/* @override
	http://localhost/nttls/highschool-lesson/css/style.css */

@charset "UTF-8";

/* @group リセットCSS */

/* --------------------------------------------------------------------------------
   リセットCSS
   --------------------------------------------------------------------------------
     - マージン、パディング、ボーダーはすべて0
     - フォントサイズは 16px（1.4rem） に揃える
     - 見出し、em、strong、b、th は太字にする
     - テーブルはボーダーあり
     - など
   --------------------------------------------------------------------------------
   ＜補足＞
     - Meyresweb CSS Reset に一部 Normalize.css を足した感じ
     - Meyersweb CSS Reset : https://meyerweb.com/eric/tools/css/reset/
     - Normalize.css: https://necolas.github.io/normalize.css/
----------------------------------------------------------------------------------- */

html,
body,
div,
span,
applet,
object,
iframe,
h1,
h2,
h3,
h4,
h5,
h6,
p,
blockquote,
pre,
a,
abbr,
acronym,
address,
big,
cite,
code,
del,
dfn,
em,
img,
ins,
kbd,
q,
s,
samp,
small,
strike,
strong,
sub,
sup,
tt,
var,
b,
u,
i,
center,
dl,
dt,
dd,
ol,
ul,
li,
fieldset,
form,
label,
legend,
table,
caption,
tbody,
tfoot,
thead,
tr,
th,
td,
article,
aside,
canvas,
details,
embed,
figure,
figcaption,
footer,
header,
hgroup,
menu,
nav,
output,
ruby,
section,
summary,
time,
mark,
audio,
video {
  margin: 0;
  padding: 0;
  border: 0;
}

html {
  font-size: 62.5%; /* rootフォントサイズを10pxにする（16px * 62.55 = 10px） */
  -webkit-box-sizing: border-box;
          box-sizing: border-box;
}

*,
::before,
::after {
  -webkit-box-sizing: inherit;
          box-sizing: inherit;
  text-decoration: inherit; /* Inherit text-decoration and vertical align to ::before and ::after pseudo elements */
  vertical-align: inherit;
  -webkit-font-feature-settings: "palt";
          font-feature-settings: "palt";
}

body {
  font-family: -apple-system, BlinkMacSystemFont, "Hiragino Kaku Gothic ProN", Meiryo, "Helvetica Neue", Verdana, sans-serif;
  font-size: 1.6em; /* 16px（body で rem ではなく em を使うのはChromeのバグ対策） */
  line-height: 2;
  word-wrap: break-word;
  word-wrap: break-word;
  word-break: break-word;
  -webkit-text-size-adjust: 100%; /* スマホを横向きにしたとき等に文字サイズを自動調整しない（CSSの指定どおり） */
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

img {
  max-width: 100%;
  height: auto;
  line-height: 0;
  vertical-align: top;
  image-rendering: -webkit-optimize-contrast; /* Chromeで画像がぼやける現象を回避 */
}

ol,
ul {
  list-style: none;
}

h1,
h2,
h3,
h4,
h5,
h6 {
  font-size: 1.6rem;
  font-weight: bold;
}

b,
em,
strong {
  font-style: normal;
  font-weight: bold;
}

small {
  font-size: 80%;
}

/* sub, sup が行間に影響を及ぼすのを防ぐ */
sub,
sup {
  position: relative;
  margin-left: 0.15em;
  margin-right: 0.15em;
  font-size: 77%;
  line-height: 0;
  vertical-align: baseline;
}

sup {
  top: -0.5em;
}

sub {
  bottom: -0.25em;
}

hr {
  display: block;
  height: 1px;
  margin: 1em 0;
  border-top: 1px solid #ccc;
}

pre,
code,
kbd,
samp,
tt {
  font-family: monospace;
}

/* アンカー */
a {
  color: #03c;
  text-decoration: underline;
}

a:visited {
  color: #60a;
  text-decoration: underline;
}

a:hover {
  color: #f00;
  text-decoration: none;
}

a:focus {
  outline: none;
}

a:hover,
a:active {
  outline: none;
}

/* テーブル */
table {
  width: 100%;
  border-collapse: collapse;
  border-spacing: 0;
}

th,
td {
  padding: 0.5em 0.8em;
  border: 1px solid #ddd;
}

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

thead th {
  text-align: center;
  background-color: #DEE2E6;
}

tbody th {
  background-color: #f9f9f9;
}

/* フォーム */
[disabled] {
  cursor: default;
}

label {
  cursor: pointer;
}

button,
input,
select,
optgroup,
textarea {
  font-family: inherit;
  font-size: 100%;
}

button,
[type=button],
[type=reset],
[type=submit],
[role=button] {
  cursor: pointer;
  -webkit-appearance: button;
}

button::-moz-focus-inner,
[type=button]::-moz-focus-inner,
[type=reset]::-moz-focus-inner,
[type=submit]::-moz-focus-inner {
  /* Firefox で button 要素に CSS で消せない padding と border がつくのを消す (normalize.css) */
  border-style: none;
  padding: 0;
}

button:-moz-focusring,
[type=button]::-moz-focus-inner,
[type=reset]::-moz-focus-inner,
[type=submit]::-moz-focus-inner {
  /* 上で消したボーダーを outline として表示 */
  outline: 1px dotted ButtonText;
}

input[type=text],
input[type=email],
textarea {
  width: 100%;
  padding: 0.5rem;
  font-size: 1.6rem;
  line-height: 2.4rem;
  border-radius: 0.3rem;
  border: 1px solid #ddd;
}
input[type=text]:focus,
input[type=email]:focus,
textarea:focus {
  outline: #0072BC auto 2px;
}

textarea {
  display: block;
  overflow: auto;
  vertical-align: top;
}

input:invalid,
textarea:invalid {
  background-color: #f0dddd;
}

select {
  /* Style select like a standard input */
  -moz-appearance: none; /* Firefox 36+ */
  -webkit-appearance: none; /* Chrome 41+ */
}

select::-ms-expand {
  display: none; /* Internet Explorer 11+ */
}

select::-ms-value {
  color: currentColor; /* Internet Explorer 11+ */
}

::-webkit-file-upload-button {
  /* Correct the inability to style clickable types in iOS and Safari */
  -webkit-appearance: button;
  color: inherit;
  font: inherit; /* Change font properties to `inherit` in Chrome and Safari */
}

progress {
  /* Chrome, Firefox, Opera における調整 */
  vertical-align: baseline;
}

[type=number]::-webkit-inner-spin-button,
[type=number]::-webkit-outer-spin-button {
  /* Correct the cursor style of increment and decrement buttons in Chrome */
  height: auto;
}

[type=search] {
  /* Correct the odd appearance in Chrome and Safari */
  -webkit-appearance: textfield;
  /* Correct the outline style in Safari */
  outline-offset: -2px;
}

[type=search]::-webkit-search-decoration {
  /* Remove the inner padding in Chrome and Safari on macOS */
  -webkit-appearance: none;
}

/* アクセシビリティ */
[aria-busy=true] {
  /* Specify the progress cursor of updating elements */
  cursor: progress;
}

[aria-controls] {
  /* Specify the pointer cursor of trigger elements */
  cursor: pointer;
}

[aria-disabled=true] {
  /* Specify the unstyled cursor of disabled, not-editable, or otherwise inoperable elements */
  cursor: default;
}

/* 印刷用 */
@media print {
  thead {
    display: table-header-group;
  }
  tr,
  img {
    page-break-inside: avoid;
  }
  h1,
  h2,
  h3 {
    page-break-after: avoid;
  }
  img {
    max-width: 100% !important;
  }
  @page {
    margin: 1.2cm;
  }
}

/* --------------------------------------------------------------------------------
   フォント
   --------------------------------------------------------------------------------
    - -apple-system: Mac と iOS 用フォント SanFrancisco。ヒラギノに近いが欧文はヒラギノより良い
    - BlinkMacSystemFont: Chrome で SanFranciso を使いたいときの指定
----------------------------------------------------------------------------------- */

body {
  font-family: "游ゴシック体", YuGothic, "游ゴシック", "Yu Gothic", -apple-system, BlinkMacSystemFont, "Segoe UI", "Helvetica Neue", "Hiragino Sans", "Hiragino Kaku Gothic ProN", Meiryo, Helvetica, Arial, sans-serif;
  font-size: 1.6em; /* 14px（body で rem ではなく em を使うのはChromeのバグ対策） */
  letter-spacing: 0.05em;
  line-height: 2;
  color: #222222;
}

html {
  font-size: 62.55%; /* rootフォントサイズを9pxにする（16px * 62.55 = 10px） */
}
@media screen and (max-width: 1279px) {
  html {
    font-size: 60%;
  }
}
@media screen and (max-width: 1199px) {
  html {
    font-size: 56%;
  }
}
@media screen and (max-width: 1119px) {
  html {
    font-size: 50%;
  }
}
@media print, screen and (max-width: 959px) {
  html {
    font-size: 56%;
  }
}

/* --------------------------------------------------------------------------------
   リンクスタイル
----------------------------------------------------------------------------------- */

a:link {
  color: #0072BC;
}

a:visited {
  color: #00427E;
}

a:hover {
  text-decoration: none;
}

em {
  color: #333;
}

strong {
  color: #C73D3D;
}

/* --------------------------------------------------------------------------------
   ベースのスタイル
   --------------------------------------------------------------------------------
    - 要素セレクタの初期値を定義
    - リセットCSSを上書きするイメージ
----------------------------------------------------------------------------------- */

/* コンテンツ量が少ないときも、フッタをウィンドウ下部に固定するための設定 */
html {
  height: 100%;
  scroll-behavior: smooth;
}

@media all and (-ms-high-contrast: none) {
  html {
    min-width: 1024px;
  }
}

body {
  display: flex;
  flex-direction: column;
}

body > * {
  flex-shrink: 0;
}

/* --------------------------------------------------------------------------------
   .container: コンテナ
----------------------------------------------------------------------------------- */

.container {
  max-width: 1440px;
  margin: auto;
  padding: 16px;
}

/* --------------------------------------------------------------------------------
   .page-header: ヘッダ
----------------------------------------------------------------------------------- */

.page-header {
  position: relative;
  width: 1440px;
  height: 0;
  margin: auto;
  padding-top: 280px;
  overflow: hidden;
  background: url(../images/menu-bg.png) no-repeat center;
  background-size: 100%;
}

.page-header .nav {
  position: absolute;
  left: 0;
  top: 48%;
  display: flex;
  justify-content: center;
  gap: 57.6px; /* 1440 * 4% = 57.6px */
  width: 100%;
  height: 52%;
}

.page-header .nav li a {
  display: block;
  transition: all .2s linear;
}

.page-header .nav li a:hover {
  transform: scale(1.1);
}

@media screen and (max-width: 1440px) {
  .page-header {
    width: 100%;
    padding-top: 19.43%; /* 1440 * 19.43% = 280px */
  }

  .page-header .nav {
    gap: 4vw;
  }

  .page-header li a img {
    width: auto;
    height: 7.55vw;
  }
}

/* --------------------------------------------------------------------------------
   .nav-sticky: sticky ナビゲーション
----------------------------------------------------------------------------------- */

.nav-sticky {
  display: none;
}

.nav-sticky.is-active {
  z-index: 10;
  display: flex;
  justify-content: center;
  align-items: center;
  gap: 32px;
  position: fixed;
  left: 0;
  top: 0;
  width: 100%;
  height: 64px;
  margin: auto;
  background: url(../images/nav-bg.png) no-repeat center;
  background-size: cover;
  box-shadow: 0 0 5px rgba(0, 0, 0, .35);
}

.nav-sticky.is-active li a {
  display: block;
  height: 48px;
  transition: all .2s linear;
}

.nav-sticky.is-active li a img {
  height: 48px;
}

.nav-sticky.is-active li a:hover {
  transform: scale(1.1);
}

@media screen and (max-width: 480px) {
  .nav-sticky.is-active {
    gap: 20px;
    height: 48px;
  }

  .nav-sticky.is-active li a {
    height: 32px;
  }

  .nav-sticky.is-active li a img {
    height: 32px;
  }
}

/* --------------------------------------------------------------------------------
   .content: コンテンツのラッパー
----------------------------------------------------------------------------------- */

.content {
  padding: 60px 0;
}

.content:first-child {
  padding-top: 40px;
}

@media screen and (max-width: 640px) {
  .content:first-child {
    padding-top: 20px;
  }
}

/* --------------------------------------------------------------------------------
   .content-header: コンテンツヘッダ
----------------------------------------------------------------------------------- */

.content-header h1 {
  padding: 16px 32px;
  font-size: 32px;
  line-height: 1.2;
  letter-spacing: .08em;
  color: #fff;
  border-radius: 8px;
  background-image: linear-gradient(to right, #00469C 0, #009EE8 100%);
}

.content.is-jouhou-2 .content-header h1 {
  background-image: linear-gradient(to right, #00551D 0, #19A337 100%);
}

.content-header h1 br {
  display: none;
}

@media screen and (max-width: 1024px) {
  .content-header h1 {
    padding: 16px 24px;
    font-size: 24px;
    letter-spacing: 0;
  }
}

@media screen and (max-width: 640px) {
  .content-header h1 br {
    display: block;
  }
}

@media screen and (max-width: 480px) {
  .content-header h1 {
    padding: 8px 16px;
    font-size: 18px;
  }
}

/* --------------------------------------------------------------------------------
   .lesson: レッスン
----------------------------------------------------------------------------------- */

.lesson {
  margin-top: 48px;
}

.lesson h2 {
  margin-bottom: 16px;
  padding-bottom: 8px;
  font-size: 32px;
  line-height: 1.2;
  color: #1B228D;
  border-bottom: 1px solid #1B228D;
}

.content.is-jouhou-2 .lesson h2 {
  color: #007C2F;
  border-bottom: 1px solid #007C2F;
}

@media screen and (max-width: 1024px) {
  .lesson {
    margin-top: 32px;
  }

  .lesson h2 {
    font-size: 24px;
  }
}

@media screen and (max-width: 480px) {
  .lesson {
    margin-top: 32px;
  }

  .lesson h2 {
    font-size: 18px;
  }
}

/* --------------------------------------------------------------------------------
   .lesson-sub-category: レッスンのサブカテゴリ
----------------------------------------------------------------------------------- */

.lesson-sub-category {
  margin: 36px 0;
}

.lesson-sub-category h3 {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 24px;
  line-height: 1.2;
  color: #1B228D;
}

.lesson-sub-category h3::before {
  content: '';
  display: block;
  width: 3px;
  height: 48px;
  background-color: #1B228D;
}

@media screen and (max-width: 1024px) {
  .lesson-sub-category {
    margin: 24px 0;
  }

  .lesson-sub-category h3 {
    font-size: 20px;
  }

  .lesson-sub-category h3::before {
    height: 36px;
  }
}

@media screen and (max-width: 480px) {
  .lesson-sub-category {
    margin: 16px 0;
  }

  .lesson-sub-category h3 {
    gap: 8px;
    font-size: 16px;
  }

  .lesson-sub-category h3::before {
    height: 24px;
  }
}

/* --------------------------------------------------------------------------------
   .lesson-list: レッスン一覧
----------------------------------------------------------------------------------- */

.lesson-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: flex-start;
  gap: 24px 8px;
  margin-top: 24px;
}

.lesson-list > li {
  width: calc(25% - 6px);
}

@media screen and (max-width: 1024px) {
  .lesson-list {
    gap: 16px 8px;
    margin-top: 16px;
  }

  .lesson-list > li {
    width: calc(33.333% - 6px);
  }
}

@media screen and (max-width: 640px) {
  .lesson-list > li {
    width: calc(50% - 8px);
  }
}

@media screen and (max-width: 480px) {
  .lesson-list {
    flex-direction: column;
  }

  .lesson-list > li {
    width: 100%;
  }
}

/* --------------------------------------------------------------------------------
   .lesson-item: レッスンアイテム
----------------------------------------------------------------------------------- */

.lesson-item {
  display: block;
  width: 100%;
  height: 100%;
  background-color: #fff;
  transition: all .2s linear;
}

a.lesson-item,
a.lesson-item:visited {
  text-decoration: none;
  color: #333;
}

.lesson-item:hover {
  transform: scale(1.05);
  color: #05a;
}

.lesson-item:hover em {
  color: #05a;
}

.lesson-item > img {
  display: block;
  width: 100%;
  height: auto;
  aspect-ratio: 1 / 0.5625;
  border-radius: 8px;
}

.lesson-item h4 {
  padding: 8px;
  font-size: 14px;
  font-weight: normal;
  line-height: 1.4;
}

.lesson-item h4 em {
  display: block;
  margin-top: 4px;
  font-size: 120%;
  font-weight: bold;
}

@media screen and (max-width: 1024px) {
  .lesson-item h4 {
    font-size: 12px;
  }
}

@media screen and (max-width: 640px) {
  .lesson-item:hover {
    transform: none;
    box-shadow: none;
  }
}

@media screen and (max-width: 480px) {
  .lesson-item {
    display: flex;
    gap: 8px;
    width: 100%;
  }

  .lesson-item > img {
    width: 50%;
  }

  .lesson-item h4 {
    padding: 0;
  }
}

/* --------------------------------------------------------------------------------
   .pagetop: ページトップボタン
----------------------------------------------------------------------------------- */

.pagetop {
  position: fixed;
  bottom: -100px;
  right: 20px;
  padding: 0;
  outline: none;
  border: 0;
  background: none;
  transition: all .2s linear;
}

.pagetop img {
  width: 72px;
  transition: all .2s linear;
}

.pagetop:hover img {
  width: 90px;
}

.pagetop.is-active {
  bottom: 20px;
}

@media screen and (max-width: 640px) {
  .pagetop {
    right: 10px;
  }

  .pagetop img,
  .pagetop:hover img {
    width: 48px;
  }

  .pagetop.is-active {
    bottom: 10px;
  }
}

/* --------------------------------------------------------------------------------
   footer: フッタ
----------------------------------------------------------------------------------- */

footer {
  margin-top: 80px;
  padding: 40px 16px 24px;
  line-height: 1.2;
  text-align: center;
  color: #999;
  border-top: 1px solid #ddd;
}

@media screen and (max-width: 1024px) {
  footer {
    margin-left: -16px;
    margin-right: -16px;
    margin-top: 40px;
    padding: 24px 16px 8px;
    font-size: 10px;
  }
}