:root {
  color-scheme: light;
  --primary: #0b57d0;
  --on-primary: #ffffff;
  --secondary-container: #c2e7ff;
  --on-secondary-container: #001d35;
  --surface: #ffffff;
  --on-surface: #1f1f1f;
  --on-surface-variant: #444746;
  --surface-container-low: #f8fafd;
  --surface-container: #f0f4f9;
  --surface-container-high: #e9eef6;
  --outline: #747775;
  --outline-variant: #c4c7c5;
  --brand-font: "Google Sans", Roboto, "Segoe UI", Arial, sans-serif;
  --plain-font: "Google Sans Text", "Google Sans", Roboto, "Segoe UI", Arial, sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root {
    color-scheme: dark;
    --primary: #a8c7fa;
    --on-primary: #062e6f;
    --secondary-container: #004a77;
    --on-secondary-container: #c2e7ff;
    --surface: #131314;
    --on-surface: #e3e3e3;
    --on-surface-variant: #c4c7c5;
    --surface-container-low: #1b1b1b;
    --surface-container: #1e1f20;
    --surface-container-high: #282a2c;
    --outline: #8e918f;
    --outline-variant: #444746;
  }
}

* {
  box-sizing: border-box;
}

html {
  background: var(--surface);
}

body {
  margin: 0;
  background: var(--surface);
  color: var(--on-surface);
  font-family: var(--plain-font);
  font-size: 16px;
  line-height: 24px;
  letter-spacing: 0.5px;
  -webkit-font-smoothing: antialiased;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

.top-app-bar {
  position: sticky;
  top: 0;
  z-index: 1;
  background: var(--surface);
  border-bottom: 1px solid var(--outline-variant);
}

.top-app-bar-content {
  max-width: 840px;
  margin: 0 auto;
  padding: 0 24px;
  height: 64px;
  display: flex;
  align-items: center;
}

.site-name {
  font-family: var(--brand-font);
  font-size: 22px;
  line-height: 28px;
  font-weight: 400;
}

main {
  flex: 1;
  width: 100%;
  max-width: 840px;
  margin: 0 auto;
  padding: 0 24px 48px;
}

.hero {
  padding: 48px 0 32px;
}

h1 {
  font-family: var(--brand-font);
  font-size: 45px;
  line-height: 52px;
  font-weight: 400;
  letter-spacing: 0;
  margin: 0 0 16px;
}

.hero-lead {
  font-size: 22px;
  line-height: 28px;
  letter-spacing: 0;
  color: var(--on-surface-variant);
  margin: 0 0 24px;
  max-width: 640px;
}

.profile-links {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.chip {
  display: inline-flex;
  align-items: center;
  height: 32px;
  padding: 0 16px;
  border: 1px solid var(--outline);
  border-radius: 8px;
  color: var(--on-surface-variant);
  font-family: var(--brand-font);
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  letter-spacing: 0.1px;
  text-decoration: none;
  transition: background-color 150ms;
}

.chip:hover {
  background: color-mix(in srgb, var(--on-surface) 8%, transparent);
}

.chip:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

h2 {
  font-family: var(--brand-font);
  font-size: 24px;
  line-height: 32px;
  font-weight: 400;
  margin: 0 0 16px;
}

.paper-list {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: 16px;
}

.paper-card {
  background: var(--surface-container);
  border-radius: 16px;
  padding: 24px;
}

.paper-title {
  font-family: var(--brand-font);
  font-size: 22px;
  line-height: 28px;
  font-weight: 500;
  letter-spacing: 0;
  margin: 0 0 8px;
}

.paper-summary {
  color: var(--on-surface-variant);
  margin: 0 0 12px;
}

.paper-dates {
  font-size: 12px;
  line-height: 16px;
  font-weight: 500;
  letter-spacing: 0.5px;
  color: var(--on-surface-variant);
  margin: 0 0 20px;
}

.paper-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 8px;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  height: 40px;
  padding: 0 24px;
  border-radius: 20px;
  font-family: var(--brand-font);
  font-size: 14px;
  line-height: 20px;
  font-weight: 500;
  letter-spacing: 0.1px;
  text-decoration: none;
  transition: background-color 150ms, box-shadow 150ms;
}

.button-filled {
  background: var(--primary);
  color: var(--on-primary);
}

.button-filled:hover {
  box-shadow: 0 1px 2px rgba(0, 0, 0, 0.3), 0 1px 3px 1px rgba(0, 0, 0, 0.15);
}

.button-text {
  padding: 0 12px;
  color: var(--primary);
}

.button-text:hover {
  background: color-mix(in srgb, var(--primary) 8%, transparent);
}

.button:focus-visible {
  outline: 3px solid var(--primary);
  outline-offset: 2px;
}

.empty-state {
  background: var(--surface-container);
  border: 1px dashed var(--outline-variant);
  border-radius: 16px;
  padding: 32px 24px;
  text-align: center;
  color: var(--on-surface-variant);
  margin: 0;
}

footer {
  background: var(--surface-container-low);
  border-top: 1px solid var(--outline-variant);
  color: var(--on-surface-variant);
}

.footer-content {
  max-width: 840px;
  margin: 0 auto;
  padding: 24px;
  font-size: 12px;
  line-height: 16px;
  letter-spacing: 0.4px;
}

.footer-content p {
  margin: 0 0 8px;
}

.footer-content p:last-child {
  margin-bottom: 0;
}

@media (max-width: 600px) {
  .top-app-bar-content,
  main,
  .footer-content {
    padding-left: 16px;
    padding-right: 16px;
  }

  .hero {
    padding: 32px 0 24px;
  }

  h1 {
    font-size: 32px;
    line-height: 40px;
  }

  .hero-lead {
    font-size: 16px;
    line-height: 24px;
  }

  .paper-card {
    padding: 20px 16px;
  }
}