/* custom properties */
:root {
  --color-primary: #e61975;
  --color-secondary: #263e71;
  --color-link: #263e71;
  --color-hover: #e61975;
  --color-white: #fff;
  --color-black: #000;
  --color-gray: #666;
  --color-lightgray: #999;
  --color-maintext: #263e71;
  --color-subtext: #ff9bd2;
  --color-bg01: #fff1f9;
  --color-bg02: #263e71;
  --color-bg03: #ff9bd2;
  --font-family-sans-serif: "Noto Sans JP", sans-serif;
  --font-family-font-awesome: "Font Awesome 6 Free"; }

html {
  font-size: 62.5%; }

body {
  margin: 0;
  font-family: var(--font-family-sans-serif);
  font-size: clamp( 1.6rem, calc(1.6rem + (2.3rem - 1.6rem) * ((100vw - 375px) / (1200px - 375px))), 2.3rem );
  font-weight: 400;
  letter-spacing: 0.05em;
  font-feature-settings: "palt";
  line-height: 1.6;
  color: var(--color-maintext);
  background-image: linear-gradient(0deg, #ffb7d7, #abc6ff 50%, #ffb7d7); }
  body.no-scroll {
    overflow: hidden; }

img {
  width: 100%;
  height: auto;
  vertical-align: middle;
  border-style: none; }

a {
  color: var(--color-link);
  text-decoration: none;
  transition: 0.3s; }
  a:visited {
    color: var(--color-link); }
  a:hover {
    color: var(--color-hover);
    text-decoration: none; }

.wrapper {
  width: 100%; }

#contents {
  width: 100%;
  max-width: 540px;
  margin: 0 auto;
  margin-top: 60px;
  background: var(--color-bg01); }

.side_logo {
  display: none;
  width: 100%;
  max-width: 30rem; }
  .side_logo img {
    width: 100%;
    height: auto; }

.side_menu {
  display: none; }

.header {
  position: fixed;
  top: 0;
  left: 50%;
  transform: translateX(-50%);
  width: 100%;
  max-width: 540px;
  height: 60px;
  z-index: 1000;
  color: var(--color-white);
  background: var(--color-primary); }
  .header_inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    height: 100%;
    padding: 0 1.5rem; }

.logo img {
  height: 30px; }

.hamburger {
  width: 30px;
  height: 24px;
  position: relative;
  border: none;
  appearance: none;
  background: none;
  cursor: pointer; }
  .hamburger span {
    position: absolute;
    left: 0;
    width: 100%;
    height: 2px;
    background: var(--color-white);
    transition: 0.3s; }
  .hamburger span:nth-child(1) {
    top: 0; }
  .hamburger span:nth-child(2) {
    top: 10px; }
  .hamburger span:nth-child(3) {
    bottom: 0; }
  .hamburger.active span:nth-child(1) {
    transform: rotate(45deg);
    top: 10px; }
  .hamburger.active span:nth-child(2) {
    opacity: 0; }
  .hamburger.active span:nth-child(3) {
    transform: rotate(-45deg);
    bottom: 12px; }

.drawer {
  position: fixed;
  top: 0;
  right: 0;
  width: 80%;
  max-width: 300px;
  height: 100%;
  background: var(--color-white);
  z-index: 999;
  padding-top: 60px;
  transform: translateX(100%);
  transition: transform 0.4s ease; }
  .drawer.open {
    transform: translateX(0); }
  .drawer li {
    border-bottom: 1px solid var(--color-bg01); }
  .drawer a {
    display: block;
    padding: 15px;
    color: var(--color-primary);
    font-weight: 700; }
    .drawer a:hover {
      background: var(--color-bg01); }

.overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(0, 0, 0, 0.5);
  opacity: 0;
  visibility: hidden;
  transition: 0.3s;
  z-index: 998; }
  .overlay.show {
    opacity: 1;
    visibility: visible; }

.footer {
  padding: 1.5rem 1.0rem;
  color: var(--color-white);
  background: var(--color-primary); }
  .footer .copyright {
    font-size: 1.2rem;
    text-align: center; }

.to_top {
  position: fixed;
  right: 2.0rem;
  bottom: 2.0rem;
  z-index: 900;
  width: 5.0rem;
  height: 5.0rem;
  opacity: 0;
  visibility: hidden;
  transform: translateY(10px) scale(1);
  transition: opacity 0.3s, transform 0.3s, box-shadow 0.3s;
  border: none;
  background: none;
  padding: 0;
  appearance: none; }
  .to_top img {
    width: 100%;
    height: auto; }
  .to_top.show {
    opacity: 1;
    visibility: visible;
    transform: translateY(0) scale(1); }
  @media screen and (min-width: 768px) {
    .to_top:hover {
      transform: translateY(-4px) scale(1.05);
      filter: drop-shadow(0 6px 12px rgba(0, 0, 0, 0.15)); } }

#contents #sec_topics .topics_list {
  display: block;
  margin: 0 auto 3.0rem;
  padding: 0 2.0rem; }
  #contents #sec_topics .topics_list > li {
    display: block;
    margin: 0 0 2.0rem; }
    #contents #sec_topics .topics_list > li .topics_date {
      display: inline-block;
      padding: 0.6em 1em;
      color: var(--color-subtext);
      font-weight: 600;
      line-height: 1.0;
      background: var(--color-secondary); }
    #contents #sec_topics .topics_list > li .topics_title {
      padding: 1.5rem;
      background: var(--color-white);
      border: 2px solid var(--color-secondary); }

@media screen and (min-width: 1200px) {
  .wrapper {
    display: grid;
    grid-template-columns: 1fr 540px 1fr; }

  #contents {
    grid-column: 2;
    margin-top: 0; }

  .side_logo {
    display: block;
    position: fixed;
    top: 50%;
    left: calc(50% - (540px / 2) - 32rem);
    transform: translateY(-50%); }

  .side_menu {
    display: block;
    position: fixed;
    top: 50%;
    left: calc(50% + (540px / 2) + 4rem);
    transform: translateY(-50%); }
    .side_menu > ul {
      display: flex;
      flex-direction: column;
      row-gap: 1rem; }
      .side_menu > ul > li a {
        display: block;
        color: var(--color-primary);
        font-weight: 700;
        text-align: center;
        padding: 1.5rem 2.0rem;
        background: var(--color-white);
        border-radius: 10px; }
        .side_menu > ul > li a:hover {
          color: var(--color-white);
          text-decoration: none;
          background: var(--color-primary); }

  .header {
    display: none; } }