/* ==================================================
   共通設定・共通コンポーネント
================================================== */

:root {
  --navy: #102e59;
  --navy-dark: #081c38;
  --red: #a33a32;
  --ink: #28251f;
  --paper: #f4eddd;
  --paper-light: #fbf7ed;
  --line: #c9baa0;
  --shadow: 0 12px 34px rgba(40, 31, 18, .13);
  /*--serif: "Noto Serif JP", "Yu Mincho", "Hiragino Mincho ProN", serif;*/
  
}


*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0 auto;
  color: var(--ink);
  background: #ded8ca;
  /*font-family: var(--serif);*/
  line-height: 1.9;
  font-family: "Noto Sans JP", system-ui, -apple-system, BlinkMacSystemFont, "Yu Gothic", sans-serif;
  max-width: 2280px;
  width: 100%;
}

img {
  display: block;
  max-width: 100%;
  height: auto;
}

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

button {
  font: inherit;
}

h1,
h2,
.hero__lead {
  font-family: "Noto Serif JP", serif;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

.container {
  width: min(1180px, calc(100% - 64px));
  margin-inline: auto;
}

.section-paper {
  position: relative;
  overflow: hidden;
  background-color: var(--paper-light);
  background-image: linear-gradient(rgba(255, 255, 255, .25), rgba(255, 255, 255, .25)), url("../images/paper-texture.png");
  background-repeat: repeat;
}

/*.section-paper+.section-paper {
  border-top: 1px solid rgba(122, 99, 64, .28);
}*/

.section-title {
  margin: 0 0 34px;
  color: var(--navy);
  text-align: center;
  font-size: clamp(1.4rem, 2.5vw, 2rem);
  letter-spacing: .08em;
}

/* 共通設定・共通コンポーネント：タブレット */

@media (max-width: 900px) {
  .container {
    width: min(100% - 40px, 720px);
  }
}

/* 共通設定・共通コンポーネント：スマートフォン */

@media (max-width: 600px) {
  body {
    font-size: 14px;
  }
  
  .container {
    width: calc(100% - 32px);
  }
}


/* ==================================================
   ヘッダー・グローバルナビ
================================================== */

.header {
  position: sticky;
  z-index: 20;
  top: 0;
  background: rgba(251, 247, 237, .94);
  border-bottom: 1px solid var(--line);
  backdrop-filter: blur(8px);
}

.header__inner {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  width: min(1180px, calc(100% - 64px));
  min-height: 72px;
  margin-inline: auto;
}

.header__title {
  display: none;
  margin-right: auto;
  color: var(--navy);
  font-weight: 700;
}

.global-nav {
  display: flex;
  align-items: center;
  gap: 34px;
  font-size: .82rem;
  font-weight: 600;
}

.global-nav a {
  position: relative;
  padding-block: 8px;
}

.global-nav a::after {
  position: absolute;
  right: 0;
  bottom: 2px;
  left: 0;
  height: 1px;
  background: var(--navy);
  content: "";
  transform: scaleX(0);
  transition: transform .25s;
}

.global-nav a:hover::after {
  transform: scaleX(1);
}

.menu-button {
  display: none;
}

/* ヘッダー・グローバルナビ：タブレット */

@media (max-width: 900px) {
  .header__inner {
    width: calc(100% - 40px);
    min-height: 62px;
  }
  
  .header__title {
    display: block;
  }
  
  .menu-button {
    display: flex;
    position: relative;
    z-index: 2;
    flex-direction: column;
    justify-content: center;
    gap: 5px;
    width: 42px;
    height: 42px;
    padding: 8px;
    color: var(--navy);
    background: transparent;
    border: 0;
    cursor: pointer;
  }
  
  .menu-button>span:not(.visually-hidden) {
    display: block;
    width: 100%;
    height: 2px;
    background: currentColor;
    transition: .25s;
  }
  
  .menu-button[aria-expanded="true"]>span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
  }
  
  .menu-button[aria-expanded="true"]>span:nth-child(2) {
    opacity: 0;
  }
  
  .menu-button[aria-expanded="true"]>span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
  }
  
  .global-nav {
    display: none;
    position: absolute;
    top: 62px;
    right: 0;
    left: 0;
    flex-direction: column;
    gap: 0;
    padding: 12px 20px 22px;
    background: rgba(251, 247, 237, .98);
    border-bottom: 1px solid var(--line);
  }
  
  .global-nav.is-open {
    display: flex;
  }
  
  .global-nav a {
    width: 100%;
    padding: 12px;
    border-bottom: 1px dotted var(--line);
    text-align: center;
  }
}

/* ヘッダー・グローバルナビ：スマートフォン */

@media (max-width: 600px) {
  .header__inner {
    width: calc(100% - 32px);
  }
  
  .header__title {
    max-width: 240px;
    font-size: .9rem;
  }
}


/* ==================================================
   Hero
================================================== */

.hero {
  padding: 54px 0 66px;
  overflow: visible;
  z-index: 4;
}

.hero__inner {
  position: relative;
  z-index: 2;
  display: flex;
  /*align-items: center;*/
  gap: 52px;
  
}

.hero__copy {
  flex: 1 1 44%;
  padding-left: 42px;
}

.eyebrow {
  margin: 0 0 12px;
  font-weight: 600;
  letter-spacing: .08em;
}

.hero h1 {
  margin: 0;
  font-size: clamp(3rem, 5.4vw, 4.2rem);
  line-height: 1.5;
  letter-spacing: .06em;
}

.hero h1 em {
  color: var(--navy);
  font-style: normal;
}

.hero__lead {
  margin: 14px 0;
  font-size: clamp(1.35rem, 2.3vw, 2rem);
  font-weight: 600;
  letter-spacing: .08em;
}

.hero__text {
  max-width: 520px;
  margin: 0 0 26px;
  font-size: .92rem;
}

.hero__book {
  flex: 0 1 360px;
  padding: 0;
  
}

.hero__book img {
  width: 100%;
  background: #eee4cf;
  object-fit: cover;
  box-shadow: 6px 6px 10px 0px rgba(0, 0, 0, 0.4);
}

.hero__points {
  display: flex;
  flex: 0 1 270px;
  flex-direction: column;
  gap: 32px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.hero__points li {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

/* アイコン部分 */
.point-icon {
  display: flex;
  flex: 0 0 70px;
  align-items: center;
  justify-content: center;
  width: 70px;
  height: 70px;
}

.point-icon img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
}

/* 文章部分 */
.point-text {
  display: flex;
  flex: 1;
  flex-direction: column;
}

.point-text small {
  display: block;
  color: var(--ink);
  font-size: 0.72rem;
  line-height: 1.75;
}

.hero__points strong {
  color: var(--navy);
  line-height: 1.55;
}

.hero__points small {
  display: block;
  line-height: 1.65;
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 220px;
  min-height: 54px;
  padding: 12px 28px;
  border: 1px solid var(--navy);
  border-radius: 3px;
  font-weight: 700;
  transition: .25s;
}

.button--primary {
  color: #fff;
  background: var(--navy);
  box-shadow: 0 5px 14px rgba(16, 46, 89, .22);
}

.button--primary:hover {
  background: var(--navy-dark);
  transform: translateY(-2px);
}


.hero__decoration,
.concept__decoration,
.book-summary__decoration,
.recommend__decoration,
.contents__decoration,
.learning__decoration,
.author__decoration,
.purchase__decoration {
  position: absolute;
  z-index: 1;
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  pointer-events: none;
}

.hero__decoration--left {
  top: 0;
  bottom: 0;
  left: 0;
  width: 100%;
  height: 960px;
  background-image: url("../images/bg-hero-tools.png");
  background-position: left center;
  opacity: .4;
}

.hero__decoration--right {
  right: 0;
  bottom: -14px;
  width: 980px;
  height: 520px;
  background-image: url("../images/bg-hero-ship.png");
  background-position: right bottom;
  opacity: .4;
}
/*@media (max-width: 1480px) {
  .hero__decoration--left,
  .hero__decoration--right {
    opacity: .4;
  }
}*/

.hero__decoration--left-jar {
  bottom: -16%;
  left: 26%;
  width: 260px;
  height: 340px;
  background-image: url("../images/bg-hero-jar.png");
  background-position: left bottom;
  opacity: .3;
  z-index: 0;
}

.hero__decoration--center {
  top: 40%;
  left: 40%;
  width: min(90%, 1280px);
  height: 500px;
  background-image: url("../images/bg-hero-color.png");
  background-repeat: no-repeat;
  background-position: center;
  background-size: contain;
  opacity: .5;
  z-index: 0;
  transform: translate(-50%, -50%);
}

.hero__decoration--right-wallart {
  right: 5%;
  top: 0;
  width: 460px;
  height: 320px;
  background-image: url("../images/bg-hero-wallart.png");
  background-position: right top;
  opacity: .3;
}

/* Hero：タブレット */

@media (max-width: 900px) {
  .hero__inner {
    flex-wrap: wrap;
  }
  
  .hero__copy {
    flex: 1 1 55%;
    padding-left: 0;
  }
  
  .hero__book {
    flex-basis: 34%;
  }
  
  .hero__points {
    flex-basis: 100%;
    flex-direction: row;
  }
  
  .hero__points li {
    flex: 1;
  }
}

/* Hero：スマートフォン */

@media (max-width: 600px) {
  .hero {
    padding: 40px 0 50px;
  }
  
  .hero__inner {
    flex-direction: column;
    gap: 32px;
  }
  
  .hero__copy {
    width: 100%;
    text-align: center;
  }
  
  .hero h1 {
    font-size: clamp(2.7rem, 14vw, 4rem);
  }
  
  .hero__text {
    text-align: left;
  }
  
  .hero__book {
    width: min(74%, 310px);
  }
  
  .hero__points {
    flex-direction: column;
    width: 100%;
  }
  
  .hero__points small {
    flex-basis: calc(100% - 59px);
  }
  
  .hero__decoration--left {
    width: 55%;
    opacity: .18;
  }
  
  .hero__decoration--ship {
    width: 110px;
    opacity: .55;
  }
}


/* ==================================================
   コンセプト
================================================== */

.concept {
  padding: 66px 0;
  overflow: visible;
}

.concept__inner {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 58px;
}

.concept__copy {
  flex: 1 1 40%;
}

.concept__copy h2,
.book-summary h2,
.learning h2,
.author h2,
.purchase h2 {
  margin: 0 0 22px;
  color: var(--navy);
  font-size: clamp(1.45rem, 2.5vw, 2.15rem);
  letter-spacing: .06em;
}

.concept__copy p {
  margin: 0 0 13px;
}

.concept__cards {
  display: flex;
  flex: 1 1 60%;
  gap: 20px;
}

.image-card {
  flex: 1;
  padding: 10px 10px 18px;
  text-align: center;
  background: rgba(255, 255, 255, .3);
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: 0 8px 20px rgba(54, 39, 20, .07);
}

.image-card img {
  width: 100%;
  aspect-ratio: 4 / 5;
  object-fit: cover;
}

.image-card h3 {
  margin: 12px 0 0;
  color: var(--navy);
  font-size: 1rem;
}

.image-card p {
  margin: 2px 0 0;
  font-size: .78rem;
  line-height: 1.6;
}

.concept__decoration-color {
  top: 30%;
  bottom: 0;
  right: 0;
  width: 100%;
  height: 580px;
  background-image: url("../images/bg-concept-color.png");
  background-position: left center;
  opacity: .5;
}

.concept__decoration-temple {
  top: 30%;
  bottom: 0;
  right: 0;
  width: 100%;
  height: 380px;
  background-image: url("../images/bg-concept-temple.png");
  background-position: right top;
  opacity: .4;
}

/* コンセプト：タブレット */

@media (max-width: 900px) {
  .concept__inner {
    flex-direction: column;
    align-items: stretch;
  }
}

/* コンセプト：スマートフォン */

@media (max-width: 600px) {
  .concept {
    padding-block: 48px;
  }
  
  .concept__cards {
    flex-direction: column;
  }
  
  .image-card {
    width: 100%;
  }
  
  .image-card img {
    aspect-ratio: 16 / 9;
  }
}


/* ==================================================
   書籍概要
================================================== */

.book-summary {
  position: relative;
  padding: 58px 0;
  overflow: visible;
}

.book-summary__inner {
  position: relative;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: clamp(24px, 3vw, 46px);
}

.book-summary__data {
  flex: 1 1 36%;
  min-width: 0;
}

.book-summary__cover {
  flex: 0 1 220px;
  width: 220px;
  margin: 0;
}

.book-summary__cover img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: contain;
  box-shadow: 6px 8px 16px rgba(38, 29, 18, .3);
}

.book-summary__intro {
  flex: 1 1 38%;
  min-width: 0;
  margin: 0;
  padding-left: clamp(24px, 3vw, 42px);
  border-left: 1px solid var(--line);
}

.book-summary dl {
  margin: 0;
}

.book-summary dl div,
.book-info dl div {
  display: flex;
  align-items: flex-start;
  padding: 7px 0;
  border-bottom: 1px dotted var(--line);
}

.book-summary dt {
  display: flex;
  flex: 0 0 105px;
  align-items: center;
  justify-content: center;
  min-height: 32px;
  padding: 2px 10px;
  color: #fff;
  background: var(--navy);
  font-size: .75rem;
  line-height: 1.4;
  text-align: center;
}

.book-summary dd {
  min-width: 0;
  margin: 0;
  padding-left: 20px;
}

.book-summary__decoration {
  top: 0;
  right: 0;
  bottom: 0;
  width: 330px;
  height: 720px;
  background-image: url("../images/bg-paint.png");
  background-position: right bottom;
  opacity: .6;
}

/* 書籍概要：タブレット */

@media (max-width: 900px) {
  .book-summary__inner {
    flex-direction: column;
    align-items: stretch;
    gap: 32px;
  }
  
  .book-summary__cover {
    flex: none;
    width: min(62%, 260px);
    margin-inline: auto;
  }
  
  .book-summary__intro {
    margin: 0;
    padding: 0;
    border: 0;
  }
}

/* 書籍概要：スマートフォン */

@media (max-width: 600px) {
  .book-summary {
    padding-block: 48px;
  }
  
  .book-summary dl div {
    flex-direction: column;
    gap: 6px;
  }
  
  .book-summary dt {
    width: 84px;
  }
  
  .book-summary dd {
    padding: 0;
  }
}


/* ==================================================
   おすすめ
================================================== */

.recommend {
  padding: 60px 0 72px;
  position: relative;
  overflow: visible;
}

.recommend__decoration-chip {
  top: 0;
  left: 0;
  width: 100%;
  height: 640px;
  background-image: url("../images/bg-recommended-chip.png");
  background-position: left top;
  opacity: .6;
}

.recommend__decoration-ship {
  top: -30%;
  right: 26%;
  width: 100%;
  height: 420px;
  background-image: url("../images/bg-recommended-ship.png");
  background-position: right bottom;
  opacity: .3;
}

.recommend__inner {
  position: relative;
  z-index: 2;
}

.recommend__list {
  display: flex;
  gap: 18px;
}

.recommend article {
  flex: 1;
  padding: 28px 18px 24px;
  text-align: center;
  border: 1px solid var(--line);
  border-radius: 7px;
  background: rgba(255, 255, 255, .25);
}

.recommend__icon {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 90px;
  height: 90px;
  margin: 0 auto;
}

.recommend__icon img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;

  /* 白背景を紙のテクスチャになじませる */
  mix-blend-mode: multiply;
}

.recommend h3 {
  margin: 16px 0 8px;
  color: var(--navy);
  font-size: 1rem;
  line-height: 1.65;
}

.recommend p {
  margin: 0;
  font-size: .75rem;
  line-height: 1.75;
}

/* おすすめ：スマートフォン */

@media (max-width: 600px) {
  .recommend {
    padding-block: 48px;
  }
  
  .recommend__list {
    flex-direction: column;
    gap: 12px;
  }
  
  .recommend article {
    padding: 22px 18px;
  }
}


/* ==================================================
   この本で学べること
================================================== */

.learning {
  padding: 66px 0;
}

.learning__inner {
  display: flex;
  align-items: center;
  gap: 46px;
  position: relative;
  z-index: 3;
}

.learning__decoration-chemical {
  top: 5%;
  left: 3%;
  width: 100%;
  height: 420px;
  background-image: url("../images/bg-learning-chemical.png");
  background-position: left top;
  opacity: .3;
}

.learning__copy {
  flex: 0 1 47%;
}

.learning ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

.learning li {
  position: relative;
  padding: 3px 0 3px 28px;
  font-size: .9rem;
}

.learning li::before {
  position: absolute;
  top: 10px;
  left: 0;
  width: 14px;
  height: 14px;
  color: white;
  background: var(--navy);
  border-radius: 3px;
  content: "✓";
  font-size: 9px;
  line-height: 14px;
  text-align: center;
}

.learning img {
  flex: 1 1 53%;
  width: 53%;
  box-shadow: var(--shadow);
}

/* この本で学べること：タブレット */

@media (max-width: 900px) {
  .learning__inner {
    flex-direction: column;
    align-items: stretch;
  }
  
  .learning img {
    width: 100%;
  }
}

/* この本で学べること：スマートフォン */

@media (max-width: 600px) {
  .learning {
    padding-block: 48px;
  }
}


/* ==================================================
   目次・アコーディオン
================================================== */

.contents {
  position: relative;
  padding: 64px 0 80px;
}

.contents__inner {
  position: relative;
  z-index: 2;
  max-width: 960px;
}

.contents__decoration--ship {
  top: 0;
  left: 2%;
  width: 480px;
  height: 480px;
  background-image: url("../images/bg-contents-ship.png");
  background-position: left top;
  opacity: .4;
}

.contents__decoration--globe {
  top: 280px;
  right: 0;
  bottom: auto;
  width: 320px;
  height: 560px;
  background-image: url("../images/bg-contents-globe.png");
  background-position: right bottom;
  opacity: .6;
}

.contents__decoration--feather {
  right: 1%;
  bottom: 3%;
  width: 160px;
  height: 250px;
  background-image: url("../images/bg-contents-feather.png");
}

.contents__list {
  display: flex;
  flex-direction: column;
  gap: 8px;
}

details {
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, .3);
}

/* 目次内の章別リスト */
.chapter-list {
  margin: 0;
  padding: 0;
  list-style: none;
  counter-reset: subsection;
}

/* 章番号 */
.chapter-list--1 {
  --chapter-number: "1-";
}

.chapter-list--2 {
  --chapter-number: "2-";
}

.chapter-list--3 {
  --chapter-number: "3-";
}

.chapter-list--4 {
  --chapter-number: "4-";
}

.chapter-list--5 {
  --chapter-number: "5-";
}

.chapter-list--6 {
  --chapter-number: "6-";
}

.chapter-list--7 {
  --chapter-number: "7-";
}

.chapter-list--8 {
  --chapter-number: "8-";
}

/* 各項目 */
.chapter-list li {
  position: relative;
  padding-left: 3.5em;
  counter-increment: subsection;
}

/* 「1-1」などの番号 */
.chapter-list li::before {
  position: absolute;
  top: 0;
  left: 0;
  color: var(--ink);
  content: var(--chapter-number) counter(subsection);
}

summary {
  position: relative;
  padding: 15px 54px 15px 22px;
  color: var(--navy);
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary span {
  display: inline-block;
  min-width: 90px;
  margin-right: 16px;
  color: #fff;
  background: var(--navy);
  border-radius: 999px;
  font-size: .76rem;
  text-align: center;
}

summary::after {
  position: absolute;
  top: 50%;
  right: 22px;
  width: 12px;
  height: 12px;
  border-right: 2px solid var(--navy);
  border-bottom: 2px solid var(--navy);
  content: "";
  transform: translateY(-70%) rotate(45deg);
  transition: transform .25s;
}

details[open] summary::after {
  transform: translateY(-30%) rotate(225deg);
}
.details-body {
  position: relative;
  isolation: isolate;
  display: block;
  padding: 22px 70px 28px 130px;
  border-top: 1px dotted var(--line);
}

.details-body p,
.details-body ol {
  margin: 0;
}

.details-body ol {
  padding-left: 1.4em;
}

/* ========================================
   目次・アコーディオン内部
======================================== */

.details-body {
  position: relative;
  isolation: isolate;
  display: block;
  min-height: var(--chapter-min-height, 140px);
  padding: 22px 70px 28px 130px;
  border-top: 1px dotted var(--line);
  box-sizing: border-box;
}

/* 章ごとの背景イラスト */
.details-body::after {
  position: absolute;
  z-index: 0;

  /* 本文の高さに合わせて画像領域を伸縮 */
  top: 10px;
  right: var(--chapter-image-right, 24px);
  bottom: 10px;

  /* heightは指定しない */
  width: var(--chapter-image-width, 280px);

  background-image: var(--chapter-image);
  background-repeat: no-repeat;
  background-position:
    var(--chapter-image-position, right bottom);
  background-size: contain;

  content: "";
  opacity: var(--chapter-image-opacity, .42);
  pointer-events: none;
  mix-blend-mode: multiply;
}

/* 目次の文章をイラストより前面に配置 */
.chapter-list {
  position: relative;
  z-index: 1;
  margin: 0;
  padding-left: 1.4em;
}

/* 目次番号 */
.chapter-list {
  list-style: none;
  counter-reset: chapter-item;
}

.chapter-list li {
  position: relative;
  padding-left: 72px;
  line-height: 1.8;
  counter-increment: chapter-item;
}

.chapter-list li::before {
  position: absolute;
  top: 0;
  left: 0;
  width: 58px;
  content:
    var(--chapter-number)
    "-"
    counter(chapter-item);
  white-space: nowrap;
}

/* ========================================
   第1章
======================================== */

.details-body--chapter01 {
  --chapter-image:
    url("../images/contents-chapter01.png");
  --chapter-number: "1";
  --chapter-min-height: 0px;
  --chapter-image-width: 300px;
  --chapter-image-right: 24px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .4;
}

/* ========================================
   第2章
======================================== */

.details-body--chapter02 {
  --chapter-image:
    url("../images/contents-chapter02.png");
  --chapter-number: "2";
  --chapter-min-height: 0px;
  --chapter-image-width: 280px;
  --chapter-image-right: 24px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .4;
}

/* ========================================
   第3章
======================================== */

.details-body--chapter03 {
  --chapter-image:
    url("../images/contents-chapter03.png");
  --chapter-number: "3";
  --chapter-min-height: 0px;
  --chapter-image-width: 280px;
  --chapter-image-right: 24px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .4;
}

/* ========================================
   第4章
======================================== */

.details-body--chapter04 {
  --chapter-image:
    url("../images/contents-chapter04.png");
  --chapter-number: "4";
  --chapter-min-height: 0px;
  --chapter-image-width: 270px;
  --chapter-image-right: 24px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .38;
}

/* ========================================
   第5章
======================================== */

.details-body--chapter05 {
  --chapter-image:
    url("../images/contents-chapter05.png");
  --chapter-number: "5";
  --chapter-min-height: 170px;
  --chapter-image-width: 270px;
  --chapter-image-right: 28px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .4;
}

/* ========================================
   第6章
======================================== */

.details-body--chapter06 {
  --chapter-image:
    url("../images/contents-chapter06.png");
  --chapter-number: "6";
  --chapter-min-height: 170px;
  --chapter-image-width: 250px;
  --chapter-image-right: 30px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .35;
}

/* ========================================
   第7章
======================================== */

.details-body--chapter07 {
  --chapter-image:
    url("../images/contents-chapter07.png");
  --chapter-number: "7";
  --chapter-min-height: 170px;
  --chapter-image-width: 260px;
  --chapter-image-right: 28px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .38;
}

/* ========================================
   第8章
======================================== */

.details-body--chapter08 {
  --chapter-image:
    url("../images/contents-chapter08.png");
  --chapter-number: "8";
  --chapter-min-height: 170px;
  --chapter-image-width: 270px;
  --chapter-image-right: 28px;
  --chapter-image-position: right bottom;
  --chapter-image-opacity: .4;
}

/* ========================================
   タブレット・スマホ
======================================== */

/* ========================================
   アコーディオンを使用しない目次項目
======================================== */

.contents__static-item {
  display: flex;
  align-items: center;
  min-height: 56px;
  padding: 15px 54px 15px 22px;
  color: var(--navy);
  background: rgba(255, 255, 255, 0.3);
  border: 1px solid var(--line);
  font-weight: 600;
}

/* 「はじめに」「序章」のラベル */
.contents__static-item > span {
  display: inline-block;
  flex: 0 0 90px;
  min-width: 90px;
  margin-right: 16px;
  color: #fff;
  background: var(--navy);
  border-radius: 999px;
  font-size: 0.76rem;
  line-height: 1.9;
  text-align: center;
}

/* タイトル */
.contents__static-item > p {
  margin: 0;
}

/* アコーディオンの開閉部分 */
:root {
  interpolate-size: allow-keywords;
}

details {
  overflow: hidden;
  border: 1px solid var(--line);
  background: rgba(255, 255, 255, 0.3);
}

details::details-content {
  display: block;
  height: 0;
  overflow: hidden;
  opacity: 0;

  transition:
    height 0.45s cubic-bezier(0.25, 1, 0.5, 1),
    opacity 0.3s ease,
    content-visibility 0.45s;

  transition-behavior: allow-discrete;
}

details[open]::details-content {
  height: auto;
  opacity: 1;
}

summary {
  position: relative;
  padding: 15px 54px 15px 22px;
  color: var(--navy);
  cursor: pointer;
  font-weight: 600;
  list-style: none;
}

summary::-webkit-details-marker {
  display: none;
}

summary::after {
  position: absolute;
  top: 50%;
  right: 22px;
  width: 12px;
  height: 12px;
  border-right: 2px solid var(--navy);
  border-bottom: 2px solid var(--navy);
  content: "";
  transform: translateY(-70%) rotate(45deg);

  transition:
    transform 0.4s cubic-bezier(0.25, 1, 0.5, 1);
}

details[open] summary::after {
  transform: translateY(-30%) rotate(225deg);
}

.details-body {
  padding: 12px 28px 20px 130px;
  border-top: 1px dotted var(--line);
  transform: translateY(-8px);

  transition:
    transform 0.4s cubic-bezier(0.25, 1, 0.5, 1);
}

details[open] .details-body {
  transform: translateY(0);
}

/* 目次・アコーディオン：タブレット・スマートフォン */

@media (max-width: 700px) {
  .details-body {
      min-height: var(--chapter-min-height-sp, 140px);
      padding: 20px 24px 24px;
    }
  
    .details-body::after {
      top: auto;
      right: 8px;
      bottom: 8px;
      width: var(--chapter-image-width-sp, 150px);
      height: 120px;
      opacity: var(--chapter-image-opacity-sp, .14);
    }
  
    .chapter-list {
      padding-left: 0;
    }
  
    .chapter-list li {
      padding-left: 54px;
      font-size: .88rem;
      line-height: 1.8;
    }
  
    .chapter-list li::before {
      width: 46px;
    }
  
    .details-body--chapter01,
    .details-body--chapter02,
    .details-body--chapter03,
    .details-body--chapter04,
    .details-body--chapter05,
    .details-body--chapter06,
    .details-body--chapter07,
    .details-body--chapter08 {
      --chapter-min-height-sp: 140px;
      --chapter-image-width-sp: 150px;
      --chapter-image-opacity-sp: .12;
    }
}

/* 目次・アコーディオン：スマートフォン */

@media (max-width: 600px) {
  .contents {
    padding-block: 48px;
  }
  
  .contents__static-item {
      flex-direction: column;
      align-items: flex-start;
      gap: 6px;
      padding: 15px 46px 15px 22px;
      line-height: 1.55;
    }
  
    .contents__static-item > span {
      flex-basis: auto;
      min-width: 76px;
      width: max-content;
      margin-right: 0;
    }
  
  summary {
    display: flex;
    flex-direction: column;
    gap: 6px;
    padding-right: 46px;
    line-height: 1.55;
  }
  
  summary span {
    min-width: 76px;
    width: max-content;
    margin: 0;
  }
  
  .details-body {
    padding: 14px 20px 20px;
  }
  
  .contents__decoration {
    opacity: .18;
  }
  
  /* 元ファイル末尾の上書き結果を維持 */
  summary {
    padding: 15px 54px 15px 22px;
  }
  
  .details-body {
    padding: 12px 28px 20px 130px;
  }
}


/* ==================================================
   著者・書籍情報
================================================== */

.author {
  padding: 70px 0;
  z-index: 6;
  overflow: visible;
}

.author__decoration--book {
  bottom: -16px;
  right: 0;
  width: 240px;
  height: 260px;
  background-image: url("../images/bg-author-book.png");
  background-position: rgiht bottom;
  opacity: .4;

}.author__decoration--brush {
  top: -16%;
  left: 0;
  width: 280px;
  height: 360px;
  background-image: url("../images/bg-author-brush.png");
  background-position: left top;
  opacity: .4;
}

.author__inner {
  display: flex;
  align-items: stretch;
  gap: 20px;
  position: relative;
  z-index: 2;
}

.author article {
  flex: 1;
  padding: 32px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(255, 255, 255, .25);
}

.author h2 {
  font-size: 1.3rem;
}

.author p {
  margin: 0 0 12px;
  font-size: .82rem;
}

.author .author-message {
  position: relative;
  overflow: hidden;

  /* イラストを置くスペースを確保 
  padding-bottom: 190px;*/
}

.author .author-message::after {
  position: absolute;
  z-index: 0;
  right: 8px;
  bottom: 8px;
  width: 180px;
  aspect-ratio: 1 / 1;

  background-image:
    url("../images/author-image_01.png");
  background-repeat: no-repeat;
  background-position: right bottom;
  background-size: contain;

  content: "";
  opacity: 1;
  pointer-events: none;

  /* 白背景を紙テクスチャになじませる */
  mix-blend-mode: multiply;
}

.author-message h2,
.author-message p {
  position: relative;
  z-index: 1;
}

.author .author-profile {
  position: relative;
  overflow: hidden;
}
.author .author-profile::after {
  position: absolute;
  z-index: 0;
  right: 8px;
  bottom: 8px;
  width: 180px;
  aspect-ratio: 1 / 1;

  background-image:
    url("../images/author-image_02b.png");
  background-repeat: no-repeat;
  background-position: right bottom;
  background-size: contain;

  content: "";
  opacity: 1;
  pointer-events: none;

  /* 白背景を紙テクスチャになじませる */
  mix-blend-mode: multiply;
}

.author-profile__body {
  display: flex;
  gap: 18px;
}

/*.author-profile img {
  width: 90px;
  height: 110px;
  object-fit: cover;
  filter: sepia(.18);
}*/

.author-profile h3 {
  margin: 0 0 10px;
  color: var(--navy);
  font-size: 1rem;
}

.author-profile h3 small {
  font-weight: 400;
}

.book-info__body {
  display: flex;
  gap: 18px;
}

.book-info {
  position: relative;
  overflow: hidden;
}

.book-info::after {
  position: absolute;
  z-index: 0;
  right: 8px;
  bottom: 8px;
  width: 180px;
  aspect-ratio: 1 / 1;

  background-image:
    url("../images/book-cover.jpg");
  background-repeat: no-repeat;
  background-position: right bottom;
  background-size: contain;

  content: "";
  opacity: 1;
  pointer-events: none;

  /* 白背景を紙テクスチャになじませる */
  mix-blend-mode: multiply;
}


.book-info dl {
  flex: 1;
  font-size: .74rem;
}

.book-info dt {
  flex: 0 0 58px;
  font-weight: 700;
}

.book-info dd {
  margin: 0;
}

.book-info img {
  width: 90px;
  height: 124px;
  object-fit: cover;
}

/* 著者・書籍情報：タブレット */

@media (max-width: 900px) {
  .author__inner {
    flex-wrap: wrap;
  }
  
  .author article {
    flex-basis: calc(50% - 10px);
  }
  
  .author .book-info {
    flex-basis: 100%;
  }
}

/* 著者・書籍情報：スマートフォン */

@media (max-width: 600px) {
  .author {
    padding-block: 48px;
  }
  
  .author__inner {
    flex-direction: column;
  }
  
  .author article {
    padding: 25px 21px;
  }
  
  .author-profile__body,
  .book-info__body {
    flex-direction: column;
  }
  
  .author-profile img {
    width: 120px;
    height: 140px;
  }
  
  .book-info img {
    width: 110px;
    height: 150px;
  }
}


/* ==================================================
   お問い合わせフォーム
================================================== */

/*-------------------------------------------------
問合せフォーム
-------------------------------------------------*/
.inquiry {
  position: relative;
  padding: 80px 0 90px;
}

.inquiry__inner {
  position: relative;
  z-index: 2;
  max-width: 860px;
}

.inquiry__heading {
  margin-bottom: 38px;
  text-align: center;
}

.inquiry__eyebrow {
  margin: 0 0 8px;
  color: var(--navy);
  font-size: .72rem;
  font-weight: 700;
  letter-spacing: .2em;
}

.inquiry__lead {
  margin: 16px 0 0;
  font-size: .88rem;
  line-height: 1.9;
}

.inquiry-form {
  padding: clamp(26px, 5vw, 52px);
  border: 1px solid var(--line);
  border-radius: 6px;
  background: rgba(255, 255, 255, .4);
  box-shadow: 0 8px 24px rgba(43, 32, 18, .08);
}

.inquiry-form__list {
  margin: 0;
}

.inquiry-form__item {
  display: flex;
  align-items: flex-start;
  padding: 20px 0;
  border-bottom: 1px dotted var(--line);
}

.inquiry-form__item:first-child {
  padding-top: 0;
}

.inquiry-form__item dt {
  display: flex;
  flex: 0 0 190px;
  align-items: center;
  gap: 10px;
  padding-top: 13px;
  color: var(--navy);
  font-weight: 700;
}

.inquiry-form__item dd {
  flex: 1;
  min-width: 0;
  margin: 0;
}

.required {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 38px;
  padding: 3px 7px;
  border-radius: 2px;
  color: #fff;
  background: var(--red);
  font-size: .65rem;
  line-height: 1.2;
}

.inquiry-form input,
.inquiry-form textarea {
  width: 100%;
  padding: 13px 15px;
  border: 1px solid var(--line);
  border-radius: 3px;
  color: var(--ink);
  background: rgba(255, 255, 255, .75);
  font: inherit;
  line-height: 1.6;
  transition:
    border-color .2s,
    background-color .2s,
    box-shadow .2s;
}

.inquiry-form input::placeholder,
.inquiry-form textarea::placeholder {
  color: rgba(40, 35, 29, .45);
}

.inquiry-form input:focus,
.inquiry-form textarea:focus {
  border-color: var(--navy);
  outline: none;
  background: #fff;
  box-shadow: 0 0 0 3px rgba(16, 46, 89, .1);
}

.inquiry-form textarea {
  min-height: 180px;
  resize: vertical;
}

.inquiry-form__notice {
  margin: 24px 0 0;
  font-size: .72rem;
  line-height: 1.8;
  text-align: center;
}

.inquiry-form__buttons {
  display: flex;
  justify-content: center;
  margin-top: 28px;
}

.inquiry-form__submit {
  min-width: 280px;
  border: 0;
  cursor: pointer;
}

/* Mailform Proのエラー表示 */
.inquiry-form .mfp_err {
  margin-top: 6px;
  color: var(--red);
  font-size: .75rem;
  line-height: 1.6;
}


/* ==================================================
   購入CTA
================================================== */

.purchase {
  padding: 58px 0 64px;
  text-align: center;
  overflow: visible;
}

.purchase__inner {
  position: relative;
  z-index: 2;
}

.purchase h2 {
  margin-bottom: 5px;
}

.purchase p {
  margin: 0 0 24px;
}

.purchase__decoration--color {
  left: 0;
  bottom: 0;
  width: 640px;
  height: 640px;
  background-image: url("../images/bg-footer-color.png");
  background-position: left bottom;
  opacity: .5;
}

.purchase__decoration--book {
  right: 0;
  bottom: 0;
  width: 380px;
  height: 380px;
  background-image: url("../images/bg-footer-book.png");
  background-position: right bottom;
  opacity: .5;
}

/* 購入CTA：スマートフォン */

@media (max-width: 600px) {
  .purchase {
    padding: 52px 0 92px;
  }
  
  /*.purchase__decoration--cans,
  .purchase__decoration--brush {
    width: 145px;
    height: 120px;
    opacity: .65;
  }*/
  
  .purchase p {
    padding-inline: 10px;
  }
}


/* ==================================================
   フッター
================================================== */

.footer {
  padding: 30px 32px;
  color: #4b463e;
  background: var(--paper);
  border-top: 1px solid var(--line);
  text-align: center;
}

.footer nav {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 9px 28px;
  margin-bottom: 14px;
  font-size: .72rem;
}

.footer small {
  font-size: .67rem;
}

/* フッター：スマートフォン */

@media (max-width: 600px) {
  .footer {
    padding-inline: 20px;
  }
}


/* ==================================================
   アクセシビリティ
================================================== */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    transition-duration: .01ms !important;
  }
}