:root {
  --bg: #ffffff;
  --panel: #fbfbfd;
  --border: #e5e5ec;
  --text: #111111;
  --muted: #6a6a78;
  --purple: #6d4ae6;
  --purple-soft: rgba(109, 74, 230, 0.12);
  --shadow: 0 20px 55px rgba(17, 17, 17, 0.06);
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--text);
  font-family: "Avenir Next", "Segoe UI", Arial, sans-serif;
}

body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  background:
    radial-gradient(circle at top left, rgba(109, 74, 230, 0.08), transparent 32%),
    radial-gradient(circle at bottom right, rgba(17, 17, 17, 0.04), transparent 26%);
}

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

a {
  color: inherit;
}

span {
  color: var(--purple);
}

.page {
  position: relative;
  z-index: 1;
  width: min(1120px, calc(100vw - 32px));
  margin: 0 auto;
  padding: 34px 0 110px;
}

.home-hero {
  min-height: calc(100vh - 160px);
  display: flex;
  align-items: center;
}

.site-brand {
  display: flex;
  align-items: center;
  gap: 20px;
}

.logo {
  width: 92px;
  height: 92px;
  object-fit: contain;
  flex-shrink: 0;
}

.eyebrow {
  margin: 0 0 8px;
  color: var(--muted);
  text-transform: uppercase;
  letter-spacing: 0.16em;
  font-size: 0.74rem;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1,
h2 {
  font-family: Georgia, "Times New Roman", serif;
  line-height: 0.98;
  letter-spacing: -0.05em;
}

h1 {
  margin-bottom: 0;
  font-size: clamp(3rem, 9vw, 6.8rem);
}

h2 {
  margin-bottom: 0;
  font-size: clamp(1.8rem, 4vw, 3rem);
}

.intro,
.section p,
.person-card p,
.speaker-meta,
.speaker-summary {
  color: var(--muted);
  line-height: 1.6;
}

.intro {
  max-width: 46ch;
  font-size: 1.08rem;
  text-align: center;
  margin-top: 18px;
}

.section {
  padding: 22px 0 50px;
}

.section-header {
  display: grid;
  gap: 10px;
  margin-bottom: 20px;
}

.section-header.row {
  display: flex;
  justify-content: space-between;
  align-items: end;
  gap: 16px;
}

.pill {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 10px 14px;
  border-radius: 999px;
  border: 1px solid var(--border);
  background: linear-gradient(180deg, #fff, #fbfaff);
  color: var(--muted);
  margin: 0;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(12, minmax(0, 1fr));
  gap: 18px;
}

.person-card,
.empty-card {
  grid-column: span 4;
  border: 1px solid var(--border);
  border-radius: 24px;
  background: linear-gradient(180deg, #fff, var(--panel));
  box-shadow: var(--shadow);
}

.speaker-card {
  grid-column: span 3;
  border: 1px solid var(--border);
  border-radius: 20px;
  background: linear-gradient(180deg, #fff, var(--panel));
  box-shadow: var(--shadow);
}

.speaker-card,
.empty-card {
  overflow: hidden;
}

.person-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
  padding: 32px 18px 28px;
}

.person-card img {
  width: 120px;
  height: 120px;
  border-radius: 50%;
  object-fit: cover;
  object-position: center 15%;
  margin-bottom: 16px;
  background: linear-gradient(135deg, #f4f2fb, #ffffff);
  flex-shrink: 0;
}

.speaker-card {
  display: grid;
  justify-items: center;
  text-align: center;
  padding: 14px 12px 16px;
}

.speaker-photo-link {
  display: block;
  width: 110px;
  height: 110px;
  border-radius: 50%;
  overflow: hidden;
  margin-bottom: 12px;
  flex-shrink: 0;
  box-shadow: 0 8px 20px rgba(17, 17, 17, 0.12);
}

.speaker-photo,
.speaker-avatar {
  width: 100%;
  height: 100%;
  object-fit: cover;
  background: linear-gradient(135deg, #f4f2fb, #ffffff);
}

.speaker-body,
.empty-card {
  padding: 18px;
}

.speaker-body {
  display: grid;
  gap: 10px;
}

.speaker-name,
.person-card h3 {
  margin-bottom: 4px;
}

.speaker-title {
  margin: 0;
  color: var(--text);
}

.speaker-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 10px;
  margin-top: 8px;
  justify-content: center;
}

.speaker-link {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 44px;
  padding: 0 16px;
  border-radius: 999px;
  border: 1px solid transparent;
  background: var(--purple);
  color: #ffffff;
  text-decoration: none;
  font-weight: 600;
}

.speaker-link.secondary {
  background: transparent;
  color: var(--text);
  border-color: var(--border);
}

.speaker-avatar {
  display: grid;
  place-items: center;
  border-radius: 50%;
  font-size: clamp(1.4rem, 4vw, 2rem);
  font-weight: 700;
  color: var(--purple);
}

.speaker-card:hover .speaker-photo-link {
  transform: translateY(-1px);
}

.tab-bar {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%);
  z-index: 100;
  display: flex;
  align-items: center;
  gap: 4px;
  padding: 4px;
  background: rgba(251, 251, 253, 0.92);
  border: 1px solid var(--border);
  border-radius: 16px;
  width: fit-content;
  box-shadow: 0 8px 32px rgba(17, 17, 17, 0.12);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
}

.tab-btn {
  padding: 8px 18px;
  border-radius: 12px;
  border: none;
  background: transparent;
  color: var(--muted);
  font-size: 0.875rem;
  font-weight: 500;
  cursor: pointer;
  text-decoration: none;
  font-family: "Avenir Next", "Segoe UI", Arial, sans-serif;
  transition: color 0.15s, background 0.15s;
}

.tab-btn:hover {
  color: var(--text);
  background: rgba(0, 0, 0, 0.04);
}

.tab-btn.active {
  background: #fff;
  color: var(--text);
  box-shadow: 0 1px 4px rgba(0, 0, 0, 0.08);
}

.tab-btn.youtube {
  color: var(--purple);
  margin-left: 6px;
}

.tab-btn.youtube:hover {
  background: var(--purple-soft);
}

.hidden {
  display: none;
}

.about-layout {
  padding: 48px 0 64px;
  max-width: 640px;
  margin: 0 auto;
}

.about-text {
  padding-top: 4px;
}

.founders-centered {
  max-width: 860px;
  margin: 0 auto;
  min-height: calc(100vh - 160px);
  display: flex;
  flex-direction: column;
  justify-content: center;
}

/* clickable speaker cards */
.speaker-card-link {
  cursor: pointer;
  transition: transform 0.15s, box-shadow 0.15s;
}

.speaker-card-link:hover {
  transform: translateY(-3px);
  box-shadow: 0 24px 48px rgba(17, 17, 17, 0.1);
}

.speaker-photo-wrap {
  width: 110px;
  height: 110px;
  border-radius: 50%;
  overflow: hidden;
  margin-bottom: 12px;
  box-shadow: 0 8px 20px rgba(17, 17, 17, 0.12);
  flex-shrink: 0;
}

.speaker-photo-wrap img,
.speaker-photo-wrap .speaker-avatar {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

/* speaker detail page */
.speaker-detail-page {
  padding: 36px 0 64px;
  max-width: 520px;
  margin: 0 auto;
}

.back-btn {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: none;
  border: none;
  color: var(--purple);
  font-size: 0.9rem;
  font-weight: 600;
  font-family: "Avenir Next", "Segoe UI", Arial, sans-serif;
  cursor: pointer;
  padding: 0 0 28px;
  letter-spacing: 0.01em;
}

.back-btn:hover {
  opacity: 0.75;
}

.detail-body {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 6px;
}

.detail-photo {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  object-fit: cover;
  box-shadow: 0 16px 40px rgba(17, 17, 17, 0.12);
  margin-bottom: 16px;
}

.detail-avatar {
  width: 160px;
  height: 160px;
  border-radius: 50%;
  background: var(--purple-soft);
  display: grid;
  place-items: center;
  font-size: 3rem;
  font-weight: 700;
  color: var(--purple);
  margin-bottom: 16px;
}

.detail-name {
  margin: 4px 0 0;
  font-size: clamp(1.6rem, 4vw, 2.4rem);
}

.detail-role {
  margin: 0;
  color: var(--muted);
  font-size: 1rem;
}

.detail-talk {
  margin: 4px 0 0;
  font-weight: 600;
  font-size: 1rem;
}

.detail-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 12px;
  margin-top: 20px;
}

.home-desc {
  color: var(--muted);
  line-height: 1.7;
  font-size: 1.05rem;
  margin-bottom: 20px;
}

.person-card--full {
  grid-column: span 12;
  flex-direction: row;
  align-items: flex-start;
  text-align: left;
  gap: 28px;
  padding: 28px 32px;
}

.person-card--full img {
  width: 110px;
  height: 110px;
  flex-shrink: 0;
  margin-bottom: 0;
}

.person-card-info {
  flex: 1;
}

.person-credentials {
  margin: 12px 0 0;
  padding: 0;
  list-style: none;
}

.person-credentials li {
  color: var(--muted);
  font-size: 0.88rem;
  line-height: 1.5;
  padding: 7px 0 7px 16px;
  border-top: 1px solid var(--border);
  position: relative;
}

.person-credentials li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 50%;
  transform: translateY(-50%);
  width: 5px;
  height: 5px;
  border-radius: 50%;
  background: var(--purple);
}

.founder-linkedin {
  display: inline-flex;
  align-items: center;
  margin-top: 14px;
  padding: 7px 16px;
  border-radius: 999px;
  border: 1px solid var(--border);
  color: var(--text);
  text-decoration: none;
  font-size: 0.85rem;
  font-weight: 500;
  transition: background 0.15s, color 0.15s;
}

.founder-linkedin:hover {
  background: var(--purple);
  color: #fff;
  border-color: var(--purple);
}


@media (max-width: 900px) {
  .person-card,
  .empty-card {
    grid-column: span 6;
  }

  .speaker-card {
    grid-column: span 4;
  }
}


@media (max-width: 640px) {
  .page {
    width: min(1120px, calc(100vw - 24px));
  }

  .logo {
    width: 64px;
    height: 64px;
  }

  .section-header.row {
    flex-direction: column;
    align-items: start;
  }

  .person-card,
  .speaker-card,
  .empty-card {
    grid-column: span 6;
  }
}