/* リセット & ベーススタイル */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    font-family: 'Helvetica Neue', Arial, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background-color: #0a0a0a;
    color: #ffffff;
    line-height: 1.6;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

/* コンテナ */
.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 0 20px;
    width: 100%;
}

/* ナビゲーションバー */
.navbar {
    background-color: rgba(0, 0, 0, 0.95);
    padding: 1.2rem 0;
    position: fixed;
    top: 0;
    width: 100%;
    z-index: 1000;
    backdrop-filter: blur(10px);
    border-bottom: 1px solid #222;
    transition: transform 0.3s ease;
}

.navbar.hidden {
    transform: translateY(-100%);
}

.navbar .container {
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.logo img {
    height: 45px;
    padding: 0;
    margin: 0;
}

.logo h1 {
    font-size: 1.8rem;
    font-weight: 300;
    letter-spacing: 2px;
    color: #ffffff;
}

.logo .subtitle {
    color: #888;
    font-size: 1rem;
    margin-left: 0.3rem;
}

.nav-links {
    display: flex;
    list-style: none;
    gap: 2rem;
}

.nav-links a {
    color: #ffffff;
    text-decoration: none;
    font-size: 0.95rem;
    font-weight: 300;
    letter-spacing: 1px;
    transition: color 0.3s ease;
    position: relative;
}

.nav-links a::after {
    content: '';
    position: absolute;
    bottom: -5px;
    left: 0;
    width: 0;
    height: 1px;
    background-color: #ffffff;
    transition: width 0.3s ease;
}

.nav-links a:hover {
    color: #ccc;
}

.nav-links a:hover::after {
    width: 100%;
}

/* ハンバーガーメニュー */
.hamburger {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: 8px;
    z-index: 1001;
}

.hamburger span {
    display: block;
    width: 28px;
    height: 2px;
    background-color: #ffffff;
    transition: all 0.3s ease;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(45deg) translate(7px, 7px);
}

.hamburger.active span:nth-child(2) {
    opacity: 0;
}

.hamburger.active span:nth-child(3) {
    transform: rotate(-45deg) translate(7px, -7px);
}

/* ヒーローバナー */
.hero-banner {
    min-height: 90vh;
    background: linear-gradient(135deg, #1a1a1a 0%, #0a0a0a 100%),
                url('../img/hero_bg.jpg') center bottom/cover no-repeat;
    background-blend-mode: overlay;
    display: flex;
    align-items: center;
    justify-content: center;
    position: relative;
    padding: 6rem 20px 4rem;
    margin-top: 70px;
}

.overlay {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.2);
    z-index: 1;
}

.hero-content {
    position: relative;
    z-index: 2;
    text-align: center;
    max-width: 1000px;
}

.hero-title {
    font-size: 4rem;
    font-weight: 100;
    letter-spacing: 8px;
    margin-bottom: 1rem;
    text-transform: none;
    animation: fadeInUp 1s ease;
}

.hero-subtitle {
    font-size: 1.5rem;
    font-weight: 300;
    letter-spacing: 4px;
    color: #aaa;
    margin-bottom: 4rem;
    animation: fadeInUp 1.2s ease;
}

/* ソーシャルグリッド */
/* Bootstrap5グリッドシステムに移行 - .social-grid は不要 */

.social-item {
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid rgba(255, 255, 255, 0.1);
    border-radius: 12px;
    padding: 2rem 1.5rem;
    text-decoration: none;
    color: #ffffff;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 1rem;
    transition: all 0.3s ease;
    backdrop-filter: blur(10px);
}

.social-item:hover {
    background: rgba(255, 255, 255, 0.1);
    border-color: rgba(255, 255, 255, 0.3);
    transform: translateY(-5px);
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.5);
}

.social-icon {
    width: 50px;
    height: 50px;
    display: flex;
    align-items: center;
    justify-content: center;
}

.social-icon svg {
    width: 100%;
    height: 100%;
    transition: transform 0.3s ease;
}

.social-item:hover .social-icon svg {
    transform: scale(1.1);
}

.social-item span {
    font-size: 0.9rem;
    font-weight: 300;
    letter-spacing: 1px;
}

/* フッター */
.footer {
    background-color: #000000;
    padding: 3rem 0 1.5rem;
    margin-top: auto;
    border-top: 1px solid #222;
}

/* Bootstrap5グリッドシステムに移行 - .footer-content は不要 */

.footer h3 {
    font-size: 1.5rem;
    font-weight: 300;
    letter-spacing: 2px;
    margin-bottom: 1rem;
}

.footer h4 {
    font-size: 1.1rem;
    font-weight: 400;
    letter-spacing: 1px;
    margin-bottom: 0.8rem;
    color: #ccc;
}

.footer p {
    color: #888;
    font-size: 0.9rem;
    font-weight: 300;
    line-height: 1.8;
}

.footer-bottom {
    text-align: center;
    padding-top: 2rem;
    border-top: 1px solid #222;
}

.footer-bottom p {
    color: #666;
    font-size: 0.85rem;
    font-weight: 300;
    letter-spacing: 1px;
}

/* アニメーション */
@keyframes fadeInUp {
    from {
        opacity: 0;
        transform: translateY(30px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* レスポンシブ対応 */
@media (max-width: 768px) {
    .navbar .container {
        flex-wrap: wrap;
        position: relative;
    }

    .hamburger {
        display: flex;
    }

    .logo h1 {
        font-size: 1.5rem;
    }

    .nav-links {
        position: fixed;
        top: 0;
        right: -100%;
        height: 100vh;
        width: 70%;
        max-width: 300px;
        background-color: rgba(0, 0, 0, 0.98);
        flex-direction: column;
        justify-content: center;
        align-items: center;
        gap: 2rem;
        transition: right 0.3s ease;
        padding: 2rem;
        backdrop-filter: blur(10px);
        border-left: 1px solid #222;
    }

    .nav-links.active {
        right: 0;
    }

    .nav-links a {
        font-size: 1.1rem;
    }

    .hero-banner {
        margin-top: 120px;
        padding: 4rem 15px 3rem;
    }

    .hero-title {
        font-size: 2.5rem;
        letter-spacing: 4px;
    }

    .hero-subtitle {
        font-size: 1.2rem;
        letter-spacing: 2px;
        margin-bottom: 3rem;
    }

    .social-item {
        padding: 1.5rem 1rem;
    }

    .social-icon {
        width: 40px;
        height: 40px;
    }

    .social-item span {
        font-size: 0.8rem;
    }
}

@media (max-width: 480px) {
    .hero-title {
        font-size: 2rem;
        letter-spacing: 3px;
    }

    .hero-subtitle {
        font-size: 1rem;
    }
}