/* ==========================================================================
   会員サイト スタイル
   ========================================================================== */

:root {
    --accent: #ff3b5c;
    --accent-dark: #d92a48;
    --sidebar-bg: #14161f;
    --sidebar-text: #aab0c0;
    --bg: #f4f5f8;
    --card: #ffffff;
    --text: #1c1f26;
    --text-sub: #5c6370;
    --border: #e3e6ec;
    --radius: 12px;
    --sidebar-w: 240px;
}

* { margin: 0; padding: 0; box-sizing: border-box; }

/* hidden属性はどのdisplay指定よりも優先する（display:flex等による上書き事故の根治） */
[hidden] { display: none !important; }

body {
    font-family: "Hiragino Sans", "Noto Sans JP", "Yu Gothic", sans-serif;
    background: var(--bg);
    color: var(--text);
    line-height: 1.8;
}

button { font-family: inherit; cursor: pointer; }

/* --------------------------------------------------------------------------
   ログイン画面
   -------------------------------------------------------------------------- */

#login-screen {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(150deg, #14161f 0%, #232738 100%);
    padding: 20px;
}

.login-card {
    background: var(--card);
    border-radius: 16px;
    padding: 48px 40px;
    width: 100%;
    max-width: 420px;
    text-align: center;
    box-shadow: 0 24px 64px rgba(0, 0, 0, 0.4);
}

.login-logo { font-size: 48px; margin-bottom: 12px; }

.login-card h1 { font-size: 20px; margin-bottom: 4px; }

.login-sub { color: var(--text-sub); font-size: 14px; margin-bottom: 28px; }

#password-input {
    width: 100%;
    padding: 14px 16px;
    font-size: 16px;
    border: 2px solid var(--border);
    border-radius: 10px;
    margin-bottom: 12px;
    outline: none;
}

#password-input:focus { border-color: var(--accent); }

#login-button {
    width: 100%;
    padding: 14px;
    font-size: 16px;
    font-weight: 700;
    color: #fff;
    background: var(--accent);
    border: none;
    border-radius: 10px;
    transition: background 0.15s;
}

#login-button:hover { background: var(--accent-dark); }
#login-button:disabled { opacity: 0.6; cursor: wait; }

.login-error { color: var(--accent); font-weight: 700; margin-top: 12px; }

.login-note { color: var(--text-sub); font-size: 12px; margin-top: 20px; }

/* --------------------------------------------------------------------------
   レイアウト
   -------------------------------------------------------------------------- */

#app { display: flex; min-height: 100vh; }

.sidebar {
    width: var(--sidebar-w);
    background: var(--sidebar-bg);
    color: var(--sidebar-text);
    padding: 24px 14px;
    display: flex;
    flex-direction: column;
    gap: 20px;
    position: sticky;
    top: 0;
    height: 100vh;
    flex-shrink: 0;
}

.brand { display: flex; align-items: center; gap: 8px; padding: 0 10px; }
.brand-icon { font-size: 22px; }
.brand-name { color: #fff; font-weight: 700; font-size: 14px; }

.nav { display: flex; flex-direction: column; gap: 4px; }

.nav-item {
    text-align: left;
    padding: 12px 14px;
    background: none;
    border: none;
    border-radius: 8px;
    color: var(--sidebar-text);
    font-size: 14px;
    transition: background 0.15s, color 0.15s;
}

.nav-item:hover { background: rgba(255, 255, 255, 0.06); color: #fff; }
.nav-item.active { background: var(--accent); color: #fff; font-weight: 700; }

.sidebar-footer { margin-top: auto; }

.logout {
    background: none;
    border: 1px solid rgba(255, 255, 255, 0.15);
    color: var(--sidebar-text);
    border-radius: 8px;
    padding: 8px 14px;
    font-size: 12px;
    width: 100%;
}

.main {
    flex: 1;
    padding: 40px clamp(20px, 5vw, 64px);
    max-width: 900px;
}

.tab-heading { font-size: 26px; margin-bottom: 8px; }
.tab-lead { color: var(--text-sub); margin-bottom: 28px; }

/* --------------------------------------------------------------------------
   テキスト講義
   -------------------------------------------------------------------------- */

.chapter-list { display: flex; flex-direction: column; gap: 12px; }

.chapter-card {
    display: flex;
    align-items: center;
    gap: 16px;
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 20px 24px;
    font-size: 16px;
    text-align: left;
    transition: border-color 0.15s, transform 0.1s;
}

.chapter-card:hover { border-color: var(--accent); transform: translateX(4px); }

.chapter-card-num { color: var(--accent); font-weight: 800; font-size: 18px; }
.chapter-card-title { flex: 1; font-weight: 600; }
.chapter-card-arrow { color: var(--text-sub); }

.back-link {
    background: none;
    border: none;
    color: var(--accent);
    font-size: 14px;
    font-weight: 700;
    margin-bottom: 20px;
    padding: 0;
}

.chapter-view h1 { font-size: 26px; margin-bottom: 24px; }

.chapter-nav { display: flex; justify-content: space-between; gap: 12px; margin-top: 48px; }

.chapter-nav-btn {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 12px 18px;
    font-size: 13px;
    color: var(--text);
    max-width: 48%;
}

.chapter-nav-btn:hover { border-color: var(--accent); }

/* --------------------------------------------------------------------------
   本文（Markdown由来）
   -------------------------------------------------------------------------- */

.prose { font-size: 15px; }

.prose h2 {
    font-size: 20px;
    margin: 36px 0 14px;
    padding-bottom: 8px;
    border-bottom: 2px solid var(--accent);
}

.prose h3 { font-size: 16px; margin: 28px 0 10px; }

.prose p { margin-bottom: 14px; }

.prose ul, .prose ol { margin: 0 0 14px 1.4em; }
.prose li { margin-bottom: 4px; }

.prose code {
    background: #eef0f5;
    border-radius: 4px;
    padding: 2px 6px;
    font-size: 0.9em;
    font-family: Menlo, Consolas, monospace;
}

.prose pre {
    background: #14161f;
    color: #e8eaf0;
    border-radius: 10px;
    padding: 16px 20px;
    overflow-x: auto;
    margin-bottom: 18px;
}

.prose pre code { background: none; color: inherit; padding: 0; }

.prose table {
    width: 100%;
    border-collapse: collapse;
    margin-bottom: 18px;
    font-size: 13.5px;
    display: block;
    overflow-x: auto;
}

.prose th, .prose td {
    border: 1px solid var(--border);
    padding: 8px 12px;
    text-align: left;
    background: var(--card);
}

.prose th { background: #eef0f5; white-space: nowrap; }

.prose blockquote {
    border-left: 4px solid var(--accent);
    background: #fff4f6;
    padding: 12px 18px;
    border-radius: 0 8px 8px 0;
    margin-bottom: 16px;
    color: var(--text);
}

.prose hr { border: none; border-top: 1px solid var(--border); margin: 28px 0; }

/* --------------------------------------------------------------------------
   動画講義
   -------------------------------------------------------------------------- */

.video-list { display: flex; flex-direction: column; gap: 28px; }

.video-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    overflow: hidden;
}

.video-frame { position: relative; padding-top: 56.25%; background: #000; }

.video-frame iframe {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    border: none;
}

.video-placeholder {
    padding: 56px 20px;
    text-align: center;
    color: var(--text-sub);
    background: #eef0f5;
    font-weight: 700;
    line-height: 1.6;
}

.video-placeholder small { font-weight: 400; font-size: 12px; }

.video-meta { padding: 18px 22px; }
.video-meta h3 { font-size: 16px; margin-bottom: 6px; }
.video-meta p { color: var(--text-sub); font-size: 13.5px; }

/* --------------------------------------------------------------------------
   FAQ
   -------------------------------------------------------------------------- */

.faq-list { display: flex; flex-direction: column; gap: 10px; margin-bottom: 36px; }

.faq-item {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
}

.faq-item summary {
    padding: 16px 20px;
    font-weight: 700;
    font-size: 14.5px;
    cursor: pointer;
    list-style: none;
    position: relative;
    padding-right: 44px;
}

.faq-item summary::-webkit-details-marker { display: none; }

.faq-item summary::after {
    content: '+';
    position: absolute;
    right: 20px;
    top: 50%;
    transform: translateY(-50%);
    color: var(--accent);
    font-size: 20px;
    font-weight: 800;
}

.faq-item[open] summary::after { content: '−'; }

.faq-answer { padding: 4px 20px 18px; border-top: 1px dashed var(--border); }

.ai-support-card {
    background: linear-gradient(140deg, #14161f 0%, #262b3d 100%);
    color: #e8eaf0;
    border-radius: var(--radius);
    padding: 28px 30px;
}

.ai-support-card h2 { font-size: 18px; margin-bottom: 12px; color: #fff; }
.ai-support-card ol { margin: 12px 0 12px 1.4em; }
.ai-support-card li { margin-bottom: 6px; }

/* --------------------------------------------------------------------------
   ダウンロード
   -------------------------------------------------------------------------- */

.download-card {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 28px 30px;
    margin-bottom: 36px;
}

.download-button {
    display: inline-block;
    background: var(--accent);
    color: #fff;
    font-weight: 700;
    text-decoration: none;
    padding: 14px 28px;
    border-radius: 10px;
    margin: 14px 0;
}

.download-button:hover { background: var(--accent-dark); }

.download-note { color: var(--text-sub); font-size: 12.5px; }

.changelog-heading { font-size: 18px; margin-bottom: 16px; }

.changelog-entry {
    background: var(--card);
    border: 1px solid var(--border);
    border-radius: 10px;
    padding: 16px 20px;
    margin-bottom: 10px;
    font-size: 13.5px;
}

.changelog-head { display: flex; gap: 12px; align-items: baseline; margin-bottom: 6px; }
.changelog-head span { color: var(--text-sub); font-size: 12px; }
.changelog-entry ul { margin-left: 1.3em; }

/* --------------------------------------------------------------------------
   モバイル
   -------------------------------------------------------------------------- */

@media (max-width: 760px) {
    #app { flex-direction: column; }

    .sidebar {
        width: 100%;
        height: auto;
        position: static;
        flex-direction: row;
        align-items: center;
        flex-wrap: wrap;
        gap: 10px;
        padding: 12px 14px;
    }

    .brand { width: 100%; }
    .nav { flex-direction: row; flex-wrap: wrap; gap: 6px; }
    .nav-item { padding: 8px 12px; font-size: 12.5px; }
    .sidebar-footer { margin: 0; margin-left: auto; }
    .logout { width: auto; padding: 6px 10px; }
    .main { padding: 24px 16px; }
}

/* 本文内の画像（テロップカタログ等） */
.prose img {
    max-width: 100%;
    border-radius: 10px;
    border: 1px solid var(--border);
    display: block;
    margin: 6px 0 4px;
}