*, *::before, *::after {
    box-sizing: border-box;
}

:root {
    color-scheme: dark;
    --bg-primary: #0a0e17;
    --bg-secondary: #111827;
    --bg-card: #171e2d;
    --bg-card-strong: #1c2536;
    --text-primary: #f1f5f9;
    --text-secondary: #a4b0c2;
    --text-muted: #748197;
    --accent: #3b82f6;
    --accent-light: #75a7ff;
    --violet: #9b7cf6;
    --green: #4ade80;
    --amber: #fbbf24;
    --border: rgba(148, 163, 184, 0.16);
    --border-strong: rgba(117, 167, 255, 0.34);
    --shadow: 0 24px 70px rgba(0, 0, 0, 0.28);
    --content-width: 50rem;
    --shell-width: 74rem;
    --display-font: "Avenir Next Condensed", "Arial Narrow", "Helvetica Neue", sans-serif;
    --body-font: -apple-system, BlinkMacSystemFont, "SF Pro Text", "Segoe UI", sans-serif;
    --utility-font: "SFMono-Regular", Consolas, "Liberation Mono", monospace;
}

html {
    scroll-behavior: smooth;
    background: var(--bg-primary);
}

body {
    min-width: 20rem;
    margin: 0;
    background:
        radial-gradient(circle at 12% 8%, rgba(59, 130, 246, 0.13), transparent 30rem),
        radial-gradient(circle at 88% 24%, rgba(155, 124, 246, 0.09), transparent 28rem),
        var(--bg-primary);
    color: var(--text-primary);
    font-family: var(--body-font);
    font-size: 1rem;
    line-height: 1.72;
    text-rendering: optimizeLegibility;
}

a {
    color: var(--accent-light);
    text-underline-offset: 0.2em;
    text-decoration-thickness: 0.08em;
}

a:hover {
    color: #a9c8ff;
}

a:focus-visible,
summary:focus-visible {
    border-radius: 0.25rem;
    outline: 3px solid var(--amber);
    outline-offset: 4px;
}

.skip-link {
    position: fixed;
    top: 0.75rem;
    left: 0.75rem;
    z-index: 1000;
    padding: 0.65rem 0.9rem;
    border-radius: 0.45rem;
    background: var(--text-primary);
    color: var(--bg-primary);
    font-weight: 800;
    transform: translateY(-180%);
    transition: transform 150ms ease;
}

.skip-link:focus {
    color: var(--bg-primary);
    transform: translateY(0);
}

.bg-grid {
    position: fixed;
    inset: 0;
    z-index: -1;
    pointer-events: none;
    background-image:
        linear-gradient(rgba(117, 167, 255, 0.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(117, 167, 255, 0.025) 1px, transparent 1px);
    background-size: 4rem 4rem;
    mask-image: linear-gradient(to bottom, black, transparent 82%);
}

.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    border-bottom: 1px solid rgba(117, 167, 255, 0.12);
    background: rgba(10, 14, 23, 0.9);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);
}

.site-nav {
    display: flex;
    width: min(calc(100% - 2rem), var(--shell-width));
    min-height: 4.5rem;
    margin: 0 auto;
    align-items: center;
    justify-content: space-between;
    gap: 1.25rem;
}

.brand {
    flex: 0 0 auto;
    background: linear-gradient(120deg, var(--accent-light), var(--violet));
    background-clip: text;
    color: transparent;
    font-family: var(--display-font);
    font-size: clamp(1.25rem, 3vw, 1.55rem);
    font-weight: 800;
    letter-spacing: -0.025em;
    text-decoration: none;
}

.nav-links {
    display: flex;
    align-items: center;
    justify-content: flex-end;
    gap: clamp(0.7rem, 2vw, 1.35rem);
    font-size: 0.86rem;
    font-weight: 650;
}

.nav-links a {
    color: var(--text-secondary);
    text-decoration: none;
}

.nav-links a:hover {
    color: var(--text-primary);
}

main {
    width: min(calc(100% - 2rem), var(--shell-width));
    margin: 0 auto;
    padding: 2rem 0 5rem;
}

.breadcrumbs {
    max-width: var(--content-width);
    margin: 0 auto 2.5rem;
    color: var(--text-muted);
    font-family: var(--utility-font);
    font-size: 0.76rem;
    letter-spacing: 0.035em;
    text-transform: uppercase;
}

.breadcrumbs ol {
    display: flex;
    flex-wrap: wrap;
    margin: 0;
    padding: 0;
    list-style: none;
}

.breadcrumbs li + li::before {
    margin: 0 0.55rem;
    color: var(--accent);
    content: "/";
}

.breadcrumbs a {
    color: var(--text-secondary);
}

.content-article {
    max-width: var(--content-width);
    margin: 0 auto;
}

.article-header {
    margin-bottom: 4rem;
}

.eyebrow {
    margin: 0 0 0.8rem;
    color: var(--accent-light);
    font-family: var(--utility-font);
    font-size: 0.77rem;
    font-weight: 700;
    letter-spacing: 0.11em;
    text-transform: uppercase;
}

h1,
h2,
h3 {
    color: var(--text-primary);
    font-family: var(--display-font);
    line-height: 1.12;
}

h1 {
    max-width: 18ch;
    margin: 0;
    font-size: clamp(2.65rem, 8vw, 5.4rem);
    font-weight: 800;
    letter-spacing: -0.045em;
}

h2 {
    margin: 0 0 1rem;
    font-size: clamp(1.65rem, 4vw, 2.35rem);
    font-weight: 760;
    letter-spacing: -0.025em;
}

h3 {
    font-size: 1.2rem;
}

p,
li {
    color: var(--text-secondary);
}

.answer {
    position: relative;
    margin: 1.65rem 0 0;
    padding: 1.55rem 1.45rem 1.4rem;
    border: 1px solid var(--border-strong);
    border-radius: 0.8rem;
    background: linear-gradient(135deg, rgba(59, 130, 246, 0.11), rgba(155, 124, 246, 0.055));
    box-shadow: var(--shadow);
    color: var(--text-primary);
    font-size: clamp(1.08rem, 2.2vw, 1.28rem);
    font-weight: 560;
    line-height: 1.58;
}

.answer::before {
    position: absolute;
    top: -2px;
    right: 1.2rem;
    left: 1.2rem;
    height: 3px;
    border-radius: 999px;
    background: repeating-linear-gradient(
        90deg,
        var(--accent) 0 0.32rem,
        transparent 0.32rem 0.95rem,
        var(--violet) 0.95rem 1.12rem,
        transparent 1.12rem 1.9rem
    );
    content: "";
}

.updated {
    margin: 0.8rem 0 0;
    color: var(--text-muted);
    font-family: var(--utility-font);
    font-size: 0.75rem;
    letter-spacing: 0.04em;
    text-transform: uppercase;
}

.lede {
    margin-top: 1.6rem;
    color: var(--text-secondary);
    font-size: 1.06rem;
}

.policy-link {
    margin-top: 1.45rem;
    padding-left: 1rem;
    border-left: 3px solid var(--green);
}

.content-section {
    margin-top: 4rem;
    scroll-margin-top: 6rem;
}

.section-label {
    display: block;
    margin-bottom: 0.65rem;
    color: var(--accent-light);
    font-family: var(--utility-font);
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.09em;
    text-transform: uppercase;
}

.content-section > p {
    margin: 0 0 1rem;
}

.content-section > p:last-child {
    margin-bottom: 0;
}

.guide-video {
    margin: 1.75rem 0;
}

.guide-video-grid {
    display: grid;
    grid-template-columns: repeat(2, minmax(0, 1fr));
    gap: 1.25rem;
    align-items: start;
}

.guide-video-frame {
    overflow: hidden;
    border: 1px solid var(--border);
    border-radius: 0.9rem;
    background: #000000;
    aspect-ratio: 16 / 9;
    box-shadow: 0 18px 45px rgba(0, 0, 0, 0.2);
}

.guide-video-frame.is-portrait {
    width: min(100%, 22rem);
    margin-inline: auto;
    aspect-ratio: 4 / 5;
}

.guide-video-frame iframe {
    display: block;
    width: 100%;
    height: 100%;
    border: 0;
}

.guide-video figcaption {
    margin-top: 0.7rem;
    color: var(--text-muted);
    font-size: 0.88rem;
}

.table-scroll {
    margin: 1.5rem 0;
    overflow-x: auto;
    border: 1px solid var(--border);
    border-radius: 0.85rem;
    background: rgba(23, 30, 45, 0.76);
    box-shadow: 0 18px 45px rgba(0, 0, 0, 0.16);
}

table {
    width: 100%;
    min-width: 43rem;
    border-collapse: collapse;
}

caption {
    padding: 1rem 1.1rem 0.75rem;
    color: var(--text-primary);
    font-family: var(--utility-font);
    font-size: 0.75rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-align: left;
    text-transform: uppercase;
}

th,
td {
    padding: 0.95rem 1.05rem;
    border-top: 1px solid var(--border);
    vertical-align: top;
    text-align: left;
}

th {
    background: rgba(59, 130, 246, 0.07);
    color: var(--text-primary);
    font-family: var(--utility-font);
    font-size: 0.75rem;
    letter-spacing: 0.025em;
}

td {
    color: var(--text-secondary);
    font-size: 0.92rem;
}

tbody th {
    color: var(--accent-light);
}

.mode-token,
.flow-token {
    display: inline-flex;
    align-items: center;
    gap: 0.4rem;
    white-space: nowrap;
}

.mode-token::before,
.flow-token::before {
    width: 0.48rem;
    height: 0.48rem;
    border-radius: 50%;
    background: var(--accent);
    box-shadow: 0 0 0 0.22rem rgba(59, 130, 246, 0.13);
    content: "";
}

.flow-token.apple::before {
    background: var(--violet);
    box-shadow: 0 0 0 0.22rem rgba(155, 124, 246, 0.13);
}

.flow-token.network::before {
    background: var(--amber);
    box-shadow: 0 0 0 0.22rem rgba(251, 191, 36, 0.12);
}

.fact-note {
    margin: 1.4rem 0;
    padding: 1.15rem 1.25rem;
    border-left: 3px solid var(--accent);
    background: rgba(59, 130, 246, 0.07);
    color: var(--text-secondary);
}

.fact-note strong {
    color: var(--text-primary);
}

code {
    padding: 0.08rem 0.28rem;
    border: 1px solid var(--border);
    border-radius: 0.28rem;
    background: rgba(255, 255, 255, 0.035);
    color: #d9e5f7;
    font-family: var(--utility-font);
    font-size: 0.88em;
}

.faq-list {
    display: grid;
    gap: 0.85rem;
    margin-top: 1.4rem;
}

.faq-list details {
    border: 1px solid var(--border);
    border-radius: 0.75rem;
    background: rgba(23, 30, 45, 0.76);
}

.faq-list details[open] {
    border-color: var(--border-strong);
    background: var(--bg-card-strong);
}

.faq-list summary {
    position: relative;
    padding: 1.05rem 3rem 1.05rem 1.15rem;
    color: var(--text-primary);
    cursor: pointer;
    font-family: var(--display-font);
    font-size: 1.15rem;
    font-weight: 720;
    list-style: none;
}

.faq-list summary::-webkit-details-marker {
    display: none;
}

.faq-list summary::after {
    position: absolute;
    top: 50%;
    right: 1.15rem;
    color: var(--accent-light);
    content: "+";
    font-family: var(--utility-font);
    font-size: 1.2rem;
    transform: translateY(-50%);
}

.faq-list details[open] summary::after {
    content: "−";
}

.faq-list details p {
    margin: 0;
    padding: 0 1.15rem 1.15rem;
}

.closing-card {
    margin-top: 4rem;
    padding: clamp(1.3rem, 4vw, 2rem);
    border: 1px solid var(--border-strong);
    border-radius: 0.9rem;
    background:
        linear-gradient(120deg, rgba(59, 130, 246, 0.12), rgba(155, 124, 246, 0.08)),
        var(--bg-card);
}

.closing-card h2 {
    max-width: 24ch;
}

.closing-card p {
    margin: 0 0 1.25rem;
}

.button-link {
    display: inline-flex;
    min-height: 2.8rem;
    padding: 0.7rem 1rem;
    align-items: center;
    border-radius: 0.5rem;
    background: var(--accent);
    color: #ffffff;
    font-weight: 760;
    text-decoration: none;
}

.button-link:hover {
    background: #5795f7;
    color: #ffffff;
}

.site-footer {
    padding: 2.25rem 1rem 2.75rem;
    border-top: 1px solid var(--border);
    text-align: center;
}

.site-footer nav {
    display: flex;
    flex-wrap: wrap;
    justify-content: center;
    gap: 0.6rem 1.2rem;
    margin-bottom: 0.8rem;
    font-size: 0.86rem;
}

.site-footer p {
    margin: 0;
    color: var(--text-muted);
    font-size: 0.78rem;
}

@media (max-width: 48rem) {
    .site-nav {
        padding: 0.8rem 0;
        align-items: flex-start;
    }

    .nav-links {
        flex-wrap: wrap;
        row-gap: 0.45rem;
    }

    main {
        padding-top: 1.4rem;
    }

    .breadcrumbs {
        margin-bottom: 1.8rem;
    }

    .article-header {
        margin-bottom: 3rem;
    }

    .answer {
        padding: 1.3rem 1.1rem 1.2rem;
    }

    .content-section {
        margin-top: 3.25rem;
    }

    .guide-video-grid {
        grid-template-columns: 1fr;
    }
}

@media (max-width: 34rem) {
    .site-nav {
        display: block;
    }

    .brand {
        display: inline-block;
        margin-bottom: 0.7rem;
    }

    .nav-links {
        justify-content: flex-start;
        font-size: 0.82rem;
    }

    h1 {
        font-size: clamp(2.4rem, 13vw, 3.6rem);
    }
}

@media (prefers-reduced-motion: reduce) {
    html {
        scroll-behavior: auto;
    }

    *,
    *::before,
    *::after {
        scroll-behavior: auto !important;
        transition-duration: 0.01ms !important;
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
    }
}

@media print {
    :root {
        color-scheme: light;
    }

    body {
        background: #ffffff;
        color: #111827;
    }

    .site-header,
    .skip-link,
    .bg-grid,
    .closing-card .button-link {
        display: none;
    }

    main,
    .content-article,
    .breadcrumbs {
        width: 100%;
        max-width: none;
    }

    h1,
    h2,
    h3,
    p,
    li,
    td,
    th,
    a {
        color: #111827;
    }

    .answer,
    .table-scroll,
    .faq-list details,
    .closing-card {
        border-color: #cbd5e1;
        background: #ffffff;
        box-shadow: none;
    }
}