* {
    box-sizing: border-box;
}

:root {
    --line: rgba(40, 52, 66, 0.12);
    --text: #111827;
    --sub: #5f6f82;
    --accent: #6a85b6;
}

html,
body {
    margin: 0;
    padding: 0;

    width: 100%;
    min-height: 100%;

    background:
            linear-gradient(
                    180deg,
                    #dfe4ea 0%,
                    #eef2f6 100%
            );

    color: var(--text);

    font-family:
            "Yu Mincho",
            "Hiragino Mincho ProN",
            "Hiragino Serif",
            serif;
}

body {
    min-height: 100vh;
    padding: 18px;
}


/* =========================================
   外枠
   ========================================= */

.window {
    width: 100%;
    height: calc(100vh - 36px);
    min-height: calc(100vh - 36px);

    overflow: hidden;

    background:
            rgba(255, 255, 255, 0.45);

    border:
            1px solid
            rgba(255, 255, 255, 0.55);

    border-radius: 16px;

    box-shadow:
            0 16px 50px rgba(40, 52, 66, 0.08),
            inset 0 1px 0 rgba(255, 255, 255, 0.8);

    backdrop-filter: blur(6px);
}


/* =========================================
   レイアウト
   ========================================= */

.layout {
    position: relative;

    display: grid;

    grid-template-columns:
    240px 1fr;

    height: 100%;
    min-height:
            calc(100vh - 36px);
}


/* =========================================
   サイドバー
   ========================================= */

.sidebar {
    position: relative;
    z-index: 4;

    padding: 44px 34px;

    background:
            rgba(255, 255, 255, 0.78);

    border-right:
            1px solid var(--line);
}

.sidebar h1 {
    margin: 26px 0 0;

    color: #202938;

    font-size: 18px;
    font-weight: 500;

    letter-spacing: 0.08em;
}

.brand-divider {
    width: calc(100% + 68px);
    height: 0;
    margin: 47px -34px;

    border-top: 1px solid var(--line);
}


/* =========================================
   ナビ
   ========================================= */

.nav {
    display: flex;
    flex-direction: column;

    gap: 34px;
}

.nav button {
    position: relative;

    width: fit-content;
    padding: 0;

    color: #222f3d;
    background: none;
    border: 0;

    font: inherit;
    font-size: 14px;

    letter-spacing: 0.24em;

    text-align: left;
    white-space: nowrap;
    cursor: pointer;
}

.nav button:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 6px;
}

.nav button.active {
    padding-left: 34px;

    color: #617db0;

    font-weight: 600;
}

.nav button.active::before {
    content: "⚓";

    position: absolute;

    left: 0;
    top: 50%;

    font-size: 13px;
    line-height: 1;

    transform:
            translateY(-50%);
}


/* =========================================
   メイン
   ========================================= */

.hero {
    position: relative;

    min-height: calc(100vh - 36px);

    overflow: hidden;

    isolation: isolate;

    background:
            linear-gradient(
                    180deg,
                    #dce4eb 0%,
                    #edf2f6 36%,
                    #e5eaee 42%,
                    #cad4dd 61%,
                    #7f95a9 100%
            );
}

.page-content {
    height: 100%;
    min-height: calc(100vh - 36px);
    overflow-y: auto;
    overscroll-behavior-y: contain;
}

.page-view[hidden] {
    display: none;
}

.page-panel {
    min-height: inherit;
    padding: 76px clamp(32px, 7vw, 96px);

    background:
            linear-gradient(
                    145deg,
                    #ffffff 0%,
                    #f5f7f9 100%
            );
}

.page-panel h2 {
    margin: 0;

    color: #202938;
    font-size: clamp(30px, 3.8vw, 48px);
    font-weight: 500;
    letter-spacing: 0.12em;
}

.page-lead {
    margin: 28px 0 0;

    color: #344254;
    font-size: clamp(18px, 2vw, 24px);
    letter-spacing: 0.08em;
    line-height: 1.8;
}

.page-copy {
    max-width: 680px;
    margin-top: 52px;

    color: var(--sub);
    font-size: 15px;
    line-height: 2.1;
}

.page-copy p {
    margin: 0 0 18px;
}

.business-list {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 16px;

    max-width: 900px;
    margin: 48px 0 0;
    padding: 0;

    list-style: none;
}

.business-list li {
    min-height: 112px;
    display: flex;
    align-items: center;

    padding: 24px;
    border: 1px solid var(--line);

    background: rgba(255, 255, 255, 0.72);
}

.business-list h3 {
    margin: 0;

    color: #344254;
    font-size: 18px;
    font-weight: 500;
    line-height: 1.7;
    letter-spacing: 0.04em;
}

.philosophy-list {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 16px;

    max-width: 1100px;
    margin-top: 48px;
}

.philosophy-item {
    padding: 28px 24px;
    border-top: 2px solid var(--line);

    background: rgba(255, 255, 255, 0.72);
}

.philosophy-item h3 {
    margin: 0 0 18px;

    color: #344254;
    font-size: 21px;
    font-weight: 500;
    letter-spacing: 0.12em;
}

.philosophy-item p {
    margin: 0;

    color: var(--sub);
    font-size: 14px;
    line-height: 2.1;
}

.info-list {
    max-width: 900px;
    margin: 48px 0 0;

    color: var(--sub);
    font-size: 15px;
    line-height: 1.9;
}

.info-row {
    display: grid;
    grid-template-columns: 150px minmax(0, 1fr);
    gap: 24px;

    padding: 20px 0;
    border-top: 1px solid var(--line);
}

.info-row dt {
    color: #344254;
    font-weight: 600;
}

.info-row dd {
    min-width: 0;
    margin: 0;
}

.info-row dd p {
    margin: 0;
}

.info-row dd p + p {
    margin-top: 6px;
}

.info-row dd ul {
    margin: 0;
    padding-left: 1.4em;
}

.info-row dd ul + p {
    margin-top: 14px;
}


/* 空の光 */

.hero::before {
    content: "";

    position: absolute;
    inset: 0;

    z-index: 0;

    background:

            radial-gradient(
                    circle at 83% 24%,
                    rgba(255, 255, 255, 0.9)
                    0 6%,

                    rgba(255, 255, 255, 0.35)
                    13%,

                    rgba(255, 255, 255, 0)
                    28%
            ),

            linear-gradient(
                    180deg,
                    rgba(255, 255, 255, 0.18)
                    0%,

                    rgba(255, 255, 255, 0.02)
                    40%,

                    rgba(255, 255, 255, 0)
                    100%
            );

    pointer-events: none;
}


/* =========================================
   雲
   ========================================= */

.clouds {
    position: absolute;
    inset: 0;

    z-index: 0;

    opacity: 0.55;

    filter: blur(8px);

    background:

            radial-gradient(
                    ellipse at 70% 16%,
                    rgba(255, 255, 255, 0.58)
                    0 12%,

                    transparent 13%
            ),

            radial-gradient(
                    ellipse at 76% 18%,
                    rgba(255, 255, 255, 0.52)
                    0 10%,

                    transparent 11%
            ),

            radial-gradient(
                    ellipse at 82% 16%,
                    rgba(255, 255, 255, 0.48)
                    0 9%,

                    transparent 10%
            ),

            radial-gradient(
                    ellipse at 63% 14%,
                    rgba(255, 255, 255, 0.25)
                    0 8%,

                    transparent 9%
            ),

            radial-gradient(
                    ellipse at 58% 12%,
                    rgba(255, 255, 255, 0.18)
                    0 6%,

                    transparent 7%
            );
}


/* =========================================
   山
   ========================================= */

.mountains {
    position: absolute;

    left: 0;
    right: 0;
    bottom: calc(46% - 1px);

    height:
            clamp(
                    140px,
                    18vh,
                    250px
            );

    z-index: 0;

    opacity: 0.42;
}

.mountains svg {
    display: block;

    width: 100%;
    height: 100%;
}


/* =========================================
   海
   ========================================= */

.ocean {
    position: absolute;

    left: 0;
    right: 0;
    bottom: 0;

    height: 46%;

    z-index: 0;

    overflow: hidden;

    background:

            linear-gradient(
                    180deg,
                    rgba(255, 255, 255, 0.28)
                    0 1px,

                    transparent 1px
            ),

            linear-gradient(
                    180deg,
                    #8ea0b2 0%,
                    #68809a 30%,
                    #506982 65%,
                    #3f566d 100%
            );
}

.ocean::before,
.ocean::after {
    content: "";

    position: absolute;
    inset: 0;

    opacity: 0.65;
}

.ocean::before {
    background:
            repeating-linear-gradient(
                    -8deg,
                    rgba(255, 255, 255, 0.06) 0 1px,
                    transparent 1px 22px
            );
    -webkit-mask-image:
            repeating-linear-gradient(
                    82deg,
                    #000 0 8px,
                    transparent 8px 18px
            );
    mask-image:
            repeating-linear-gradient(
                    82deg,
                    #000 0 8px,
                    transparent 8px 18px
            );
}

.ocean::after {
    background:
            repeating-linear-gradient(
                    8deg,
                    rgba(255, 255, 255, 0.04) 0 1px,
                    transparent 1px 22px
            );
    -webkit-mask-image:
            repeating-linear-gradient(
                    -82deg,
                    #000 0 8px,
                    transparent 8px 18px
            );
    mask-image:
            repeating-linear-gradient(
                    -82deg,
                    #000 0 8px,
                    transparent 8px 18px
            );
}


/* =========================================
   左側白グラデーション
   ========================================= */

.content-mask {
    position: absolute;

    left: 0;
    top: 0;
    bottom: 0;

    width: 62%;

    z-index: 1;

    background:

            linear-gradient(
                    90deg,

                    rgba(255, 255, 255, 0.96)
                    0%,

                    rgba(255, 255, 255, 0.94)
                    55%,

                    rgba(255, 255, 255, 0.74)
                    82%,

                    rgba(255, 255, 255, 0.15)
                    100%
            );
}


/* =========================================
   メインテキスト
   ========================================= */

.content {
    position: relative;

    z-index: 3;

    min-height: inherit;

    display: flex;
    align-items: center;

    padding-left: 82px;
    padding-right: 40px;
}

.copy-block {
    max-width: 100%;
}

.company-name {
    margin: 0;

    color: #111622;

    font-family: "Palatino Linotype", "Book Antiqua", Palatino, serif;

    font-size:
            clamp(
                    46px,
                    6vw,
                    94px
            );

    font-weight: 500;

    line-height: 1.12;

    letter-spacing: 0.12em;
}

.catch-copy {
    margin-top: 28px;

    color: #1d2330;
    white-space: nowrap;

    font-size:
            clamp(
                    22px,
                    2.2vw,
                    38px
            );

    line-height: 1.8;

    letter-spacing: 0.18em;
}


/* =========================================
   船
   ========================================= */

.ship-wrap {
    position: absolute;

    right: 6%;
    bottom: 13%;

    width:
            min(
                    34.2vw,
                    468px
            );

    z-index: 2;

    opacity: 0.93;

    filter:

            drop-shadow(
                    0 18px 18px
                    rgba(24, 39, 55, 0.12)
            )

            drop-shadow(
                    0 4px 6px
                    rgba(24, 39, 55, 0.12)
            );
}

.ship-wrap svg {
    display: block;

    width: 100%;
    height: auto;
    /* 船体より下に伸びる海面の影をSVGの枠で切らない。 */
    overflow: visible;
}


/* =========================================
   タイル
   ========================================= */

.tiles {
    /* JSもここを参照するため時間の単位はms。画面サイズによらず約2.4秒で完了する。 */
    --tile-duration: 450ms;
    --tile-reveal-duration: 2400ms;

    position: absolute;
    inset: 0;

    z-index: 5;

    pointer-events: none;
}

.tile {
    position: absolute;

    background: #fff;

    will-change: opacity;

    animation:
            tile-reveal
            var(--tile-duration)
            cubic-bezier(0.55, 0.08, 0.35, 1)
            forwards;
}

@keyframes tile-reveal {

    0% {
        opacity: 1;
    }

    82% {
        opacity: 1;
    }

    100% {
        opacity: 0;
    }
}

@media (prefers-reduced-motion: reduce) {

    .tile {
        animation-duration: 1ms;
        animation-delay: 0ms !important;
    }

}


/* =========================================
   レスポンシブ
   ========================================= */

@media (max-width: 980px) {

    .layout {
        grid-template-columns: 1fr;
    }

    .sidebar {
        position: absolute;

        left: 0;
        top: 0;

        width: 100%;
        height: 112px;

        display: flex;
        flex-direction: column;
        align-items: stretch;
        justify-content: center;
        gap: 10px;

        padding: 10px 20px 8px;

        border-right: none;

        border-bottom:
                1px solid var(--line);
    }

    .sidebar h1 {
        margin: 0;
    }

    .brand-divider {
        width: calc(100% + 40px);
        margin: 8px -20px 0;
    }

    .nav {
        flex-direction: row;
        gap: 20px;

        width: 100%;
        overflow-x: auto;
        scrollbar-width: none;
    }

    .nav::-webkit-scrollbar {
        display: none;
    }

    .nav button {
        font-size: 11px;
        letter-spacing: 0.12em;
    }

    .nav button.active {
        padding-left: 17px;
    }

    .content-mask {
        width: 100%;

        background:

                linear-gradient(
                        180deg,

                        rgba(255, 255, 255, 0.92)
                        0%,

                        rgba(255, 255, 255, 0.86)
                        34%,

                        rgba(255, 255, 255, 0.42)
                        66%,

                        rgba(255, 255, 255, 0.1)
                        100%
                );
    }

    .content {
        align-items: flex-start;

        padding:
                150px
                24px
                40px;
    }

    .copy-block {
        margin-top: 40px;
    }

    .page-panel {
        padding: 148px 24px 48px;
    }

    .page-copy {
        margin-top: 36px;
    }

    .business-list {
        grid-template-columns: 1fr;
        gap: 12px;
        margin-top: 32px;
    }

    .business-list li {
        min-height: 80px;
        padding: 18px;
    }

    .philosophy-list {
        grid-template-columns: 1fr;
        gap: 12px;
        margin-top: 32px;
    }

    .philosophy-item {
        padding: 22px 18px;
    }

    .info-list {
        margin-top: 32px;
    }

    .info-row {
        grid-template-columns: 1fr;
        gap: 4px;

        padding: 16px 0;
    }

    .company-name {
        font-size: 44px;
    }

    .catch-copy {
        font-size: clamp(12px, 3.8vw, 22px);
    }

    .ship-wrap {
        right: -4%;
        bottom: 10%;

        width:
                min(
                        61.2vw,
                        378px
                );
    }

}