:root {
  --primary: #593d3b;
}

* {
  padding: 0;
  margin: 0;
  box-sizing: border-box;
  font-family: "Poppins", sans-serif;
}

/* ****** nav ******** */

.navigation {
  background-color: var(--primary);
  color: #fff;
  padding: 1rem 1.5rem;
  font-size: 1.5rem;
  font-weight: 600;
}

/* ***** footer ****** */

footer {
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  width: 100%;
  margin-top: 3rem;
  font-size: 2rem;
  font-weight: 300;
  background-color: var(--primary);
  padding: 0.5rem;
  text-align: center;
  color: white;
}

.footer-links {
  display: inline-block;
  color: #fff;
  padding: 0 1rem 0;
  text-decoration: none;
  font-size: 2rem;
}

.footer-links:hover {
  transform: scale(1.05);
}

.footer-name {
  font-size: 1.2rem;
  padding: 0.5rem;
  font-weight: 500;
}

/* **** others **** */
body {
  background-image: url("hero.jpg");
  background-size: 100vw 100vh;
  object-fit: cover;
  background-repeat: no-repeat;
}
.container {
  max-width: 900px;
  text-align: center;
  margin: 2.5rem auto;
}

.head {
  font-size: 2rem;
  padding: 1rem;
  margin-bottom: 2rem;
  font-weight: 700;
}

#bday-input {
  font-size: 1rem;
  padding: 0.8rem 2rem;
  margin-bottom: 2rem;
  border-radius: 0.5rem;
  border: 2px solid var(--primary);
}

#show-btn {
  display: block;
  margin: 1rem auto 2rem;
  padding: 0.5rem 2rem;
  font-size: 1rem;
  font-weight: 500;
  color: #fff;
  background-color: var(--primary);
  border: none;
  border-radius: 0.3rem;
  letter-spacing: 0.3px;
}

#show-btn:hover,
#is-triangle-btn:hover {
  background-color: #593d3bda;
}

#result {
  text-align: center;
  font-size: 1.5rem;
  font-weight: 500;
  padding-top: 0.5rem;
}