/* 基本スタイル */
:root {
    --primary-color: #2c3e50;
    --secondary-color: #3498db;
    --accent-color: #e74c3c;
    --text-color: #333;
    --light-bg: #f5f6fa;
    --header-height: 80px;
}

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

body {
    font-family: 'Noto Sans JP', 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
}

/* ヘッダーとナビゲーション */
header {
    position: fixed;
    top: 0;
    width: 100%;
    background: rgba(255, 255, 255, 0.95);
    box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    z-index: 1000;
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 1rem 5%;
    max-width: 1400px;
    margin: 0 auto;
}

.logo a {
    font-size: 1.5rem;
    font-weight: 700;
    color: var(--primary-color);
    text-decoration: none;
}

.nav-links {
    display: flex;
    list-style: none;
}

.nav-links li {
    margin-left: 2rem;
}

.nav-links a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s ease;
}

.nav-links a:hover,
.nav-links a.active {
    color: var(--secondary-color);
}

/* ハンバーガーメニュー */
.burger {
    display: none;
    cursor: pointer;
}

.burger div {
    width: 25px;
    height: 3px;
    background-color: var(--primary-color);
    margin: 5px;
    transition: all 0.3s ease;
}

/* メインコンテンツ */
main {
    margin-top: var(--header-height);
    min-height: calc(100vh - var(--header-height));
}

/* パララックス効果（ホームページのみ） */
.parallax {
    position: relative;
    overflow: hidden;
    background-attachment: fixed;
    background-position: center;
    background-repeat: no-repeat;
    background-size: cover;
}

/* セクションスタイル */
section {
    padding: 4rem 5%;
}

.page-header {
    background-color: var(--light-bg);
    text-align: center;
    padding: 3rem 1rem;
}

h1 {
    font-size: 2.5rem;
    color: var(--primary-color);
    margin-bottom: 1rem;
}

h2 {
    font-size: 2rem;
    color: var(--primary-color);
    margin-bottom: 2rem;
}

/* 展示情報グリッド */
.exhibition-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.exhibition-item {
    background: white;
    border-radius: 8px;
    overflow: hidden;
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
    transition: transform 0.3s ease;
}

.exhibition-item:hover {
    transform: translateY(-5px);
}

.exhibition-image {
    width: 100%;
    height: 300px;
    object-fit: cover;
    transition: transform 0.3s ease;
}

.exhibition-item:hover .exhibition-image {
    transform: scale(1.05);
}

/* ボタンスタイル */
.btn {
    display: inline-block;
    padding: 0.8rem 1.5rem;
    background-color: var(--secondary-color);
    color: white;
    text-decoration: none;
    border-radius: 5px;
    transition: background-color 0.3s ease;
}

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

/* フッター */
footer {
    background-color: var(--primary-color);
    color: white;
    padding: 3rem 5% 1rem;
}

.footer-content {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 2rem;
    max-width: 1400px;
    margin: 0 auto;
}

.footer-section h3 {
    margin-bottom: 1rem;
}

.social-icons a {
    color: white;
    margin-right: 1rem;
    font-size: 1.5rem;
    transition: color 0.3s ease;
}

.social-icons a:hover {
    color: var(--secondary-color);
}

.footer-bottom {
    text-align: center;
    margin-top: 2rem;
    padding-top: 1rem;
    border-top: 1px solid rgba(255,255,255,0.1);
}

/* レスポンシブデザイン */
@media screen and (max-width: 768px) {
    .burger {
        display: block;
    }

    .nav-links {
        position: absolute;
        right: 0;
        top: var(--header-height);
        background: white;
        height: calc(100vh - var(--header-height));
        width: 100%;
        flex-direction: column;
        align-items: center;
        transform: translateX(100%);
        transition: transform 0.5s ease-in;
        box-shadow: 0 2px 5px rgba(0,0,0,0.1);
    }

    .nav-links li {
        margin: 2rem 0;
        opacity: 0;
    }

    .nav-active {
        transform: translateX(0%);
    }

    @keyframes navLinkFade {
        from {
            opacity: 0;
            transform: translateX(50px);
        }
        to {
            opacity: 1;
            transform: translateX(0px);
        }
    }

    .toggle .line1 {
        transform: rotate(-45deg) translate(-5px, 6px);
    }

    .toggle .line2 {
        opacity: 0;
    }

    .toggle .line3 {
        transform: rotate(45deg) translate(-5px, -6px);
    }
}

/* アニメーション */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.fade-in {
    animation: fadeIn 1s ease-out forwards;
}

/* ホームページ専用スタイル */
.hero {
    background-image: linear-gradient(rgba(0, 0, 0, 0.5), rgba(0, 0, 0, 0.5)), var(--hero-image);
    background-position: center;
    background-size: cover;
    height: 100vh;
}

.hero::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.5);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    max-width: 800px;
    padding: 0 2rem;
}

.hero h1 {
    font-size: 3.5rem;
    margin-bottom: 1.5rem;
    color: white;
}

.hero p {
    font-size: 1.5rem;
    margin-bottom: 2rem;
}

.highlights {
    background-image: linear-gradient(rgba(0, 0, 0, 0.7), rgba(0, 0, 0, 0.7)), var(--highlights-bg);
    background-position: center;
    background-size: cover;
    color: white;
    position: relative;
    padding: 6rem 0;
}

.highlights::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: rgba(0, 0, 0, 0.7);
    z-index: 1;
}

.highlights-content {
    position: relative;
    z-index: 2;
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 2rem;
}

.highlights-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 3rem;
    margin-top: 3rem;
}

.highlight-item {
    text-align: center;
}

.highlight-item i {
    font-size: 3rem;
    margin-bottom: 1.5rem;
    color: var(--secondary-color);
}

.highlight-item h3 {
    font-size: 1.5rem;
    margin-bottom: 1rem;
}

.news-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin-top: 2rem;
}

.news-item {
    background: white;
    padding: 2rem;
    border-radius: 8px;
    box-shadow: 0 2px 15px rgba(0,0,0,0.1);
}

.news-item time {
    color: var(--secondary-color);
    font-weight: 500;
}

.news-item h3 {
    margin: 1rem 0;
    font-size: 1.25rem;
}

.news-item p {
    margin-bottom: 1.5rem;
}

/* レスポンシブ調整 */
@media screen and (max-width: 768px) {
    .hero h1 {
        font-size: 2.5rem;
    }

    .hero p {
        font-size: 1.2rem;
    }

    .highlights {
        padding: 4rem 0;
    }

    .highlights-grid {
        gap: 2rem;
    }

    .news-grid {
        grid-template-columns: 1fr;
    }
}