/* --- Section 1: Hero (Auto-Kinetic) --- */
#section_1 {
    position: relative;
    width: 100%;
    height: 100vh; /* 画面いっぱいに広げる */
    overflow: hidden;
    background: #000;
}

#top-video-container {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
}

.video-player {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    object-fit: cover;
    opacity: 0;
    transition: opacity 0.5s ease;
}

.video-overlay {
    position: absolute;
    inset: 0;
    width: 100%;
    height: 100%;
    background: rgba(0,0,0,0.5); /* 文字を読みやすくするための暗幕 */
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    z-index: 10;
}

.kinetic-title-container {
    text-align: center;
    color: #fff;
}

.kinetic-title {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.5em; /* 単語間のスペース */
    margin: 0;
    padding: 0;
}

.kinetic-title .word {
    display: inline-flex;
    white-space: nowrap;
}

.kinetic-title span {
    display: inline-block;
    font-size: clamp(3rem, 12vw, 6rem);
    font-weight: 900;
    opacity: 0;
    transform: translateY(30px) scale(0.8);
    transition: opacity 0.8s, transform 0.8s cubic-bezier(0.16, 1, 0.3, 1);
}

.kinetic-title.loaded span {
    opacity: 1;
    transform: translateY(0) scale(1);
}

.hero-subtitle {
    font-family: var(--font-serif);
    font-size: clamp(1.2rem, 3vw, 2rem);
    line-height: 1.8;
    opacity: 0;
    transform: translateY(20px);
    transition: opacity 1s, transform 1s;
    transition-delay: 0.8s; /* タイトルの組み上がりの後に表示 */
}

.hero-subtitle.loaded {
    opacity: 1;
    transform: translateY(0);
}

/* --- Scroll Indicator --- */
.scroll-guide {
    position: absolute;
    bottom: 40px;
    display: flex;
    flex-direction: column;
    align-items: center;
    gap: 10px;
    z-index: 100;
    animation: bounce 2s infinite;
    color: #fff;
}

.scroll-guide span {
    font-family: var(--font-sans);
    font-size: 0.7rem;
    letter-spacing: 0.3em;
    opacity: 0.6;
}

.scroll-line {
    width: 1px;
    height: 60px;
    background: linear-gradient(to bottom, var(--primary), transparent);
}

@keyframes bounce {
    0%, 100% { transform: translateY(0); }
    50% { transform: translateY(10px); }
}