/* CUT TO — Shared structure */

*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  font-size: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  margin: 0;
}

a {
  color: inherit;
  text-decoration: none;
}

a:hover {
  opacity: 0.6;
}

/* Full-screen hero */

.hero {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: clamp(2rem, 6vw, 4rem) clamp(1.5rem, 5vw, 3rem);
}

.hero__main {
  flex: 1;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
}

.hero__content {
  width: 100%;
  max-width: 40rem;
  display: flex;
  flex-direction: column;
  align-items: center;
}

.hero__rest {
  opacity: 0;
  transition: opacity 1s ease;
}

.hero__rest.is-visible {
  opacity: 1;
}

.hero__tagline-en {
  margin: clamp(2rem, 5vw, 3rem) 0 0.75rem;
  line-height: 1.4;
}

.hero__tagline-zh {
  margin: 0 0 clamp(2rem, 5vw, 3rem);
  line-height: 1.5;
}

.hero__intro {
  margin: 0 0 clamp(2.5rem, 5vw, 3.5rem);
  max-width: 32rem;
  line-height: 1.7;
}

.hero__status {
  margin: 0 0 1.75rem;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  font-size: 0.6875rem;
}

.hero__link {
  letter-spacing: 0.1em;
  text-transform: uppercase;
  font-size: 0.75rem;
  border-bottom: 1px solid currentColor;
  padding-bottom: 3px;
  transition: opacity 0.2s ease;
}

/* Footer */

.site-footer {
  text-align: center;
  padding-top: clamp(2rem, 5vw, 3rem);
}

.site-footer__heading {
  margin: 0 0 0.75rem;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.6875rem;
}

.site-footer p {
  margin: 0 0 0.35rem;
  font-size: 0.8125rem;
}

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

/* Opening Letter */

.letter-page {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  padding: clamp(2.5rem, 6vw, 4rem) clamp(1.5rem, 5vw, 3rem);
}

.letter-page__main {
  flex: 1;
  width: 100%;
  max-width: 34rem;
  margin-inline: auto;
}

.letter-page__back {
  display: inline-block;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  font-size: 0.6875rem;
  margin-bottom: clamp(2.5rem, 6vw, 3.5rem);
  transition: opacity 0.2s ease;
}

.letter-page__header {
  margin-bottom: clamp(2rem, 5vw, 2.5rem);
  padding-bottom: 1.75rem;
}

.letter-page__title {
  margin: clamp(1.5rem, 4vw, 2rem) 0 0.5rem;
  line-height: 1.2;
}

.letter-page__meta {
  margin: 0;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.6875rem;
}

.letter-page__body p {
  margin: 0 0 1.5rem;
  line-height: 1.75;
}

.letter-page__body p:last-child {
  margin-bottom: 0;
}

.letter-page__closing {
  margin-top: 2.5rem;
  padding-top: 1.75rem;
}

/* Version picker */

.picker {
  min-height: 100vh;
  min-height: 100dvh;
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
  text-align: center;
  padding: 2rem;
  gap: 2rem;
}

.picker__label {
  letter-spacing: 0.2em;
  text-transform: uppercase;
  font-size: 0.6875rem;
}

.picker__links {
  display: flex;
  flex-direction: column;
  gap: 1rem;
}

.picker__link {
  letter-spacing: 0.12em;
  text-transform: uppercase;
  font-size: 0.75rem;
  border-bottom: 1px solid currentColor;
  padding-bottom: 3px;
}