@font-face {
  font-family: 'LINE Seed JP';
  font-style: normal;
  font-display: swap;
  font-weight: 400;
  src: url(https://cdn.jsdelivr.net/fontsource/fonts/line-seed-jp@5.3.0/latin-400-normal.woff2) format('woff2'),
       url(https://cdn.jsdelivr.net/fontsource/fonts/line-seed-jp@5.3.0/latin-400-normal.woff) format('woff');
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}

@font-face {
  font-family: 'LINE Seed JP';
  font-style: normal;
  font-display: swap;
  font-weight: 700;
  src: url(https://cdn.jsdelivr.net/fontsource/fonts/line-seed-jp@5.3.0/latin-700-normal.woff2) format('woff2'),
       url(https://cdn.jsdelivr.net/fontsource/fonts/line-seed-jp@5.3.0/latin-700-normal.woff) format('woff');
  unicode-range: U+0000-00FF,U+0131,U+0152-0153,U+02BB-02BC,U+02C6,U+02DA,U+02DC,U+0304,U+0308,U+0329,U+2000-206F,U+20AC,U+2122,U+2191,U+2193,U+2212,U+2215,U+FEFF,U+FFFD;
}

:root {
  --bg: #fcfcfc;
  --fg: #4a515b;
  --heading: #1e2125;
  --nav-inactive: #8c95a1;
  --nav-active: #1e2125;
  --divider: #8c95a1;
  --link: #6b7787;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #111214;
    --fg: #b7bcc4;
    --heading: #f2f2f2;
    --nav-inactive: #6b7280;
    --nav-active: #f2f2f2;
    --divider: #4a515b;
    --link: #9aa4b2;
  }
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font-family: 'LINE Seed JP', system-ui, -apple-system, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  font-size: 16px;
  line-height: 1.75;
}

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

.layout {
  display: flex;
  flex-direction: column;
  max-width: 800px;
  margin: 0 auto;
  padding: 1.5rem;
}

.sidenav {
  width: 100%;
  margin-bottom: 1.5rem;
}

.sidenav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1.25rem;
  justify-content: flex-start;
}

.sidenav a {
  text-decoration: none;
  color: var(--nav-inactive);
  transition: color 0.15s ease;
}

.sidenav a:hover,
.sidenav a.active {
  color: var(--nav-active);
}

.divider {
  display: none;
}

main section {
  padding: 1.5rem 0;
}

main section:first-child {
  padding-top: 0;
}

main h1 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--heading);
  margin: 0 0 1rem;
}

main h2 {
  font-size: 1.15rem;
  font-weight: 600;
  color: var(--heading);
  margin: 0 0 1rem;
}

main h3 {
  font-size: 1rem;
  font-weight: 600;
  color: var(--heading);
  margin: 0 0 0.3rem;
}

main p {
  margin: 0 0 1rem;
}

.contact {
  margin-top: 1rem;
}

.project {
  margin-bottom: 1.5rem;
}

.project p {
  margin: 0;
}

.project .note {
  display: block;
  margin-top: 0.4rem;
  font-style: italic;
  font-size: 0.85em;
  color: var(--nav-inactive);
}

@media (min-width: 640px) {
  .layout {
    flex-direction: row;
    padding: 3.5rem 1.5rem;
    gap: 3rem;
  }

  .sidenav {
    width: 4rem;
    flex-shrink: 0;
    margin-bottom: 0;
  }

  .sidenav ul {
    flex-direction: column;
    align-items: flex-end;
    gap: 0.4rem;
    position: sticky;
    top: 3.5rem;
  }

  .divider {
    display: block;
    width: 1px;
    align-self: stretch;
    background: var(--divider);
    opacity: 0.5;
  }

  main {
    flex: 1;
    max-width: 42rem;
  }
}