body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
    background: #f9f9f9;
    color: #333;
  }
  header {
    background: #0074D9;
    color: white;
    padding: 1rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
  }
  .site-title {
    font-size: 1.2rem;
  }
  
.nav-bar {
    background: #0074D9;
    display: none; /* スマホサイズでは非表示 */
    justify-content: space-around;
    align-items: center;
  }
  
/*ナビゲーションリンク(ナビゲーションバー個々)*/
  .nav-link {
    background: #0074D9;
    padding: 0.75rem 1rem;
    display: flex;
    white-space: nowrap;
    color: white;
    text-decoration: none;
    max-width: 100%;
    overflow: hidden;
    justify-content:center;
    align-items: center;
    flex: 1;
    /* width: 100%; */
    text-align: center;
  }



  .hamburger {
    font-size: 1.5rem;
    cursor: pointer;
  }
  .hero {
    padding: 2rem;
    text-align: center;
  }

  section{ 
 
   text-align: center;
}

  input[id="inputValue"],
select {
  padding: 0.6rem 1rem;
  font-size: 1rem;
  border: 1px solid #ccc;
  border-radius: 8px;
  width: 100%;
  max-width: 300px;
  box-sizing: border-box;
  margin: 10px auto;
  display: block;
  background-color: #fff;
}

.section.description, section.description {
  max-width: 600px;
  margin: 2.5rem auto 1.5rem auto;
  padding: 1.5rem 2rem;
  background: #eaf6ff;
  border-radius: 10px;
  box-shadow: 0 2px 8px rgba(0,0,0,0.04);
  text-align: center;
}

.section.description p, section.description p {
  margin: 0.7em 0;
  font-size: 1.08em;
}


.section.description .caution, section.description .caution {
  color: #d9534f;
  font-weight: bold;
  margin-top: 1.2em;
}

.form-area {
  max-width: 400px;
  margin: 2rem auto;
  padding: 2rem;
  background: #fff;
  box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08);
  border-radius: 8px;
  display: flex;
  flex-direction: column;
  gap: 1.2rem;
}

button#calcBtn {
  background-color: #0074D9;
  color: white;
  border: none;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  border-radius: 8px;
  cursor: pointer;
  margin: 20px auto;
  display: block;
  transition: background-color 0.2s ease;
}
button#calcBtn:hover {
  background-color: #005fa3;
}

#resultBox {
  margin: 20px auto;
  text-align: center;
  font-size: 1.2rem;
  font-weight: bold;
  color: #0074D9;
}

  footer {
    text-align: center;
    padding: 1rem;
    font-size: 0.9rem;
    background: #eee;
    color: #555;
  }
  

  
  /* スマホサイズ時はハンバーガー表示 */
  .hamburger {
    font-size: 1.5rem;
    cursor: pointer;
    display: block;
  }
  
  /* ハンバーガーメニューとして開いたときの表示 */
  .nav-bar.open {
    display: flex;
    flex-direction: column;
    background: #0074D9;
    position: absolute;
    top: 60px;
    left: 0;
    width: 200px;
    z-index: 1000;
  }
  
  /* PCサイズでは常に表示（ハンバーガーは非表示） */
  @media (min-width: 600px) {
    .nav-bar {
      display: flex !important;
      position: static;
      background: none;
    }
  
    .hamburger {
      display: none;
    }
  
    .nav-link {
        padding: 0.75rem 1rem;
        display: block;
        white-space: nowrap; /* ←これ！ */
        color: white;
        text-decoration: none;
      }}

.explanation-link {
  display: inline-block;
  margin: 2rem auto 1rem auto;
  background: #fff;
  color: #0074D9;
  border: 2px solid #0074D9;
  border-radius: 5px;
  padding: 0.75rem 2rem;
  text-decoration: none;
  font-weight: bold;
  transition: background 0.2s, color 0.2s;
  text-align: center;
}
.explanation-link:hover {
  background: #0074D9;
  color: #fff;
}