:root {
  --color-teal-darkest: #0c2f2d;
  --color-teal-dark: #0e3b38;
  --color-teal: #145e58;
  --color-green: #1d5b3a;
  --color-green-dark: #143f28;
  --color-cyan: #5fd6d6;
  --color-cyan-light: #a9eaea;
  --color-yellow: #e7e62a;
  --color-white: #ffffff;
  --color-text: #15241f;
  --color-text-muted: #4a5a55;
  --color-bg: #f5fbfa;
  --color-border: #d9ece9;

  --font-heading: 'Poppins', sans-serif;
  --font-body: 'Inter', sans-serif;

  --radius: 14px;
  --shadow: 0 10px 30px rgba(12, 47, 45, 0.12);
}

* { box-sizing: border-box; }

html, body {
  margin: 0;
  padding: 0;
  font-family: var(--font-body);
  color: var(--color-text);
  background: var(--color-bg);
  scroll-behavior: smooth;
}

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

h1, h2, h3, h4 {
  font-family: var(--font-heading);
  color: var(--color-green-dark);
  line-height: 1.2;
  margin: 0 0 0.6em;
}

p { line-height: 1.65; color: var(--color-text-muted); }

a { color: var(--color-teal); text-decoration: none; }

.container {
  width: 100%;
  max-width: 1140px;
  margin: 0 auto;
  padding: 0 24px;
}

/* Header */
.site-header {
  background: var(--color-teal-darkest);
  border-bottom: 1px solid rgba(255, 255, 255, 0.08);
  position: sticky;
  top: 0;
  z-index: 50;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: 12px 24px;
}

.brand-logo { height: 52px; }

.main-nav {
  display: flex;
  align-items: center;
  gap: 22px;
}

.main-nav a {
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.92rem;
  color: var(--color-cyan-light);
  padding: 6px 2px;
  border-bottom: 2px solid transparent;
}

.main-nav a.is-active,
.main-nav a:hover {
  color: var(--color-white);
  border-bottom-color: var(--color-cyan);
}

.nav-cta {
  background: var(--color-yellow);
  color: var(--color-green-dark) !important;
  padding: 10px 18px !important;
  border-radius: 100px;
  border-bottom: none !important;
}
.nav-cta:hover { background: #f1f04f; }

.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}
.nav-toggle span {
  width: 26px;
  height: 3px;
  background: var(--color-white);
  border-radius: 2px;
}

/* Buttons */
.btn {
  display: inline-block;
  font-family: var(--font-heading);
  font-weight: 600;
  padding: 13px 26px;
  border-radius: 100px;
  transition: transform 0.15s ease, background 0.15s ease;
}
.btn-primary {
  background: var(--color-yellow);
  color: var(--color-green-dark);
}
.btn-primary:hover { background: #f1f04f; transform: translateY(-1px); }
.btn-outline {
  background: transparent;
  border: 2px solid var(--color-white);
  color: var(--color-white);
}
.btn-outline:hover { background: rgba(255,255,255,0.12); }

/* Hero */
.hero {
  background: var(--color-teal-darkest);
  color: var(--color-white);
  overflow: hidden;
}
.hero-banner {
  width: 100%;
  line-height: 0;
}
.hero-banner-img {
  width: 100%;
  height: auto;
  display: block;
}
.hero-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  flex-wrap: wrap;
  padding: 28px 24px;
}
.badge {
  display: inline-block;
  background: var(--color-yellow);
  color: var(--color-green-dark);
  font-family: var(--font-heading);
  font-weight: 700;
  font-size: 0.78rem;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  padding: 6px 14px;
  border-radius: 100px;
  margin-bottom: 16px;
}
.hero-meta {
  display: flex;
  gap: 28px;
  flex-wrap: wrap;
}
.meta-item { display: flex; flex-direction: column; }
.meta-label {
  font-size: 0.75rem;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: var(--color-cyan);
  margin-bottom: 4px;
}
.meta-value { font-weight: 600; font-family: var(--font-heading); }
.hero-actions { display: flex; gap: 14px; flex-wrap: wrap; }
.btn-outline-dark {
  background: transparent;
  border: 2px solid var(--color-cyan);
  color: var(--color-white);
}
.btn-outline-dark:hover { background: rgba(95, 214, 214, 0.15); }

/* Sections */
.section { padding: 72px 0; }
.section.alt { background: var(--color-white); }
.section h2 {
  font-size: 1.9rem;
  margin-bottom: 0.8em;
}

.about-grid {
  display: grid;
  grid-template-columns: 1.5fr 1fr;
  gap: 48px;
  align-items: start;
}

.info-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-left: 4px solid var(--color-cyan);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
}
.info-card h3 { font-size: 1.05rem; margin-top: 1.2em; }
.info-card h3:first-child { margin-top: 0; }
.info-card ul { padding-left: 1.2em; color: var(--color-text-muted); }
.info-card li { margin-bottom: 6px; }

.topics-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: 16px;
}
.topic-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px;
  font-family: var(--font-heading);
  font-weight: 600;
  color: var(--color-green-dark);
  border-top: 4px solid var(--color-green);
  transition: transform 0.15s ease;
}
.topic-card:hover { transform: translateY(-3px); }

.cta-section {
  background: linear-gradient(120deg, var(--color-green) 0%, var(--color-teal-dark) 100%);
  color: var(--color-white);
  text-align: center;
}
.cta-inner h2 { color: var(--color-white); }
.cta-inner p { color: var(--color-cyan-light); max-width: 560px; margin: 0 auto 28px; }
.cta-inner .hero-actions { justify-content: center; }

/* Page hero (sub pages) */
.page-hero {
  background: linear-gradient(120deg, var(--color-teal-dark), var(--color-green-dark));
  color: var(--color-white);
  padding: 56px 0;
}
.page-hero h1 { color: var(--color-white); margin-bottom: 0.3em; }
.page-hero p { color: var(--color-cyan-light); max-width: 640px; }

/* Schedule */
.schedule-day { margin-bottom: 48px; }
.schedule-list { display: flex; flex-direction: column; gap: 14px; }
.schedule-item {
  display: grid;
  grid-template-columns: 120px 1fr;
  gap: 20px;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px 22px;
}
.schedule-time {
  font-family: var(--font-heading);
  font-weight: 700;
  color: var(--color-teal);
}
.schedule-item strong { font-family: var(--font-heading); color: var(--color-green-dark); }
.note { color: var(--color-text-muted); font-style: italic; }

/* Speakers */
.speakers-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(160px, 1fr));
  gap: 24px;
  margin-bottom: 24px;
}
.speaker-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px;
  text-align: center;
}
.speaker-avatar {
  width: 100%;
  aspect-ratio: 1 / 1;
  border-radius: 50%;
  object-fit: cover;
  margin-bottom: 12px;
}
.speaker-card strong { display: block; font-family: var(--font-heading); color: var(--color-green-dark); }
.speaker-card span { font-size: 0.85rem; color: var(--color-text-muted); }

/* Committees */
.committee-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 16px;
}
.committee-card {
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 18px 20px;
}
.committee-card.highlight {
  background: var(--color-green);
  border-color: var(--color-green);
}
.committee-card.highlight strong,
.committee-card.highlight span { color: var(--color-white); }
.committee-card strong { display: block; font-family: var(--font-heading); color: var(--color-green-dark); margin-bottom: 4px; }
.committee-card span { font-size: 0.88rem; color: var(--color-text-muted); }

.two-col {
  display: grid;
  grid-template-columns: 1.4fr 1fr;
  gap: 48px;
  align-items: start;
}

.sponsor-grid {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  margin-top: 16px;
}
.sponsor-logo { width: 200px; border-radius: 10px; }

/* Steps */
.steps { padding-left: 1.2em; color: var(--color-text-muted); }
.steps li { margin-bottom: 10px; line-height: 1.6; }

/* Contact form */
.contact-form {
  display: flex;
  flex-direction: column;
  gap: 16px;
  background: var(--color-white);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 28px;
  box-shadow: var(--shadow);
}
.contact-form label {
  display: flex;
  flex-direction: column;
  gap: 6px;
  font-family: var(--font-heading);
  font-weight: 600;
  font-size: 0.9rem;
  color: var(--color-green-dark);
}
.contact-form input,
.contact-form textarea {
  font-family: var(--font-body);
  font-size: 1rem;
  padding: 11px 14px;
  border: 1px solid var(--color-border);
  border-radius: 8px;
  background: var(--color-bg);
  resize: vertical;
}
.contact-form input:focus,
.contact-form textarea:focus {
  outline: 2px solid var(--color-cyan);
  border-color: var(--color-cyan);
}
.contact-form button { align-self: flex-start; border: none; cursor: pointer; }

/* Footer */
.site-footer {
  background: var(--color-teal-darkest);
  color: var(--color-cyan-light);
}
.footer-inner {
  display: grid;
  grid-template-columns: 1.4fr 1fr 1fr 1fr;
  gap: 32px;
  padding: 56px 0 32px;
}
.footer-logo { height: 56px; margin-bottom: 12px; filter: brightness(1.1); }
.footer-brand p { color: var(--color-cyan-light); margin: 0; }
.footer-col h4 {
  color: var(--color-white);
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  margin-bottom: 14px;
}
.footer-col a, .footer-col p {
  display: block;
  color: var(--color-cyan-light);
  margin-bottom: 10px;
  font-size: 0.92rem;
}
.footer-col a:hover { color: var(--color-yellow); }
.footer-bottom {
  border-top: 1px solid rgba(255,255,255,0.1);
  padding: 18px 0;
  font-size: 0.82rem;
  color: rgba(169, 234, 234, 0.6);
}
.footer-bottom-inner {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  flex-wrap: wrap;
}
.footer-credit {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-white);
  color: var(--color-text-muted) !important;
  font-size: 0.78rem;
  font-weight: 500;
  padding: 6px 12px;
  border-radius: 100px;
}
.footer-credit:hover { color: var(--color-text) !important; }
.footer-credit-logo { height: 16px; width: auto; }

/* Responsive */
@media (max-width: 880px) {
  .about-grid, .two-col { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr 1fr; }
}

@media (max-width: 720px) {
  .nav-toggle { display: flex; }
  .main-nav {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: var(--color-teal-darkest);
    flex-direction: column;
    align-items: flex-start;
    padding: 16px 24px;
    gap: 14px;
    border-bottom: 1px solid rgba(255, 255, 255, 0.08);
    display: none;
  }
  .main-nav.is-open { display: flex; }
  .nav-cta { align-self: flex-start; }
  .schedule-item { grid-template-columns: 1fr; }
  .footer-inner { grid-template-columns: 1fr; }
}