:root {
  --bg-color: #fafafa;
  --text-color: #333;
  --text-light-color: #555;
  --text-muted-color: #aaa;
  --link-color: #777;
  --link-hover-color: #333;
  --border-color: #f0f0f0;
  --line-color: #e0e0e0;
  --dot-color: #e0e0e0;
  --underline-color: #ddd;

  --color-oaat: #95ab80d4;
  --color-esse: #424753d6;
  --color-rewords: #604b86da;
  --color-bbr: #e86a26dd;
}

.dark-mode {
  --bg-color: #111;
  --text-color: #eee;
  --text-light-color: #bbb;
  --text-muted-color: #777;
  --link-color: #aaa;
  --link-hover-color: #fff;
  --border-color: #222;
  --line-color: #333;
  --dot-color: #333;
  --underline-color: #444;
}

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

body {
  font-family:
    'Montserrat',
    -apple-system,
    BlinkMacSystemFont,
    'Segoe UI',
    Roboto,
    Helvetica,
    Arial,
    sans-serif;
  background-color: var(--bg-color);
  color: var(--text-color);
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 3rem 1rem;
  overflow-x: hidden;
  transition:
    background-color 0.5s ease,
    color 0.5s ease;
}

.container {
  width: 100%;
  max-width: 52rem;
  margin: 0 auto;
  text-align: center;
  opacity: 0;
  transition: opacity 2s ease;
}

header {
  margin-bottom: 4rem;
}

.logo-container {
  display: inline-block;
  position: relative;
}

h1 {
  font-size: 4rem;
  font-weight: 900;
  letter-spacing: 0.05em;
  position: relative;
  transition: color 0.5s ease;
}

.eye {
  position: relative;
  display: inline-block;
}

.dot {
  position: absolute;
  top: 21%;
  left: 50%;
  transform: translate(-50%, 0);
  font-size: 2.7rem;
  font-weight: 700;
  opacity: 1;
  transition: color 0.2s ease;
}

main {
  margin-bottom: 4rem;
}

.content {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  margin-bottom: 3rem;
}

.line {
  width: 3rem;
  height: 1px;
  background-color: var(--line-color);
  opacity: 0.4;
  transition:
    all 0.7s ease,
    background-color 0.5s ease;
}

p {
  font-size: 1rem;
  font-weight: 300;
  line-height: 1.6;
  letter-spacing: 0.05em;
  color: var(--text-light-color);
  max-width: 32rem;
  margin: 0 auto;
  font-style: italic;
  transition: color 0.5s ease;
}

.apps-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.25rem;
  margin: 0 auto 3rem;
}

.app-card {
  padding: 1.6rem;
  border: 2px solid var(--border-color);
  border-radius: 12px;
  text-align: left;
  transition: border-color 0.5s ease;
}

.app-card.oaat {
  border-color: var(--color-oaat);
}
.app-card.esse {
  border-color: var(--color-esse);
}
.app-card.rewords {
  border-color: var(--color-rewords);
}
.app-card.bbr {
  border-color: var(--color-bbr);
}

.app-title {
  font-size: 1.1rem;
  font-weight: 400;
  letter-spacing: 0.05em;
  color: var(--text-color);
  margin-bottom: 0.75rem;
  font-style: normal;
  transition: color 0.5s ease;
}

.app-description {
  font-size: 0.85rem;
  font-weight: 300;
  line-height: 1.5;
  color: var(--text-light-color);
  margin-bottom: 1.25rem;
  font-style: normal;
}

.app-link {
  font-size: 0.85rem;
  font-weight: 300;
  letter-spacing: 0.05em;
}

.email-container {
  padding-top: 2rem;
  transition: border-color 0.5s ease;
}

a {
  font-size: 1rem;
  font-weight: 200;
  letter-spacing: 0.1em;
  color: var(--link-color);
  text-decoration: none;
  transition: color 0.5s ease;
  position: relative;
  display: inline-block;
}

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

.underline {
  position: absolute;
  bottom: -1px;
  left: 0;
  width: 0;
  height: 1px;
  background-color: var(--underline-color);
  transition:
    width 0.7s ease,
    background-color 0.5s ease;
}

footer {
  padding: 1rem 0;
}

.copyright {
  font-size: 0.6rem;
  font-weight: 200;
  color: var(--text-muted-color);
  font-style: normal;
  transition: color 0.5s ease;
}

@media (min-width: 640px) {
  h1 {
    font-size: 4rem;
  }
}

@media (max-width: 560px) {
  .apps-grid {
    grid-template-columns: 1fr;
  }

  .app-card {
    text-align: center;
  }
}