:root {
  color-scheme: light;

  --heading: clamp(2rem, 4vw, 2.75rem);
  --subheading: 28px;
  --color-text: #111;
  --color-surface: #fff;
  --color-accent: #203b60;
  --color-talk-title: #c45a10;
  --color-border-accent: #203b60;
  --color-accent-surface: #eff3f8;
  --color-divider: #000;
  --content-width: 960px;
  --nav-width: 1200px;
  --sidebar-width: 260px;
  --normal: 1rem;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--color-surface);
  color: var(--color-text);
  font-family:
    InterVariable,
    Inter,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    Helvetica,
    Arial,
    sans-serif;
  font-size: var(--normal);
  line-height: 1.7;
}

a {
  color: #3d5fae;
  text-decoration-style: dashed;
  text-decoration-thickness: 1px;
  text-underline-offset: 4px;
}

nav a {
  color: var(--color-surface);
  text-decoration: none;
  text-decoration-style: solid;
}

a:hover {
  text-decoration-style: solid;
}

a:focus-visible {
  outline: 2px solid var(--color-text);
  outline-offset: 5px;
}

.site-header {
  background: var(--color-accent);
  color: var(--color-surface);
  border-bottom: 1px solid var(--color-accent);
}

.site-header a:focus-visible {
  outline-color: var(--color-surface);
}

nav {
  max-width: var(--nav-width);
  margin: auto;
  padding: 22px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
  font-size: 18px;
}

.site-name {
  font-weight: 650;
}

.nav-links {
  display: flex;
  flex-wrap: wrap;
  gap: 12px 24px;
}

.mobile-navigation {
  display: none;
}

.navigation-updated {
  display: none;
}

.mobile-footer {
  display: none;
}

.mobile-navigation > summary {
  cursor: pointer;
  padding: 0;
  list-style: none;
}

.mobile-navigation > summary::-webkit-details-marker {
  display: none;
}

.mobile-navigation > summary:focus-visible {
  outline: 2px solid var(--color-surface);
  outline-offset: 4px;
}

nav a[aria-current="page"] {
  font-weight: 650;
  text-decoration: underline;
}

.container {
  max-width: var(--content-width);
  margin: 0 auto;
  padding: 60px 32px 96px;
}

h1 {
  font-size: var(--heading);
  line-height: 1.2;
  letter-spacing: -0.035em;
  font-weight: 650;
  margin: 0 0 48px;
}

h2 {
  font-size: var(--subheading);
  line-height: 1.4;
  font-weight: 700;
  color: var(--color-text);
  margin: 0 0 16px;
}

h3 {
  font-size: var(--normal);
  line-height: 1.7;
  margin: 0 0 10px;
  font-weight: 650;
}

p {
  margin: 0 0 18px;
}

ul {
  padding-left: 24px;
}

li {
  margin-bottom: 8px;
}

.seminar-name {
  text-align: center;
  margin: 4px 0 56px;
}

.seminar-accent {
  color: var(--color-talk-title);
}

.site-name .seminar-accent {
  color: #e88a45;
}

.home-section + .home-section {
  margin-top: 56px;
  padding-top: 40px;
  border-top: 1px solid #dedede;
}

.home-section[aria-labelledby="how-to-follow"]
  + .home-section[aria-labelledby="how-to-contribute"] {
  margin-top: 32px;
  padding-top: 0;
  border-top: 0;
}

.home-section.next-talk-box {
  margin-top: 32px;
  border: 2px solid var(--color-border-accent);
  border-radius: 18px;
  padding: 28px;
  background-color: var(--color-accent-surface);
}

.confirmed-speaker p {
  margin: 0;
}

.next-talk-box p:last-child {
  margin-bottom: 0;
}

.next-talk-box + .home-section {
  margin-top: 32px;
  padding-top: 0;
  border-top: 0;
}

.home-section[aria-label="Introduction"]
  + .home-section[aria-labelledby="how-to-join"] {
  margin-top: 24px;
  padding-top: 0;
  border-top: 0;
}

.home-section[aria-labelledby="how-to-join"]
  + .home-section[aria-labelledby="home-contact"] {
  margin-top: 32px;
  padding-top: 0;
  border-top: 0;
}

.next-talk-box > h2,
.next-talk-more {
  text-align: center;
}

.next-talk-more {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem 1rem;
}

.next-talk-cards {
  display: grid;
  gap: 28px;
  margin: 28px 0;
  padding: 0;
  list-style: none;
}

.next-talk-card {
  display: grid;
  grid-template-columns: 7fr 3fr;
  align-items: start;
  gap: 0 24px;
  min-width: 0;
  margin: 0;
  text-align: center;
  overflow-wrap: anywhere;
}

.next-talk-card > h3 {
  margin-bottom: 6px;
  text-align: left;
}

.next-talk-info {
  text-align: left;
}

.next-talk-speaker {
  margin-bottom: 8px;
}

.next-talk-portrait {
  display: block;
  width: 180px;
  max-width: 100%;
  height: auto;
  margin: 0 auto;
}

.session + .session {
  margin-top: 40px;
  padding-top: 0;
}

.confirmed-speakers {
  margin-top: 40px;
}

.confirmed-speaker-list {
  list-style: none;
  padding: 0;
  margin: 24px 0 0;
  display: grid;
  grid-template-columns: repeat(
    auto-fit,
    minmax(min(100%, max(200px, calc((100% - 56px) / 3))), 1fr)
  );
  gap: 28px;
}

.confirmed-speaker {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  margin: 0;
  text-align: center;
  overflow-wrap: anywhere;
}

.confirmed-speaker h3 {
  margin-bottom: 2px;
}

.confirmed-speaker img {
  display: block;
  width: auto;
  max-width: min(100%, 180px);
  height: 180px;
  object-fit: cover;
}

.session-date,
.about-section > h2,
.resource-section > h2 {
  display: flex;
  align-items: center;
  gap: 20px;
}

.session-date::after,
.about-section > h2::after {
  content: "";
  flex: 1;
  min-width: 24px;
  height: 3pt;
  background: var(--color-divider);
}

.timezones {
  list-style: disc;
  padding-left: 24px;
  margin: 0 0 20px;
}

.session-links {
  list-style: none;
  padding-left: 0;
  margin: 0 0 20px;
}

.zoom-url,
.recording-url,
.session-url {
  min-width: 0;
  overflow-wrap: anywhere;
}

.session-links:empty {
  display: none;
}

.talk {
  display: grid;
  grid-template-columns: 7fr 3fr;
  gap: 0;
  padding-top: 0;
  margin-top: 24px;
}

.session > .talk:first-of-type {
  margin-top: 16px;
}

.talk-copy {
  padding-right: 36px;
  min-width: 0;
  overflow-wrap: anywhere;
}

.talk-title {
  grid-column: 1 / -1;
  color: var(--color-talk-title);
  font-size: 20px;
  font-weight: 700;
  line-height: 1.4;
}

.speaker-photo {
  padding-left: 24px;
}

.speaker-photo img {
  width: 100%;
  max-width: 320px;
  height: auto;
  display: block;
}

.text-block {
  margin-top: 24px;
}

.next-talk-info > .text-block {
  margin-top: 8px;
}

.without-photo {
  grid-template-columns: 1fr;
}

.announcements {
  margin-top: 26px;
}

.team-group + .team-group {
  margin-top: 32px;
}

.about-section,
.resource-section {
  overflow-wrap: anywhere;
}

.about-section + .about-section,
.resource-section + .resource-section {
  margin-top: 40px;
}

section[aria-labelledby="resources-contents"],
section[aria-labelledby="open-problems-contents"] {
  padding-bottom: 8px;
  border-bottom: 3pt solid var(--color-divider);
}

section[aria-labelledby="resources-contents"] + .resource-section,
section[aria-labelledby="open-problems-contents"] + .resource-section {
  margin-top: 24px;
}

.problem-status-box {
  width: fit-content;
  max-width: 100%;
  border: 2px solid currentcolor;
  border-radius: 6px;
  padding: 8px 12px;
  background-color: color-mix(in srgb, currentcolor 8%, white);
}

.problem-status-solved {
  color: #42734b;
}

.problem-status-open {
  color: #ad4936;
}

.problem-status-partially-solved {
  color: var(--color-talk-title);
}

.team-members {
  list-style: disc;
  padding-left: 24px;
  margin: 0;
}

.skip-link {
  position: absolute;
  z-index: 20;
  left: 16px;
  top: -100px;
  background: var(--color-surface);
  padding: 8px 16px;
}

.skip-link:focus {
  top: 8px;
}

@media (width > 1000px) {
  body {
    padding-left: var(--sidebar-width);
  }

  .site-header {
    position: fixed;
    inset: 0 auto 0 0;
    width: var(--sidebar-width);
    overflow-y: auto;
    border-bottom: 0;
  }

  nav {
    min-height: 100%;
    flex-direction: column;
    align-items: stretch;
    padding: 40px 24px;
    gap: 36px;
  }

  .site-name {
    line-height: 1.4;
  }

  .desktop-navigation {
    flex-direction: column;
    gap: 8px;
  }

  .navigation-updated {
    display: block;
    margin: auto 0 0;
    padding: 0 12px;
    font-size: 0.8rem;
    color: rgb(255 255 255 / 75%);
  }

  .desktop-navigation a {
    padding: 10px 12px;
    border-radius: 6px;
  }

  .desktop-navigation a:hover,
  .desktop-navigation a[aria-current="page"] {
    background: rgb(255 255 255 / 10%);
  }
}

@media (width <= 1000px) {
  body {
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    min-height: 100dvh;
  }

  main.container {
    width: 100%;
  }

  .mobile-footer {
    display: block;
    margin-top: auto;
    padding: 20px 24px;
    border-top: 1px solid #e5e7eb;
    color: #666;
    font-size: 0.8rem;
    text-align: center;
  }

  nav {
    display: grid;
    grid-template-columns: minmax(0, 1fr) auto;
    align-items: baseline;
    padding: 18px 24px;
    gap: 14px;
  }

  .site-name {
    min-width: 0;
  }

  .desktop-navigation {
    display: none;
  }

  .mobile-navigation {
    display: block;
    position: relative;
    justify-self: end;
  }

  .mobile-navigation .nav-links {
    position: absolute;
    top: calc(100% + 8px);
    right: -24px;
    z-index: 10;
    width: min(280px, calc(100vw - 48px));
    background: var(--color-accent);
    border-radius: 6px 0 0 6px;
    flex-direction: column;
    gap: 0;
    padding: 8px;
  }

  .mobile-navigation .nav-links a {
    padding: 10px 12px;
  }
}

@media (width <= 640px) {
  :root {
    --subheading: 24px;
  }

  .container {
    padding: 40px 24px 64px;
  }

  .seminar-name {
    margin: 0 0 40px;
  }

  .talk {
    grid-template-columns: 1fr;
  }

  .next-talk-card {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .talk-title {
    order: 0;
  }

  .talk > .talk-title,
  .next-talk-card > .talk-title,
  .speaker,
  .next-talk-speaker {
    text-align: center;
  }

  .next-talk-portrait,
  .speaker-photo {
    order: 1;
    margin-bottom: 16px;
  }

  .next-talk-info,
  .talk-copy {
    order: 2;
  }

  .home-section.next-talk-box {
    padding: 20px;
  }

  .talk-copy {
    padding-right: 0;
    text-align: left;
  }

  .speaker-photo {
    padding: 0;
  }

  .speaker-photo img {
    max-width: 220px;
    margin-inline: auto;
  }
}