/* T-1000 Move List CSS */
:root {
    --key-color: #7b7185;
    --sub-color-1: #464555;
    --sub-color-2: #aaa8cc;
    --text-color-dark: #070707;
    --text-color-light: #ffffff;
    --section-bg-color: #fdfaf9;
    --base-bg-color: #333645;
    --dark-accent: #000000;
    --light-accent: #ffffff;
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}
main {
    max-width: 800px;
    margin: 0 auto;
    padding: 2px;
}
body {
    font-family: 'Arial', 'Helvetica', sans-serif;
    background-color: var(--base-bg-color);
    color: var(--text-color-light);
    line-height: 1.6;
    padding-bottom: 50px;
}

header {
    background-color: var(--sub-color-1);
    padding: 30px 20px;
    text-align: center;
    position: relative;
    box-shadow: 0 4px 10px rgba(0, 0, 0, 0.5);
}


.liquid-metal-bar {
    height: 8px;
    background: linear-gradient(90deg, var(--sub-color-1), var(--key-color), var(--sub-color-2), var(--key-color), var(--sub-color-1));
    margin-top: 10px;
    animation: shimmer 3s infinite linear;
}

@keyframes shimmer {
    0% {
        background-position: 0% 50%;
    }
    50% {
        background-position: 100% 50%;
    }
    100% {
        background-position: 0% 50%;
    }
}

.table-of-contents {
    background-color: var(--section-bg-color);
    color: var(--text-color-dark);
    padding: 30px;
    margin: 30px;
    border-radius: 10px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
}

.table-of-contents h2 {
    text-align: center;
    font-size: 1.8rem;
    margin-bottom: 20px;
    color: var(--sub-color-1);
    border-bottom: 3px solid var(--key-color);
    padding-bottom: 10px;
}

.table-of-contents h3 {
    color: var(--key-color);
    font-size: 1.4rem;
    margin: 15px 0 10px;
    padding-bottom: 5px;
    border-bottom: 2px solid var(--sub-color-2);
}

.toc-container {
    display: flex;
    flex-wrap: wrap;
    justify-content: space-between;
}

.toc-column {
    flex: 1;
    min-width: 220px;
    padding: 0 15px;
}

.toc-column ul {
    list-style-type: none;
}

.toc-column li {
    margin-bottom: 8px;
}

.toc-column a {
    color: var(--text-color-dark);
    text-decoration: none;
    transition: color 0.3s, transform 0.3s;
    display: inline-block;
}

.toc-column a:hover {
    color: var(--key-color);
    transform: translateX(5px);
}

main {
    padding: 20px;
}

.move-category {
    margin-bottom: 50px;
}

.move-category h2 {
    font-size: 2rem;
    background-color: var(--key-color);
    color: var(--text-color-light);
    padding: 15px 20px;
    border-radius: 8px 8px 0 0;
    text-align: center;
    margin-bottom: 20px;
    letter-spacing: 1px;
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.2);
    text-shadow: 1px 1px 3px var(--dark-accent);
}

.move-item {
    background-color: var(--section-bg-color);
    margin-bottom: 30px;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    transition: transform 0.3s;
}

.move-item:hover {
    transform: translateY(-5px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
}

.move-item h3 {
    background-color: var(--sub-color-1);
    color: var(--text-color-light);
    padding: 15px 20px;
    font-size: 1.5rem;
    margin: 0;
    position: relative;
}

.move-item .jp-name {
    font-size: 1rem;
    margin-left: 10px;
    color: var(--sub-color-2);
}

figure {
    width: 100%;
    margin: 0;
    position: relative;
    overflow: hidden;
}

.move-image {
    width: 100%;
    height: auto;
    display: block;
    transition: transform 0.5s;
}

.move-item:hover .move-image {
    transform: scale(1.03);
}

figcaption {
    background-color: rgba(0, 0, 0, 0.7);
    color: var(--text-color-light);
    padding: 8px 15px;
    font-size: 0.9rem;
    text-align: center;
}

.move-details {
    padding: 20px;
    color: var(--text-color-dark);
}

.move-detail {
    margin-bottom: 10px;
    display: flex;
}

.move-detail span:first-child {
    font-weight: bold;
    width: 120px;
    color: var(--sub-color-1);
}

.move-description {
    margin-top: 15px;
    padding-top: 15px;
    border-top: 1px solid var(--key-color);
}

.move-description p {
    font-size: 1.1rem;
}

/* ナビゲーション用のスタイル */
.back-to-top {
    position: fixed;
    bottom: 20px;
    right: 20px;
    background-color: var(--key-color);
    color: var(--text-color-light);
    padding: 10px 15px;
    border-radius: 50%;
    text-decoration: none;
    font-size: 1.2rem;
    box-shadow: 0 2px 5px rgba(0, 0, 0, 0.3);
    transition: background-color 0.3s, transform 0.3s;
    z-index: 100;
}

.back-to-top:hover {
    background-color: var(--sub-color-2);
    transform: translateY(-3px);
}

/* レスポンシブデザイン */
@media (max-width: 1200px) {
    .toc-column {
        min-width: 180px;
    }
}

@media (max-width: 992px) {
    .toc-container {
        flex-direction: column;
    }

    .toc-column {
        width: 100%;
        margin-bottom: 20px;
    }

    header h1 {
        font-size: 2rem;
    }
}

@media (max-width: 768px) {
    .table-of-contents,
    main {
        padding: 15px;
        margin: 15px;
    }

    .move-item h3 {
        font-size: 1.3rem;
    }

    .move-detail span:first-child {
        width: 100px;
    }

    .move-description p {
        font-size: 1rem;
    }
}

@media (max-width: 576px) {
    header h1 {
        font-size: 1.5rem;
    }

    .table-of-contents h2 {
        font-size: 1.5rem;
    }

    .move-category h2 {
        font-size: 1.5rem;
    }

    .move-item h3 {
        font-size: 1.1rem;
    }
}

/* T-1000 Footer Styles */
footer.copy {
    background-color: var(--sub-color-1);
    color: var(--text-color-light);
    padding: 30px 20px;
    margin-top: 40px;
    border-top: 8px solid;
    border-image: linear-gradient(90deg, var(--sub-color-1), var(--key-color), var(--sub-color-2), var(--key-color), var(--sub-color-1)) 1;
    position: relative;
    box-shadow: 0 -5px 15px rgba(0, 0, 0, 0.3);
}

footer.copy::before {
    content: "";
    position: absolute;
    top: -3px;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--light-accent), transparent);
    animation: metalShimmer 3s infinite linear;
}

@keyframes metalShimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

.contact-info, .usage-terms, .copyright {
    margin: 20px 0;
    padding: 15px;
    background-color: rgba(0, 0, 0, 0.2);
    border-radius: 8px;
    border-left: 4px solid var(--key-color);
    transition: transform 0.3s, box-shadow 0.3s;
}

.contact-info:hover, .usage-terms:hover, .copyright:hover {
    transform: translateY(-3px);
    box-shadow: 0 5px 10px rgba(0, 0, 0, 0.3);
}

.contact-info a, .copyright a {
    color: var(--sub-color-2);
    text-decoration: none;
    transition: color 0.3s;
    display: inline-flex;
    align-items: center;
}

.contact-info a:hover, .copyright a:hover {
    color: var(--light-accent);
    text-decoration: underline;
}

.contact-info img, .copyright img {
    margin-right: 8px;
    display: inline-block;
    vertical-align: middle;
}

.usage-terms p {
    margin: 8px 0;
    line-height: 1.5;
    position: relative;
    padding-left: 5px;
}

.copyright {
    text-align: center;
    padding: 15px;
    font-weight: bold;
    display: flex;
    justify-content: center;
    align-items: center;
    background: linear-gradient(135deg, var(--sub-color-1), var(--dark-accent));
}

.push0 {
    display: inline-flex;
    align-items: center;
    margin-right: 10px;
    padding: 5px 10px;
    background-color: rgba(123, 113, 133, 0.2);
    border-radius: 5px;
    transition: background-color 0.3s;
}

.push0:hover {
    background-color: rgba(123, 113, 133, 0.4);
}

/* メタリック効果のために、フッターにホバーすると光沢が変わる */
footer.copy:hover::before {
    animation-duration: 1.5s;
}
/* 更新時間とSNSボタン用スタイル */
.time {
    font-size: 0.9rem;
    color: var(--sub-color-2);
    background-color: rgba(70, 69, 85, 0.7);
    display: inline-block;
    padding: 8px 15px;
    margin: 20px 0;
    border-radius: 5px;
    border-left: 3px solid var(--key-color);
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.2);
    position: relative;
    overflow: hidden;
}

.time::after {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg,
                               transparent 0%,
                               rgba(255, 255, 255, 0.1) 25%,
                               transparent 50%);
    transform: translateX(-100%);
    animation: timeShimmer 3s infinite;
}

@keyframes timeShimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

.time time {
    font-weight: bold;
    margin-right: 5px;
    color: var(--text-color-light);
}

/* SNSボタンコンテナスタイル */
.share-buttons {
    display: inline-block;
    margin: 10px 10px 10px 0;
    vertical-align: middle;
}

/* Facebookコンテナスタイル */
.fb-share-button {
    display: inline-block;
    margin: 10px 0;
    vertical-align: middle;
}

/* SNSボタン共通コンテナ */
.share-container {
    background-color: var(--section-bg-color);
    padding: 15px;
    border-radius: 8px;
    margin: 20px 0;
    display: flex;
    align-items: center;
    flex-wrap: wrap;
    box-shadow: 0 3px 6px rgba(0, 0, 0, 0.2);
    border-top: 3px solid var(--key-color);
}

.share-container::before {
    content: "シェアする:";
    margin-right: 15px;
    font-weight: bold;
    color: var(--sub-color-1);
}

/* レスポンシブデザイン */
@media (max-width: 576px) {
    .time {
        font-size: 0.8rem;
        padding: 6px 10px;
    }

    .share-container {
        padding: 10px;
    }

    .share-container::before {
        display: block;
        margin-bottom: 10px;
        width: 100%;
    }
}

/* メニュー、パンくず、H1スタイル */

/* SVGメニュースタイル */
svg#_モータルコンバット1メニュー {
    width: 100%;
    height: auto;
    max-width: 800px;
    margin: 0 auto 20px;
    display: block;
    filter: drop-shadow(0 4px 6px rgba(0, 0, 0, 0.3));
}

svg#_モータルコンバット1メニュー image {
    transition: transform 0.3s, filter 0.3s;
}

svg#_モータルコンバット1メニュー a:hover image {
    transform: scale(1.05);
    filter: brightness(1.2);
}

/* パンくずリストスタイル */
.breadcrumb-nav {
    padding: 10px 15px;
    margin-bottom: 25px;
    background: linear-gradient(90deg, var(--sub-color-1), var(--base-bg-color));
    border-radius: 5px;
    box-shadow: 0 3px 5px rgba(0, 0, 0, 0.2);
    position: relative;
    border-left: 4px solid var(--key-color);
}

.breadcrumb-nav::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 1px;
    background: linear-gradient(90deg, var(--key-color), transparent);
}

.breadcrumb {
    list-style: none;
    display: flex;
    flex-wrap: wrap;
    padding: 0;
    margin: 0;
}

.breadcrumb-item {
    display: flex;
    align-items: center;
    color: var(--sub-color-2);
    font-size: 0.9rem;
}

.breadcrumb-item:not(:last-child)::after {
    content: "›";
    margin: 0 8px;
    color: var(--sub-color-2);
    font-weight: bold;
}

.breadcrumb-link {
    color: var(--sub-color-2);
    text-decoration: none;
    transition: color 0.3s, text-shadow 0.3s;
    position: relative;
}

.breadcrumb-link:hover {
    color: var(--light-accent);
    text-shadow: 0 0 5px rgba(170, 168, 204, 0.5);
}

.breadcrumb-link::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: var(--light-accent);
    transition: width 0.3s;
}

.breadcrumb-link:hover::after {
    width: 100%;
}

.current-page {
    font-weight: bold;
    color: var(--text-color-light);
}

/* H1タイトルスタイル */
h1 {
    font-size: 2rem;
    font-weight: 700;
    color: var(--text-color-light);
    text-align: center;
    margin: 30px 0;
    padding: 15px 20px;
    background: linear-gradient(135deg, var(--sub-color-1), var(--base-bg-color));
    border-radius: 8px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    position: relative;
    overflow: hidden;
    line-height: 1.4;
    letter-spacing: 1px;
    border-bottom: 3px solid var(--key-color);
}

h1::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg,
                   transparent 0%,
                   rgba(123, 113, 133, 0.2) 25%,
                   transparent 50%);
    animation: titleShimmer 5s infinite linear;
    z-index: 1;
}

@keyframes titleShimmer {
    0% {
        transform: translateX(-100%);
    }
    100% {
        transform: translateX(100%);
    }
}

h1::after {
    content: "";
    position: absolute;
    bottom: 0;
    left: 0;
    width: 100%;
    height: 3px;
    background: linear-gradient(90deg, transparent, var(--key-color), transparent);
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    h1 {
        font-size: 1.5rem;
        padding: 12px 15px;
    }

    .breadcrumb-item {
        font-size: 0.8rem;
    }
}

@media (max-width: 576px) {
    h1 {
        font-size: 1.3rem;
        padding: 10px;
    }

    svg#_モータルコンバット1メニュー {
        max-width: 100%;
    }

    .breadcrumb-nav {
        padding: 8px 10px;
    }

    .breadcrumb-item:not(:last-child)::after {
        margin: 0 5px;
    }
}

/* T-1000 おすすめセクションスタイル */
#recommendations {
    margin: 40px 0;
    padding: 25px;
    background: linear-gradient(135deg, var(--sub-color-1), var(--base-bg-color));
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.4);
    position: relative;
    border-left: 5px solid var(--key-color);
    overflow: hidden;
}

#recommendations::before {
    content: "おすすめ記事";
    display: block;
    margin-bottom: 20px;
    font-size: 1.5rem;
    font-weight: bold;
    color: var(--text-color-light);
    text-align: center;
    padding-bottom: 10px;
    border-bottom: 2px solid var(--key-color);
    position: relative;
}

#recommendations::after {
    content: "";
    position: absolute;
    top: 0;
    left: -150%;
    width: 200%;
    height: 100%;
    background: linear-gradient(90deg,
                transparent 0%,
                rgba(123, 113, 133, 0.1) 25%,
                rgba(170, 168, 204, 0.15) 50%,
                rgba(123, 113, 133, 0.1) 75%,
                transparent 100%);
    transform: skewX(-30deg);
    animation: liquidMetal 8s infinite linear;
    pointer-events: none;
}

@keyframes liquidMetal {
    0% {
        left: -150%;
    }
    100% {
        left: 100%;
    }
}

#recommendations a.push0 {
    display: flex;
    align-items: center;
    background-color: rgba(0, 0, 0, 0.3);
    border-radius: 8px;
    padding: 12px;
    margin-bottom: 15px;
    text-decoration: none;
    color: var(--text-color-light);
    transition: transform 0.3s, box-shadow 0.3s, background-color 0.3s;
    border: 1px solid rgba(123, 113, 133, 0.3);
    position: relative;
    overflow: hidden;
}

#recommendations a.push0:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.3);
    background-color: rgba(70, 69, 85, 0.6);
    border-color: var(--key-color);
}

#recommendations a.push0::before {
    content: "";
    position: absolute;
    top: -50%;
    left: -50%;
    width: 200%;
    height: 200%;
    background: radial-gradient(circle, rgba(170, 168, 204, 0.1) 0%, transparent 70%);
    opacity: 0;
    transition: opacity 0.5s;
    pointer-events: none;
}

#recommendations a.push0:hover::before {
    opacity: 1;
    animation: pulseLight 2s infinite;
}

@keyframes pulseLight {
    0%, 100% {
        transform: scale(1);
        opacity: 0.3;
    }
    50% {
        transform: scale(1.05);
        opacity: 0.5;
    }
}

#recommendations img.sneak {
    width: 120px;
    height: 55px;
    object-fit: cover;
    border-radius: 5px;
    margin-right: 15px;
    box-shadow: 0 3px 5px rgba(0, 0, 0, 0.2);
    border: 1px solid var(--key-color);
    transition: transform 0.3s;
}

#recommendations a.push0:hover img.sneak {
    transform: scale(1.05);
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    #recommendations {
        padding: 20px 15px;
    }

    #recommendations::before {
        font-size: 1.3rem;
    }

    #recommendations a.push0 {
        flex-direction: row;
        padding: 10px;
    }

    #recommendations img.sneak {
        width: 100px;
        height: 46px;
        margin-right: 10px;
    }
}

@media (max-width: 576px) {
    #recommendations {
        padding: 15px 10px;
    }

    #recommendations::before {
        font-size: 1.2rem;
        margin-bottom: 15px;
    }

    #recommendations a.push0 {
        font-size: 0.9rem;
    }

    #recommendations img.sneak {
        width: 80px;
        height: 37px;
    }
}
/* T-1000紹介セクションスタイル */
.t1000-intro {
    margin: 35px 0;
    padding: 25px;
    background: linear-gradient(135deg, rgba(70, 69, 85, 0.9), rgba(51, 54, 69, 0.95));
    border-radius: 10px;
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.4);
    position: relative;
    border-left: 5px solid var(--key-color);
    overflow: hidden;
    color: var(--text-color-light);
    line-height: 1.7;
}

.t1000-intro::before {
    content: "";
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: url('image/t1000-bg-pattern.webp') repeat;
    opacity: 0.05;
    z-index: -1;
    pointer-events: none;
}

.t1000-intro h2 {
    margin-top: 0;
    margin-bottom: 20px;
    font-size: 1.8rem;
    color: var(--sub-color-2);
    text-align: center;
    border-bottom: 2px solid var(--key-color);
    padding-bottom: 10px;
    position: relative;
}

.t1000-intro h2::after {
    content: "";
    position: absolute;
    bottom: -2px;
    left: 50%;
    transform: translateX(-50%);
    width: 50%;
    height: 2px;
    background: linear-gradient(90deg, transparent, var(--key-color), transparent);
}

.t1000-intro p {
    margin-bottom: 15px;
    text-align: justify;
    position: relative;
    z-index: 1;
}

.t1000-intro p:last-child {
    margin-bottom: 0;
    font-weight: bold;
    color: var(--sub-color-2);
}

.t1000-intro::after {
    content: "";
    position: absolute;
    top: 0;
    left: -100%;
    width: 200%;
    height: 200%;
    background: radial-gradient(ellipse at center, rgba(170, 168, 204, 0.1) 0%, transparent 70%);
    opacity: 0.5;
    transform: skewX(-45deg);
    animation: t1000Shimmer 10s infinite linear;
    pointer-events: none;
}

@keyframes t1000Shimmer {
    0% {
        left: -100%;
        top: -100%;
    }
    100% {
        left: 100%;
        top: 100%;
    }
}

/* 強調テキスト */
.t1000-intro strong {
    color: var(--sub-color-2);
    font-weight: bold;
}

/* レスポンシブデザイン */
@media (max-width: 768px) {
    .t1000-intro {
        padding: 20px;
    }

    .t1000-intro h2 {
        font-size: 1.5rem;
    }
}

@media (max-width: 576px) {
    .t1000-intro {
        padding: 15px;
    }

    .t1000-intro h2 {
        font-size: 1.3rem;
    }

    .t1000-intro p {
        font-size: 0.95rem;
    }
}
/* モバイル表示最適化のためのCSS */

/* 基本的な余白調整 */
@media (max-width: 768px) {
  body {
    padding-left: 10px !important;
    padding-right: 10px !important;
  }

  main,
  header,
  .table-of-contents,
  .move-category,
  .t1000-intro,
  #recommendations,
  footer.copy {
    padding-left: 12px !important;
    padding-right: 12px !important;
    margin-left: 5px !important;
    margin-right: 5px !important;
  }

  .breadcrumb-nav {
    padding-left: 8px !important;
    padding-right: 8px !important;
  }
}

/* さらに小さい画面での調整 */
@media (max-width: 576px) {
  body {
    padding-left: 5px !important;
    padding-right: 5px !important;
  }

  main,
  header,
  .table-of-contents,
  .move-category,
  .t1000-intro,
  #recommendations,
  footer.copy {
    padding-left: 8px !important;
    padding-right: 8px !important;
    margin-left: 2px !important;
    margin-right: 2px !important;
  }

  .breadcrumb-nav {
    padding-left: 5px !important;
    padding-right: 5px !important;
  }

  /* 技表アイテムの余白調整 */
  .move-item {
    padding: 5px !important;
  }

  .move-details {
    padding: 10px !important;
  }

  /* 画像キャプションの余白調整 */
  figcaption {
    padding: 5px 8px !important;
  }

  /* メイン見出しの余白調整 */
  h1 {
    padding: 10px 8px !important;
    margin: 20px 0 !important;
  }

  /* 目次の間隔調整 */
  .toc-column {
    padding: 0 8px !important;
  }
}

/* 最小画面サイズでの極限調整 */
@media (max-width: 375px) {
  body {
    padding-left: 2px !important;
    padding-right: 2px !important;
  }

  main,
  header,
  .table-of-contents,
  .move-category,
  .t1000-intro,
  #recommendations,
  footer.copy {
    padding-left: 5px !important;
    padding-right: 5px !important;
    margin-left: 1px !important;
    margin-right: 1px !important;
  }

  /* コンテンツ最大幅の調整 */
  .move-image,
  figure img {
    width: 100% !important;
    max-width: 100% !important;
  }

  /* 文字サイズの微調整 */
  .move-description p {
    font-size: 0.9rem !important;
  }

  .move-detail span {
    font-size: 0.9rem !important;
  }
}

/* コンテンツ最大幅の調整（全モバイルサイズ） */
@media (max-width: 768px) {
  .move-image,
  figure img {
    width: 100% !important;
    height: auto !important;
    max-width: 100% !important;
  }

  /* コンテナ幅調整 */
  .container,
  .content-container,
  .main-content,
  body > div {
    width: 100% !important;
    max-width: 100% !important;
    padding-left: 0 !important;
    padding-right: 0 !important;
  }

  /* テーブルレイアウト調整 */
  table, tr, td {
    width: 100% !important;
    max-width: 100% !important;
  }
}
/* 目次に戻るボタンスタイル */
.back-to-toc {
    width: 100%;
    margin: 20px 0 10px;
    text-align: center;
}

.back-to-toc a {
    display: block;
    width: 100%;
    padding: 12px 20px;
    background: linear-gradient(to right, var(--sub-color-1), var(--key-color), var(--sub-color-1));
    color: var(--text-color-light);
    text-decoration: none;
    font-weight: bold;
    font-size: 1.1rem;
    border-radius: 5px;
    box-shadow: 0 4px 8px rgba(0, 0, 0, 0.3);
    transition: all 0.3s ease;
    position: relative;
    overflow: hidden;
    text-transform: uppercase;
    letter-spacing: 1px;
    border: 1px solid rgba(170, 168, 204, 0.3);
}

.back-to-toc a::before {
    content: "";
    position: absolute;
    top: 0;
    left: -100%;
    width: 100%;
    height: 100%;
    background: linear-gradient(90deg,
                transparent 0%,
                rgba(255, 255, 255, 0.2) 50%,
                transparent 100%);
    transition: left 0.7s ease;
}

.back-to-toc a:hover {
    transform: translateY(-3px);
    box-shadow: 0 6px 12px rgba(0, 0, 0, 0.4);
    background: linear-gradient(to right, var(--key-color), var(--sub-color-2), var(--key-color));
}

.back-to-toc a:hover::before {
    left: 100%;
}

.back-to-toc a::after {
    content: "↑";
    margin-left: 8px;
    font-size: 1.2rem;
    vertical-align: middle;
}

/* モバイル向け調整 */
@media (max-width: 768px) {
    .back-to-toc a {
        padding: 10px 15px;
        font-size: 1rem;
    }
}

@media (max-width: 576px) {
    .back-to-toc a {
        padding: 8px 10px;
        font-size: 0.9rem;
    }

    .back-to-toc a::after {
        font-size: 1rem;
    }
}