:root {
    --text-color: #dadada;
    --highlight-color: #ff002d;
    --link-hover-color: #3bcb74;
    --background-blur: 5px;
}

* {
    user-select: none;
    text-decoration: none;
    box-sizing: border-box;
}

body {
    margin: 0;
    background-color: black;
    color: var(--text-color);
    overscroll-behavior: none;
    display: flex;
    flex-direction: column;
    align-items: center;
    font-family: "Noto Sans JP", "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
}

.background, #particles-js {
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    overflow: hidden;
    z-index: -2;
}

#particles-js {
    z-index: -1;
}

.background {
    background: url('https://media.rixray.com/logos/background.avif') center/cover no-repeat;
    filter: brightness(100%);
    touch-action: none;
}

.bottom-tab-bar, .content {
    border: 1px solid rgba(255, 255, 255, 0.15);
    box-shadow: rgba(0, 0, 0, 0.05) -1px -1px 5px 0, rgba(0, 0, 0, 0.15) 0 20px 25px -5px, rgba(0, 0, 0, 0.04) 0 10px 10px -5px;
    backdrop-filter: blur(var(--background-blur));
}

.bottom-tab-bar {
    background-image: linear-gradient(180deg, hsla(0, 0%, 100%, 0), hsl(0deg 0% 80% / 20%));
    position: fixed;
    bottom: 1.5rem;
    left: 50%;
    transform: translateX(-50%);
    z-index: 10;
    display: flex;
    justify-content: center;
    gap: 1rem;
    padding: 0.3rem;
    border-radius: 30px;
    transition: bottom 0.4s ease-out;
}

.bottom-tab-bar.hidden {
    bottom: -100px;
}

.tab-link {
    color: #ffffff;
    padding: 0.6rem;
    border-radius: 40px;
    transition: background-color 0.3s ease, color 0.3s ease;
    display: flex;
    align-items: center;
    white-space: nowrap;
}

.tab-link:hover {
    background-color: rgba(255, 255, 255, 0.1);
    color: #ffffff;
}

.tab-link.active {
    background-color: var(--link-hover-color);
    color: #ffffff;
    cursor: default;
}

.tab-link.active:hover {
    background-color: var(--link-hover-color);
}

.tab-link .icon {
    min-width: 24px;
}

.main-container {
    width: 100%;
    max-width: 1200px;
    padding: 8rem 2rem 4rem;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 3rem;
}

.main-title {
    font-size: clamp(6rem, 12vw, 11rem);
    font-weight: 900;
    text-transform: uppercase;
    text-align: end;
    color: #3bcb74;
    letter-spacing: 0.05em;
    animation: fadeInUp 0.8s ease-out 0.2s forwards;
    opacity: 0;
    text-shadow: 0 -1px 1px rgba(255, 255, 255, 0.15), 0 4px 6px rgba(0, 0, 0, 0.4), 0 10px 20px rgba(0, 0, 0, 0.3);
}

.content-wrapper {
    display: flex;
    justify-content: center;
    align-items: flex-start;
    gap: 2rem;
    width: 100%;
}

.content {
    background-image: linear-gradient(180deg, hsla(0, 0%, 100%, 0), hsl(0deg 0% 100% / 15%));
    flex: 2;
    max-width: 85ch;
    text-shadow: 2px 2px 6px rgba(0, 0, 0, 0.7);
    padding: 2rem;
    border-radius: 1rem;
    backdrop-filter: blur(15px);
}

.content p {
    white-space: pre-line;
    line-break: strict;
    word-break: keep-all;
    overflow-wrap: anywhere;
    font-weight: 500;
    font-size: clamp(1rem, 5vw, 1.5rem);
    line-height: 1.5;
    margin: 0 0 1.5em;
    text-align: center;
}

mark {
    background: linear-gradient(transparent 20%, var(--highlight-color) 100%);
    font-weight: bold;
    color: #ffffff;
}

.main-footer {
    padding: 1rem;
    display: flex;
    gap: 2.5rem;
    justify-content: center;
    align-items: center;
}

.social-link {
    display: block;
    transition: transform 0.3s ease;
}

.social-link:hover {
    transform: scale(1.25) translateY(-3px);
}

@media (max-width: 992px) {
    .content-wrapper {
        flex-direction: column;
        align-items: center;
        gap: 3rem;
    }
    .content {
        max-width: 100%;
        text-align: center;
    }
}

@media (max-width: 768px) {
    .main-container {
        padding: 5rem 0.5rem;
    }
    .content {
        padding: 1rem;
    }
    .tab-link span {
        padding-left: 5px;
        font-size: 0.9rem;
    }
    .main-title {
        writing-mode: vertical-rl;
        text-align: center;
        line-height: 1.2;
        letter-spacing: -3px;
    }
}

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