:root {
    --bg: #f3f2ee;
    --panel: #ffffff;
    --panel-soft: #f8f7f4;
    --line: #d7d4cd;
    --line-strong: #b9b5ae;
    --text: #171717;
    --muted: #68655f;
    --muted-strong: #4f4c46;
    --accent: #111111;
    --shadow: 0 1px 0 rgba(17, 17, 17, 0.04);
    --radius-lg: 28px;
    --radius-md: 20px;
    --radius-sm: 14px;
}

* {
    box-sizing: border-box;
}

html {
    scroll-behavior: smooth;
}

body {
    margin: 0;
    font-family: "Hiragino Sans", "Yu Gothic", "Noto Sans JP", sans-serif;
    color: var(--text);
    background:
        linear-gradient(180deg, #f7f6f2 0%, #f1f0ec 100%);
}

a {
    color: inherit;
}

img {
    display: block;
    max-width: 100%;
}

.site-shell {
    width: min(1180px, calc(100% - 32px));
    margin: 0 auto;
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 30;
    backdrop-filter: blur(12px);
    background: rgba(243, 242, 238, 0.88);
    border-bottom: 1px solid rgba(185, 181, 174, 0.55);
}

.site-header__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 20px;
    padding: 18px 0;
}

.brand {
    display: flex;
    align-items: center;
    gap: 14px;
    text-decoration: none;
}

.brand__mark {
    width: 42px;
    height: 42px;
    display: grid;
    place-items: center;
    border-radius: 12px;
    background: var(--accent);
    color: #fff;
    font-size: 13px;
    font-weight: 800;
    letter-spacing: 0.08em;
}

.brand__mark img {
    width: 100%;
    height: 100%;
    display: block;
    border-radius: 12px;
}

.brand__text strong {
    display: block;
    font-size: 18px;
    letter-spacing: 0.01em;
}

.brand__text span {
    display: block;
    margin-top: 3px;
    color: var(--muted);
    font-size: 12px;
}

.nav-links {
    display: flex;
    flex-wrap: wrap;
    justify-content: flex-end;
    gap: 10px;
}

.nav-links a,
.button-link {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    min-height: 42px;
    padding: 0 18px;
    border: 1px solid var(--line);
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.7);
    text-decoration: none;
    color: var(--muted-strong);
    font-size: 14px;
    font-weight: 600;
}

.button-link--primary {
    background: var(--accent);
    color: #fff;
    border-color: var(--accent);
}

.button-link--google {
    background: #fff;
    color: #1f1f1f;
    border-color: #dadce0;
}

.button-link--ghost {
    background: transparent;
}

.hero {
    display: grid;
    grid-template-columns: 1.05fr 0.95fr;
    gap: 28px;
    padding: 40px 0 28px;
}

.hero-card,
.panel,
.callout,
.step-card,
.screen-card,
.summary-card {
    background: var(--panel);
    border: 1px solid var(--line);
    border-radius: var(--radius-lg);
    box-shadow: var(--shadow);
}

.hero-card {
    padding: 34px;
}

.eyebrow {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    min-height: 34px;
    padding: 0 14px;
    border-radius: 999px;
    background: var(--panel-soft);
    color: var(--muted-strong);
    font-size: 12px;
    font-weight: 700;
    letter-spacing: 0.08em;
}

.hero h1,
.page-header h1 {
    margin: 18px 0 16px;
    font-size: clamp(34px, 4vw, 58px);
    line-height: 1.08;
    letter-spacing: -0.03em;
}

.hero p,
.page-header p,
.section-head p,
.screen-copy p,
.panel p,
.callout p {
    color: var(--muted);
    line-height: 1.8;
}

.hero-actions {
    display: flex;
    flex-wrap: wrap;
    gap: 12px;
    margin-top: 28px;
}

.hero-metrics {
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 14px;
    margin-top: 28px;
}

.hero-metrics div,
.mini-stat {
    padding: 18px;
    border: 1px solid var(--line);
    border-radius: var(--radius-md);
    background: var(--panel-soft);
}

.hero-metrics strong,
.mini-stat strong {
    display: block;
    font-size: 28px;
    line-height: 1;
}

.hero-metrics span,
.mini-stat span {
    display: block;
    margin-top: 8px;
    color: var(--muted);
    font-size: 12px;
}

.stack {
    display: grid;
    gap: 18px;
}

.section {
    padding: 28px 0;
}

.section-head {
    max-width: 760px;
    margin-bottom: 22px;
}

.section-head h2 {
    margin: 0 0 10px;
    font-size: clamp(24px, 3vw, 38px);
    line-height: 1.2;
    letter-spacing: -0.02em;
}

.cards-3,
.cards-2,
.manual-grid,
.flow-grid,
.screen-grid {
    display: grid;
    gap: 18px;
}

.cards-3 {
    grid-template-columns: repeat(3, minmax(0, 1fr));
}

.cards-2,
.flow-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.screen-grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
}

.manual-grid {
    grid-template-columns: minmax(0, 0.88fr) minmax(340px, 0.82fr);
    align-items: start;
}

.panel,
.callout,
.step-card,
.screen-card,
.summary-card {
    padding: 24px;
}

.panel h3,
.callout h3,
.step-card h3,
.screen-card h3,
.summary-card h3 {
    margin: 0 0 10px;
    font-size: 20px;
    line-height: 1.35;
}

.panel ul,
.callout ul,
.step-card ul,
.screen-copy ul,
.summary-card ul {
    margin: 12px 0 0;
    padding-left: 18px;
    color: var(--muted-strong);
    line-height: 1.8;
}

.screen-copy .meta {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin: 14px 0 0;
}

.chip {
    display: inline-flex;
    align-items: center;
    min-height: 30px;
    padding: 0 12px;
    border-radius: 999px;
    border: 1px solid var(--line);
    background: var(--panel-soft);
    color: var(--muted-strong);
    font-size: 12px;
    font-weight: 700;
}

.shot {
    position: relative;
    width: min(100%, 410px);
    margin: 0 auto;
    border-radius: 26px;
    overflow: hidden;
    border: 1px solid var(--line);
    background: #fff;
    box-shadow: 0 14px 32px rgba(17, 17, 17, 0.08);
}

.shot--wide {
    width: min(100%, 860px);
}

.shot img {
    width: 100%;
    height: auto;
}

.mask {
    position: absolute;
    border-radius: 999px;
    background: rgba(243, 242, 238, 0.98);
    border: 1px solid rgba(185, 181, 174, 0.95);
    box-shadow: 0 4px 14px rgba(17, 17, 17, 0.08);
}

.mask--rect {
    border-radius: 12px;
}

.caption {
    margin-top: 12px;
    color: var(--muted);
    font-size: 13px;
    text-align: center;
    line-height: 1.7;
}

.page-header {
    padding: 34px 0 12px;
}

.toc {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    margin-top: 22px;
}

.toc a {
    text-decoration: none;
}

.footer {
    padding: 40px 0 56px;
    color: var(--muted);
    font-size: 13px;
}

@media (max-width: 980px) {
    .hero,
    .manual-grid,
    .cards-3,
    .cards-2,
    .flow-grid,
    .screen-grid {
        grid-template-columns: 1fr;
    }

    .hero-card,
    .panel,
    .callout,
    .step-card,
    .screen-card,
    .summary-card {
        padding: 22px;
    }
}

@media (max-width: 720px) {
    .site-shell {
        width: min(100% - 20px, 1180px);
    }

    .site-header__inner {
        align-items: flex-start;
        flex-direction: column;
    }

    .nav-links {
        justify-content: flex-start;
    }

    .hero {
        padding-top: 26px;
    }

    .hero-card {
        padding: 24px;
    }

    .hero h1,
    .page-header h1 {
        font-size: 34px;
    }

    .hero-metrics {
        grid-template-columns: 1fr;
    }
}