  cursor: pointer;
}
.brand-mark {
  width: 34px;
  height: 34px;
  border: 1.5px solid var(--accent-light);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--serif);
  font-size: 0.8rem;
  letter-spacing: 0.02em;
  color: var(--on-dark);
  background: var(--dark);
  transition: color 300ms ease, background 300ms ease;
}
.brand-name {
  font-family: var(--sans);
  font-size: 0.82rem;
  font-weight: 700;
  letter-spacing: 0.14em;
  color: var(--on-dark);
  transition: color 300ms ease;
}
.site-header.scrolled .brand-name { color: var(--ink); }
.site-header.scrolled .brand-mark { border-color: var(--accent); color: var(--accent); background: transparent; }

.main-nav {
  display: flex;
  align-items: center;
  gap: 32px;
}
.main-nav a {
  font-size: 0.85rem;
  color: var(--on-dark-soft);
  font-weight: 500;
  letter-spacing: 0.02em;
  transition: color 200ms ease;
  cursor: pointer;
}
.main-nav a:hover { color: var(--on-dark); }
.site-header.scrolled .main-nav a { color: var(--ink-soft); }
.site-header.scrolled .main-nav a:hover { color: var(--accent); }

.main-nav a.nav-cta {
  color: #fff;
  background: var(--accent);
  padding: 11px 22px;
  border-radius: var(--radius);
  font-weight: 600;
  transition: background 200ms ease, transform 200ms ease;
}
.main-nav a.nav-cta:hover { background: var(--accent-bright); color: #fff; transform: translateY(-1px); }
.site-header.scrolled .main-nav a.nav-cta { color: #fff; }

.theme-toggle {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 40px;
  height: 40px;
  flex: 0 0 auto;
  background: transparent;
  border: 1px solid rgba(245, 248, 250, 0.35);
  border-radius: 50%;
  cursor: pointer;
  color: var(--on-dark);
  transition: border-color 300ms ease, color 300ms ease, background 200ms ease;
}
.theme-toggle:hover { border-color: var(--accent-light); color: var(--accent-light); }
.site-header.scrolled .theme-toggle { border-color: var(--line-strong); color: var(--ink-soft); }
.site-header.scrolled .theme-toggle:hover { border-color: var(--accent); color: var(--accent); }

.theme-toggle svg { width: 18px; height: 18px; }
.theme-toggle .icon-moon { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-sun { display: none; }
:root[data-theme="dark"] .theme-toggle .icon-moon { display: block; }

.nav-toggle {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 44px;
  height: 44px;
  background: transparent;
  border: 1px solid rgba(245, 248, 250, 0.35);
  border-radius: var(--radius);
  cursor: pointer;
  transition: border-color 300ms ease;
}
.site-header.scrolled .nav-toggle { border-color: var(--line-strong); }
.nav-toggle span {
  display: block;
  width: 18px;
  height: 1px;
  background: var(--on-dark);
  margin: 0 auto;
  transition: transform 250ms ease, opacity 250ms ease, background 300ms ease;
}
.site-header.scrolled .nav-toggle span { background: var(--ink); }
.nav-toggle.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav-toggle.open span:nth-child(2) { opacity: 0; }
.nav-toggle.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* ---------------- Hero (kept dark for photographic impact) ---------------- */

.hero {
  position: relative;
  min-height: 100svh;
  display: flex;
  flex-direction: column;
  justify-content: flex-end;
  overflow: hidden;
  background: var(--dark);
}

.hero-media {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 54vh;
  z-index: 0;
}
.hero-media img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: 50% 22%;
  filter: grayscale(0.3) contrast(1.03) saturate(0.9);
  transform: scale(1.0);
}
.hero-media::before {
  content: "";
  position: absolute;
  inset: 0;
  z-index: 1;
  background: var(--accent);
  mix-blend-mode: color;
  opacity: 0.5;
  pointer-events: none;
}
.hero-scrim {
  position: absolute;
  inset: 0;
  z-index: 2;
  background: linear-gradient(180deg, rgba(12,23,32,0.08) 0%, rgba(12,23,32,0.08) 55%, rgba(12,23,32,0.65) 85%, var(--dark) 100%);
}
.hero-scrim::after {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(28,96,130,0.1) 0%, transparent 40%);
}

.hero-content {
  position: relative;
  z-index: 2;
  padding-bottom: clamp(64px, 12vh, 140px);
  padding-top: calc(54vh + 40px);
}

.hero-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.6rem, 7.2vw, 5.6rem);
  line-height: 1.02;
  margin: 0 0 1.25rem;
  color: var(--on-dark);
  max-width: 16ch;
  letter-spacing: -0.01em;
}

.hero-sub {
  font-size: clamp(1rem, 1.6vw, 1.2rem);
  color: var(--on-dark-soft);
  max-width: 46ch;
  margin: 0 0 2.25rem;
  font-weight: 300;
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 16px;
}

/* Desktop: split layout so the portrait isn't cropped to a sliver by a full-bleed wide cover */
@media (min-width: 901px) {
  .hero {
    justify-content: center;
  }
  .hero-media {
    top: 0;
    bottom: 0;
    left: 0;
    right: auto;
    height: auto;
    width: 62%;
    -webkit-mask-image: linear-gradient(90deg, black 0%, black 52%, transparent 88%);
    mask-image: linear-gradient(90deg, black 0%, black 52%, transparent 88%);
  }
  .hero-media img {
    object-position: 50% 12%;
    transform: scale(1.0);
  }
  .hero-scrim {
    background:
      linear-gradient(90deg, rgba(12,23,32,0.15) 0%, transparent 30%, transparent 70%, rgba(12,23,32,0.35) 100%),
      linear-gradient(180deg, rgba(12,23,32,0.12) 0%, transparent 26%, rgba(12,23,32,0.55) 84%, var(--dark) 100%);
  }
  .hero-content {
    max-width: 620px;
    margin-left: auto;
    margin-right: clamp(24px, 6%, 96px);
    text-align: left;
    padding-top: clamp(120px, 14vh, 180px);
    padding-bottom: clamp(60px, 8vh, 120px);
  }
}

/* Buttons */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  padding: 15px 30px;
  font-size: 0.88rem;
  font-weight: 600;
  letter-spacing: 0.03em;
  border-radius: var(--radius);
  cursor: pointer;
  border: 1px solid transparent;
  transition: background 220ms ease, color 220ms ease, border-color 220ms ease, transform 220ms ease, box-shadow 220ms ease;
  min-height: 48px;
}
.btn-primary {
  background: var(--accent-light);
  color: var(--dark);
  box-shadow: 0 8px 24px rgba(51, 172, 214, 0.18);
}
.btn-primary:hover { background: #5ec3e6; transform: translateY(-2px); }
.btn-ghost {
  background: transparent;
  color: var(--on-dark);
  border-color: rgba(245, 248, 250, 0.3);
}
.btn-ghost:hover { border-color: var(--accent-light); color: var(--accent-light); }
.btn-large { padding: 18px 40px; font-size: 0.92rem; margin-top: 2.5rem; }

/* Buttons on light surfaces */
.btn-on-light.btn-primary {
  background: var(--accent);
  color: #fff;
  box-shadow: 0 10px 26px rgba(28, 96, 130, 0.22);
}
.btn-on-light.btn-primary:hover { background: var(--accent-bright); }

/* ---------------- Credibility strip ---------------- */

.credibility {
  background: var(--bg-alt);
  border-bottom: 1px solid var(--line);
  padding: 44px 0;
}
.credibility-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  flex-wrap: wrap;
  gap: 28px;
}
.credibility-item {
  display: flex;
  flex-direction: column;
  gap: 4px;
  min-width: 140px;
}
.credibility-num {
  font-family: var(--serif);
  font-size: 2.2rem;
  color: var(--accent);
  line-height: 1;
}
.credibility-text {
  font-family: var(--serif);
  font-size: 1.15rem;
  color: var(--ink);
}
.credibility-label {
  font-size: 0.75rem;
  color: var(--muted);
  letter-spacing: 0.03em;
}
.credibility-divider {
  width: 1px;
  height: 36px;
  background: var(--line-strong);
}
@media (max-width: 900px) {
  .credibility-divider { display: none; }
}

/* ---------------- About ---------------- */

.about { padding: 150px 0; }
.about-grid {
  display: grid;
  grid-template-columns: 0.9fr 1.1fr;
  gap: 64px;
}
.about-heading h2 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.9rem, 3vw, 2.7rem);
  line-height: 1.15;
  margin: 0;
  color: var(--ink);
  position: sticky;
  top: 150px;
}
.about-body p {
  color: var(--ink-soft);
  font-size: 1.02rem;
  margin: 0 0 1.4rem;
}
.about-body .lede {
  font-family: var(--serif);
  font-size: 1.35rem;
  color: var(--ink);
  font-weight: 400;
  line-height: 1.5;
}
.about-body strong { color: var(--accent); font-weight: 600; }

@media (max-width: 860px) {
  .about-grid { grid-template-columns: 1fr; gap: 28px; }
  .about-heading h2 { position: static; }
  .about { padding: 90px 0; }
}

/* ---------------- Keynote ---------------- */

.keynote {
  background: var(--bg-alt);
  padding: 140px 0;
  border-bottom: 1px solid var(--line);
  position: relative;
}
.keynote::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 15% 0%, rgba(28,96,130,0.08), transparent 55%);
  pointer-events: none;
}
.keynote-title {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2.1rem, 4.4vw, 3.4rem);
  margin: 0 0 0.6rem;
  color: var(--ink);
}
.keynote-sub {
  color: var(--accent);
  font-size: 1.05rem;
  margin: 0 0 3.5rem;
  font-weight: 500;
  max-width: 50ch;
}
.keynote-grid {
  display: grid;
  grid-template-columns: 1.2fr 0.8fr;
  gap: 56px;
  align-items: start;
}
.keynote-copy p {
  color: var(--ink-soft);
  font-size: 1.05rem;
  margin: 0 0 1.75rem;
}
.keynote-points {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 14px;
}
.keynote-points li {
  position: relative;
  padding-left: 26px;
  color: var(--ink);
  font-size: 0.98rem;
}
.keynote-points li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0.55em;
  width: 12px;
  height: 1px;
  background: var(--accent);
}
.keynote-quote {
  background: var(--surface);
  border: 1px solid var(--line);
  border-left: 3px solid var(--accent);
  padding: 40px 32px;
  border-radius: var(--radius);
  box-shadow: 0 20px 50px var(--shadow);
}
.quote-mark { width: 40px; height: 30px; fill: var(--accent-light); margin-bottom: 16px; }
.keynote-quote p {
  font-family: var(--serif);
  font-size: 1.3rem;
  line-height: 1.45;
  color: var(--ink);
  margin: 0;
}

@media (max-width: 860px) {
  .keynote { padding: 80px 0; }
  .keynote-grid { grid-template-columns: 1fr; gap: 40px; }
}

/* ---------------- Why book ---------------- */

.why-book { padding: 140px 0; }
.why-book h2 { display: none; }
.why-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: var(--line);
  border: 1px solid var(--line);
  margin-top: 2rem;
}
.why-card {
  background: var(--surface);
  padding: 42px 32px;
  transition: background 250ms ease;
}
.why-card:hover { background: var(--bg-alt); }
.why-index {
  font-family: var(--serif);
  color: var(--accent-light);
  -webkit-text-stroke: 1px var(--accent);
  font-size: 0.95rem;
  display: block;
  margin-bottom: 24px;
}
.why-card h3 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: 1.25rem;
  margin: 0 0 12px;
  color: var(--ink);
}
.why-card p {
  color: var(--muted);
  font-size: 0.92rem;
  margin: 0;
}

@media (max-width: 980px) {
  .why-grid { grid-template-columns: repeat(2, 1fr); }
}
@media (max-width: 560px) {
  .why-grid { grid-template-columns: 1fr; }
  .why-book { padding: 80px 0; }
}

/* ---------------- Topics ---------------- */

.topics {
  padding: 120px 0 140px;
  background: var(--bg);
  border-bottom: 1px solid var(--line);
}
.topics h2 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  margin: 0 0 2.5rem;
  color: var(--ink);
}
.topics-list {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
}
.topics-list span {
  border: 1px solid var(--line-strong);
  padding: 12px 22px;
  border-radius: 999px;
  font-size: 0.88rem;
  color: var(--ink-soft);
  background: var(--bg-alt);
  transition: border-color 200ms ease, color 200ms ease, background 200ms ease;
}
.topics-list span:hover {
  border-color: var(--accent);
  color: var(--accent);
  background: rgba(28,96,130,0.06);
}

@media (max-width: 640px) { .topics { padding: 80px 0; } }

/* ---------------- Audiences ---------------- */

.audiences { padding: 140px 0; }
.audiences-grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 56px;
  align-items: start;
}
.audiences-grid h2 {
  font-family: var(--serif);
  font-weight: 400;
  font-size: clamp(1.8rem, 3vw, 2.4rem);
  line-height: 1.2;
  margin: 0 0 1.5rem;
  color: var(--ink);
}
.audiences-note { color: var(--ink-soft); font-size: 1rem; max-width: 42ch; }
.audiences-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 0;
  border-top: 1px solid var(--line);
}
.audiences-list li {
  padding: 18px 4px;
  border-bottom: 1px solid var(--line);
  font-size: 0.95rem;
  color: var(--ink);
}
.audiences-list li:nth-child(odd) { padding-right: 20px; }

@media (max-width: 860px) {
  .audiences { padding: 80px 0; }
  .audiences-grid { grid-template-columns: 1fr; gap: 32px; }
  .audiences-list { grid-template-columns: 1fr; }
}

/* ---------------- Contact (dark brand-blue band for contrast) ---------------- */

.contact {
  padding: 150px 0 130px;
  background: linear-gradient(160deg, var(--dark-2) 0%, var(--dark) 70%);
  position: relative;
  overflow: hidden;
}
.contact::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(ellipse at 50% 0%, rgba(51,172,214,0.16), transparent 60%);
  pointer-events: none;
}
.contact-inner { position: relative; text-align: center; }
.contact h2 {
  font-family: var(--serif);
  font-weight: 500;
  font-size: clamp(2rem, 4.4vw, 3.1rem);
  margin: 0 0 1.25rem;
  line-height: 1.15;
  color: var(--on-dark);
}
.contact-sub {
  color: var(--on-dark-soft);
  max-width: 52ch;
  margin: 0 auto 3.5rem;
  font-size: 1.02rem;
}
.contact-cards {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: rgba(245,248,250,0.12);
  border: 1px solid rgba(245,248,250,0.14);
  margin: 0 auto;
  max-width: 920px;
  text-align: left;
}
.contact-card {
  background: rgba(255,255,255,0.03);
  padding: 26px 24px;
  display: flex;
  flex-direction: column;
  gap: 6px;
  cursor: pointer;
  transition: background 220ms ease;
}
.contact-card:hover { background: rgba(255,255,255,0.07); }
.contact-label {
  font-size: 0.72rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--accent-light);
}
.contact-value {
  font-size: 0.92rem;
  color: var(--on-dark);
  word-break: break-word;
}

@media (max-width: 860px) {
  .contact { padding: 90px 0; }
  .contact-cards { grid-template-columns: 1fr 1fr; }
}
@media (max-width: 520px) {
  .contact-cards { grid-template-columns: 1fr; }
}

/* ---------------- Footer ---------------- */

.site-footer {
  padding: 56px 0;
  border-top: 1px solid var(--line);
  background: var(--bg);
}
.footer-inner {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 10px;
  text-align: center;
}
.footer-brand .brand-mark { background: transparent; border-color: var(--accent); color: var(--accent); }
.footer-brand .brand-name { color: var(--ink); }
.footer-tag, .footer-copy {
  color: var(--muted);
  font-size: 0.82rem;
  margin: 0;
}

/* ---------------- Reveal animation ---------------- */

.reveal {
  opacity: 0;
  transform: translateY(18px);
  animation: reveal-in 900ms cubic-bezier(0.16, 1, 0.3, 1) forwards;
}
.hero-title.reveal { animation-delay: 120ms; }
.hero-sub.reveal { animation-delay: 280ms; }
.hero-actions.reveal { animation-delay: 420ms; }
.eyebrow.reveal { animation-delay: 0ms; }

@keyframes reveal-in {
  to { opacity: 1; transform: translateY(0); }
}

.fade-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 800ms cubic-bezier(0.16,1,0.3,1), transform 800ms cubic-bezier(0.16,1,0.3,1);
}
.fade-up.in-view { opacity: 1; transform: translateY(0); }

/* ---------------- Mobile nav ---------------- */

@media (max-width: 900px) {
  .main-nav {
    position: fixed;
    top: 0;
    right: 0;
    height: 100vh;
    width: min(78vw, 340px);
    background: var(--dark-2);
    border-left: 1px solid rgba(245,248,250,0.1);
    flex-direction: column;
    align-items: flex-start;
    justify-content: center;
    gap: 28px;
    padding: 40px;
    transform: translateX(100%);
    transition: transform 320ms cubic-bezier(0.16,1,0.3,1);
    z-index: 90;
  }
  .main-nav.open { transform: translateX(0); }
  .main-nav a { font-size: 1.1rem; color: var(--on-dark-soft); }
  .main-nav a:hover { color: var(--on-dark); }
  .main-nav a.nav-cta { margin-top: 12px; }
  .site-header.scrolled .main-nav a { color: var(--on-dark-soft); }
  .site-header.scrolled .main-nav a:hover { color: var(--on-dark); }
  .nav-toggle { display: flex; }
}

.nav-backdrop {
  position: fixed;
  inset: 0;
  background: rgba(10,15,20,0.5);
  opacity: 0;
  pointer-events: none;
  transition: opacity 320ms ease;
  z-index: 80;
}
.nav-backdrop.open { opacity: 1; pointer-events: auto; }

/* ---------------- Mobile: centered layout ---------------- */

@media (max-width: 900px) {
  .hero-content { text-align: center; }
  .hero-title, .hero-sub { margin-left: auto; margin-right: auto; }
  .hero-actions { justify-content: center; }

  .credibility-inner { justify-content: center; text-align: center; }
  .credibility-item { align-items: center; }

  .about-heading, .about-body { text-align: center; }
  .about-heading h2 { margin-left: auto; margin-right: auto; }
  .about-body .lede, .about-body p { margin-left: auto; margin-right: auto; }

  .keynote { text-align: center; }
  .keynote-sub { margin-left: auto; margin-right: auto; }
  .keynote-copy p { margin-left: auto; margin-right: auto; }
  .keynote-points { justify-items: center; }
  .keynote-points li { padding-left: 0; text-align: left; display: inline-flex; align-items: baseline; gap: 8px; }
  .keynote-points li::before { position: static; margin-top: 0.55em; flex: 0 0 auto; }
  .keynote-quote { text-align: left; }
  .quote-mark { margin-left: auto; margin-right: auto; display: block; }

  .why-book, .topics, .audiences { text-align: center; }
  .why-card { text-align: center; }
  .why-card p { margin-left: auto; margin-right: auto; }
  .topics-list { justify-content: center; }
  .audiences-grid { text-align: center; }
  .audiences-grid h2, .audiences-note { margin-left: auto; margin-right: auto; }
  .audiences-list { text-align: center; }
  .audiences-list li:nth-child(odd) { padding-right: 4px; }

  .footer-brand { justify-content: center; }
}

/* ---------------- Desktop refinements ---------------- */

@media (min-width: 1400px) {
  .container { padding: 0 40px; }
  .header-inner { padding: 0 40px; }
}