/* 第174回：第171回の紅葉素材と、3級＝ピンク・2級＝グリーンを継承 */
:root {
  --ink:#3b302b;
  --muted:#766960;
  --red:#ad3c24;
  --cream:#fffcf6;
  --line:#e9dfd2;
  --pink:#b93761;
  --green:#24704d;
}
html {
  scroll-behavior:smooth;
  scroll-padding-top:24px;
}
body {
  font-family:-apple-system,BlinkMacSystemFont,"Hiragino Kaku Gothic ProN","Yu Gothic",Meiryo,sans-serif;
  color:var(--ink);
  background:#fff;
  line-height:1.85;
  font-size:16px;
}
a,button {
  -webkit-tap-highlight-color:transparent;
}
a:focus-visible,button:focus-visible {
  outline:3px solid #235caa;
  outline-offset:5px;
}
a:hover {
  text-decoration:underline;
  text-underline-offset:4px;
}
.container {
  width:min(1080px,calc(100% - 64px));
  margin-inline:auto;
}
.site-header {
  background:#fff;
}
.header-inner {
  max-width:1200px;
  padding:26px 32px;
  margin:auto;
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:24px;
}
.logo {
  width:230px;
  height:auto;
}
.header-inner nav {
  display:flex;
  gap:28px;
  font-size:14px;
  font-weight:700;
}
.skip-link {
  position:absolute;
  top:-100px;
  left:12px;
  z-index:20;
  background:#fff;
  padding:10px 20px;
}
.skip-link:focus {
  top:10px;
}
.mobile-only {
  display:none;
}
.hero {
  background:#fffaf1 url(../img/mv-bg-sp2.jpg) center/100% 100% no-repeat;
  text-align:center;
  border-bottom:1px solid #eddcc3;
}
.hero-inner {
  max-width:1100px;
  margin:auto;
  padding:72px 32px 94px;
}
.hero-eyebrow {
  display:inline-block;
  background:#ffffffed;
  border-radius:30px;
  padding:3px 14px;
  font-weight:700;
  font-size:17px;
  letter-spacing:.1em;
}
.edition {
  display:flex;
  align-items:baseline;
  justify-content:center;
  gap:5px;
  line-height:1.3;
  margin-top:14px;
  font-size:26px;
  font-weight:800;
  color:var(--red);
}
.edition>span {
  align-self:center;
  background:var(--red);
  color:#fff;
  border-radius:50%;
  font-size:17px;
  line-height:1;
  padding:18px 11px;
  margin-right:15px;
  transform:rotate(-8deg);
}
.edition strong {
  font-size:64px;
  letter-spacing:-.035em;
}
.hero-subtitle {
  display:block;
  font-size:clamp(24px,3.5vw,40px);
  letter-spacing:.08em;
  line-height:1.5;
  margin:8px 0 17px;
}
.hero-subtitle b {
  font-size:1.2em;
}
.hero-title {
  display:flex;
  justify-content:center;
  gap:17px;
}
.hero-title>span {
  display:grid;
  place-items:center;
  width:110px;
  height:110px;
  border-radius:50%;
  background:var(--red);
  color:#fff;
  font-weight:900;
  font-size:65px;
  line-height:1;
  box-shadow:0 5px 0 #ebd2b9;
}
.hero-message {
  font-size:26px;
  font-weight:800;
  letter-spacing:.08em;
  margin-top:27px;
}
.hero-description {
  font-size:15px;
  margin:9px 0 23px;
}
.hero-actions {
  display:flex;
  gap:16px;
  justify-content:center;
}
.grade-button {
  display:flex;
  align-items:center;
  justify-content:space-between;
  width:255px;
  padding:12px 22px;
  border-radius:7px;
  color:#fff;
  font-weight:700;
  box-shadow:0 4px 0 rgba(59,48,43,.18);
  transition:transform .2s;
}
.grade-button:hover {
  transform:translateY(-2px);
  text-decoration:none;
  filter:brightness(1.08);
}
.grade-button strong {
  font-size:25px;
  margin-left:8px;
}
.grade3-button {
  background:var(--pink);
}
.grade2-button {
  background:var(--green);
}
.hero-note {
  display:inline-block;
  background:#ffffffed;
  border-radius:30px;
  padding:2px 12px;
  font-size:12px;
  color:#5f4c3a;
  margin-top:14px;
}
.intro {
  text-align:center;
  padding-top:40px;
  padding-bottom:42px;
  font-size:15px;
}
.share {
  display:flex;
  justify-content:center;
  align-items:center;
  gap:10px;
  font-size:12px;
  margin-top:20px;
  color:var(--muted);
}
.share a {
  background:#262626;
  color:#fff;
  padding:1px 16px;
  border-radius:4px;
  font-weight:700;
}
.share .line-share {
  background:#087c31;
}
.section-heading {
  text-align:center;
  margin-bottom:28px;
}
.eyebrow {
  color:var(--red);
  font-size:12px;
  letter-spacing:.19em;
  font-weight:800;
  margin-bottom:7px;
}
.section-heading h2 {
  font-size:28px;
  letter-spacing:.04em;
  font-weight:800;
  line-height:1.5;
}
.section-heading>p:last-child:not(.eyebrow) {
  margin-top:12px;
  font-size:14px;
  color:var(--muted);
}
.guide {
  border-top:1px solid var(--line);
  padding-top:34px;
  padding-bottom:52px;
}
.steps {
  padding:0;
  list-style:none;
  display:grid;
  grid-template-columns:repeat(3,1fr);
  gap:30px;
}
.steps li {
  display:flex;
  align-items:flex-start;
  gap:13px;
}
.step-number {
  font-family:Georgia,serif;
  font-style:italic;
  font-size:33px;
  line-height:1.2;
  color:#bb7139;
  border-bottom:2px solid #ddb783;
}
.steps h3 {
  font-size:16px;
  margin-bottom:6px;
}
.steps p {
  font-size:13px;
  color:var(--muted);
  line-height:1.9;
}
.materials {
  background:var(--cream);
  border-block:1px solid var(--line);
  padding:54px 0;
}
.javascript-note {
  padding:13px 22px;
  background:#fff4df;
  border:1px solid #e6c997;
  border-radius:6px;
  font-size:14px;
  margin-bottom:26px;
  text-align:center;
}
.grade-grid {
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:30px;
}
.grade-card {
  --accent:var(--pink);
  --tint:#fcf1f5;
  scroll-margin-top:24px;
  border:1px solid #e5d2d9;
  border-top:0;
  border-radius:13px;
  overflow:hidden;
  background:#fff;
  box-shadow:0 7px 20px #4b321008;
  min-width:0;
}
.grade2 {
  --accent:var(--green);
  --tint:#edf6ef;
  border-color:#cfded3;
}
.grade-heading {
  background:var(--accent);
  color:#fff;
  display:flex;
  justify-content:space-between;
  align-items:center;
  padding:21px 28px;
}
.grade-heading p {
  font-size:12px;
  letter-spacing:.06em;
}
.grade-heading h3 {
  font-size:24px;
  line-height:1.5;
  font-weight:700;
}
.grade-heading h3 strong {
  font-size:49px;
  margin-left:10px;
  line-height:1.2;
}
.grade-heading h3 strong span {
  font-size:28px;
}
.free-label {
  border:1px solid #ffffff8c;
  border-radius:50%;
  display:grid;
  place-content:center;
  width:64px;
  height:64px;
  line-height:1.5;
  text-align:center;
  font-size:13px;
  font-weight:700;
}
.grade-content {
  padding:28px;
}
.resource-heading {
  font-size:17px;
  display:flex;
  gap:12px;
  align-items:center;
  margin-bottom:16px;
}
.step-label {
  font-size:10px;
  letter-spacing:.05em;
  color:var(--accent);
  border:1px solid currentColor;
  line-height:1.5;
  padding:3px 6px;
  white-space:nowrap;
}
.download-list {
  display:grid;
  gap:11px;
}
.download-button {
  display:flex;
  align-items:center;
  gap:14px;
  border:1px solid var(--accent);
  color:var(--accent);
  border-radius:7px;
  padding:13px 17px;
  min-height:78px;
  background:#fff;
  line-height:1.5;
}
.download-button[href]:hover {
  background:var(--tint);
  text-decoration:none;
}
.download-button strong {
  font-size:17px;
}
.download-button small {
  display:block;
  font-size:11px;
  margin-top:3px;
}
.pdf-icon {
  border:1.5px solid currentColor;
  border-radius:2px;
  align-self:center;
  padding:8px 4px;
  font-size:10px;
  font-weight:800;
  line-height:1;
}
.download-arrow {
  margin-left:auto;
  font-size:24px;
}
.resource-note {
  font-size:11px;
  color:var(--muted);
  margin-top:9px;
}
.timer-link {
  display:flex;
  align-items:center;
  gap:12px;
  padding:16px 0 22px;
  border-bottom:1px dashed var(--line);
  font-weight:700;
  font-size:14px;
  color:var(--accent);
  line-height:1.65;
}
.timer-link small {
  display:block;
  color:var(--muted);
  font-size:11px;
  font-weight:400;
}
.timer-link>span:last-child {
  margin-left:auto;
}
.play-icon {
  display:grid;
  place-items:center;
  border:1px solid currentColor;
  border-radius:50%;
  width:30px;
  height:30px;
  font-size:10px;
  flex-shrink:0;
  padding-left:2px;
}
.lecture {
  padding:25px 0;
}
.video-panel {
  aspect-ratio:16/9;
  background:var(--tint);
  border:1px solid var(--line);
  border-radius:6px;
  overflow:hidden;
}
.video-cover {
  height:100%;
  display:flex;
  flex-direction:column;
  align-items:center;
  justify-content:center;
  text-align:center;
  padding:18px;
  color:var(--muted);
}
.video-cover>span {
  display:grid;
  place-items:center;
  width:46px;
  height:46px;
  padding-left:3px;
  border-radius:50%;
  background:#fff;
  color:var(--accent);
  font-size:15px;
  margin-bottom:10px;
}
.video-cover strong {
  font-size:15px;
}
.video-cover p {
  font-size:12px;
  margin-top:3px;
}
.video-panel iframe {
  width:100%;
  height:100%;
  display:block;
  border:0;
}
.youtube-link {
  display:inline-block;
  text-decoration:underline;
  text-underline-offset:3px;
  font-size:14px;
  color:var(--accent);
  font-weight:700;
  margin-top:12px;
}
.video-tabs {
  display:flex;
  flex-wrap:wrap;
  gap:6px;
  margin-bottom:12px;
}
.video-tabs button {
  background:#fff;
  border:1px solid var(--accent);
  border-radius:4px;
  padding:7px 10px;
  color:var(--accent);
  font-size:12px;
  min-height:38px;
}
.video-tabs button[aria-selected="true"] {
  background:var(--accent);
  color:#fff;
}
.book-link {
  display:block;
  position:relative;
  background:var(--tint);
  color:var(--accent);
  padding:13px 18px;
  font-weight:700;
  border-radius:6px;
  font-size:14px;
}
.book-link>span {
  position:absolute;
  right:18px;
  top:20px;
  font-size:20px;
}
.book-link small {
  display:block;
  font-weight:400;
  font-size:10px;
}
.cbt-link {
  max-width:640px;
  display:flex;
  align-items:center;
  justify-content:space-between;
  background:#fff;
  border:1px solid #b09c82;
  border-radius:8px;
  margin:32px auto 0;
  padding:17px 26px;
  font-weight:700;
  font-size:18px;
}
.cbt-link small {
  display:block;
  font-size:12px;
  font-weight:400;
}
.cbt-link>span:last-child {
  font-size:24px;
}
.notes {
  padding-top:46px;
  padding-bottom:50px;
}
.notes h2 {
  font-size:19px;
  border-left:4px solid var(--red);
  padding-left:14px;
  line-height:1.5;
  margin-bottom:19px;
}
.notes ul {
  padding-left:1.3em;
  font-size:13px;
  color:#60564f;
}
.notes li+li {
  margin-top:9px;
}
.notes a {
  color:#365f8e;
  text-decoration:underline;
  text-underline-offset:3px;
}
.important {
  color:#ae302e;
  font-weight:700;
}
.course {
  background:#f2eee8;
  border-block:1px solid var(--line);
  padding:48px 0;
}
.course-inner {
  display:grid;
  grid-template-columns:1fr 1fr;
  gap:55px;
  align-items:center;
}
.course h2 {
  font-size:29px;
  line-height:1.65;
  letter-spacing:.04em;
  margin-bottom:17px;
}
.course-copy>p:not(.eyebrow) {
  font-size:13px;
  line-height:2;
}
.course figure {
  padding:16px 16px 10px;
  background:#fff;
  box-shadow:0 5px 18px #3b302b0d;
  transform:rotate(1deg);
  border-radius:6px;
}
.course figure img {
  width:100%;
  height:auto;
}
.course figcaption {
  text-align:center;
  font-size:10px;
  color:var(--muted);
  margin-top:8px;
}
.course-button {
  display:flex;
  align-items:center;
  justify-content:space-between;
  gap:20px;
  background:#344a63;
  border-radius:6px;
  color:#fff;
  padding:15px 20px;
  font-size:14px;
  font-weight:700;
  max-width:350px;
  margin-top:23px;
}
.site-footer {
  padding-top:33px;
}
.footer-inner {
  display:flex;
  justify-content:space-between;
  align-items:center;
  gap:25px;
  padding-bottom:30px;
}
.footer-inner>div {
  font-size:12px;
}
.contact-link {
  color:#405e7d;
  font-weight:700;
  font-size:13px;
}
.copyright {
  text-align:center;
  font-size:12px;
  color:var(--muted);
  padding:15px 20px;
  border-top:1px solid var(--line);
}
.page-top {
  position:fixed;
  bottom:22px;
  right:22px;
  background:#fff;
  color:var(--red);
  border:1px solid #dbc7b6;
  border-radius:50%;
  width:43px;
  height:43px;
  display:grid;
  place-items:center;
  box-shadow:0 2px 7px #3b302b12;
  z-index:5;
}
@media(min-width:1500px) {
  .hero {
    background-size:100% auto;
  }
}
@media(max-width:900px) {
  .container {
    width:calc(100% - 40px);
  }
  .grade-grid {
    gap:20px;
  }
  .grade-heading,.grade-content {
    padding:22px;
  }
  .resource-heading {
    gap:8px;
    font-size:15px;
  }
  .steps {
    gap:18px;
  }
  .steps li {
    gap:9px;
  }
  .steps h3 {
    font-size:14px;
  }
  .course-inner {
    gap:30px;
  }
  .hero-inner {
    padding-top:64px;
  }
}
@media(max-width:700px) {
  .mobile-only {
    display:block;
  }
  .header-inner {
    padding:18px 20px;
    gap:16px;
  }
  .logo {
    width:178px;
  }
  .header-inner nav {
    gap:17px;
    font-size:12px;
  }
  .header-inner nav a:last-child {
    display:none;
  }
  .hero {
    background-image:url(../img/mv-bg-sp2.jpg);
    background-size:100% 100%;
  }
  .hero-inner {
    padding:72px 20px 105px;
  }
  .hero-eyebrow {
    font-size:12px;
    letter-spacing:.03em;
  }
  .edition {
    margin-top:12px;
    font-size:20px;
  }
  .edition strong {
    font-size:53px;
  }
  .edition>span {
    padding:15px 9px;
    font-size:14px;
    margin-right:8px;
  }
  .hero-subtitle {
    font-size:28px;
    letter-spacing:.03em;
    margin:7px 0 17px;
  }
  .hero-title {
    gap:10px;
  }
  .hero-title>span {
    width:70px;
    height:70px;
    font-size:43px;
  }
  .hero-message {
    font-size:22px;
    line-height:1.6;
    margin-top:24px;
    letter-spacing:.03em;
  }
  .hero-description {
    font-size:12px;
    line-height:1.9;
    margin-top:14px;
    margin-bottom:20px;
  }
  .hero-actions {
    gap:10px;
  }
  .grade-button {
    width:165px;
    padding:10px 13px;
    font-size:12px;
  }
  .grade-button strong {
    font-size:22px;
    margin-left:3px;
  }
  .hero-note {
    font-size:10px;
  }
  .intro {
    font-size:13px;
    padding-top:30px;
    padding-bottom:30px;
    text-align:left;
  }
  .intro br {
    display:none;
  }
  .share {
    margin-top:18px;
  }
  .section-heading h2 {
    font-size:23px;
  }
  .section-heading {
    margin-bottom:23px;
  }
  .eyebrow {
    font-size:10px;
  }
  .guide {
    padding-top:30px;
    padding-bottom:35px;
  }
  .steps {
    grid-template-columns:1fr;
    gap:21px;
  }
  .steps li {
    gap:16px;
    align-items:center;
  }
  .step-number {
    font-size:32px;
  }
  .steps h3 {
    font-size:15px;
    margin-bottom:3px;
  }
  .steps p {
    font-size:12px;
  }
  .materials {
    padding:36px 0;
  }
  .javascript-note {
    text-align:left;
    font-size:12px;
    padding:12px 15px;
  }
  .grade-grid {
    grid-template-columns:1fr;
    gap:28px;
  }
  .grade-heading {
    padding:20px 24px;
  }
  .grade-content {
    padding:24px;
  }
  .grade-heading h3 {
    font-size:25px;
  }
  .grade-heading h3 strong {
    font-size:47px;
  }
  .resource-heading {
    font-size:16px;
    gap:10px;
  }
  .download-button {
    padding:13px 17px;
  }
  .download-button strong {
    font-size:17px;
  }
  .video-cover strong {
    font-size:14px;
  }
  .cbt-link {
    font-size:15px;
    padding:15px 18px;
    margin-top:25px;
  }
  .cbt-link small {
    font-size:10px;
  }
  .notes {
    padding-top:32px;
    padding-bottom:35px;
  }
  .notes h2 {
    font-size:17px;
  }
  .notes ul {
    font-size:12px;
  }
  .course {
    padding:32px 0;
  }
  .course-inner {
    grid-template-columns:1fr;
    gap:30px;
  }
  .course h2 {
    font-size:25px;
  }
  .course-copy>p:not(.eyebrow) {
    font-size:12px;
  }
  .course-copy>p br {
    display:none;
  }
  .course figure {
    max-width:420px;
    margin:auto;
  }
  .course-button {
    font-size:13px;
    max-width:none;
  }
  .footer-inner {
    flex-direction:column;
    text-align:center;
    gap:20px;
  }
  .site-footer {
    padding-top:27px;
  }
  .page-top {
    right:12px;
    bottom:12px;
    width:38px;
    height:38px;
  }
}
@media(max-width:370px) {
  .container {
    width:calc(100% - 28px);
  }
  .header-inner {
    padding:16px 14px;
  }
  .logo {
    width:158px;
  }
  .hero-inner {
    padding-inline:14px;
  }
  .hero-title {
    gap:7px;
  }
  .hero-title>span {
    width:62px;
    height:62px;
    font-size:39px;
  }
  .hero-subtitle {
    font-size:25px;
  }
  .hero-actions {
    gap:8px;
  }
  .grade-button {
    padding:9px 10px;
    width:145px;
  }
  .grade-content {
    padding:20px;
  }
  .resource-heading {
    font-size:14px;
  }
  .mobile-only {
    display:block;
  }
  .hero-note {
    font-size:9px;
  }
}
@media(prefers-reduced-motion:reduce) {
  html {
    scroll-behavior:auto;
  }
  * {
    transition:none!important;
  }
}
@media print {
  .site-header nav,.hero-actions,.share,.timer-link,.book-link,.cbt-link,.course,.site-footer,.page-top {
    display:none;
  }
  .hero {
    background:none;
  }
  .hero-inner {
    padding:20px;
  }
  .hero-title>span {
    background:none;
    color:var(--red);
    box-shadow:none;
  }
  .grade-grid {
    display:block;
  }
  .grade-card {
    break-inside:avoid;
    margin-bottom:20px;
  }
  .container {
    width:100%;
  }
}