/* #トップ分岐ページ: 2択の背景・レイアウト */
.split-hero {
    position: relative;
    min-height: 100svh;
    display: grid;
    grid-template-rows: 1fr;
    color: #f8fafc;
    background: linear-gradient(90deg, #b31313 0%, #b31313 50%, #0c526d 50%, #0c526d 100%);
    overflow: hidden;
    isolation: isolate;
}

@keyframes button-pulse {
    0% {
        background-color: rgba(0, 0, 0, 0.08);
        border-color: rgba(255, 255, 255, 0.85);
    }

    50% {
        background-color: rgba(0, 0, 0, 0.2);
        border-color: rgba(255, 255, 255, 1);
    }

    100% {
        background-color: rgba(0, 0, 0, 0.08);
        border-color: rgba(255, 255, 255, 0.85);
    }
}

.split-hero::before {
    /* うっすら照明のようなビネット */
    content: "";
    position: absolute;
    inset: 0;
    background: radial-gradient(circle at 50% 20%, rgba(255, 255, 255, 0.12), transparent 42%), radial-gradient(circle at 50% 65%, rgba(0, 0, 0, 0.18), transparent 35%);
    pointer-events: none;
    z-index: 1;
}

.split-hero__copy {
    /* タイトル位置（縦持ちスマホ基準） */
    position: absolute;
    top: 8svh;
    left: 50%;
    transform: translateX(-50%);
    text-align: center;
    z-index: 3;
    text-shadow: var(--text-shadow-lg);
}

.split-hero__title {
    margin: 0;
    font-size: 7vw;
    line-height: 1.25;
    font-weight: 800;
    letter-spacing: 0.03em;
    white-space: nowrap;
}

.split-hero__panels {
    /* 左右の選択領域 */
    display: grid;
    grid-template-columns: repeat(2, 1fr);
    min-height: 100svh;
    position: relative;
    z-index: 2;
}

.split-panel {
    /* パネル全体（ボックス位置はパディングで調整） */
    position: relative;
    display: flex;
    padding: 20svh 0 8svh;
    align-items: flex-start;
    justify-content: center;
    text-decoration: none;
    color: #fff;
    overflow: hidden;
    isolation: isolate;
}

.split-panel::before,
.split-panel::after {
    /* 前面グラデと背面人物の2枚重ね */
    content: "";
    position: absolute;
    inset: 0;
    transition: transform 0.3s ease, opacity 0.3s ease;
}

.split-panel::before {
    background: linear-gradient(135deg, rgba(0, 0, 0, 0.35) 0%, rgba(0, 0, 0, 0.2) 45%, rgba(0, 0, 0, 0.05) 100%);
    z-index: 1;
}

.split-panel::after {
    background-position: center bottom;
    background-repeat: no-repeat;
    background-size: auto 66svh;
    z-index: 0;
}

.split-panel--left::after {
    background-image: url("../assets/images/top/hero-left.webp");
    background-position: center 116%;
}

.split-panel--right::after {
    background-image: url("../assets/images/top/hero-right.webp");
    background-position: center 116%;
}

.split-panel--left {
    /* 赤側の下地 */
    background: linear-gradient(160deg, #c81515 0%, #a30f0f 55%, #7d0e0e 100%);
    box-shadow: inset -0.15rem 0 0.6rem rgba(0, 0, 0, 0.25);
}

.split-panel--right {
    /* 青側の下地 */
    background: linear-gradient(200deg, #0f637f 0%, #0d5267 60%, #0b3f50 100%);
    box-shadow: inset 0.15rem 0 0.6rem rgba(0, 0, 0, 0.25);
}

.split-panel__label {
    /* 選択ボックス本体 */
    position: relative;
    z-index: 2;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 84%;
    max-width: 85vw;
    min-height: 13svh;
    padding: 2svh 2.5vw;
    border: 0.15rem solid rgba(255, 255, 255, 0.85);
    background: rgba(0, 0, 0, 0.08);
    box-shadow: 0 0.75rem 1.75rem rgba(0, 0, 0, 0.25), inset 0 0 0 0.06rem rgba(255, 255, 255, 0.1);
    font-size: 6.5vw;
    line-height: 1.2;
    font-weight: 800;
    text-align: center;
    letter-spacing: 0.03em;
    animation: button-pulse 3s infinite ease-in-out;
}

.split-panel:focus-visible .split-panel__label,
.split-panel:hover .split-panel__label {
    border-color: #fff;
    box-shadow: 0 1rem 2rem rgba(0, 0, 0, 0.32), inset 0 0 0 0.06rem rgba(255, 255, 255, 0.16);
}

.split-panel:hover::before,
.split-panel:focus-visible::before {
    opacity: 0.75;
}

.split-panel:hover::after,
.split-panel:focus-visible::after {
    transform: scale(1.02);
}

@media (orientation: landscape) {

    /* スマホ横持ち時はさらに圧縮・下詰め */
    .split-hero {
        min-height: 100svh;
    }

    .split-hero__copy {
        top: 9svh;
    }

    .split-panel {
        padding: 14svh 0 6svh;
    }

    .split-panel::after {
        background-size: auto 52svh;
        background-position: center 120%;
    }

    .split-panel__label {
        min-height: 9svh;
        font-size: 5.6vw;
    }
}

.split-footer {
    position: absolute;
    bottom: 1.5svh;
    left: 0;
    width: 100%;
    text-align: center;
    color: #fff;
    z-index: 10;
    font-size: 3.5vw;
    opacity: 0.8;
    font-family: var(--font-sans);
}