:root {
  color-scheme: light dark;
  --black: #000;
  --border-radius: 5px;
  --box-shadow: 0 2px 5px rgba(0, 0, 0, 0.1);
  --font-family: 'Nunito Sans', sans-serif;
  --font-size: 20px;
  --line-height: 1.6;
  --margin: 0 auto;
  --max-width: 1200px;
  --padding: 1rem;
  --primary-color: #206F6F;
  --secondary-color: #34abab;
  --stripe-color: #A9E5E5;
  --tertiary-color: #60D2D2;
  --text-color: #131313;
  --white: #fff;
}

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

body {
  color: var(--text-color);
  font-family: var(--font-family);
  font-size: var(--font-size);
  line-height: var(--line-height);
  margin: 0;
}

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

a:focus,
a:hover,
.menu-toggle:focus {
  outline: var(--primary-color) solid 2px;
  outline-offset: 3px;
  position: relative;
}

.container {
  margin: 0 auto;
  max-width: 1000px;
  padding: 0 1rem;
}

h2,
h3 {
  margin: 4rem 0 2rem;
}

h2 {
  font-size: 2.5rem;
}

h3 {
  font-size: 1.5rem;
  margin-top: 2rem;
}

section h2+p+div {
  padding-top: 1.3rem;
}

section p a {
  font-weight: bold;
  text-decoration: underline;
}

.skip-link,
.sr-only {
  position: absolute;
  white-space: nowrap;
}

.skip-link {
  clip: rect(1px, 1px, 1px, 1px);
  clip-path: inset(50%);
  height: 1em;
  overflow: hidden;
  width: 1em;
}

.skip-link:focus {
  background: var(--tertiary-color);
  clip: auto;
  clip-path: none;
  color: var(--black);
  height: auto;
  left: 0;
  outline: none;
  padding: 0.625em;
  top: 0;
  width: auto;
  z-index: 1000;
}

.sr-only {
  border: 0;
  clip: rect(0, 0, 0, 0);
  height: 1em;
  margin: -1em;
  overflow: hidden;
  padding: 0;
  width: 1em;
}

section {
  padding: 4rem 0;
}

/* Navbar */
.navbar {
  background-color: var(--white);
  padding: 1rem 0;
  width: 100%;
}

.nav-container {
  align-items: center;
  display: flex;
  justify-content: space-between;
  margin: 0 auto;
  max-width: 1000px;
  padding: 0 1rem;
}

/* Menu links */
.menu-toggle {
  background: none;
  border: none;
  color: var(--text-color);
  cursor: pointer;
  display: none;
  font-size: 1em;
  font-weight: bold;
}

.nav-menu {
  display: flex;
  list-style: none;
  margin: 0;
  padding: 0;
}

.nav-menu a {
  color: var(--text-color);
  display: inline-block;
  font-size: var(--font-size);
  font-weight: 600;
  text-decoration: none;
  transition: font-size 0.5s ease;
  width: 100%;
}

.nav-menu li {
  margin-left: 1.5rem;
}

/* Hero */
.hero {
  background-color: var(--primary-color);
  color: var(--white);
  overflow: hidden;
  padding: 6rem 1rem;
  text-align: center;
}

.hero .container {
  align-items: center;
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
}

.hero .hero-left,
.hero .hero-right {
  box-sizing: border-box;
  flex: 1 1 300px;
}

.hero .hero-left {
  padding-right: 2rem;
}

.hero h1 {
  font-size: 3.5rem;
  line-height: 1.2;
  margin: 0 0 0.5rem;
}

.hero h1 span {
  display: block;
  font-family: "Indie Flower", cursive;
  font-size: 2.5rem;
}

.hero p {
  font-size: 1.25rem;
}

.hero .hero-right {
  background: rgba(255, 255, 255, 0.1);
  border-radius: 8px;
  padding: 2rem;
  position: relative;
}

.hero .hero-right img {
  height: auto;
  border-radius: 8px;
  max-width: 100%;
}

.hero ul {
  align-items: center;
  display: flex;
  font-weight: bold;
  flex-direction: column;
  list-style: none;
  padding: 0;
}

.hero ul img {
  margin-right: 0.5rem;
}

.hero li {
  align-items: center;
  display: flex;
  font-size: 1.3rem;
  margin-bottom: 0.75rem;
  width: 80%;
}

.hero li .date-time {
  display: flex;
  flex-wrap: wrap;
  gap: 0.5rem;
}

header a {
  color: var(--white);
  margin-left: 0.5rem;
  text-decoration: underline;
}

/* Agenda Table */
table {
  border-collapse: collapse;
  margin-top: 1rem;
  width: 100%;
}

th,
td {
  border: 1px solid var(--tertiary-color);
  padding: 1rem;
  text-align: left;
}

th {
  background-color: var(--secondary-color);
  color: var(--black);
}

tr:nth-child(even) {
  background-color: var(--stripe-color);
}

/* Team */
.team-grid {
  display: grid;
  gap: 2rem;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  padding-top: 1.3rem;
}

.team-member {
  text-align: center;
}

.team-member img {
  border-radius: 50%;
  height: 250px;
  object-fit: cover;
  width: 250px;
}

/* Speakers */

#speakers h3 {
  margin-bottom: 0;
}

#speakers .sub {
  font-size: 1rem;
  margin-block-start: 0;
}

/* Sponsors */
.sponsor-item a {
  display: inline-block;
  line-height: 0;
}

.sponsor-item img {
  height: auto;
  width: 250px;
}

img[alt="Keynoa"] {
  width: 150px
}

.sponsor-list {
  display: grid;
  font-size: 1rem;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  margin-top: 1rem;
}

.btn {
  background: var(--tertiary-color);
  border: 0.188em solid var(--tertiary-color);
  border-radius: 5.625em;
  color: var(--text-color);
  display: inline-block;
  font-weight: bold;
  margin: .5em 0 2.5em;
  padding: 0.625em 1.25em;
  text-decoration: none;
  transition: background 0.3s ease;
}

.btn:hover,
.btn:focus {
  border: 0.188em solid var(--primary-color);
}

.video-container:focus-within {
  border: 0.188em solid var(--black) !important;
}

/* SDGs */
.sdg-section {
  background-color: #f9f9f9;
  margin-top: 2.5rem;
  padding: 1rem 2rem 2rem;
  text-align: center;
}

.sdg-section h2 {
  font-size: 2rem;
  margin-bottom: 0.5rem;
}

.sdg-section p {
  margin: 0 auto 2rem;
  max-width: 600px;
}

.sdg-grid {
  display: grid;
  gap: 1.5rem;
  grid-template-columns: repeat(auto-fit, minmax(150px, 1fr));
}

.sdg-item img {
  height: auto;
  margin-bottom: 0.5rem;
  max-width: 200px;
}

.sdg-item h3 {
  font-size: 1.2rem;
  margin: 0.5rem 0;
}

.sdg-item p {
  color: var(--text-color);
  font-size: 1.125rem;
}

.sdg-note {
  color: var(--text-color);
  font-size: 1rem;
  margin-top: 2rem;
}

/* Footer */
footer {
  background-color: var(--tertiary-color);
  color: var(--black);
  margin-top: 5rem;
  padding: 2.5rem 0;
  text-align: center;
}

footer > div:not(.container) {
  background-color: var(--white);
  padding: 25px;
}

footer a {
  color: var(--black);
}

footer p > a {
  text-decoration: solid underline var(--black) 2px;
}

footer a:focus, footer a:hover {
  outline-color: var(--black);
}

footer .to-the-top {
  align-items: center;
  border-top: 1px solid var(--secondary-color);
  display: flex;
  justify-content: space-between;
  margin-top: 2.5rem;
  padding-top: 2rem;
  text-align: right;
}

footer .to-the-top-long {
  display: inline;
}

footer .to-the-top-short {
  display: none;
}

@media (max-width: 56.25em) {

  /* 900px */
  .menu-toggle {
    display: block;
    order: 2;
  }

  .nav-container {
    flex-wrap: wrap;
  }

  .nav-menu {
    display: none;
    flex-direction: column;
    order: 3;
    width: 100%;
  }

  .nav-menu.active {
    display: flex;
  }

  .nav-menu li {
    margin: 0.625em 0;
  }
}

@media (max-width: 768px) {

  .hero .hero-right::before {
    display: none;
  }
}

@media (max-width: 30em) {

  /* 480px */
  footer .to-the-top-long {
    display: none;
  }

  footer .to-the-top-short {
    display: inline;
  }
}

@media (prefers-color-scheme: dark) {

  section#speakers, section#about, section#agenda h2, section#sponsors > :not(section#sponsors .sponsor-list, section#sponsors .btn), section#team {
    color: var(--white);
  }

  .sponsor-list {
    background: #f9f9f9;
  }

  tr:nth-child(odd) {
    color: var(--white);
  }

  footer {
    color: var(--text-color);
  }

  a {
    color: var(--secondary-color);
  }
}

.video-container {
  position: relative;
  padding-bottom: 56.25%;
  height: 0;
  overflow: hidden;
  max-width: 100%;
}

.video-container iframe {
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
}