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

:root {
  --bg: #ffffff;
  --text: #111111;
  --text-secondary: #666666;
  --border: #e0e0e0;
  --toggle-bg: #f0f0f0;
}

[data-theme="dark"] {
  --bg: #0a0a0a;
  --text: #f0f0f0;
  --text-secondary: #999999;
  --border: #222222;
  --toggle-bg: #1a1a1a;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  background-color: var(--bg);
  color: var(--text);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.3s ease, color 0.3s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.theme-toggle {
  position: fixed;
  top: 1.5rem;
  right: 1.5rem;
  background: var(--toggle-bg);
  border: 1px solid var(--border);
  border-radius: 50%;
  width: 2.5rem;
  height: 2.5rem;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.15rem;
  transition: background-color 0.3s ease, border-color 0.3s ease;
  z-index: 100;
  line-height: 1;
}

.theme-toggle:hover {
  border-color: var(--text-secondary);
}

.theme-toggle .icon-sun,
.theme-toggle .icon-moon {
  pointer-events: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
  display: inline;
}

[data-theme="dark"] .theme-toggle .icon-moon {
  display: none;
}

.theme-toggle .icon-sun {
  display: none;
}

.theme-toggle .icon-moon {
  display: inline;
}

main {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 2rem;
  text-align: center;
}

.logo {
  width: 90px;
  height: 90px;
  margin-bottom: 2rem;
  border-radius: 50%;
  transition: filter 0.3s ease;
}

[data-theme="dark"] .logo {
  filter: invert(1);
}

.brand {
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: 0.15em;
  text-transform: uppercase;
  margin-bottom: 0.75rem;
}

.tagline {
  font-size: 1.05rem;
  color: var(--text-secondary);
  font-weight: 400;
  max-width: 400px;
  line-height: 1.6;
  margin-bottom: 2.5rem;
}

.divider {
  width: 40px;
  height: 1px;
  background: var(--border);
  margin-bottom: 2.5rem;
  transition: background-color 0.3s ease;
}

.coming-soon {
  font-size: 0.8rem;
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--text-secondary);
  font-weight: 500;
}

footer {
  padding: 1rem 2rem;
  text-align: center;
  font-size: 0.75rem;
  color: var(--text-secondary);
  border-top: 1px solid var(--border);
  transition: border-color 0.3s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.6rem;
}

footer a {
  color: var(--text-secondary);
  text-decoration: none;
  transition: color 0.2s ease;
}

footer a:hover {
  color: var(--text);
}

footer .footer-sep {
  opacity: 0.4;
}

@media (max-width: 480px) {
  .brand {
    font-size: 1.35rem;
  }

  .tagline {
    font-size: 0.95rem;
  }

  .logo {
    width: 72px;
    height: 72px;
  }
}