*, *::before, *::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

/* ---- Theme ---- */

:root {
  --bg: #f8f7f4;
  --text: #1a1d23;
  --text-secondary: #5a5f68;
  --muted: #8a8f98;
  --wave: #1c2d3f;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --bg: #0a0e14;
    --text: #c8d0dc;
    --text-secondary: #8a95a4;
    --muted: #4e5a68;
    --wave: #c8d8e8;
  }
}

[data-theme="dark"] {
  --bg: #0a0e14;
  --text: #c8d0dc;
  --text-secondary: #8a95a4;
  --muted: #4e5a68;
  --wave: #c8d8e8;
}

html {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", sans-serif;
  background: var(--bg);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  max-width: 640px;
  margin: 0 auto;
  padding: 0 24px;
}

::selection {
  background: var(--wave);
  color: var(--bg);
}

a:focus-visible {
  outline: 2px solid var(--wave);
  outline-offset: 4px;
  border-radius: 2px;
}

/* ---- Navigation ---- */

nav {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 40px 0;
}

nav a {
  color: var(--text);
  text-decoration: none;
  font-size: 14px;
  letter-spacing: 0.03em;
  transition: opacity 0.2s;
}

nav a:hover {
  opacity: 0.5;
}

.wordmark {
  font-weight: 500;
  font-size: 15px;
  letter-spacing: 0.05em;
}

.nav-right {
  display: flex;
  align-items: center;
  gap: 20px;
}

/* ---- Theme Toggle ---- */

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  color: var(--text);
  padding: 4px;
  display: flex;
  align-items: center;
  transition: opacity 0.2s;
}

.theme-toggle:hover {
  opacity: 0.5;
}

.theme-toggle circle {
  fill: transparent;
  transition: fill 0.3s;
}

[data-theme="dark"] .theme-toggle circle {
  fill: currentColor;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) .theme-toggle circle {
    fill: currentColor;
  }
}

/* ---- Home ---- */

.home {
  min-height: calc(100vh - 120px);
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 48px;
  padding-bottom: 80px;
}

.hero {
  width: 100%;
  display: flex;
  justify-content: center;
}

.hero svg {
  width: 100%;
  max-width: 480px;
  height: auto;
  color: var(--wave);
}

.tagline {
  font-size: 16px;
  color: var(--text-secondary);
  letter-spacing: 0.01em;
  text-align: center;
}

/* ---- About ---- */

.about {
  max-width: 520px;
  padding: 60px 0 120px;
}

.about p {
  font-size: 17px;
  line-height: 1.75;
  margin-bottom: 28px;
}

.about .lead {
  font-size: 19px;
  line-height: 1.6;
  margin-bottom: 40px;
}

.about .muted {
  color: var(--muted);
  font-size: 15px;
}

/* ---- Responsive ---- */

@media (max-width: 600px) {
  body {
    padding: 0 20px;
  }

  nav {
    padding: 28px 0;
  }

  .hero svg {
    max-width: 340px;
  }

  .home {
    gap: 36px;
    padding-bottom: 60px;
  }

  .about {
    padding: 40px 0 80px;
  }

  .about p {
    font-size: 16px;
  }

  .about .lead {
    font-size: 17px;
  }
}