:root {
    --primary-color: #0d6efd;
    --secondary-color: #6c757d;
    --success-color: #198754;
    --gradient-start: #667eea;
    --gradient-end: #764ba2;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    line-height: 1.6;
    color: #2d3748;
    background: #f8f9fa;
    overflow-x: hidden;
}

/* スムーズスクロール */
html {
    scroll-behavior: smooth;
}

/* ナビゲーション */
.navbar {
    backdrop-filter: blur(10px);
    background-color: rgba(255, 255, 255, 0.98) !important;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border-bottom: 1px solid #e2e8f0;
}

.navbar-brand {
    font-size: 1.5rem;
    font-weight: 700;
    display: flex;
    align-items: center;
    color: #2d3748 !important;
}

.navbar-brand strong {
    color: #2d3748 !important;
}

.navbar-brand img {
    transition: transform 0.3s ease;
}

.navbar-brand:hover img {
    transform: scale(1.1);
}

/* より強力なセレクタでBootstrapをオーバーライド */
.navbar-light .navbar-nav .nav-link,
.navbar-light .navbar-nav .nav-link:focus,
.navbar-light .navbar-nav .nav-link:visited,
.navbar-light .navbar-nav .show>.nav-link,
.navbar-light .navbar-nav .active>.nav-link,
.navbar-light .navbar-nav .nav-link.show,
.navbar-light .navbar-nav .nav-link.active {
    font-weight: 500;
    margin: 0 0.5rem;
    transition: all 0.3s ease;
    color: #4a5568 !important;
}

.navbar-light .navbar-nav .nav-link:hover {
    transform: translateY(-2px);
    color: #667eea !important;
}

.navbar-light .navbar-nav .nav-link i,
.navbar-light .navbar-nav .nav-link:focus i,
.navbar-light .navbar-nav .nav-link:visited i {
    color: #4a5568 !important;
}

/* 言語ドロップダウン */
.navbar-light .navbar-nav .dropdown-toggle,
.navbar-light .navbar-nav .dropdown-toggle:focus,
.navbar-light .navbar-nav .dropdown-toggle:visited {
    color: #4a5568 !important;
}

.navbar-light .navbar-nav .dropdown-toggle:hover {
    color: #667eea !important;
}

.navbar-light .navbar-nav .dropdown-toggle i,
.navbar-light .navbar-nav .dropdown-toggle:focus i,
.navbar-light .navbar-nav .dropdown-toggle:visited i {
    color: #4a5568 !important;
}

/* currentLangのテキスト色 */
#currentLang {
    color: #4a5568 !important;
}

/* ヒーローセクション */
.hero-section {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 80px 0;
    position: relative;
    overflow: hidden;
}

.hero-section::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    bottom: 0;
    background: url('data:image/svg+xml,<svg width="100" height="100" xmlns="http://www.w3.org/2000/svg"><circle cx="50" cy="50" r="2" fill="white" opacity="0.05"/></svg>');
    animation: float 20s infinite linear;
}

.hero-logo {
    filter: drop-shadow(0 10px 30px rgba(0, 0, 0, 0.3));
    transition: transform 0.3s ease;
}

.hero-logo:hover {
    transform: scale(1.05);
}

.hero-section .container {
    position: relative;
    z-index: 1;
}

.hero-section h1 {
    font-size: 4rem;
    font-weight: 800;
    text-shadow: 2px 2px 4px rgba(0, 0, 0, 0.2);
}

.hero-section .lead {
    font-size: 1.5rem;
    font-weight: 300;
}

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

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

.animate-fade-in {
    animation: fadeIn 0.8s ease-out;
}

.animate-fade-in-delay-1 {
    animation: fadeIn 0.8s ease-out 0.2s backwards;
}

.animate-fade-in-delay-2 {
    animation: fadeIn 0.8s ease-out 0.4s backwards;
}

.animate-fade-in-delay-3 {
    animation: fadeIn 0.8s ease-out 0.6s backwards;
}

/* セクション共通 */
.section-padding {
    padding: 100px 0;
}

.bg-light {
    background-color: #f8f9fa !important;
}

/* ドロップダウンメニュー */
.dropdown-menu {
    border: 1px solid #e2e8f0;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
}

.dropdown-item {
    color: #4a5568;
    transition: all 0.2s ease;
}

.dropdown-item:hover {
    background-color: #f7fafc;
    color: #667eea;
}

/* 特徴カード */
.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.feature-icon {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    border-radius: 20px;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    box-shadow: 0 5px 15px rgba(102, 126, 234, 0.3);
}

.feature-icon i {
    font-size: 2.5rem;
    color: white;
}

/* ステップ番号 */
.step-number {
    width: 80px;
    height: 80px;
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    font-size: 2.5rem;
    font-weight: bold;
    color: white;
    box-shadow: 0 5px 20px rgba(102, 126, 234, 0.3);
}

/* スクリーンショットカード */
.screenshot-card {
    background: white;
    border-radius: 12px;
    overflow: hidden;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

.screenshot-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.screenshot-card img {
    width: 100%;
    height: auto;
    transition: transform 0.3s ease;
}

.screenshot-card:hover img {
    transform: scale(1.05);
}

/* 技術カード */
.tech-card {
    padding: 2rem;
    background: white;
    border-radius: 12px;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.08);
    transition: all 0.3s ease;
    border: 1px solid #e2e8f0;
}

.tech-card:hover {
    transform: translateY(-3px);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.12);
}

.tech-icon {
    font-size: 3rem;
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    background-clip: text;
    margin-bottom: 1rem;
}

/* ボタン */
.btn {
    padding: 0.625rem 1.25rem;
    font-weight: 500;
    border-radius: 8px;
    transition: all 0.2s ease;
}

.btn-primary {
    background: linear-gradient(135deg, var(--gradient-start) 0%, var(--gradient-end) 100%);
    border: none;
}

.btn-primary:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(102, 126, 234, 0.4);
}

.btn-outline-secondary {
    background-color: rgba(255, 255, 255, 0.95);
    border: 1px solid #e2e8f0;
    color: #4a5568;
}

.btn-outline-secondary:hover {
    transform: translateY(-1px);
    background-color: white;
    border-color: #e2e8f0;
    color: #2d3748;
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
}

.btn-light {
    background-color: white;
    color: #667eea;
    border: 1px solid #e2e8f0;
}

.btn-light:hover {
    transform: translateY(-1px);
    box-shadow: 0 2px 8px rgba(0, 0, 0, 0.1);
    background-color: #f7fafc;
    color: #667eea;
}

/* フッター */
footer {
    padding: 3rem 0 2rem;
    background-color: #2d3748 !important;
}

footer h5 {
    color: #ffffff;
}

footer p {
    color: #cbd5e0;
}

footer a {
    transition: all 0.3s ease;
    color: #cbd5e0 !important;
}

footer a:hover {
    color: #ffffff !important;
    transform: translateX(5px);
}

footer .text-muted {
    color: #a0aec0 !important;
}

footer hr {
    border-color: #4a5568 !important;
    opacity: 0.3;
}

/* レスポンシブ */
@media (max-width: 991px) {
    .hero-section h1 {
        font-size: 2.5rem;
    }

    .hero-section .lead {
        font-size: 1.2rem;
    }

    .navbar-nav .nav-link {
        margin: 0.5rem 0;
    }

    .section-padding {
        padding: 60px 0;
    }
}

@media (max-width: 768px) {
    .hero-section h1 {
        font-size: 2rem;
    }

    .display-5 {
        font-size: 2rem;
    }

    .feature-card,
    .screenshot-card {
        margin-bottom: 1.5rem;
    }
}

/* スクロールバー */
::-webkit-scrollbar {
    width: 8px;
}

::-webkit-scrollbar-track {
    background: transparent;
}

::-webkit-scrollbar-thumb {
    background: #cbd5e0;
    border-radius: 4px;
}

::-webkit-scrollbar-thumb:hover {
    background: #a0aec0;
}

/* ローディングアニメーション */
@keyframes pulse {

    0%,
    100% {
        opacity: 1;
    }

    50% {
        opacity: 0.5;
    }
}

.pulse {
    animation: pulse 2s ease-in-out infinite;
}