/* 基本設定：ウェブサイト全体の見た目を整えます */
:root {
    --bg-color: #0a0a0c;
    --text-color: #ffffff;
    --accent-color: #007bff; /* Unityをイメージした青 */
    --font-main: 'Inter', sans-serif;
    --font-heading: 'Outfit', sans-serif;
}

body {
    margin: 0;
    padding: 0;
    background-color: var(--bg-color);
    color: var(--text-color);
    font-family: var(--font-main);
    line-height: 1.6;
}

/* ヘッダー：画面上部のナビゲーション */
header {
    padding: 20px 50px;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

nav ul {
    list-style: none;
    display: flex;
    gap: 20px;
}

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

nav a:hover {
    color: var(--accent-color);
}

.lang-switch-item {
    display: flex;
    align-items: center;
}

.lang-btn {
    background: transparent;
    border: 1px solid var(--text-color);
    color: var(--text-color);
    padding: 5px 12px;
    border-radius: 20px;
    cursor: pointer;
    font-size: 0.8rem;
    font-weight: bold;
    transition: all 0.3s ease;
    margin-left: 10px;
}

.lang-btn:hover {
    background: var(--text-color);
    color: var(--bg-color);
}

/* ヒーローセクション：一番最初に目に入る大きな部分 */
#hero {
    min-height: 90vh;
    display: flex;
    justify-content: center;
    align-items: center;
    text-align: center;
    padding: 100px 20px;
    background: radial-gradient(circle at center, #1a1a2e 0%, #0a0a0c 100%);
}

.hero-content {
    max-width: 800px;
}

#hero h1 {
    font-family: var(--font-heading);
    font-size: 3.5rem;
    margin-bottom: 10px;
    background: linear-gradient(to right, #fff, var(--accent-color));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero-subtitle {
    font-size: 1.2rem;
    color: #a0a0a0;
    margin-bottom: 40px;
}

.hero-image {
    width: 100%;
    max-width: 600px;
    border-radius: 15px;
    box-shadow: 0 0 50px rgba(0, 123, 255, 0.2);
    margin-bottom: 40px;
    transition: transform 0.5s ease;
}

.hero-image:hover {
    transform: scale(1.02);
}

.intro-text {
    font-size: 1.1rem;
    margin-bottom: 40px;
    line-height: 1.8;
}

.cta-button {
    display: inline-block;
    background-color: var(--accent-color);
    color: white;
    text-decoration: none;
    padding: 18px 40px;
    font-size: 1.2rem;
    border-radius: 50px;
    cursor: pointer;
    font-weight: bold;
    box-shadow: 0 10px 20px rgba(0, 123, 255, 0.3);
    transition: all 0.3s ease;
}

.cta-button:hover {
    transform: translateY(-5px);
    box-shadow: 0 15px 30px rgba(0, 123, 255, 0.5);
    background-color: #0056b3;
}