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

html, body {
    height: 100%;
}

/* ===== ヘッダー ===== */

.site-header {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 120px;
    backdrop-filter: blur(10px);
    z-index: 1003;
    transition: backdrop-filter 0.3s ease;
}

.open .site-header {
    backdrop-filter: none;
}

.header-inner {
    display: flex;
    align-items: center;
    height: 100%;
    padding: 0 24px;
}

.header-left,
.header-center,
.header-right {
    flex: 1;
    display: flex;
    align-items: center;
}

.header-left { 
    justify-content: flex-start; 
}

.header-right { 
    justify-content: flex-end; 
}

.header-left img {
    height: 100px;
}

.header-center {
    justify-content: center;
    text-align: center;
}

.header-center h1 {
    font-size: 50px;
    font-weight: 600;
    color: #222;
}

/* ===== ハンバーガー ===== */

.toggle-btn {
    position: relative;
    width: 50px;
    height: 50px;
    cursor: pointer;
    background: #c3e2ee;
    border-radius: 50%;
    box-shadow: 0 5px 15px rgba(0,0,0,0.1);
    z-index: 1003;
}

.toggle-btn span {
    position: absolute;
    left: 50%;
    width: 28px;
    height: 3px;
    background: #222;
    border-radius: 3px;
    transform: translateX(-50%);
    transition: all 0.3s ease;
}

.toggle-btn span:nth-child(1) { top: 16px; }
.toggle-btn span:nth-child(2) { top: 24px; width: 22px; }
.toggle-btn span:nth-child(3) { top: 32px; width: 16px; }

.toggle-btn.open span {
    top: 50%;
    width: 28px;
}

.toggle-btn.open span:nth-child(1) {
    transform: translate(-50%, -50%) rotate(45deg);
}

.toggle-btn.open span:nth-child(2) {
    opacity: 0;
}

.toggle-btn.open span:nth-child(3) {
    transform: translate(-50%, -50%) rotate(-45deg);
}

/* ===== ナビゲーション ===== */

#navArea {
    position: relative;
    z-index: 1001;
}

nav {
    position: fixed;
    top: 0;
    right: -300px;
    width: 300px;
    height: 100vh;
    background: #c3e2ee;
    box-shadow: -5px 0 15px rgba(0,0,0,0.1);
    transition: 0.4s ease;
    z-index: 1002;
}

.open nav {
    right: 0;
}

nav .inner {
    padding: 100px 30px 30px;
}

nav ul {
    list-style: none;
}

nav li {
    margin: 10px 0;
}

nav a {
    display: block;
    padding: 14px 20px;
    text-decoration: none;
    color: #222;
    border-radius: 8px;
    transition: 0.3s;
}

nav a:hover {
    background: rgba(0,0,0,0.05);
    transform: translateX(6px);
}

/* ===== マスク ===== */

#mask {
    position: fixed;
    inset: 0;
    background: rgba(0,0,0,0.4);
    display: none;
    z-index: 1001;
}

.open #mask {
    display: block;
}

/* ===== ページコンテンツ ===== */

.news-page-container {
    margin-top: 120px;
    padding: 40px 5%;
}

.news-page-header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 30px;
    border-bottom: 4px dotted #222;
}

.news-page-header h1 {
    font-size: 40px;
    font-weight: 600;
    color: #222;
    margin-bottom: 10px;
}

.news-page-header p {
    font-size: 16px;
    color: #666;
}

/* ===== ニュースコンテナ ===== */

#news-container {
    max-width: 900px;
    margin: 0 auto;
}

.news-list {
    display: flex;
    flex-direction: column;
    gap: 20px;
}

.news-item {
    background: white;
    border: 2px solid #e0e0e0;
    border-radius: 12px;
    padding: 20px;
    transition: all 0.3s ease;
    overflow: hidden;
}

.news-item:hover {
    border-color: #4FC3F7;
    box-shadow: 0 4px 12px rgba(79, 195, 247, 0.2);
}

.news-item-header {
    display: flex;
    align-items: center;
    gap: 15px;
    margin-bottom: 15px;
    flex-wrap: wrap;
}

.news-date {
    display: inline-block;
    background: #4FC3F7;
    color: white;
    padding: 6px 12px;
    border-radius: 6px;
    font-size: 13px;
    font-weight: 600;
}

.news-title {
    flex: 1;
    font-size: 18px;
    font-weight: 600;
    color: #222;
    line-height: 1.4;
}

.news-content {
    color: #555;
    line-height: 1.6;
    margin-bottom: 15px;
    font-size: 14px;
}

.news-footer {
    display: flex;
    align-items: center;
    justify-content: flex-end;
}

.news-detail-btn {
    background: #4FC3F7;
    color: white;
    border: none;
    padding: 10px 20px;
    border-radius: 6px;
    cursor: pointer;
    font-size: 14px;
    font-weight: 600;
    transition: all 0.3s ease;
    text-decoration: none;
    display: inline-block;
}

.news-detail-btn:hover {
    background: #0288D1;
    transform: translateY(-2px);
    box-shadow: 0 4px 12px rgba(79, 195, 247, 0.3);
}

.news-detail-btn:active {
    transform: translateY(0);
}

.news-detail-btn.hidden {
    display: none;
}

/* ===== エラーメッセージ ===== */

.news-error {
    text-align: center;
    padding: 40px 20px;
    color: #d32f2f;
    font-size: 16px;
    background: #ffebee;
    border-radius: 8px;
    border: 2px solid #d32f2f;
}

/* ===== 空状態 ===== */

.news-empty {
    text-align: center;
    padding: 40px 20px;
    color: #999;
    font-size: 16px;
}

/* ===== レスポンシブ対応 ===== */

@media (max-width: 768px) {
    .site-header {
        height: 80px;
    }

    .header-left img {
        height: 60px;
    }

    .header-center h1 {
        font-size: 18px;
    }

    nav {
        right: auto;
        left: 0;
        top: -100vh;
        width: 100%;
        height: 100vh;
        transition: top 0.5s ease;
    }

    .open nav {
        top: 0;
        right: auto;
    }

    .toggle-btn {
        width: 45px;
        height: 45px;
    }

    nav .inner {
        padding-top: 100px;
    }

    .news-page-container {
        margin-top: 80px;
        padding: 20px 5%;
    }

    .news-page-header h1 {
        font-size: 28px;
    }

    .news-page-header p {
        font-size: 14px;
    }

    .news-item {
        padding: 15px;
    }

    .news-item-header {
        flex-direction: column;
        align-items: flex-start;
    }

    .news-title {
        width: 100%;
        flex: none;
    }

    .news-footer {
        width: 100%;
        margin-top: 10px;
    }

    .news-detail-btn {
        width: 100%;
        text-align: center;
        padding: 12px;
    }
}