/* ==========================================================
   AI時代のWebライター講座 受講生サイト
   テーマカラーは https://yamada-yuki.com/ を参考に設定
   ========================================================== */

:root {
    --color-primary: #00ad79;
    --color-primary-dark: #00875e;
    --color-primary-tint: #e6f7f1;
    --color-accent: #ff914d;
    --color-accent-dark: #f2792b;
    --color-bg: #f7f7f7;
    --color-card: #ffffff;
    --color-text: #333333;
    --color-text-light: #767676;
    --color-border: #e6e6e6;
    --radius-lg: 16px;
    --radius-md: 12px;
    --radius-sm: 8px;
    --sidebar-width: 268px;
    --topbar-height: 60px;
    --shadow-soft: 0 4px 16px rgba(0, 0, 0, 0.06);
    --shadow-card: 0 10px 40px rgba(0, 0, 0, 0.12);
}

* {
    box-sizing: border-box;
}

html, body {
    margin: 0;
    padding: 0;
}

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

a {
    color: var(--color-primary);
    text-decoration: none;
}

ul {
    list-style: none;
    margin: 0;
    padding: 0;
}

/* ---------- ボタン ---------- */
.btn {
    display: inline-block;
    padding: 0.8rem 1.75rem;
    border-radius: 999px;
    font-weight: 700;
    font-size: 0.95rem;
    text-decoration: none;
    border: none;
    cursor: pointer;
    text-align: center;
    transition: background-color 0.15s ease, transform 0.1s ease;
}

.btn-primary {
    background: var(--color-primary);
    color: #fff;
}

.btn-primary:hover {
    background: var(--color-primary-dark);
}

.btn-primary:active {
    transform: translateY(1px);
}

/* ==========================================================
   アプリ全体のレイアウト
   ========================================================== */

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

/* ---------- サイドバー ---------- */
.sidebar {
    width: var(--sidebar-width);
    flex-shrink: 0;
    background: var(--color-card);
    border-right: 1px solid var(--color-border);
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    overflow-y: auto;
    z-index: 40;
    transition: transform 0.25s ease;
}

.sidebar-brand {
    padding: 1.5rem 1.25rem;
    background: var(--color-primary);
}

.sidebar-brand-title {
    display: block;
    color: #fff;
    font-weight: 700;
    font-size: 1.02rem;
    line-height: 1.5;
}

.sidebar-brand-title:hover {
    text-decoration: underline;
}

.site-nav {
    padding: 0.75rem 0.9rem 2rem;
}

.nav-category {
    border-bottom: 1px solid var(--color-border);
    padding: 0.6rem 0;
}

.nav-category:last-child {
    border-bottom: none;
}

.nav-category-title {
    margin: 0;
    padding: 0.4rem 0.5rem;
    font-weight: 700;
    font-size: 0.8rem;
    letter-spacing: 0.04em;
    color: var(--color-primary-dark);
}

.nav-page-list {
    padding: 0 0.25rem 0.25rem 0.5rem;
}

.nav-page-link {
    display: block;
    padding: 0.6rem 0.75rem 0.6rem 1.35rem;
    margin-bottom: 0.15rem;
    border-radius: var(--radius-sm);
    font-size: 0.9rem;
    color: var(--color-text-light);
    border-left: 2px solid transparent;
}

.nav-page-link:hover {
    background: var(--color-primary-tint);
    color: var(--color-primary-dark);
}

.nav-page-link.active {
    background: var(--color-primary-tint);
    color: var(--color-primary-dark);
    font-weight: 700;
    border-left-color: var(--color-accent);
}

.sidebar-overlay {
    display: none;
}

/* ---------- メイン領域 ---------- */
.main-wrap {
    margin-left: var(--sidebar-width);
    width: 100%;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

.topbar {
    height: var(--topbar-height);
    background: var(--color-card);
    border-bottom: 1px solid var(--color-border);
    display: flex;
    align-items: center;
    gap: 1rem;
    padding: 0 1.25rem;
    position: sticky;
    top: 0;
    z-index: 20;
}

.topbar-title {
    font-weight: 700;
    flex-grow: 1;
    overflow: hidden;
    text-overflow: ellipsis;
    white-space: nowrap;
}

.topbar-logout {
    font-size: 0.85rem;
    color: var(--color-text-light);
    border: 1px solid var(--color-border);
    padding: 0.4rem 0.9rem;
    border-radius: 999px;
    flex-shrink: 0;
}

.topbar-logout:hover {
    color: var(--color-accent-dark);
    border-color: var(--color-accent);
}

.hamburger {
    display: none;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 5px;
    width: 44px;
    height: 44px;
    background: none;
    border: none;
    cursor: pointer;
    flex-shrink: 0;
    padding: 0;
    margin-left: -0.5rem;
}

.hamburger span {
    display: block;
    height: 2px;
    width: 22px;
    background: var(--color-text);
    border-radius: 2px;
    transition: transform 0.2s ease, opacity 0.2s ease;
}

.hamburger[aria-expanded="true"] span:nth-child(1) {
    transform: translateY(7px) rotate(45deg);
}

.hamburger[aria-expanded="true"] span:nth-child(2) {
    opacity: 0;
}

.hamburger[aria-expanded="true"] span:nth-child(3) {
    transform: translateY(-7px) rotate(-45deg);
}

/* ---------- コンテンツ ---------- */
.content {
    flex-grow: 1;
    width: 100%;
    max-width: 900px;
    margin: 0 auto;
    padding: 2.25rem 1.5rem 4rem;
}

.video-item {
    margin-bottom: 2.5rem;
}

.video-item:last-child {
    margin-bottom: 0;
}

.video-embed {
    position: relative;
    width: 100%;
    height: 0;
    background: #000;
}

.video-embed iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: 0;
}

.not-found {
    font-size: 1.05rem;
    margin-bottom: 1.5rem;
}

.page-resources {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 1rem;
    margin: 1.25rem 0 2rem;
}

.resource-link {
    display: inline-flex;
    align-items: center;
    gap: 0.45rem;
    padding: 0.85rem 1.7rem;
    border-radius: 999px;
    background: linear-gradient(135deg, var(--color-accent) 0%, var(--color-accent-dark) 100%);
    color: #fff;
    font-weight: 700;
    font-size: 0.92rem;
    box-shadow: 0 8px 20px rgba(242, 121, 43, 0.32);
    transition: transform 0.18s ease, box-shadow 0.18s ease;
}

.resource-link::after {
    content: "\2197";
    font-size: 0.85em;
}

.resource-link:hover {
    transform: translateY(-3px);
    box-shadow: 0 12px 26px rgba(242, 121, 43, 0.42);
}

.resource-link:active {
    transform: translateY(-1px);
    box-shadow: 0 6px 14px rgba(242, 121, 43, 0.32);
}

/* ==========================================================
   ログイン画面
   ========================================================== */

.login-page {
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 1.5rem;
    background: linear-gradient(150deg, var(--color-primary) 0%, #00c98f 55%, var(--color-accent) 140%);
}

.login-card {
    width: 100%;
    max-width: 380px;
    background: var(--color-card);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow-card);
    padding: 2.75rem 2.25rem;
    text-align: center;
}

.login-eyebrow {
    color: var(--color-accent-dark);
    font-weight: 700;
    font-size: 0.8rem;
    letter-spacing: 0.08em;
    margin: 0 0 0.4rem;
}

.login-title {
    font-size: 1.25rem;
    color: var(--color-primary-dark);
    margin: 0 0 1.75rem;
    line-height: 1.6;
}

.login-error {
    background: #fdecea;
    color: #c0392b;
    border-radius: var(--radius-sm);
    padding: 0.7rem 0.9rem;
    font-size: 0.85rem;
    margin: 0 0 1.25rem;
}

.login-form {
    text-align: left;
}

.login-form label {
    display: block;
    font-size: 0.85rem;
    color: var(--color-text-light);
    margin-bottom: 0.4rem;
}

.login-form input[type="password"] {
    width: 100%;
    padding: 0.75rem 0.9rem;
    border: 1px solid var(--color-border);
    border-radius: var(--radius-sm);
    font-size: 1rem;
    margin-bottom: 1.5rem;
}

.login-form input[type="password"]:focus {
    outline: none;
    border-color: var(--color-primary);
    box-shadow: 0 0 0 3px var(--color-primary-tint);
}

.login-form .btn {
    width: 100%;
}

/* ==========================================================
   レスポンシブ(900px未満はサイドバーをオフキャンバス化)
   ========================================================== */

@media (max-width: 900px) {
    .hamburger {
        display: flex;
    }

    .sidebar {
        max-width: 85vw;
        transform: translateX(-100%);
        box-shadow: var(--shadow-card);
    }

    .sidebar.is-open {
        transform: translateX(0);
    }

    .sidebar-overlay.is-open {
        display: block;
        position: fixed;
        inset: 0;
        background: rgba(0, 0, 0, 0.35);
        z-index: 30;
    }

    .main-wrap {
        margin-left: 0;
    }

    .content {
        padding: 1.5rem 1.1rem 3rem;
    }
}

@media (max-width: 480px) {
    .topbar {
        padding: 0 0.85rem;
        gap: 0.6rem;
    }

    .topbar-logout {
        padding: 0.35rem 0.7rem;
        font-size: 0.8rem;
    }

    .content {
        padding: 1.25rem 0.9rem 2.5rem;
    }

    .login-card {
        padding: 2rem 1.5rem;
    }

    .page-resources {
        flex-direction: column;
    }

    .resource-link {
        width: 100%;
        justify-content: center;
    }
}