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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', Meiryo, sans-serif;
    background: #1a1a1a;
    color: #e0e0e0;
    line-height: 1.7;
}

header {
    background: #202020;
    padding: 1rem;
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 2px solid #2d5f3f;
}

.header-container {
    max-width: 1200px;
    margin: 0 auto;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.site-title {
    font-size: 1.5rem;
    font-weight: 600;
    color: #5fd68a;
}

.hamburger {
    background: none;
    border: none;
    cursor: pointer;
    padding: 0.5rem;
}

.hamburger span {
    display: block;
    width: 25px;
    height: 3px;
    background: #5fd68a;
    margin: 5px 0;
    transition: 0.3s;
    border-radius: 2px;
}

.hamburger.active span:nth-child(1) {
    transform: rotate(-45deg) translate(-5px, 6px);
}

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

.hamburger.active span:nth-child(3) {
    transform: rotate(45deg) translate(-5px, -6px);
}

nav {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: #252525;
    transition: 0.3s;
    padding-top: 80px;
    box-shadow: -4px 0 12px rgba(0, 0, 0, 0.5);
    z-index: 99;
}

nav.active {
    right: 0;
}

nav a {
    display: block;
    padding: 1.2rem 2rem;
    color: #e0e0e0;
    text-decoration: none;
    border-bottom: 1px solid #333;
    transition: 0.2s;
}

nav a:hover {
    background: #2d5f3f;
    color: #5fd68a;
}

.overlay {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    background: rgba(0, 0, 0, 0.7);
    z-index: 50;
}

.overlay.active {
    display: block;
}

main {
    max-width: 900px;
    margin: 0 auto;
    padding: 2rem 1rem;
}

section {
    padding-top: 1rem;
    margin-bottom: 3rem;
}

section:target {
    scroll-margin-top: 80px;
}

h1 {
    color: #5fd68a;
    font-size: 2rem;
    margin-bottom: 1.5rem;
    border-bottom: 3px solid #2d5f3f;
    padding-bottom: 0.5rem;
}

h2 {
    color: #6ee09a;
    font-size: 1.4rem;
    margin: 2rem 0 1rem;
}

p {
    margin-bottom: 1rem;
    color: #c0c0c0;
}

.profile-section {
    background: #242424;
    padding: 2rem;
    border-radius: 8px;
    border-left: 4px solid #5fd68a;
    margin-bottom: 2rem;
}

.profile-section p {
    margin-bottom: 0.8rem;
}

.contact-info {
    margin-top: 1.5rem;
    padding-top: 1.5rem;
    border-top: 1px solid #333;
    color: #b0b0b0;
}

.rules-section {
    background: #242424;
    padding: 2rem;
    border-radius: 8px;
    margin-bottom: 1.5rem;
}

.rules-section h3 {
    color: #5fd68a;
    font-size: 1.2rem;
    margin-bottom: 1rem;
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.rules-section h3::before {
    content: "▶";
    color: #6ee09a;
}

.rules-section ul {
    list-style: none;
    padding-left: 1.5rem;
}

.rules-section li {
    margin-bottom: 0.6rem;
    color: #c0c0c0;
    position: relative;
}

.rules-section li::before {
    content: "・";
    position: absolute;
    left: -1rem;
    color: #5fd68a;
}

.video-container {
    position: relative;
    padding-bottom: 56.25%;
    height: 0;
    overflow: hidden;
    border-radius: 8px;
    background: #000;
}

.video-container iframe {
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 100%;
    border: none;
}

footer {
    background: #202020;
    text-align: center;
    padding: 1.5rem;
    margin-top: 4rem;
    border-top: 2px solid #2d5f3f;
    color: #888;
    font-size: 0.9rem;
}

@media (min-width: 768px) {
    main {
        padding: 3rem 2rem;
    }

    h1 {
        font-size: 2.5rem;
    }

    .profile-section {
        padding: 2.5rem;
    }
}