/* ==========================
   ベース設定
   ========================== */
*,
*::before,
*::after {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI",
                 "Yu Gothic", "YuGothic", "Meiryo", sans-serif;
    line-height: 1.7;
    color: #222;
    background-color: #f7f8fb;
}

.container {
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    padding: 0 16px;
}

h1, h2, h3, h4 {
    margin-top: 0;
    font-weight: 600;
}

a {
    color: #1f6feb;
    text-decoration: none;
}

a:hover {
    text-decoration: underline;
}

/* ==========================
   ヘッダー
   ========================== */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: linear-gradient(90deg, #ffffffcc, #eef3ffcc); /* ほんのり青いグラデーション */
    backdrop-filter: blur(6px);
    border-bottom: 1px solid #e0e3eb;
}

.header-inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    padding: 8px 0;
}

.site-title-block {
    display: flex;
    flex-direction: column;
}

.site-title {
    font-size: 1.4rem;
    margin-bottom: 2px;
}

.site-subtitle {
    margin: 0;
    font-size: 0.85rem;
    color: #444;
}

.site-nav {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.site-nav a {
    font-size: 0.9rem;
    padding: 4px 10px;
    border-radius: 999px;
    background-color: rgba(255, 255, 255, 0.9);
    border: 1px solid transparent;
    color: #222;
    transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

.site-nav a:hover {
    background-color: #1f6feb10;
    color: #1f6feb;
    border-color: #1f6feb40;
}

/* ==========================
   トップ画像スライド
   ========================== */
.top-slider {
    width: 100%;
    background-color: #fff;
}

.top-slider-inner {
    position: relative;
    width: 100%;
    max-width: 1100px;
    margin: 0 auto;
    height: 520px;
    overflow: hidden;
    user-select: none;
}

.top-slider-track {
    width: 100%;
    height: 100%;
    display: flex;
    transition: transform 0.8s ease-out;
}

.top-slide {
    flex: 0 0 100%;
    height: 100%;
}

.top-slide img {
    width: 100%;
    height: 100%;
    object-fit: cover;
}

.top-slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    border: none;
    background-color: rgba(255, 255, 255, 0.6);
    color: #333;
    width: 36px;
    height: 36px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    transition: background-color 0.2s, transform 0.2s;
}

.top-slider-btn.prev {
    left: 12px;
}

.top-slider-btn.next {
    right: 12px;
}

.top-slider-btn:hover {
    background-color: rgba(255, 255, 255, 0.9);
    transform: translateY(-50%) scale(1.05);
}

.slider-dots {
    position: absolute;
    bottom: 10px;
    left: 50%;
    transform: translateX(-50%);
    display: flex;
    gap: 6px;
}

.slider-dot {
    width: 10px;
    height: 10px;
    border-radius: 50%;
    background-color: #ddd;
    cursor: pointer;
}

.slider-dot.active {
    background-color: #333;
}

/* ==========================
   HERO
   ========================== */
.hero {
    padding: 40px 0 40px;
}

.hero-inner {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
    align-items: stretch;
}

.hero-text {
    flex: 2 1 320px;
}

.hero-label {
    display: inline-block;
    font-size: 0.85rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #1f6feb;
    margin-bottom: 8px;
}

.hero h2 {
    font-size: 1.8rem;
    margin-bottom: 12px;
}

.hero-lead {
    margin-top: 0;
    margin-bottom: 18px;
    color: #444;
}

.hero-links {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
}

.hero-card {
    flex: 1.4 1 260px;
}

.hero-card-inner {
    background-color: #ffffff;
    border-radius: 16px;
    padding: 16px 18px;
    border: 1px solid #e0e3eb;
    box-shadow: 0 10px 25px rgba(15, 23, 42, 0.08);
}

.hero-card-title {
    font-size: 0.9rem;
    font-weight: 600;
    color: #555;
    margin-top: 8px;
    margin-bottom: 4px;
}

.hero-card-text {
    margin-top: 0;
    margin-bottom: 8px;
}

.hero-card-list {
    margin: 0;
    padding-left: 18px;
    font-size: 0.9rem;
}

/* ボタン */
.btn {
    display: inline-block;
    padding: 8px 18px;
    border-radius: 999px;
    border: 1px solid transparent;
    font-size: 0.95rem;
    cursor: pointer;
    transition: background-color 0.15s, color 0.15s, border-color 0.15s;
    text-decoration: none;
}

.btn.primary {
    background-color: #1f6feb;
    color: #ffffff;
    border-color: #1f6feb;
}

.btn.primary:hover {
    background-color: #1552b3;
    border-color: #1552b3;
}

.btn.ghost {
    background-color: transparent;
    color: #1f6feb;
    border-color: #1f6feb33;
}

.btn.ghost:hover {
    background-color: #1f6feb10;
    border-color: #1f6feb66;
}

/* ==========================
   セクション共通
   ========================== */
.section {
    padding: 40px 0;
}

.section-alt {
    background-color: #ffffff;
}

.section-title {
    font-size: 1.5rem;
    margin-bottom: 12px;
    border-left: 4px solid #1f6feb;
    padding-left: 10px;
}

/* 2カラム */
.two-column {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
}

.column {
    flex: 1 1 260px;
}

/* ==========================
   NEWS
   ========================== */
.news-list {
    list-style: none;
    padding-left: 0;
    margin: 0;
}

.news-list li {
    padding: 8px 0;
    border-bottom: 1px solid #e0e3eb;
    font-size: 0.95rem;
}

.news-date {
    font-weight: 600;
    color: #1f6feb;
    margin-right: 12px;
}

/* ==========================
   プロフィール
   ========================== */
.profile-photo {
    width: 260px;
    height: 260px;
    max-width: 100%;
    object-fit: cover;
    border-radius: 12px;
    display: block;
    margin: 0 auto 16px;
    border: 3px solid #e0e3eb;
    box-shadow: 0 4px 16px rgba(0, 0, 0, 0.15);
}

.timeline {
    list-style: none;
    padding-left: 0;
    margin-top: 10px;
}

.timeline li {
    margin-bottom: 6px;
    font-size: 0.9rem;
}

.timeline .time {
    font-weight: 600;
    margin-right: 6px;
}

.tag-list {
    list-style: none;
    padding-left: 0;
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
    margin: 8px 0 16px;
}

.tag-list li {
    font-size: 0.85rem;
    padding: 4px 10px;
    border-radius: 999px;
    background-color: #e3ecff;
    color: #234;
}

.link-list {
    list-style: none;
    padding-left: 0;
}

.link-list li {
    margin-bottom: 4px;
    font-size: 0.9rem;
}

.tiny-note {
    font-size: 0.8rem;
    color: #666;
    margin-top: 4px;
}

/* ==========================
   研究テーマカード
   ========================== */
.card-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

.card {
    flex: 0 0 calc(33.333% - 20px);
    min-width: 260px;
    background-color: #ffffff;
    border-radius: 14px;
    padding: 16px 18px;
    border: 1px solid #e0e3eb;
}

/* ==========================
   これまでの研究・開発
   ========================== */
.pub-columns {
    display: flex;
    flex-wrap: wrap;
    gap: 24px;
    margin-top: 16px;
    align-items: stretch;
}

.pub-col {
    flex: 1 1 320px;
    display: flex;
}

.pub-card {
    background-color: #f0f3ff;
    border-radius: 14px;
    padding: 16px 18px;
    border: 1px solid #d5deff;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.08);
    display: flex;
    flex-direction: column;
}

.pub-card h3 {
    margin-bottom: 8px;
}

.pub-subtitle {
    font-size: 0.9rem;
    margin-top: 12px;
    margin-bottom: 6px;
    color: #444;
}

.pub-link-list {
    list-style: none;
    padding-left: 0;
    margin: 0;
}

.pub-link-list li {
    margin-bottom: 4px;
    font-size: 0.9rem;
}

/* ==========================
   連絡先
   ========================== */
.contact-email {
    margin-top: 16px;
    font-size: 0.95rem;
}

.email,
.email-at {
    font-family: "Consolas", "Menlo", "Courier New", monospace;
}

/* ==========================
   フッター
   ========================== */
.site-footer {
    border-top: 1px solid #e0e3eb;
    background-color: #ffffff;
    padding: 12px 0;
}

.footer-inner {
    text-align: center;
    font-size: 0.8rem;
    color: #666;
}

/* ==========================
   研究日誌カード
   ========================== */
.diary-card-grid {
    margin-top: 16px;
    display: flex;
    flex-wrap: wrap;
    gap: 20px;
}

/* 3枚並ぶサイズ＋少し縦長 */
.diary-card {
    display: block;
    flex: 0 0 calc(33.333% - 20px);
    min-width: 260px;
    max-width: 100%;
    text-decoration: none;
    border-radius: 14px;
    border: 1px solid #e0e3eb;
    background-color: #ffffff;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
    padding: 12px 14px;
    transition: transform 0.15s ease-out,
                box-shadow 0.15s ease-out,
                border-color 0.15s ease-out;
    color: inherit;
    min-height: 340px;
}

.diary-card:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 26px rgba(15, 23, 42, 0.10);
    border-color: #1f6feb66;
}

.diary-card-inner {
    display: flex;
    flex-direction: column;
    gap: 4px;
}

.diary-card-thumb {
    width: 100%;
    height: 190px;
    margin-bottom: 6px;
    overflow: hidden;
    border-radius: 10px;
    background-color: #e5e7f2;
}

.diary-card-thumb img {
    width: 100%;
    height: 100%;
    object-fit: cover;
    display: block;
}

.diary-card-label {
    font-size: 0.8rem;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: #1f6feb;
    margin: 0 0 2px;
}

.diary-card-title {
    margin: 0 0 2px;
    font-weight: 600;
    color: #222;
}

.diary-card-date {
    margin: 0;
    font-size: 0.85rem;
    color: #666;
}

/* ブログトップへのリンク */
.diary-blog-link {
    margin-top: 10px;
    font-size: 0.9rem;
    color: #555;
}

/* ==========================
   研究日誌スライダー用
   ========================== */

/* スライダー全体の枠 */
.diary-slider {
    position: relative;
    margin-top: 16px;
    overflow: hidden; /* トラックをはみ出させない */
}

/* スライダー用ボタン（★色付きに変更） */
.diary-slider-btn {
    position: absolute;
    top: 50%;
    transform: translateY(-50%);
    border: none;
    background-color: #1f6feb;     /* 濃い青 */
    color: #ffffff;                /* 白い矢印 */
    width: 32px;
    height: 32px;
    border-radius: 50%;
    cursor: pointer;
    font-size: 18px;
    display: flex;
    align-items: center;
    justify-content: center;
    box-shadow: 0 5px 14px rgba(15, 23, 42, 0.18);
    transition: background-color 0.15s, transform 0.15s, opacity 0.15s;
    z-index: 2;
}

.diary-slider-btn.prev {
    left: 4px;
}

.diary-slider-btn.next {
    right: 4px;
}

.diary-slider-btn:hover:not(:disabled) {
    background-color: #1552b3;
    transform: translateY(-50%) scale(1.06);
}

.diary-slider-btn:disabled {
    opacity: 0.25;
    cursor: default;
}

/* 横一列に並べるトラック用の上書き */
.diary-card-grid {
    flex-wrap: nowrap;          /* スライドさせるので折り返さない */
    will-change: transform;
    transition: transform 0.4s ease-out;
}

/* ==========================
   レスポンシブ
   ========================== */
@media (max-width: 700px) {
    .header-inner {
        flex-direction: column;
        align-items: flex-start;
        gap: 6px;
    }

    .hero {
        padding-top: 24px;
    }

    .site-nav {
        margin-top: 4px;
    }

    .top-slider-inner {
        height: 320px;
    }

    .top-slider-btn {
        width: 32px;
        height: 32px;
        font-size: 18px;
    }

    .card {
        flex: 1 1 100%;
    }

    .pub-columns {
        flex-direction: column;
    }

    .diary-card {
        flex: 1 1 100%;
    }
}