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

html,
body {
  height: 100%;
}

body {
  flex-direction: column;
  text-align: center;
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN",
    "Hiragino Sans", Meiryo, sans-serif;
}
main {
  width: auto;

  margin-right: 12px;
  margin-left: 12px;

  max-width: 800px;
  margin: 20px auto; /* 上下20px, 左右自動(中央寄せ) */
}

select {
  background-color: beige;
}

/*おしらせ欄*/
.notice-area {
  text-align: center;
  background-color: lightyellow;
  padding: 10px;
  border-radius: 10px;
  border: 1px solid #000;
  margin: 20px;
  display: grid;
  grid-template-columns: 2fr 3fr;
  gap: 10px;
}
.notice-area h2 {
  font-size: 24px;
  margin-bottom: 10px;
  grid-column: span 2;
}
.notice-area p {
  font-size: 16px;
}
.notice-date {
  text-align: right;
}

.notice-feater {
  text-align: left;
}
/*フィードバック欄*/

.feedback {
  font-size: 16px;
}
/*通常btn表示欄*/
/*btn要素*/
.btn {
  height: 50px;
  width: 200px;

  margin: 20px auto;

  font-size: 18px;

  text-align: center;
  text-decoration: none;
  color: white;
  background-color: #475569;
  position: relative;
  border-radius: 10px;

  display: flex;
  justify-content: center;
  align-items: center;
}

.btn p {
  margin: 0;
  padding: 0;
}
.btn a {
  position: absolute;
  height: 100%;
  width: 100%;
  left: 0;
  top: 0;
  bottom: 0;
  margin: auto;
  border-radius: 10px;
}
/*home btn表示欄*/
.selector {
  width: 100%;
  text-align: center;
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 20px;
  padding: 20px;
}

/*selector-btn要素*/
.selector-btn {
  text-align: center;
  font-size: 24px;
  text-decoration: none;
  color: white;
  background-color: #475569;
  position: relative;
  border-radius: 10px;

  display: flex;
  justify-content: center;
  align-items: center;
  aspect-ratio: 1;
}

.selector-contents {
  display: flex;
  flex-direction: column;
  justify-content: center;
  align-items: center;
}

.selector-btn p {
  margin: 10px;
}
.selector-btn svg {
  margin: 10px;
}
.selector-btn a {
  position: absolute;
  height: 100%;
  width: 100%;
  top: 0;
  left: 0;
  border-radius: 10px;
}

/*フォーム要素*/
.form-container {
  max-width: 600px;
  margin: 0 auto;
  padding: 20px;
}

.form-container h1 {
  font-size: 20px;
  margin-bottom: 20px;
  line-height: 1.5;
}

.form {
  margin: 20px auto;
  font-size: 16px;
  max-width: 400px;

  text-align: center;
}
.form h2 {
  font-size: 24px; /* 程よい大きさに */
  margin-bottom: 20px;
}

.form h4 {
  font-size: 18px;
  margin: 10px 0;
}

/* ラベル（ID, PASSWORD） */
.form label {
  font-size: 16px;
  font-weight: bold;
  display: block; /* 改行させる */
  text-align: left; /* 左揃えの方が見やすい */
  margin-top: 15px;
  margin-bottom: 5px;
}
.form select,
.form input {
  height: 50px;
  font-size: 16px;
  line-height: 1.5;
  padding: 5px, 10px;
  margin-top: 5px;
  margin-bottom: 5px;
  width: 100%;

  box-sizing: border-box;

  border-radius: 6px;
}
.form p {
  font-size: 16px;
  margin: 5px 0 15px 0;
  text-align: right; /* 右寄せのまま */
}
.form button,
.form .button {
  height: 50px;
  font-size: 18px;

  margin-top: 20px;
  width: 100%;
  cursor: pointer;

  background-color: #ffca80;
  color: black;
  border: none;
  border-radius: 10px;

  transition: opacity 0.2s;
}

.form button:hover {
  opacity: 0.8;
}