/* もくじページ */
.acc-wrap {
  padding-bottom: 40px;
  padding-top: 10px;
}

header .back {
  background-image: none;
  pointer-events: none;
  visibility: hidden;
}

main.mokuji {
  position: absolute;
  width: 100%;
  height: calc(100% - 73px);
  top: 73px;
}

@supports (padding-top: env(safe-area-inset-top)) {
  main.mokuji {
    top: calc(73px + env(safe-area-inset-top));
    height: calc(100vh - 73px - env(safe-area-inset-top));
  }
}

/* .has-zero-safe-area main.mokuji {
  top: calc(73px + 20px);
  height: calc(100vh - 73px - 20px);
} */

main.mokuji #contents {
  overflow-y: scroll;
  scrollbar-width: none;
}

.book-index-sublist {
  font-family: "UDDigi";
  margin: 0;
  padding: 0;
  list-style: none;
  max-height: 0;
  overflow: hidden;
  color: transparent;
}

.book-index-sublist > li {
  border-bottom: 1px solid var(--color);
  position: relative;
}

.book-index-sublist > li > a:hover {
  background-color: #f7f8f8;
}

.book-index-sublist > li > a:focus-visible {
  background-color: #f7f8f8;
}

.book-index-sublist > li::before {
  content: "";
  position: absolute;
  top: 10px;
  left: 11px;
  width: 5px;
  height: 27px;
  background: var(--color);
  border-radius: 6px;
  z-index: 1;
}

.book-index-sublist > li:last-child {
  border-bottom: none;
}

.book-index-sublist > li > a {
  position: relative;
  display: flex;
  align-items: center;
  height: 48px;
  padding: 0 30px 0 30px;
  font-size: var(--font-size-sublist);
  color: var(--black-color);
  line-height: 1.3;
  text-decoration: none;
}

@media (max-width: 767px) {
  .book-index-sublist > li > a {
    font-size: var(--font-size-sublist-sm);
  }
}

.book-index-sublist > li > a::after {
  content: "";
  display: block;
  width: 48px;
  height: 48px;
  position: absolute;
  right: -3px;
  top: 0;
  bottom: 0;
  margin: auto;
  background-image: url(../images/accordion_icon.svg);
  background-size: 13px 7px;
  background-position: center center;
  background-repeat: no-repeat;
  transform: rotate(-90deg);
}

/*----------------------------------------------------------------
  color / font-size / padding
-----------------------------------------------------------------*/
/* コンテンツ色 */
:root {
  --color-orange: #f3981f;
  --color-green: #6dbb4f;
  --color-blue: #49ace2;
  --color-starter: #f9ce0c;
  --color-words-and-sounds: #f9ce0c;
  --color-take-action: #e60012;
  --color-language-focus: #115fad;
  --color-project: #f4e000;
  --color-reading: #a5a7b8;
  --color-contents: #ea5350;
  --color-dictionary-btn: #1971FF;
  --color-pronunciation-btn: #FF4B00;
  --padding-lesson: 28px 24px; /* 修正前: 24px */
  --padding-others: 15px 24px; /* 修正前: 24px */
  --padding-sm-lesson: 18px 15px; /* 修正前: 15px */
  --padding-sm-others: 5px 15px;
  --font-size-icon-lesson: 40px;
  --font-size-icon-others: 30px; /* 修正前: 40px */
  --font-size-icon-expand-lesson: 56px;
  --font-size-icon-expand-others: 46px; /* 修正前: 56px */
  --font-size-title-lesson: 30px; /* 修正前: 28px */
  --font-size-title-others: 24px;
  --font-size-title-sm-lesson: 22px; /* 修正前: 18px */
  --font-size-title-sm-others: 18px;
  --font-size-sublist-lesson: 24px; /* 修正前: 18px */
  --font-size-sublist-others: 18px;
  --font-size-sublist-sm-lesson: 20px; /* 修正前: 18px */
  --font-size-sublist-sm-others: 18px;
  --padding: var(--padding-others);
  --padding-sm: var(--padding-sm-others);
  --font-size-icon: var(--font-size-icon-others);
  --font-size-icon-expand: var(--font-size-icon-expand-others);
  --font-size-title: var(--font-size-title-others);
  --font-size-title-sm: var(--font-size-title-sm-others);
  --font-size-sublist: var(--font-size-sublist-others);
  --font-size-sublist-sm: var(--font-size-sublist-sm-others);
}

/* Lesson */
body.nc1 .accordion-lesson1,
body.nc1 .accordion-lesson2,
body.nc1 .accordion-lesson3,
body.nc2 .accordion-lesson1,
body.nc2 .accordion-lesson2,
body.nc2 .accordion-lesson3,
body.nc3 .accordion-lesson1,
body.nc3 .accordion-lesson2,
body.nc3 .accordion-lesson3 {
  --color: var(--color-orange);
}

.accordion-starter {
  --color: #f9ce0c;
}
.accordion-words-and-sounds {
  --color: #f9ce0c;
}
.accordion-take-action {
  --color: #e60012;
}
.accordion-language-focus {
  --color: #115fad;
}
.accordion-project {
  --color: #f4e000;
}
.accordion-reading {
  --color: #a5a7b8;
}
.accordion-contents {
  --color: #ea5350;
}

.accordion-lesson1,
.accordion-lesson2,
.accordion-lesson3 {
  --padding: var(--padding-lesson);
  --padding-sm: var(--padding-sm-lesson);
  --font-size-icon: var(--font-size-icon-lesson);
  --font-size-icon-expand: var(--font-size-icon-expand-lesson);
  --font-size-title: var(--font-size-title-lesson);
  --font-size-title-sm: var(--font-size-title-sm-lesson);
  --font-size-sublist: var(--font-size-sublist-lesson);
  --font-size-sublist-sm: var(--font-size-sublist-sm-lesson);
}

.accordion {
  position: relative;
  display: block;
  color: #443849;
}
.accordion__tab {
  display: flex;
  align-items: flex-end;
  justify-content: center;
  position: relative;
  z-index: 2;
  width: 120px;
  height: 24px;
  font-size: 16px;
  padding-right: 10px;
  color: var(--color);
}
.accordion__tab::before {
  content: "";
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
  z-index: -1;
  background: var(--color);
  transform: scaleY(1.3) perspective(0.6em) rotateX(5deg);
  transform-origin: bottom left;
  border-radius: calc(var(--accordion-border-radius) + 4px) 8px 0 0;
}
.accordion__tab::after {
  content: "";
  position: absolute;
  z-index: -1;
  top: 4px;
  right: 6px;
  bottom: 0;
  left: 4px;
  background-color: #fff;
  transform: scaleY(1.3) perspective(0.6em) rotateX(5deg);
  transform-origin: bottom left;
  border-radius: var(--accordion-border-radius) 8px 0 0;
}
.accordion-lesson1 .accordion__tab::after,
.accordion-lesson2 .accordion__tab::after,
.accordion-lesson3 .accordion__tab::after {
  background-color: var(--color-orange);
}
.accordion-lesson1 .accordion__tab,
.accordion-lesson2 .accordion__tab,
.accordion-lesson3 .accordion__tab {
  color: #fff;
}

.accordion__open,
.accordion__close {
  display: none;
}
.accordion__wrapper {
  position: relative;
  width: 100%;
  height: 100%;
  padding: var(--padding);
  box-sizing: border-box;
  background: #fff;
  border-radius: var(--accordion-border-radius);
  border-top-left-radius: 0;
  cursor: pointer;
  border: solid 4px var(--color);
  box-shadow: 6px 6px 10px 0px rgba(0, 0, 0, 0.4);
}
@media (max-width: 767px) {
  .accordion__wrapper {
    padding: var(--padding-sm);
  }
}
.accordion__box {
  margin: 0;
}
.accordion__patition {
  position: relative;
  z-index: 2;
  box-sizing: border-box;
  width: 100%;
}
.accordion__number {
  position: absolute;
  top: 0;
  left: 0;
  display: flex;
  align-items: center;
  width: 50px;
  height: var(--font-size-icon);
  margin-left: 15px;
  margin-right: 16px;
  font-size: var(--font-size-icon);
  color: var(--color);
}
.accordion__number .fa-solid {
  margin-left: -6px;
}
.num_line {
  margin-left: 5px;
}
.num_line::before {
  content: "";
  position: absolute;
  left: 84px;
  width: 5px;
  background: var(--color);
  border-radius: 6px;
  height: 27px;
}
.page_range {
  display: none;
  position: absolute;
  bottom: -8px;
  left: 104px;
  width: 80px;
  height: 40px;
  font-size: 13px;
  line-height: 17px;
  overflow: hidden;
  color: var(--black-color);
}
.accordion__title {
  display: flex;
  align-items: center;
  box-sizing: border-box;
  padding-left: 70px;
  font-size: var(--font-size-title);
  font-weight: bold;
  line-height: 1.3;
  min-height: 40px;
}
@media (max-width: 767px) {
  .accordion__title {
    font-size: var(--font-size-title-sm);
  }
}
.accordion__title::before {
  content: "";
  position: absolute;
  bottom: -12px;
  right: 0;
  width: 0;
  height: 3px;
  background: var(--color);
}
.accordion__text {
  position: relative;
  z-index: 2;
  margin: 0;
  font-size: 14px;
  line-height: 1.6;
  max-height: 0;
  overflow: hidden;
  color: transparent;
}
.accordion__text::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: auto;
  width: 0;
  height: 100%;
  background: var(--color);
}
.text_color {
  color: #443849;
  max-height: 100%;
}
.accordion__button {
  position: absolute;
  z-index: 1;
  top: 4px;
  left: 4px;
  font-size: 14px;
  width: 0;
  height: 28px;
  overflow: hidden;
  cursor: pointer;
}
.accordion__button::before {
  content: "";
  position: absolute;
  z-index: 1;
  bottom: 0;
  right: 0;
  width: 100%;
  height: 100%;
  transform-origin: bottom right;
  transform: skew(30deg);
  border-radius: 0 6px 0 0;
  background: var(--color);
}
.accordion-lesson1 .accordion__button::before,
.accordion-lesson2 .accordion__button::before,
.accordion-lesson3 .accordion__button::before {
  background-color: #fff;
  border: 3px solid var(--color);
  border-bottom: none;
}
.accordion__buttonText {
  display: flex;
  align-items: center;
  justify-content: flex-end;
  position: absolute;
  z-index: 3;
  top: 3px;
  left: 0;
  width: 100%;
  height: 100%;
  box-sizing: border-box;
  padding-right: 40px;
  color: #fff;
}
.accordion-lesson1 .accordion__buttonText,
.accordion-lesson2 .accordion__buttonText,
.accordion-lesson3 .accordion__buttonText {
  color: var(--black-color);
}
.accordion__buttonText::before,
.accordion__buttonText::after {
  content: "";
  position: absolute;
  top: -3px;
  right: 24px;
  bottom: 0;
  margin: auto 0;
  width: 12px;
  height: 3px;
  background: #fff;
}
.accordion-lesson1 .accordion__buttonText::before,
.accordion-lesson1 .accordion__buttonText::after,
.accordion-lesson2 .accordion__buttonText::before,
.accordion-lesson2 .accordion__buttonText::after,
.accordion-lesson3 .accordion__buttonText::before,
.accordion-lesson3 .accordion__buttonText::after {
  background: var(--black-color);
}
.accordion__buttonText::before {
  transform: rotate(45deg);
}
.accordion__buttonText::after {
  transform: rotate(-45deg);
}
.accordion__open:checked ~ .accordion__wrapper {
  cursor: default;
}

.accordion__open:checked ~ .accordion__wrapper .accordion__number {
  animation: rotate 1s linear;
  animation-fill-mode: forwards;
}
@keyframes rotate {
  0% {
    transform: rotateY(0deg) scale(1);
    width: auto;
  }
  20% {
    transform: rotateY(360deg) scale(1.6);
    font-size: 56px;
    height: 56px;
  }
  60% {
    transform: rotateY(360deg) scale(1.6);
  }
  70% {
    transform: rotateY(360deg) scale(1);
    width: auto;
  }
  84% {
    transform: rotateY(360deg) scale(1);
    width: auto;
  }
  85% {
    transform: rotateY(360deg) scale(1);
    width: 100%;
  }
  100% {
    transform: rotateY(360deg) scale(1);
    width: 100%;
    font-size: 56px;
    height: 56px;
  }
}
.accordion__close:checked ~ .accordion__wrapper .accordion__number {
  font-size: var(--font-size-icon-expand);
  height: var(--font-size-icon-expand);
  animation: rotate_rev 0.2s 0.5s linear;
  animation-fill-mode: forwards;
}
@keyframes rotate_rev {
  0% {
    font-size: var(--font-size-icon-expand);
    height: var(--font-size-icon-expand);
  }
  100% {
    font-size: var(--font-size-icon);
    height: var(--font-size-icon);
  }
}

.accordion__open:checked ~ .accordion__wrapper .accordion__title::before {
  animation: title_line 0.5s 0.9s ease;
  animation-fill-mode: forwards;
}
@keyframes title_line {
  0% {
    width: 0;
  }
  100% {
    width: 100%;
  }
}
.accordion__close:checked ~ .accordion__wrapper .accordion__title::before {
  animation: title_line_rev 0.3s ease;
  animation-fill-mode: forwards;
}
@keyframes title_line_rev {
  0% {
    width: 100%;
  }
  100% {
    width: 0;
  }
}

.accordion__open:checked ~ .accordion__button {
  animation: close_button 0.5s 0.9s ease-out;
  animation-fill-mode: forwards;
}
@keyframes close_button {
  0% {
    width: 0;
  }
  100% {
    width: calc(100% - 24px - 4px);
  }
}
.accordion__close:checked ~ .accordion__button {
  animation: close_button_rev 0.3s ease-in;
  animation-fill-mode: forwards;
}
@keyframes close_button_rev {
  0% {
    width: calc(100% - 24px - 4px);
  }
  100% {
    width: 0;
  }
}

.semester-separator {
  border: none;
  border-top: 4px dotted #f3981f;
  width: 100%;
}

.airplane {
  background-color: var(--color);
  height: 35px;
  width: 35px;
  mask-repeat: no-repeat;
  mask-position: center;
  mask-image: url(../images/airplane.svg);
  position: absolute;
  left: -5px;
  top: 2px;
}

.star {
  background-color: var(--color);
  height: 30px;
  width: 35px;
  mask-repeat: no-repeat;
  mask-position: center;
  mask-image: url(../images/star.svg);
  position: absolute;
  left: -5px;
  top: 2px;
}

.contents {
  background-color: var(--color);
  height: 35px;
  width: 35px;
  mask-repeat: no-repeat;
  mask-position: center;
  mask-image: url(../images/contents.svg);
  position: absolute;
  left: -5px;
  top: 0px;
}

.reading {
  background-color: var(--color);
  height: 35px;
  width: 35px;
  mask-repeat: no-repeat;
  mask-position: center;
  mask-image: url(../images/reading.svg);
  position: absolute;
  left: -5px;
  top: 0px;
}

.num_line .star,
.num_line .airplane,
.num_line .contents,
.num_line .reading {
  height: 50px;
  width: 45px;
  position: absolute;
  left: 0px;
  top: 1px;
}

/* 上部のボタンエリア */
.btn-wrapper {
  max-width: 1000px;
  margin: 2rem auto;
  padding: 0 10px;
}

.dictionary-btn,
.pronunciation_check_btn {
  position: relative;
  width: 49%;
  box-sizing: border-box;
  border-radius: 0.5em;
  cursor: pointer;
  box-shadow: 6px 6px 10px 0px rgba(0, 0, 0, 0.4);
}

.dictionary-btn a,
.pronunciation_check_btn a {
  position: relative;
  padding: var( --padding-others);
  box-sizing: border-box;
  cursor: pointer;
}

.dictionary-btn i,
.pronunciation_check_btn i {
  width: 45px;
  height: 45px;
  position: absolute;
  right: 3px;
  top: 20px;
  color: #fff;
  font-size: 35px;
}

.dictionary-btn {
  background-color: var(--color-dictionary-btn);
}

.pronunciation_check_btn {
  background-color: var(--color-pronunciation-btn);
}

.dictionary-btn img,
.pronunciation_check_btn img {
  height: 45px;
  width: 45px;
}

.dictionary-btn span,
.pronunciation_check_btn span {
  margin-top: 2px;
  min-height: 46px;
  font-size: 27px;
  color: #fff;
  padding-left: 30px;
  line-height: 46px;
}

@media screen and (max-width: 767px) {
  .btn-wrapper {
    padding: 0 30px;
    justify-content: space-around!important;
  }

  .dictionary-btn,
  .pronunciation_check_btn {
    width: 84px;
    height: 84px;
    box-sizing: border-box;
    cursor: pointer;
  }

  .dictionary-btn a,
  .pronunciation_check_btn a {
    flex-direction: column;
    padding: 15px 5px;
    height: 84px;
  }

  .dictionary-btn img,
  .pronunciation_check_btn img {
    height: 35px;
    width: 35px;
  }

  .dictionary-btn span,
  .pronunciation_check_btn span {
    min-height: 25px;
    font-size: 14px;
    padding-left: 0;
    line-height: 25px;
  }
}