:root {
    --bg: #ffffff;
    --panel: #ffffff;
    --panel-2: #f1f3f9;
    --border: #e1e4ee;
    --text: #1c2033;
    --muted: #6b7288;
    --accent: #4a6cf7;
    --accent-2: #8358f0;
}

* { box-sizing: border-box; }

body {
    margin: 0;
    font-family: "Hiragino Kaku Gothic ProN", "Yu Gothic", "Segoe UI", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.7;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

.container { max-width: 1080px; margin: 0 auto; padding: 0 20px; }

header.site-header {
    border-bottom: 1px solid var(--border);
    background: rgba(255, 255, 255, 0.85);
    backdrop-filter: blur(6px);
    position: sticky;
    top: 0;
    z-index: 10;
}

.site-header .bar {
    display: flex;
    align-items: center;
    gap: 20px;
    padding: 14px 20px;
    max-width: 1080px;
    margin: 0 auto;
    flex-wrap: wrap;
}

.main-nav {
    display: flex;
    align-items: center;
    gap: 4px;
    font-size: 0.9rem;
}

.main-nav > a,
.main-nav summary {
    padding: 7px 12px;
    border-radius: 8px;
    color: var(--muted);
    cursor: pointer;
    list-style: none;
    user-select: none;
}
.main-nav > a::-webkit-details-marker,
.main-nav summary::-webkit-details-marker { display: none; }
.main-nav summary::marker { display: none; content: ""; }

.main-nav > a:hover,
.main-nav summary:hover {
    background: var(--panel-2);
    color: var(--text);
    text-decoration: none;
}

.main-nav > a.active,
.main-nav summary.active {
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    color: #fff;
}

.nav-dropdown { position: relative; }

.nav-dropdown-menu {
    position: absolute;
    top: calc(100% + 6px);
    left: 0;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 6px;
    min-width: 200px;
    box-shadow: 0 12px 30px rgba(20, 24, 50, 0.12);
    z-index: 20;
    display: flex;
    flex-direction: column;
}

.nav-dropdown-menu a {
    padding: 8px 10px;
    border-radius: 6px;
    color: var(--text);
    font-size: 0.88rem;
}
.nav-dropdown-menu a:hover {
    background: var(--panel-2);
    text-decoration: none;
}

.nav-links { margin-left: auto; }

.search-form {
    display: flex;
    align-items: center;
    margin-left: 8px;
}
.search-form input {
    width: 150px;
    padding: 7px 10px;
    border-radius: 8px 0 0 8px;
    border: 1px solid var(--border);
    border-right: none;
    background: var(--panel-2);
    color: var(--text);
    font-size: 0.85rem;
}
.search-form button {
    border-radius: 0 8px 8px 0;
    padding: 7px 12px;
    font-size: 0.9rem;
}

.logo {
    font-weight: 700;
    font-size: 1.3rem;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    -webkit-background-clip: text;
    background-clip: text;
    color: transparent;
}

.nav-links { display: flex; gap: 16px; align-items: center; font-size: 0.92rem; }
.nav-links .muted { color: var(--muted); }

main { padding: 30px 0 60px; }

.page-title { font-size: 1.5rem; margin-bottom: 4px; }
.page-sub { color: var(--muted); margin-bottom: 24px; font-size: 0.95rem; }

.card {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 18px 20px;
    margin-bottom: 14px;
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}

.category-list .card { display: flex; justify-content: space-between; align-items: center; }
.category-list h2 { margin: 0 0 4px; font-size: 1.1rem; }
.category-list p { margin: 0; color: var(--muted); font-size: 0.88rem; }
.category-list .count { color: var(--muted); font-size: 0.85rem; white-space: nowrap; padding-left: 16px; }

.thread-row {
    display: flex;
    align-items: center;
    gap: 14px;
}

.thread-row-body {
    flex: 1;
    min-width: 0;
    display: flex;
    justify-content: space-between;
    align-items: center;
    gap: 12px;
}

.thread-thumb {
    flex-shrink: 0;
    width: 110px;
    height: 78px;
    border-radius: 8px;
    overflow: hidden;
    display: block;
    background: var(--panel-2);
}
.thread-thumb img { width: 100%; height: 100%; object-fit: cover; display: block; }

.thread-row .meta { color: var(--muted); font-size: 0.82rem; margin-top: 4px; }
.thread-row .stats { text-align: right; color: var(--muted); font-size: 0.82rem; white-space: nowrap; }
.pin-badge {
    display: inline-block;
    font-size: 0.72rem;
    background: var(--accent-2);
    color: #fff;
    border-radius: 6px;
    padding: 1px 6px;
    margin-right: 6px;
}

.breadcrumb { font-size: 0.85rem; color: var(--muted); margin-bottom: 16px; }
.breadcrumb a { color: var(--muted); }

.post {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 16px 20px;
    margin-bottom: 12px;
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.post .post-head {
    display: flex;
    justify-content: space-between;
    color: var(--muted);
    font-size: 0.82rem;
    margin-bottom: 8px;
}
.post .post-head strong { color: var(--text); }
.post .post-body { white-space: pre-wrap; word-break: break-word; }

form.stack { display: flex; flex-direction: column; gap: 12px; }
label { font-size: 0.88rem; color: var(--muted); }

input[type=text], input[type=email], input[type=password], textarea, select {
    width: 100%;
    padding: 10px 12px;
    border-radius: 8px;
    border: 1px solid var(--border);
    background: var(--panel-2);
    color: var(--text);
    font-size: 0.95rem;
    font-family: inherit;
}
textarea { resize: vertical; min-height: 120px; }

button, .btn {
    display: inline-block;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    color: #fff;
    border: none;
    padding: 10px 18px;
    border-radius: 8px;
    font-size: 0.95rem;
    cursor: pointer;
    text-align: center;
}
button:hover, .btn:hover { opacity: 0.9; text-decoration: none; }

.alert {
    padding: 10px 14px;
    border-radius: 8px;
    margin-bottom: 16px;
    font-size: 0.9rem;
}
.alert-error { background: #fde8ec; color: #c22b48; border: 1px solid #f6c1cd; }
.alert-success { background: #e4f7ec; color: #1f8a4c; border: 1px solid #bcebce; }

.pagination {
    display: flex;
    justify-content: center;
    align-items: center;
    gap: 16px;
    margin-top: 24px;
    font-size: 0.9rem;
}

.rank-badge {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-width: 26px;
    height: 26px;
    padding: 0 4px;
    border-radius: 8px;
    background: var(--panel-2);
    border: 1px solid var(--border);
    color: var(--muted);
    font-size: 0.8rem;
    font-weight: 700;
    flex-shrink: 0;
}

.section-head {
    display: flex;
    justify-content: space-between;
    align-items: baseline;
    margin: 36px 0 14px;
}
.section-head h2 { font-size: 1.15rem; margin: 0; }
.section-head a { font-size: 0.85rem; }

/* 注目ニュース: 画像付きカードのグリッド（横並び） */
.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(230px, 1fr));
    gap: 16px;
}

.feature-card {
    display: flex;
    flex-direction: column;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    color: var(--text);
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.feature-card:hover { border-color: var(--accent); text-decoration: none; }

.feature-card-img {
    height: 130px;
    background-size: cover;
    background-position: center;
    background-color: var(--panel-2);
}

.feature-card-body { padding: 12px 14px 16px; display: flex; flex-direction: column; gap: 6px; }
.feature-card-cat { font-size: 0.75rem; color: var(--accent); }
.feature-card-body h3 { margin: 0; font-size: 0.98rem; line-height: 1.45; }
.feature-card-meta { font-size: 0.78rem; color: var(--muted); margin-top: auto; }

/* カテゴリタイル: アイコン付きグリッド（横並び） */
.category-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(150px, 1fr));
    gap: 12px;
}
.category-tile {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 6px;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 18px 10px;
    color: var(--text);
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.category-tile:hover { border-color: var(--accent); text-decoration: none; }
.category-tile .icon { font-size: 1.8rem; }
.category-tile .name { font-size: 0.85rem; font-weight: 600; }
.category-tile .count { font-size: 0.72rem; color: var(--muted); }

/* ホーム下部: 本文＋サイドバーの2カラム */
.layout-split {
    display: grid;
    grid-template-columns: 2fr 1fr;
    gap: 24px;
    align-items: start;
}
@media (max-width: 720px) {
    .layout-split { grid-template-columns: 1fr; }
}

.sidebar-widget {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 16px 18px;
    margin-bottom: 16px;
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.sidebar-widget h3 { margin: 0 0 12px; font-size: 0.95rem; }

.mini-thread-list { display: flex; flex-direction: column; gap: 10px; }
.mini-thread-list a { color: var(--text); font-size: 0.87rem; line-height: 1.4; display: block; }
.mini-thread-list a:hover { color: var(--accent); text-decoration: none; }
.mini-thread-list .mini-meta { font-size: 0.74rem; color: var(--muted); margin-top: 2px; }

/* アバター */
.avatar {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 50%;
    font-weight: 700;
    color: #fff;
    flex-shrink: 0;
}

.avatar-row { display: flex; flex-wrap: wrap; gap: 10px; }
.avatar-chip {
    display: flex;
    align-items: center;
    gap: 8px;
    background: var(--panel-2);
    border-radius: 20px;
    padding: 4px 12px 4px 4px;
    font-size: 0.82rem;
    color: var(--text);
}
.avatar-chip:hover { background: var(--border); text-decoration: none; }

/* メンバー一覧グリッド */
.member-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 14px;
}
.member-card {
    display: flex;
    flex-direction: column;
    align-items: center;
    text-align: center;
    gap: 8px;
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    padding: 22px 16px;
    color: var(--text);
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.member-card:hover { border-color: var(--accent); text-decoration: none; }
.member-card .username { font-weight: 700; }
.member-card .bio {
    font-size: 0.8rem;
    color: var(--muted);
    display: -webkit-box;
    -webkit-line-clamp: 2;
    -webkit-box-orient: vertical;
    overflow: hidden;
}
.member-card .stat { font-size: 0.76rem; color: var(--muted); }

/* プロフィールヘッダー */
.profile-head {
    display: flex;
    gap: 18px;
    align-items: center;
    margin-bottom: 24px;
}
.profile-head .stat-row { display: flex; gap: 16px; margin-top: 6px; font-size: 0.85rem; color: var(--muted); }

/* 「サイトについて」ページ: 画像と本文を1つのカードにまとめる */
.about-card {
    background: var(--panel);
    border: 1px solid var(--border);
    border-radius: 12px;
    overflow: hidden;
    margin-bottom: 14px;
    box-shadow: 0 1px 3px rgba(20, 24, 50, 0.05);
}
.about-card img {
    width: 100%;
    max-height: 420px;
    object-fit: contain;
    background: var(--panel-2);
    display: block;
}
.about-card .about-body {
    padding: 20px 24px;
    white-space: pre-wrap;
    word-break: break-word;
}

/* スレッド詳細ページのカバー画像 */
.thread-cover {
    width: 100%;
    max-height: 320px;
    object-fit: cover;
    border-radius: 12px;
    margin-bottom: 18px;
    display: block;
}

footer.site-footer {
    text-align: center;
    color: var(--muted);
    font-size: 0.8rem;
    padding: 24px 0 40px;
}