@charset "utf-8";
/* ======================================================= */
/* リセットCSS -------------------------------------------- */
/* ======================================================= */
*,
::before,
::after {
  box-sizing: border-box;
  border-style: solid;
  border-width: 0;
    }

html {
  line-height: 1.15; /* 1 */
  -webkit-text-size-adjust: 100%; /* 2 */
  -webkit-tap-highlight-color: transparent; /* 3*/
    }

body {
  margin: 0;
    }

main {
  display: block;
    }

p,
table,
blockquote,
address,
pre,
iframe,
form,
figure,
dl {
  margin: 0;
    }

h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: inherit;
  font-weight: inherit;
  margin: 0;
    }

ul,
ol {
  margin: 0;
  padding: 0;
  list-style: none;
    }

dt {
  font-weight: bold;
    }

dd {
  margin-left: 0;
    }

hr {
  box-sizing: content-box; /* 1 */
  height: 0; /* 1 */
  overflow: visible; /* 2 */
  border-top-width: 1px;
  margin: 0;
  clear: both;
  color: inherit;
    }

pre {
  font-family: monospace, monospace; /* 1 */
  font-size: inherit; /* 2 */
    }

address {
  font-style: inherit;
}

a {
  background-color: transparent;
  text-decoration: none;
  color: inherit;
    }

abbr[title] {
  text-decoration: underline dotted; /* 2 */
    }

b,
strong {
  font-weight: bolder;
    }

code,
kbd,
samp {
  font-family: monospace, monospace; /* 1 */
  font-size: inherit; /* 2 */
    }

small {
  font-size: 80%;
    }

sub,
sup {
  font-size: 75%;
  line-height: 0;
  position: relative;
  vertical-align: baseline;
    }

sub {
  bottom: -0.25em;
    }

sup {
  top: -0.5em;
    }

svg,
img,
embed,
object,
iframe {
  vertical-align: bottom;
    }

button,
input,
optgroup,
select,
textarea {
  -webkit-appearance: none; /* 1 */
  appearance: none;
  vertical-align: middle;
  color: inherit;
  font: inherit;
  background: transparent;
  padding: 0;
  margin: 0;
  border-radius: 0;
  text-align: inherit;
  text-transform: inherit; /* 2 */
    }

button,
[type="button"],
[type="reset"],
[type="submit"] {
  cursor: pointer;
    }

button:disabled,
[type="button"]:disabled,
[type="reset"]:disabled,
[type="submit"]:disabled {
  cursor: default;
    }

:-moz-focusring {
  outline: auto;
    }

select:disabled {
  opacity: inherit;
    }

option {
  padding: 0;
    }

fieldset {
  margin: 0;
  padding: 0;
  min-width: 0;
    }

legend {
  padding: 0;
    }

progress {
  vertical-align: baseline;
    }

textarea {
  overflow: auto;
    }

[type="number"]::-webkit-inner-spin-button,
[type="number"]::-webkit-outer-spin-button {
  height: auto;
    }

[type="search"] {
  outline-offset: -2px; /* 1 */
    }

[type="search"]::-webkit-search-decoration {
  -webkit-appearance: none;
    }

::-webkit-file-upload-button {
  -webkit-appearance: button; /* 1 */
  font: inherit; /* 2 */
    }

[type="number"] {
  -moz-appearance: textfield;
    }

label[for] {
  cursor: pointer;
    }

details {
  display: block;
    }

summary {
  display: list-item;
    }

[contenteditable]:focus {
  outline: auto;
    }

table {
  border-color: inherit; /* 1 */
  border-collapse: collapse;
    }

caption {
  text-align: left;
    }

td,
th {
  vertical-align: top;
  padding: 0;
    }

th {
  text-align: left;
  font-weight: bold;
    }

/* リセットCSS --------------------------------------------- */

/* ======================================================= */
/* 全体適用 ----------------------------------------------- */
/* ======================================================= */

/* 全体適用 ------------------------------------  
* {
  outline: 1px solid rgba(255, 0, 0, 0.3);
  }
----------------------------------------------- */ 

*, *::before, *::after {
  box-sizing: border-box;
  }
  
html, body {
  overflow-x: hidden;
  width: 100%;
  }

body {
  font-family: "Comfortaa", sans-serif;
  font-optical-sizing: auto;
  min-height: 100vh;
  background: #221D21;
  background: linear-gradient(to bottom, #221D21, #585257, #3C3F58);
  background-attachment: fixed;
  background-repeat: no-repeat;
  background-size: cover;
  color: #fff;
  text-align: center;
  -webkit-text-size-adjust: 100%;
  opacity: 0;
  transition: opacity 0.5s ease;
  }

body.font-loaded {
  opacity: 1;
  }

body.modal-open {
  overflow: hidden;
  }

img {
  max-width: 100%;
  height: auto;
  display: block;
  }
/* 星空の背景のスタイル */
.stars {
  position: relative;
  width: 100%; /* 星空の横幅 */
  height: 100%; /* 星空の縦幅 */
}

/* 星のスタイル */
.star {
  position: absolute;
  display: block;
  background-color: #fff; /* 星の色 */
  border-radius: 50%;
  box-shadow: 0 0 5px 3px rgba(#fff, 0.2); /* 星の影 */
  opacity: 0;
  animation: twinkle 3s infinite;
  z-index: -9999; /* コンテンツの下に配置 */
  }

/* 星がキラキラ光るアニメーション */
@keyframes twinkle {
  0% { opacity: 0; }
  50% { transform: scale(1.1); opacity: 1; }
  100% { opacity: 0; transform: scale(1); }
  }

/* 流れ星アニメーション */
.shooting-stars-container {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  overflow: hidden;
  pointer-events: none; /* クリック操作を邪魔しない */
  z-index: -999; /* コンテンツの下に配置 */
  }
  
.shooting-star {
  position: absolute;
  width: 120px; /* 流星の長さ */
  height: 2px;   /* 流星の太さ */
  background: linear-gradient(90deg, rgba(255, 234, 128, 1), rgba(255, 234, 128, 0));
  opacity: 0.8;
  transform: rotate(45deg);
  animation: shoot 2s linear forwards;
  }
  
@keyframes shoot {
  0% { transform: translate(0, 0) rotate(45deg); opacity: 1; }
  100% { transform: translate(500px, 500px) rotate(45deg); opacity: 0; }
  }
  
/* header ------------------------------------------------ */

header {
  background: #3C3F58;
  }

/* ナビゲーション */
.nav li {
  font-weight: bold;
  padding: 10px;
  }

/* ミートボールメニュー */
.menu-button {
  position: fixed;
  top: 20px;
  right: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
  width: 60px;
  height: 60px;
  background: transparent;
  border: none;
  cursor: pointer;
  z-index: 1000;
  }

/* ドットの基本スタイル */
.menu-button .dot {
  position: absolute;
  width: 10px;
  height: 10px;
  border-radius: 50%;
  transition: all 0.5s ease;
  box-shadow: 0 0 5px rgba(255, 255, 255, 0.5);
  }

/* ドット */
.menu-button .planet1 {
  background: radial-gradient(circle, #FFD700, #FFA500);
  transform: translateY(-15px);
  }

.menu-button .planet2 {
  background: radial-gradient(circle, #FFFFFF, #AAAAAA);
  transform: translateY(0);
  }

.menu-button .planet3 {
  background: radial-gradient(circle, #87CEEB, #4682B4);
  transform: translateY(15px);
  }

.planet1 { z-index: 2; }
.planet2 { z-index: 3; }  
.planet3 { z-index: 1; } 

/* メニューがアクティブのとき、3つのドットが中央に集合して大きく */
.menu-button.active .dot {
  transform: translateX(0) translateY(0) scale(1.8);
  }

/* メニュー全体（最初は非表示） */
.menu {
  position: fixed;
  top: 0;
  right: -100%;
  width: 70%;
  height: 100vh;
  background-color: #0D0F1E;
  display: flex;
  justify-content: center;
  align-items: center;
  transition: right 0.5s ease, opacity 0.5s ease;
  opacity: 0;
  z-index: 999;
  }

/* メニュー表示時 */
.menu.active {
  right: 0;
  opacity: 1;
  }

/* メニューリスト */
.menu ul.nav {
  list-style: none;
  text-align: center;
  }

.menu ul.nav li {
  margin-bottom: 20px;
  }

.menu ul.nav li a {
  color: #fff;
  text-decoration: none;
  font-size: 1.5em;
  transition: color 0.5s ease;
  }

.menu ul.nav li:first-letter {
  color: #FFD700;
  }

.menu ul.nav li a:hover {
  color: #FFD700;
  }

/* メニューアクティブ時 - 3つのドットが中央に合体して大きく */
.menu-button.active .dot {
  transform: translateY(0) scale(2);
  }

@keyframes galaxySpin {
  0% { transform: rotate(0deg); }
  100% { transform: rotate(360deg); }
  }

/* ドットの移動アニメーション */
.menu-button.active .dot {
  transform: translateX(40px);
  }

/* デスクトップ向けスタイル */
@media (min-width: 1024px) {
  ul.nav {
    display: flex;
    justify-content: center;
    gap: 50px;
    list-style: none;
    padding: 6px 0;
    font-size: 1.5em;
    }

  /* ミートボールメニューボタンを非表示にする */
  .menu-button {
    display: none;
    }
  
  /* メニューを常に表示 */
  .menu {
    position: static;
    display: flex;
    justify-content: flex-end;
    align-items: center;
    width: 100%;
    height: auto;
    opacity: 1;
    transition: none;
    background: transparent;
    z-index: auto;
    }
  
  /* リストを横並びにする */
  .menu ul.nav {
    display: flex;
    gap: 40px;
    list-style: none;
    margin: 0 auto;
    }
  
  /* メニュー項目を調整 */
  .menu ul.nav li {
    margin-bottom: 0;
    }
  
  /* ナビリンクの見た目を整える */
  .menu ul.nav li a {
    font-size: 1em;
    color: #fff;
    }
  }

/* ======================================================= */
/* index ------------------------------------------------- */
/* ======================================================= */

/* メインビジュアル --------------------------------------- */

.animation {
  height: 200px;
  }

h1 {
  font-size: 2em;
  font-weight: bold;
  line-height: 1.5em;
  }

h1::first-letter {
  color: #FFD700;
  }
  
.sub-text {
  font-size: 0.8em;
  color: #ccc;
  margin: 0.5em 0;
  letter-spacing: 0.05em;
  }

.mainvisual-img {
  margin: 40px 0;
  display: flex;
  justify-content: center;
  align-items: center;
  transform-origin: center center;
  transition: transform 0.3s ease;
  transform: scale(0.8);
  }

.mainvisual-astronaut {
  max-width: 70%;
  height: auto;
  margin: 0 20px;
  animation: astronautFloat 5s ease-in-out infinite;
  }

.mainvisual-star1,.mainvisual-star2 {
  max-width: 12%;
  height: auto;
  }

.mainvisual-star1 {
  animation: star1Float 4s ease-in-out infinite;
  }

.mainvisual-star2 {
  animation: star2Float 6s ease-in-out infinite;
  }
  
/* デスクトップ向けスタイル */
@media (min-width: 1024px) {
  .animation {
    height: 150px;
    }
  
  .mainvisual-astronaut {
    max-width: 30%;
    height: auto;
    }
  }

/* アニメーション */
@keyframes astronautFloat {
  0% { transform: translate(0, 0) rotate(0deg); }
  50% { transform: translate(0, -20px) rotate(2deg); }
  100% { transform: translate(0, 0) rotate(0deg); }
  }

@keyframes star1Float {
  0% { transform: translate(0, 0) rotate(-10deg); }
  50% { transform: translate(-10px, -10px) rotate(10deg); }
  100% { transform: translate(0, 0) rotate(-10deg); }
  }

@keyframes star2Float {
  0% { transform: translate(0, 0) rotate(10deg); }
  50% { transform: translate(10px, -15px) rotate(-10deg); }
  100% { transform: translate(0, 0) rotate(10deg);}
  }

/* コンテンツ --------------------------------------------- */

h2 {
  margin: 10px;
  font-size: 2em;
  font-weight: bold;
  }

.border {
  width: 380px;
  border-top: 3px solid #FFD700;
  margin: auto;
  }

/* アニメーション ------------------------------------------ */

/* スクロール */
@import url('https://fonts.googleapis.com/css2?family=Josefin+Sans:wght@300;400&display=swap');

.scroll {
  position: relative;
  height: 100px;
  width: 100%;
  }

.scroll_down {
  position:absolute;
  top: 50%;
  left: 50%;
  transform: translateX(-50%);
  animation: fadeInOut 2s ease-in-out infinite;
  }

.scroll_down p {
  position: absolute;
  left: -24px;
  bottom: 17px;
  color: #fff;
  font-size: 14px;
  font-family: 'Josefin Sans', sans-serif;
  letter-spacing: .2em;
  writing-mode: vertical-rl;
  text-decoration: none;
  text-transform: uppercase;
  }

.scroll_down:before {
  content: "";
  position: absolute;
  bottom: 5px;
  right: -6px;
  width: 2px;
  height: 20px;
  background: #fff;
  transform: skewX(-31deg);
  }

.scroll_down:after {
  content:"";
  position: absolute;
  bottom: 5px;
  right: 0;
  width: 2px;
  height: 85px;
  background:#fff;
  }

@keyframes fadeInOut {
  0%, 100% { opacity: 0.2; }
  50% { opacity: 1; }
  }

 /* フェードイン */
 .fadein.is-animated {
  animation: fadeIn 0.7s cubic-bezier(0.33, 1, 0.68, 1) forwards;
  }
 
@keyframes fadeIn {
  0% { opacity: 0; }
  100% { opacity: 1; }
  }

.fadein {
  opacity: 0;
  transform: translateY(30px);
  transition: opacity 0.7s ease, transform 0.7s ease;
  }
  
.fadein.is-animated {
  opacity: 1;
  transform: translateY(0);
  }

/* 宇宙百科事典 --------------------------------------------- */

#encyclopedia {
  width: 100%;
  max-width: 600px;
  margin: 0 auto;
  box-sizing: border-box;
  overflow: visible;
  }

#encyclopedia .sub-text {
  margin-top: 20px;
  }
  
.encyclopedia-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  max-width: 100%;
  margin: 30px auto;
  padding: 0 30px;
  }
  
.encyclopedia-grid .item {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 0;
  }

.explanation-box {
  width: 100%;
  padding: 10px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #8BA6C1;
  box-shadow: 10px 10px 0 #FFD700;
  box-sizing: border-box;
  overflow-wrap: break-word;
  aspect-ratio: 4 / 3;
  margin: 0 auto;
  }

.planet-box {
  position: relative;
  z-index: 1;
  }

.planet-box::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("images/planet-icon.png");
  background-repeat: no-repeat;
  background-position: 20px 20px;
  background-size: 50px 50px;
  opacity: 0.5;
  z-index: -1;
  }

.rocket-box {
  position: relative;
  z-index: 1;
  }
  
.rocket-box::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("images/rocket-icon.png");
  background-repeat: no-repeat;
  background-position: 20px 20px;
  background-size: 50px 50px;
  opacity: 0.5;
  z-index: -1;
  }

.explanation-box dt {
  font-weight: bold;
  margin-bottom: 20px;
  color: #0D0F1E;
  font-size: 1.1em;
  }

.explanation-box dd {
  color: #3C3F58;
  margin: 0 auto;
  font-size: 0.9em;
  line-height: 1.5rem;
  }

.encyclopedia-grid img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  box-shadow: 10px 10px 0 #8BA6C1;
  display: block;
  }

.astronaut-img {
  max-width: 120px;
  height: auto;
  }

.pickup-wrap {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 20px;
  }

.pickup-balloon {
  background: url('images/pickup-back.png') no-repeat center/contain;
  width: 180px;
  height: 70px;
  display: flex;
  justify-content: center;
  align-items: center;
  color: #3C3F58;
  font-size: 1.2em;
  font-weight: bold;
  text-align: center;
  }

/* デスクトップ向けスタイル */
@media (min-width: 1024px) {
  .astronaut-img {
    max-width: 180px;
    height: auto;
    }

  #encyclopedia {
    max-width: 800px;
    }

  .encyclopedia-grid {
    grid-template-columns: 1fr 1fr;
    grid-template-rows: auto auto;
    width: 100%;
    padding: 0;
    }

    .encyclopedia-grid .item:nth-child(1) { /* 解説1 */
    grid-column: 1;
    grid-row: 1;
    }

  .encyclopedia-grid .item:nth-child(2) { /* 写真1 */
    grid-column: 2;
    grid-row: 1;
    }
  
  .encyclopedia-grid .item:nth-child(3) { /* 解説2 */
    grid-column: 2;
    grid-row: 2;
    }

  .encyclopedia-grid .item:nth-child(4) { /* 写真2 */
    grid-column: 1;
    grid-row: 2;
    }
  }

.encyclopedia-btn {
  padding: 20px;
  margin-bottom: 20px;
  }

 .encyclopedia-btn a {
  display: flex;
  justify-content: center;
  align-items: center;
  position: relative;
  width: 300px;
  height: 60px;
  color: #fff;
  font-size: 18px;
  font-weight: 700;
  text-decoration: none;
  transition: 0.5s;
  margin: 0 auto;
  }
  
.encyclopedia-btn a:hover {
  color: #3C3F58;
  }

.encyclopedia-btn a {
  background-color: #3C3F58;
  border: 1px solid #fff;
  border-radius: 35px;
  }
  
.encyclopedia-btn a:hover {
  background-color: #FFD700  ;
  border: 1px solid #fff;
  }
  
.encyclopedia-btn a::before {
  content: '';
  position: absolute;
  top: calc(50% - 5px);
  right: -35px;
  transform: rotate(30deg);
  width: 12px;
  height: 1px;
  background-color: #fff;
  }
  
.encyclopedia-btn a::after {
  content: '';
  position: absolute;
  top: 50%;
  right: -35px;
  transform: translateY(-50%);
  width: 70px;
  height: 1px;
  background-color: #fff;
  }

/* ギャラリー --------------------------------------------- */

#gallery {
  width: auto;
  }

#gallery h3 {
  font-size: 1.5em;
  padding: 20px 0;
  color: #3C3F58;
  font-weight: bold;
  text-align: center;
  margin: 10px;
  }

#gallery .astronaut-img {
  margin: 0 auto;
  }

.photo {
  width: 100%;
  max-width: 800px;
  margin: 0 auto;
  }

.photo-gallery {
  max-width: 100%;
  padding: 0 30px;
  }

.photo h3 {
  background:no-repeat center/180px url("images/h3-back.png");
  }

.photo-list {
  max-width: auto;
  max-height: auto;
  filter: drop-shadow(10px 10px 5px #0D0F1E);
  }

.photo-slider .photo-item {
  width: 100%;
  height: 100%;
  }

.slider-dots {
  margin: 0;
  position: absolute;
  right: 20px;
  bottom: 25px;
  }

.slider-dots li {
  position: relative;
  width: 20px;
  height: 20px;
  margin-bottom: 10px;
  background: transparent;
  cursor: pointer;
  }
  
.slider-dots li::before {
  content: "★";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  font-size: 20px;
  color: #fff;
  opacity: 0.5;
  transition: color 0.3s ease, transform 0.3s ease;
  }
  
.slider-dots li.slick-active::before,
.slider-dots li:hover::before {
  color: #FFD700;
  opacity: 1;
  will-change: transform, color;
  transform: translate(-50%, -50%) scale(1.1);
  transition: opacity 0.3s ease, background-color 0.3s ease;
  }
  
.slider-dots li button {
  display: none;
  -webkit-appearance: none;
  -moz-appearance: none;
  appearance: none;
  outline: none;
  padding: 0;
  border: none;
  background-color: transparent;
  }

#illustration h3 {    
  background: url("images/h3-back.png") no-repeat center/180px;
  padding: 20px;
  height: 50px;
  line-height: 50px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 20px;
  }

.illust-list {
  width: 100%;
  margin-bottom: 20px;
  filter: drop-shadow(5px 5px 3px #0D0F1E);
  }

.grid-row {
  display: grid;
  justify-content: center;
  margin: 0 auto;
  gap: 20px;
  margin-bottom: 20px;
  }

 .grid-6 {
  grid-template-columns: repeat(3, 1fr);
  max-width: 90%;
  }
  
.grid-3 {
  grid-template-columns: repeat(3, 1fr);
  max-width: 90%;
  }
  
/* デスクトップ向けスタイル */
@media screen and (min-width: 1024px) {
  .photo-gallery {
    padding: 0;
    }

  .illust-list {
    max-width: 80%;
    margin: 0 auto;
    }

  .grid-6 {
    grid-template-columns: repeat(6, 1fr);
    max-width: 90%;
    margin-bottom: 20px;
    }

  .grid-3 {
    max-width: 45%;
    }
  }

.hover-img {
  position: relative;
  overflow: hidden;
  cursor: pointer;
  width: 100%;
  height: auto;
  }
  
.hover-img img {
  display: block;
  width: 100%;
  height: auto;
  transition: opacity 0.5s ease;
  }

.hover-img img:nth-child(2) {
  position: absolute;
  top: 0;
  left: 0;
  opacity: 0;
  }
  
.hover-img:hover img:nth-child(2) {
  opacity: 1;
  }

/* アバウト ---------------------------------------------- */ 

#about {
  width: 100%;
  }

#about img {
  margin: 0 auto 20px;
  }

.padding-box {
 margin: 0 5%;
  }

.planet-rocket-box {
  max-width: 800px;
  padding: 10px;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #8BA6C1;
  box-shadow: 10px 10px 0 #FFD700;
  box-sizing: border-box;
  overflow-wrap: break-word;
  margin: 0 auto;
  position: relative;
  z-index: 1;
  } 

.planet-rocket-box::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-image: url("images/planet-icon.png"), url("images/rocket-icon.png");
  background-position: left top, right bottom;
  background-repeat: no-repeat, no-repeat;
  background-size: 50px 50px;
  opacity: 0.5;
  z-index: -1;
  }

.planet-rocket-box dt {
  font-weight: bold;
  margin: 20px;
  color: #0D0F1E;
  font-size: 1.1em;
  }
  
.planet-rocket-box dd {
  color: #3C3F58;
  max-width: 500px;
  margin-bottom: 30px;
  font-size: 0.9em;
  line-height: 1.5rem;
  }
  
.planet-rocket-box p {
  margin: 10px 0;
  } 
  
/* デスクトップ向けスタイル */
@media screen and (min-width: 1024px) {
  .padding-box {
    margin: 0;
    } 
  }

/* コンタクト --------------------------------------------- */ 

#contact {
  width: 100%;
  margin: 20px 0 40px;   
  }

#contact img {
  margin: 0 auto;
  }

#contact .sub-text {
  margin-bottom: 20px;
  }

#contact-form {
  display: flex;
  flex-direction: column;
  gap: 20px;
  background-color: #fff;
  border-radius: 20px;
  width: 100%;
  max-width: 800px;
  padding: 10px 30px;
  margin: 0 auto;
  }

.form-group {
  display: flex;
  align-items: center;
  flex-direction: column;
  gap: 20px;
  }

label {
  font-size: 1.2em;
  font-weight: bold;
  color: #3C3F58;
  margin-top: 20px;
  }

.required {
  background: #8BA6C1;
  color: #fff;
  padding: 2px 8px;
  border-radius: 5px;
  margin-right: 5px;
  }

input, textarea {
  width: 100%;
  max-width: 500px;
  border: 2px solid #8BA6C1;
  border-radius: 10px;
  font-size: 1em;
  background: #fff;
  color: #3C3F58;
  padding: 10px;
  }

/* デスクトップ向けスタイル */
@media screen and (min-width: 1024px) {
  #contact-form {
    padding: 20px;
    }

  .form-group {
    flex-direction: row;
    align-items: flex-start;
    }

  label {
    width: 250px;
    text-align: left;
    }

  input,
  textarea {
    flex: 1;
    max-width: none;
    text-align: left;
    }

  #name,
  #email {
    padding: 10px;
    margin-bottom: 10px;
    }

  textarea {
    height: 200px;
    }
  }

.submit-btn {
  background: #3C3F58;
  color: #fff;
  padding: 10px 30px;
  border-radius: 15px;
  font-size: 1.2em;
  font-weight: bold;
  display: block;
  margin: 20px auto 0;
  cursor: pointer;
  transition: 0.3s;
  }

.submit-btn:hover {
  background: #8BA6C1;
  }
  
#contact button span + span {
  margin-left: 0.3em;
  }

.modal {
  display: none;
  position: fixed;
  z-index: 9999;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background-color: rgba(0, 0, 0, 0.6);
  }

.modal-content {
  background-color: #fff;
  color: #0D0F1E;
  margin: 15% auto;
  padding: 30px;
  border-radius: 10px;
  width: 80%;
  max-width: 400px;
  text-align: center;
  box-shadow: 0 5px 15px rgba(0,0,0,0.3);
  }

#closeModalBtn {
  margin-top: 20px;
  padding: 10px 20px;
  background: #8BA6C1;
  color: #fff;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  transition: 0.3s;
  }

#closeModalBtn:hover {
  background: #FFD700;
  }

/* ======================================================= */
/* contents ---------------------------------------------- */
/* ======================================================= */

#contents {
  width: 100%;
  max-width: 550px;
  margin: 60px auto 20px;
  box-sizing: border-box;
  overflow: visible;
  }

#contents .sub-text {
  margin-bottom: 20px;
  }

.sub-text2 {
  max-width: 300px;
  font-size: 0.8em;
  margin: 20px auto;
  color: #ccc;
  letter-spacing: 0.05em;
  line-height: 1.5em;
  }

#contents img {
  margin: 0 auto;
  }

.contents-grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 40px;
  max-width: 100%;
  margin: 30px auto;
  padding: 0 30px;
  }
    
.contents-grid .item {
  justify-content: center;
  padding: 0;
  }
  
.contents-grid img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  box-shadow: 10px 10px 0 #8BA6C1;
  display: block;
  }

#contents .explanation-box {
  aspect-ratio: 1 / 1;
  }

/* デスクトップ向けスタイル */
@media (min-width: 1024px) {
  #contents {
    max-width: 800px;
    }

  .sub-text2 {
    max-width: 730px;
    margin: 20px auto;
    }

  .contents-grid {
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    grid-template-rows: repeat(auto-fit, minmax(300px, auto));
    grid-auto-flow: row dense;
    gap: 40px;
    width: 100%;
    padding: 0;
    }

  .contents-grid .item {
    display: block;
    }

  .contents-grid .item:nth-child(4n+1) { /* 解説1 */
    grid-column: 1;
    grid-row: auto;
    }

  .contents-grid .item:nth-child(4n+2) { /* 写真1 */
    grid-column: 2;
    grid-row: auto;
    }

  .contents-grid .item:nth-child(4n+3) { /* 解説2 */
    grid-column: 2;
    grid-row: auto;
    }

  .contents-grid .item:nth-child(4n+4) { /* 写真2 */
    grid-column: 1;
    grid-row: auto;
    }
  }

/* タブメニュー */
.tab-content .sub-text {
  margin-top: 20px;
  font-size: 1em;
  }

.tab-switch {
  display: flex;
  flex-wrap: wrap;
  margin: 0 auto;
  justify-content: center;
  gap: 20px;
  }

#contents label {
  width: 160px;
  margin: 0 10px;
  border-radius: 20px;
  box-shadow: 0 5px 5px rgba(0,0,0,0.3);
  }

.tab-switch > label {
  flex: 1 1 auto;
  order: -1;
  position: relative;
  padding: 1em;
  background-color: #fff;
  color: #999;
  text-align: center;
  cursor: pointer;
  transition:.3s all;
  }

.tab-switch > label:hover{
  background-color: #8BA6C1;
  color: #fff;
  }

.tab-switch label:has(:checked) {
  background-color: #3C3F58;
  color: #fff;
  }

.tab-switch input {
  display: none;
  }

.tab-switch > div {
  display: none;
  width: 100%;
  }

.tab-switch label:has(:checked) + div {
  display: block;
  }

/* ======================================================= */
/* illustration ------------------------------------------ */
/* ======================================================= */

.illustration {
  width: 100%;
  margin: 60px auto 20px;
  }

.illustration img {
  margin: 0 auto;
  }

.illustration .sub-text {
  max-width: 80%;
  margin: 0 auto;
  }

.illustration .planet-rocket-box {
  margin: 30px auto 50px;
  }

.illustration .planet-rocket-box dt {
  letter-spacing: 0.3em;
  }

.character-nav ul {
  display: flex;
  flex-wrap: wrap;
  gap: 1rem;
  align-items: center;
  justify-content: center;
  }

.character-nav li {
  position: relative;
  font-size: 1em;
  transition: color 0.3s;
  cursor: pointer;
  }
  
.character-nav li::after {
  content: '';
  position: absolute;
  bottom: -5px;
  left: 50%;
  width: 0;
  height: 2px;
  background-color: #FFD700;
  transition: width 0.4s ease-in-out;
  transform: translateX(-50%);
  }
  
.character-nav li:hover::after {
  width: 100%;
  }

.character-nav li::first-letter {
  color: #8BA6C1;
  }

.character-grid img {
  max-width: 100%;
  }

.character-grid {
  display: grid;
  grid-template-columns: 1fr;
  max-width: 100%;
  margin: auto;
  }
    
.character-grid .item {
  justify-content: center;
  padding: 0;
  }

.illustration .explanation-box {
  width: 80%;
  padding: 10px;
  height: 80%;
  display: flex;
  align-items: center;
  justify-content: center;
  background-color: #8BA6C1;
  box-shadow: 10px 10px 0 #FFD700;
  box-sizing: border-box;
  overflow-wrap: break-word;
  aspect-ratio: 7 / 9;
  margin: 10px auto 0;
  }

.character-cmt {
  margin-top: 30px;
  }
  
@media (min-width: 1024px) {
  .illustration {
    max-width: 100%;
    }

  .character-grid {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: center;
    }

  .character-grid .item {
    display: block;
    }

  .image-box {
    margin-right: -300px;
    z-index: 1;
    position: relative;
    }

  .image-box2 {
    margin-left: -300px;
    z-index: 1;
    position: relative;
    }

  .image-box3 {
    margin-right: -200px;
    z-index: 1;
    position: relative;
    }
  
  .illustration .explanation-box {
    width: 50%;
    height: 50%;
    margin-top: 5px;
    }
  
  .character-grid:nth-of-type(even) {
    flex-direction: row-reverse;
    }

  .character-grid .item {
    flex: 1 1 50%;
    box-sizing: border-box;
    }
  }

/* ======================================================= */
/* footer ------------------------------------------------ */
/* ======================================================= */

footer {
  height: 100px;
  background: #0D0F1E;
  padding: 10px 0;
  }

.copyright {
  margin-top: 20px;
  font-size: small;
  }

/* ページトップへ戻る --------------------------------------- */

.page-top {
  padding: 0;
  margin: 0;
  display: none;
  position: fixed;
  bottom: 10px;
  right: 10px;
  width: 100px;
  height: 100px;
  border-radius: 50%;
  cursor: pointer;
  z-index: 100;
  filter: drop-shadow(3px 3px 3px #0D0F1E);
  display: flex;
  justify-content: center;
  align-items: center;
  }
  
.page-top img {
  width: 80%;
  height: auto;
  display: block;
  }

.page-top:hover {
  opacity: 1;
  }