/* ============================================================
   AirReader — Design system: "Brand Blue"
   参照（payn.io）のテイスト — 鮮やかなブランドブルー、ピル型ボタン、
   太い見出し、写真/モックアップ+浮遊チップのヒーロー、濃紺の数値帯 —
   をAirReaderの実際のコピーと機能に合わせて再構成。
   ============================================================ */

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* 見出し用フォント: 自前ホスティング（見出しで実際に使う文字のみのサブセット）
   外部CDNには通信せず、本文は引き続きシステムフォントでオフライン安定性を保つ */
@font-face {
    font-family: 'Zen Kaku Gothic New';
    font-style: normal;
    font-weight: 700;
    font-display: swap;
    src: url('fonts/ZenKakuGothicNew-700.woff2') format('woff2');
}

@font-face {
    font-family: 'Zen Kaku Gothic New';
    font-style: normal;
    font-weight: 900;
    font-display: swap;
    src: url('fonts/ZenKakuGothicNew-900.woff2') format('woff2');
}

:root {
    /* --- color: 鮮やかなブランドブルーを主役に、ネイビーを一箇所だけの濃色アンカー、
       オレンジを控えめな第二アクセントとして使う --- */
    --brand: #0091FE;
    --brand-deep: #0041D1;
    --navy: #09253A;
    --orange: #FE8044;

    --white: #FFFFFF;
    --paper: #FFFFFF;       /* page / section background */
    --paper-tint: #F4F8FD;  /* very light blue-tinted alt section background */
    --line: rgba(11, 15, 25, 0.08);

    --ink: #0B0F19;
    --ink-soft: #5B6472;

    /* text-on-brand: 大きい太字見出し・ボタンのみに使う（本文サイズには使わない） */
    --on-brand: #FFFFFF;
    --on-navy: #FFFFFF;
    --on-navy-soft: rgba(255, 255, 255, 0.68);

    --radius: 24px;
    --radius-sm: 14px;
    --shadow: 0 24px 48px -24px rgba(11, 15, 25, 0.18), 0 8px 16px -8px rgba(11, 15, 25, 0.10);
    --shadow-deep: 0 32px 64px -28px rgba(11, 15, 25, 0.28), 0 12px 24px -12px rgba(11, 15, 25, 0.14);

    --z-skip-link: 100;

    --font-display: 'Zen Kaku Gothic New', -apple-system, 'Hiragino Sans', 'Hiragino Kaku Gothic ProN', sans-serif;
    --font-body: -apple-system, 'Hiragino Kaku Gothic ProN', 'Hiragino Sans', sans-serif;
}

/* このサイトはブランドカラー主体の固定デザイン（参照サイトと同様、OSのダーク
   モードに応じた配色反転は行わない）。本文の読みやすさのみ、わずかに調整する。 */
@media (prefers-color-scheme: dark) {
    :root {
        --ink-soft: #6B7480;
    }
}

html {
    scroll-behavior: smooth;
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }
    *, *::before, *::after {
        animation-duration: 0.001ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.001ms !important;
    }
}

body {
    font-family: var(--font-body);
    background-color: var(--paper);
    color: var(--ink);
    line-height: 1.7;
    -webkit-font-smoothing: antialiased;
}

a {
    color: var(--brand);
}

img {
    max-width: 100%;
}

:focus-visible {
    outline: 3px solid var(--brand-deep);
    outline-offset: 2px;
}

.hero :focus-visible,
.value-band :focus-visible,
.closing :focus-visible {
    outline-color: var(--white);
}

.skip-link {
    position: absolute;
    left: -999px;
    top: 0;
    background: var(--ink);
    color: var(--white);
    padding: 10px 16px;
    z-index: var(--z-skip-link);
}

.skip-link:focus {
    left: 12px;
    top: 12px;
}

.container {
    max-width: 1180px;
    margin: 0 auto;
    padding: 0 24px;
}

.eyebrow {
    font-size: 13px;
    font-weight: 700;
    color: var(--brand);
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-bottom: 10px;
}

.eyebrow--on-brand {
    color: var(--on-navy-soft);
}

h1, h2, h3,
.hero__title, .features__title, .gallery__title, .closing__title {
    text-wrap: balance;
}

p, .hero__lead, .feature-row__text, .page-content p, .faq-a, .closing__lead {
    text-wrap: pretty;
}

/* ============================================================
   ピル型ボタン
   ============================================================ */

.pill {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 15px;
    text-decoration: none;
    padding: 14px 28px;
    border-radius: 999px;
    border: 1.5px solid transparent;
    transition: color 150ms ease-out, background-color 150ms ease-out, border-color 150ms ease-out, box-shadow 150ms ease-out;
}

.pill--outline {
    border-color: var(--brand);
    color: var(--brand);
    background: transparent;
}

.pill--outline:hover,
.pill--outline:focus-visible {
    background: var(--brand);
    color: var(--on-brand);
}

.pill--solid-light {
    background: var(--white);
    color: var(--brand-deep);
    box-shadow: var(--shadow);
}

.pill--solid-light:hover,
.pill--solid-light:focus-visible {
    background: var(--navy);
    color: var(--white);
}

.pill--ghost-light {
    border-color: rgba(255, 255, 255, 0.55);
    color: var(--on-brand);
    background: transparent;
}

.pill--ghost-light:hover,
.pill--ghost-light:focus-visible {
    background: rgba(255, 255, 255, 0.16);
    border-color: var(--white);
}

/* ============================================================
   公開前バナー / ステータス表示
   ============================================================ */

.prelaunch-banner {
    background: var(--navy);
    color: var(--white);
    text-align: center;
    font-size: 13px;
    font-weight: 700;
    padding: 10px 16px;
}

.status-badge {
    display: inline-flex;
    align-items: center;
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 13px;
    color: var(--brand-deep);
    background: rgba(0, 145, 254, 0.10);
    padding: 8px 16px;
    border-radius: 999px;
}

.status-dot {
    width: 7px;
    height: 7px;
    border-radius: 50%;
    background: var(--orange);
    display: inline-block;
    margin-right: 7px;
}

.pill--status {
    cursor: default;
    pointer-events: none;
}

/* ============================================================
   マストヘッド
   ============================================================ */

.masthead {
    background: var(--white);
    border-bottom: 1px solid var(--line);
    padding: 18px 0;
}

.masthead__inner {
    display: flex;
    align-items: center;
    justify-content: space-between;
    flex-wrap: wrap;
    gap: 12px;
}

.masthead__logo {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: 21px;
    color: var(--brand-deep);
    text-decoration: none;
    display: inline-flex;
    align-items: baseline;
    gap: 10px;
}

.masthead__logo span {
    font-family: var(--font-body);
    font-weight: 500;
    font-size: 11px;
    color: var(--ink-soft);
}

.masthead .pill {
    padding: 10px 22px;
    font-size: 14px;
}

.masthead__back {
    font-size: 14px;
    font-weight: 700;
    text-decoration: none;
    color: var(--brand-deep);
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.masthead__back:hover,
.masthead__back:focus-visible {
    color: var(--navy);
}

/* ============================================================
   ヒーロー（index.html のみ）
   ============================================================ */

.hero {
    background: var(--brand);
    padding: 64px 0 56px;
    position: relative;
    overflow: hidden;
}

.hero__inner {
    display: grid;
    grid-template-columns: 1fr 0.85fr;
    align-items: center;
    gap: 40px;
}

.hero__copy {
    display: flex;
    flex-direction: column;
    gap: 22px;
}

.hero__title {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(32px, 4.4vw, 52px);
    line-height: 1.25;
    color: var(--on-brand);
}

.hero__title mark {
    background: none;
    color: var(--orange);
}

.hero__lead {
    font-size: 17px;
    line-height: 1.85;
    color: rgba(255, 255, 255, 0.88);
    max-width: 30em;
}

.hero__actions {
    display: flex;
    gap: 14px;
    flex-wrap: wrap;
    margin-top: 8px;
}

.hero__visual {
    position: relative;
}

.device-placeholder {
    background: var(--navy);
    color: rgba(255, 255, 255, 0.4);
    border-radius: var(--radius);
    box-shadow: var(--shadow-deep);
    display: flex;
    align-items: center;
    justify-content: center;
}

.device-placeholder--hero {
    aspect-ratio: 3 / 4;
    width: 100%;
}

.device-placeholder--hero svg {
    width: 64px;
    height: 64px;
}

.chip {
    position: absolute;
    display: inline-flex;
    align-items: center;
    gap: 8px;
    font-size: 13px;
    font-weight: 700;
    padding: 10px 16px;
    border-radius: 999px;
    box-shadow: var(--shadow);
    white-space: nowrap;
}

.chip svg {
    width: 16px;
    height: 16px;
    flex-shrink: 0;
}

.chip--dark {
    background: var(--navy);
    color: var(--white);
}

.chip--light {
    background: var(--white);
    color: var(--brand-deep);
}

.chip--pos-a {
    top: 14%;
    left: -8%;
}

.chip--pos-b {
    bottom: 12%;
    right: -10%;
}

.hero__scroll {
    position: absolute;
    right: 24px;
    bottom: 18px;
    display: flex;
    align-items: center;
    gap: 6px;
    font-size: 12px;
    font-weight: 700;
    color: rgba(255, 255, 255, 0.65);
}

/* ============================================================
   4つの特徴（交互レイアウト）
   ============================================================ */

.features {
    background: var(--paper);
    padding: 88px 0;
}

.features__head {
    text-align: center;
    margin-bottom: 56px;
}

.features__head .eyebrow {
    justify-content: center;
}

.features__title {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(24px, 3vw, 32px);
    color: var(--ink);
}

.features__sub {
    margin-top: 10px;
    font-size: 15px;
    color: var(--ink-soft);
}

.features__list {
    display: flex;
    flex-direction: column;
    gap: 72px;
}

.feature-row {
    display: grid;
    grid-template-columns: 0.85fr 1fr;
    align-items: center;
    gap: 48px;
}

.feature-row--reverse {
    grid-template-columns: 1fr 0.85fr;
}

.feature-row--reverse .device-placeholder {
    order: 2;
}

.device-placeholder--row {
    aspect-ratio: 4 / 3;
}

.device-placeholder--row svg {
    width: 48px;
    height: 48px;
}

.device-placeholder--brand {
    background: var(--brand);
    color: rgba(255, 255, 255, 0.55);
}

.device-placeholder--navy {
    background: var(--navy);
    color: rgba(255, 255, 255, 0.4);
}

.device-placeholder--orange {
    background: var(--orange);
    color: rgba(255, 255, 255, 0.55);
}

.feature-row__title {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: 22px;
    color: var(--ink);
    margin-bottom: 12px;
}

.feature-row__text {
    font-size: 15px;
    line-height: 1.85;
    color: var(--ink-soft);
    max-width: 32em;
}

.feature-row__note {
    margin-top: 12px;
    font-size: 12.5px;
    line-height: 1.7;
    color: var(--ink-soft);
}

.feature-row__note .note-mark {
    font-weight: 700;
    color: var(--brand);
}

/* ============================================================
   価値の数値帯（濃紺アンカー）
   ============================================================ */

.value-band {
    position: relative;
    background: var(--navy);
    padding: 88px 0;
    overflow: hidden;
}

.value-band__watermark {
    position: absolute;
    top: 50%;
    left: 50%;
    transform: translate(-50%, -50%);
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(80px, 16vw, 220px);
    color: rgba(255, 255, 255, 0.04);
    white-space: nowrap;
    line-height: 1;
    pointer-events: none;
}

.value-band__inner {
    position: relative;
    text-align: center;
}

.value-band__grid {
    margin-top: 32px;
    display: grid;
    grid-template-columns: repeat(3, 1fr);
    gap: 32px;
}

.value-tile {
    text-align: left;
    padding: 28px;
    border-radius: var(--radius-sm);
    background: rgba(255, 255, 255, 0.04);
    border: 1px solid rgba(255, 255, 255, 0.08);
}

.value-tile__icon {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    width: 36px;
    height: 36px;
    border-radius: 10px;
    margin-bottom: 18px;
}

.value-tile__icon svg {
    width: 20px;
    height: 20px;
}

.value-tile__icon--brand {
    background: rgba(0, 145, 254, 0.18);
    color: var(--brand);
}

.value-tile__icon--orange {
    background: rgba(254, 128, 68, 0.18);
    color: var(--orange);
}

.value-tile__num {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: 26px;
    color: var(--on-navy);
}

.value-tile__label {
    margin-top: 8px;
    font-size: 13.5px;
    line-height: 1.7;
    color: var(--on-navy-soft);
}

/* ============================================================
   アプリ画面
   ============================================================ */

.gallery {
    background: var(--paper-tint);
    padding: 88px 0;
}

.gallery__head {
    text-align: center;
    margin-bottom: 40px;
}

.gallery__head .eyebrow {
    justify-content: center;
}

.gallery__title {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(24px, 3vw, 32px);
    color: var(--ink);
}

.gallery__sub {
    margin-top: 10px;
    font-size: 15px;
    color: var(--ink-soft);
}

.gallery__grid {
    display: grid;
    grid-template-columns: repeat(6, 1fr);
    align-items: start;
    gap: 24px 20px;
}

.gallery__credit {
    margin-top: 28px;
    font-size: 12px;
    line-height: 1.6;
    color: var(--ink-soft);
    text-align: center;
}

.float-card {
    position: relative;
    grid-column: span 2;
    background: var(--white);
    border-radius: var(--radius-sm);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.float-card img {
    display: block;
    width: 100%;
    height: auto;
}

.float-card__tag {
    position: absolute;
    bottom: 12px;
    left: 12px;
    padding: 4px 12px;
    background: var(--brand);
    color: var(--white);
    font-size: 11px;
    font-weight: 700;
    border-radius: 999px;
}

/* ============================================================
   フッター（closing band）
   ============================================================ */

.closing {
    background: var(--brand);
    color: var(--on-brand);
    padding: 88px 0 40px;
    text-align: center;
}

.closing__title {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(24px, 3vw, 32px);
}

.closing__lead {
    margin-top: 12px;
    font-size: 15px;
    color: rgba(255, 255, 255, 0.85);
}

.closing .pill {
    margin-top: 28px;
}

.cache-bar {
    max-width: 280px;
    margin: 36px auto 0;
}

.cache-bar__track {
    height: 3px;
    border-radius: 999px;
    background: rgba(255, 255, 255, 0.25);
    overflow: hidden;
}

.cache-bar__fill {
    height: 100%;
    width: 100%;
    border-radius: 999px;
    background: var(--orange);
    transform-origin: left;
    transition: transform 900ms ease-out;
}

.cache-bar.is-visible .cache-bar__fill {
    transform: scaleX(0.08);
}

.cache-bar__caption {
    margin-top: 10px;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.75);
}

.closing__links {
    margin-top: 36px;
    display: flex;
    justify-content: center;
    gap: 10px;
    flex-wrap: wrap;
    font-size: 13px;
}

.closing__links a,
.closing__links .link-button {
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
    border-bottom: 1px solid transparent;
    transition: color 150ms ease-out, border-color 150ms ease-out;
}

.closing__links a:hover,
.closing__links a:focus-visible,
.closing__links .link-button:hover,
.closing__links .link-button:focus-visible {
    color: var(--white);
    border-bottom-color: currentColor;
}

/* ボタン要素をリンクのように見せる（メールアドレスを静的HTMLに残さないための仕組み） */
.link-button {
    background: none;
    border: none;
    padding: 0;
    margin: 0;
    font: inherit;
    cursor: pointer;
    display: inline;
}

.closing__divider {
    color: rgba(255, 255, 255, 0.4);
}

.closing__copyright {
    margin-top: 28px;
    font-size: 12px;
    color: rgba(255, 255, 255, 0.6);
}

/* ============================================================
   サブページ共通（サポート / プライバシーポリシー）
   ============================================================ */

.page-content {
    max-width: 760px;
    margin: 0 auto;
    padding: 56px 24px 80px;
}

.page-content h1 {
    font-family: var(--font-display);
    font-weight: 900;
    font-size: clamp(26px, 3.4vw, 34px);
    color: var(--ink);
}

.page-content > p.page-lede {
    margin-top: 12px;
    color: var(--ink-soft);
    font-size: 15px;
}

.page-content h2 {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 21px;
    color: var(--ink);
    margin-top: 48px;
    margin-bottom: 18px;
    padding-bottom: 12px;
    border-bottom: 1px solid var(--line);
}

.page-content h3 {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 16px;
    color: var(--ink);
    margin-top: 22px;
    margin-bottom: 10px;
}

.page-content p {
    margin-bottom: 14px;
    line-height: 1.85;
    color: var(--ink-soft);
    font-size: 14.5px;
}

.page-content ul {
    margin-bottom: 14px;
    padding-left: 22px;
}

.page-content li {
    margin-bottom: 8px;
    line-height: 1.85;
    color: var(--ink-soft);
    font-size: 14.5px;
}

.page-content strong {
    color: var(--ink);
}

.page-content a,
.page-content .link-button {
    color: var(--brand-deep);
    text-decoration: underline;
    text-decoration-color: rgba(0, 65, 209, 0.3);
}

.page-meta {
    font-size: 13px;
    color: var(--ink-soft);
    margin-top: 4px;
}

.faq-item {
    background: var(--white);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    padding: 24px 26px;
    margin-bottom: 16px;
}

.faq-q {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 16px;
    color: var(--ink);
    margin-bottom: 10px;
    display: flex;
    gap: 10px;
}

.faq-q .faq-tag {
    color: var(--brand-deep);
    flex-shrink: 0;
}

.faq-a {
    color: var(--ink-soft);
    line-height: 1.85;
    font-size: 14.5px;
}

.faq-a ul {
    margin-top: 10px;
    padding-left: 20px;
}

.faq-a li {
    color: var(--ink-soft);
    font-size: 14.5px;
    line-height: 1.85;
    margin-bottom: 6px;
}

.contact-box {
    background: var(--navy);
    color: var(--on-navy);
    border-radius: var(--radius);
    padding: 36px 28px;
    margin-top: 48px;
    text-align: center;
}

.contact-box h3 {
    font-family: var(--font-display);
    font-weight: 700;
    font-size: 18px;
    color: var(--on-navy);
}

.contact-box p {
    color: var(--on-navy-soft);
    font-size: 14px;
    margin-top: 10px;
    margin-bottom: 0;
}

.contact-box .pill {
    margin-top: 20px;
    background: var(--white);
    color: var(--navy);
}

.contact-box .pill:hover,
.contact-box .pill:focus-visible {
    background: var(--orange);
    color: var(--white);
}

.contact-box .contact-email {
    display: block;
    margin-top: 14px;
    font-size: 13px;
    color: rgba(255, 255, 255, 0.55);
}

.back-link {
    display: inline-flex;
    align-items: center;
    gap: 6px;
    margin-top: 56px;
    padding-top: 28px;
    border-top: 1px solid var(--line);
    width: 100%;
    color: var(--ink-soft);
    text-decoration: none;
    font-size: 14px;
    transition: color 150ms ease-out;
}

.back-link:hover,
.back-link:focus-visible {
    color: var(--brand-deep);
}

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

@media (max-width: 900px) {
    .hero__inner {
        grid-template-columns: 1fr;
    }

    .hero__visual {
        max-width: 320px;
        margin: 0 auto;
    }

    .feature-row,
    .feature-row--reverse {
        grid-template-columns: 1fr;
        gap: 28px;
    }

    .feature-row--reverse .device-placeholder {
        order: 0;
    }

    .device-placeholder--row {
        max-width: 360px;
        margin: 0 auto;
    }

    .value-band__grid {
        grid-template-columns: 1fr;
        gap: 16px;
    }

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

    .float-card {
        grid-column: span 1;
    }
}

@media (max-width: 620px) {
    .hero {
        padding: 48px 0 64px;
    }

    .hero__title {
        font-size: 30px;
    }

    .chip {
        font-size: 12px;
        padding: 8px 12px;
    }

    .chip--pos-a {
        left: 4%;
    }

    .chip--pos-b {
        right: 4%;
    }

    .hero__scroll {
        display: none;
    }

    .features,
    .value-band,
    .gallery {
        padding: 64px 0;
    }

    .closing {
        padding: 64px 0 32px;
    }

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

@media (max-width: 480px) {
    .container,
    .features__head,
    .gallery__head {
        padding-left: 18px;
        padding-right: 18px;
    }

    .page-content {
        padding: 40px 18px 60px;
    }
}