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

:root {
  --bg-color: #ffffff;
  --text-primary: #000000;
  --text-secondary: #666666;
  --logo-filter: none;
}

[data-theme="dark"] {
  --bg-color: #000000;
  --text-primary: #ffffff;
  --text-secondary: #999999;
  --logo-filter: invert(1);
}

body {
  font-family: "Noto Sans Mono", monospace;
  background-color: var(--bg-color);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  transition: background-color 0.3s ease, color 0.3s ease;
}

.header {
  display: flex;
  align-items: center;
  padding: 1.5rem 2rem;
  position: relative;
}

.logo-container {
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  align-items: center;
}

.logo {
  width: 80px;
  height: 80px;
  border: 3px solid var(--text-primary);
  border-radius: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: var(--bg-color);
  transition: border-color 0.3s ease;
}

.logo svg {
  width: 40px;
  height: 40px;
  filter: var(--logo-filter);
  transition: filter 0.3s ease;
}

.theme-toggle {
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color 0.3s ease;
  margin-left: auto;
}

.theme-toggle:hover {
  background-color: rgba(128, 128, 128, 0.1);
}

.logo-container svg {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  transition: opacity 0.3s ease;
}

.logo-light {
  opacity: 1;
}

.logo-container svg:not(.logo-light) {
  opacity: 0;
}

[data-theme="dark"] .logo-light {
  opacity: 0;
}

[data-theme="dark"] .logo-container svg:not(.logo-light) {
  opacity: 1;
}

.theme-toggle i {
  font-size: 24px;
  color: var(--text-primary);
  transition: color 0.3s ease;
}

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

.title {
  font-size: 2.5rem;
  font-weight: 600;
  margin-bottom: 1rem;
  color: var(--text-primary);
}

.subtitle {
  font-size: 1.2rem;
  font-weight: 400;
  color: var(--text-secondary);
}

@media (max-width: 768px) {
  .header {
    padding: 1rem 1.5rem;
  }

  .logo {
    width: 60px;
    height: 60px;
  }

  .logo svg {
    width: 30px;
    height: 30px;
  }

  .title {
    font-size: 2rem;
  }

  .subtitle {
    font-size: 1rem;
  }
}