:root {
    --bg: #0b0d10;
    --bg-soft: #14171c;
    --bg-card: #181c22;
    --line: #262b33;
    --text: #e8ebf0;
    --text-dim: #9aa3af;
    --accent: #ff6a2c;
    --accent-soft: #ffe7d9;
    --good: #4ade80;
    --warn: #fbbf24;
    --bad: #f87171;
    --code-bg: #0f1216;
    --radius: 10px;
    --maxw: 1100px;
    --maxw-read: 720px;
    --font-sans: ui-sans-serif, system-ui, -apple-system, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    --font-mono: ui-monospace, SFMono-Regular, "SF Mono", Menlo, Consolas, monospace;
}

@media (prefers-color-scheme: light) {
    :root {
        --bg: #fafaf8;
        --bg-soft: #f1f0eb;
        --bg-card: #ffffff;
        --line: #e4e2dc;
        --text: #1a1d22;
        --text-dim: #5b6470;
        --accent: #e8542b;
        --accent-soft: #fff1ea;
        --code-bg: #f4f3ee;
    }
}

* { box-sizing: border-box; }
html { -webkit-text-size-adjust: 100%; }

/* Skip-to-content link — visible only when focused */
.skip {
    position: absolute;
    top: -42px;
    left: .8rem;
    z-index: 100;
    background: var(--accent);
    color: #fff;
    padding: .55rem 1rem;
    border-radius: 0 0 var(--radius) var(--radius);
    font-weight: 600;
    text-decoration: none;
    transition: top .15s;
}
.skip:focus { top: 0; outline: 0; text-decoration: none; }

/* Visible focus styles — keyboard users only via :focus-visible */
:focus-visible {
    outline: 2px solid var(--accent);
    outline-offset: 2px;
    border-radius: 4px;
}
button:focus-visible,
.btn:focus-visible {
    outline-offset: 3px;
}
input:focus-visible {
    outline: none; /* the input already has its own focus glow */
}

/* Honor users who prefer less motion */
@media (prefers-reduced-motion: reduce) {
    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}
body {
    margin: 0;
    background: var(--bg);
    color: var(--text);
    font-family: var(--font-sans);
    font-size: 16.5px;
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}
img, svg { max-width: 100%; display: block; }
a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }
h1, h2, h3, h4 { color: var(--text); line-height: 1.2; letter-spacing: -0.01em; }
h1 { font-size: clamp(2rem, 4.5vw, 3.4rem); margin: 0 0 .8rem; letter-spacing: -0.025em; }
h2 { font-size: clamp(1.4rem, 2.6vw, 2rem); margin: 2.4rem 0 .6rem; letter-spacing: -0.02em; }
h3 { font-size: 1.15rem; margin: 1.8rem 0 .3rem; }
p { margin: 0 0 1rem; }
small, .small { font-size: .87rem; color: var(--text-dim); }
hr { border: 0; border-top: 1px solid var(--line); margin: 2.5rem 0; }
code {
    font-family: var(--font-mono);
    font-size: .92em;
    background: var(--code-bg);
    border: 1px solid var(--line);
    padding: .12em .42em;
    border-radius: 5px;
}
pre {
    background: var(--code-bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 1rem 1.1rem;
    overflow-x: auto;
    font-size: .9rem;
    line-height: 1.55;
}
pre code { border: 0; background: transparent; padding: 0; }
blockquote {
    border-left: 3px solid var(--accent);
    padding: .1rem 1rem;
    margin: 1rem 0;
    color: var(--text-dim);
    background: var(--bg-soft);
    border-radius: 0 var(--radius) var(--radius) 0;
}
table { border-collapse: collapse; width: 100%; margin: 1.2rem 0; }
th, td { padding: .55rem .8rem; border-bottom: 1px solid var(--line); text-align: left; vertical-align: top; }
th { color: var(--text-dim); font-weight: 600; font-size: .88rem; text-transform: uppercase; letter-spacing: .04em; }
ul, ol { padding-left: 1.4rem; margin: 0 0 1rem; }
li { margin-bottom: .25rem; }

/* layout */
.wrap { max-width: var(--maxw); margin: 0 auto; padding: 0 1.2rem; }
.read { max-width: var(--maxw-read); margin: 0 auto; padding: 0 1.2rem; }

/* header */
.site-header {
    border-bottom: 1px solid var(--line);
    background: color-mix(in srgb, var(--bg) 92%, transparent);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 50;
}
.site-header .wrap {
    display: flex;
    align-items: center;
    gap: 1.5rem;
    height: 56px;
}
.brand {
    font-weight: 700;
    color: var(--text);
    letter-spacing: -.01em;
    display: flex;
    align-items: center;
    gap: .55rem;
}
.brand:hover { text-decoration: none; }
.brand .dot { width: 10px; height: 10px; border-radius: 50%; background: var(--accent); display: inline-block; }
.nav { margin-left: auto; display: flex; gap: 1.4rem; align-items: center; }
.nav a { color: var(--text-dim); font-size: .95rem; }
.nav a:hover { color: var(--text); text-decoration: none; }
.nav .btn { padding: .42rem .9rem; font-size: .9rem; }

/* buttons */
.btn {
    display: inline-flex;
    align-items: center;
    gap: .45rem;
    padding: .8rem 1.3rem;
    background: var(--accent);
    color: #fff;
    border: 0;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 1rem;
    cursor: pointer;
    transition: transform .07s ease, filter .15s ease;
}
.btn:hover { filter: brightness(1.08); text-decoration: none; }
.btn:active { transform: translateY(1px); }
.btn.secondary { background: transparent; color: var(--text); border: 1px solid var(--line); }
.btn.secondary:hover { background: var(--bg-soft); }
.btn.ghost { background: transparent; color: var(--accent); padding: .4rem .6rem; }

/* hero */
.hero { padding: 4.5rem 0 3rem; text-align: center; }
.hero h1 { max-width: 18ch; margin-left: auto; margin-right: auto; }
.hero .lede { font-size: 1.15rem; color: var(--text-dim); max-width: 60ch; margin: .8rem auto 1.6rem; }
.hero .cta-row { display: flex; gap: .8rem; justify-content: center; flex-wrap: wrap; margin-top: 1.4rem; }
.hero .badge { display: inline-flex; gap: .4rem; align-items: center; background: var(--bg-soft); border: 1px solid var(--line); border-radius: 99px; padding: .3rem .8rem; font-size: .82rem; color: var(--text-dim); margin-bottom: 1.2rem; }
.hero .badge .pulse { width: 7px; height: 7px; border-radius: 50%; background: var(--good); box-shadow: 0 0 0 0 currentColor; animation: pulse 2s infinite; }
@keyframes pulse {
    0% { box-shadow: 0 0 0 0 color-mix(in srgb, var(--good) 70%, transparent); }
    70% { box-shadow: 0 0 0 8px transparent; }
    100% { box-shadow: 0 0 0 0 transparent; }
}

/* cards */
.grid { display: grid; gap: 1rem; grid-template-columns: repeat(auto-fit, minmax(240px, 1fr)); }
.card {
    background: var(--bg-card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 1.2rem 1.3rem;
}
.card h3 { margin: .1rem 0 .35rem; font-size: 1.05rem; }
.card p { margin: 0; color: var(--text-dim); font-size: .95rem; }
.card .num { color: var(--accent); font-weight: 700; font-size: .85rem; letter-spacing: .06em; }

/* section labels */
.section { padding: 3.5rem 0; }
.section-label { color: var(--accent); font-size: .8rem; letter-spacing: .15em; text-transform: uppercase; font-weight: 600; }
.section h2 { margin-top: .4rem; }
.section.alt { background: var(--bg-soft); }
.section .lede { color: var(--text-dim); max-width: 60ch; margin-bottom: 1.6rem; }

/* module list */
.module-list { display: grid; gap: .6rem; margin: 1.5rem 0; }
.module-list a {
    display: flex;
    gap: 1rem;
    align-items: baseline;
    background: var(--bg-card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: 1rem 1.2rem;
    color: var(--text);
}
.module-list a:hover { border-color: var(--accent); text-decoration: none; }
.module-list .mid { color: var(--text-dim); font-family: var(--font-mono); font-size: .85rem; min-width: 3.5rem; }
.module-list .title { font-weight: 600; flex: 1; }
.module-list .meta { color: var(--text-dim); font-size: .85rem; }

/* breadcrumb */
.crumb { color: var(--text-dim); font-size: .9rem; margin: 1.4rem 0 .4rem; }
.crumb a { color: var(--text-dim); }

/* lesson page */
.lesson { padding: 2rem 0 4rem; }
.lesson h1 { font-size: 2.2rem; }
.lesson .meta-line { color: var(--text-dim); font-size: .92rem; margin-bottom: 2rem; padding-bottom: 1rem; border-bottom: 1px solid var(--line); }
.lesson .keytake { background: var(--bg-soft); border-left: 3px solid var(--accent); padding: 1rem 1.2rem; border-radius: 0 var(--radius) var(--radius) 0; margin: 1.4rem 0; }
.lesson .keytake h4 { margin: 0 0 .5rem; color: var(--accent); font-size: .82rem; letter-spacing: .12em; text-transform: uppercase; }
.lesson .next { margin-top: 3rem; padding-top: 1.6rem; border-top: 1px solid var(--line); display: flex; justify-content: space-between; gap: 1rem; }
.lesson .next a { display: block; padding: 1rem 1.2rem; border: 1px solid var(--line); border-radius: var(--radius); flex: 1; }
.lesson .next a:hover { border-color: var(--accent); text-decoration: none; }
.lesson .next .label { color: var(--text-dim); font-size: .8rem; letter-spacing: .08em; text-transform: uppercase; }
.lesson .next .name { color: var(--text); font-weight: 600; margin-top: .2rem; }
.lesson .next .prev .label::before { content: "← "; }
.lesson .next .nxt { text-align: right; }
.lesson .next .nxt .label::after { content: " →"; }

/* TOC sidebar on wide screens */
@media (min-width: 1100px) {
    .with-toc { display: grid; grid-template-columns: 1fr 220px; gap: 3rem; max-width: 1000px; margin: 0 auto; }
    .toc { position: sticky; top: 80px; align-self: start; font-size: .9rem; }
    .toc h4 { margin: 0 0 .5rem; color: var(--text-dim); font-size: .75rem; text-transform: uppercase; letter-spacing: .1em; }
    .toc a { display: block; color: var(--text-dim); padding: .25rem 0; border-left: 2px solid transparent; padding-left: .7rem; margin-left: -.7rem; }
    .toc a:hover, .toc a.active { color: var(--text); border-left-color: var(--accent); text-decoration: none; }
}

/* footer */
.site-footer { border-top: 1px solid var(--line); padding: 2.5rem 0; margin-top: 4rem; color: var(--text-dim); font-size: .9rem; }
.site-footer .wrap { display: flex; flex-wrap: wrap; gap: 1.5rem; justify-content: space-between; }
.site-footer a { color: var(--text-dim); }
.site-footer a:hover { color: var(--text); }

/* utility */
.center { text-align: center; }
.muted { color: var(--text-dim); }
.tag { display: inline-block; background: var(--accent-soft); color: var(--accent); border-radius: 99px; padding: .15rem .55rem; font-size: .75rem; font-weight: 600; letter-spacing: .04em; text-transform: uppercase; }
.callout { background: var(--bg-soft); border: 1px solid var(--line); border-radius: var(--radius); padding: 1rem 1.2rem; margin: 1.4rem 0; }
.callout.warn { border-left: 3px solid var(--warn); }
.callout.bad { border-left: 3px solid var(--bad); }
.callout.good { border-left: 3px solid var(--good); }
.copy-row { display: flex; gap: .5rem; align-items: center; background: var(--code-bg); border: 1px solid var(--line); border-radius: var(--radius); padding: .65rem .8rem; font-family: var(--font-mono); font-size: .9rem; overflow-x: auto; }
.copy-row button { margin-left: auto; background: var(--accent); color: #fff; border: 0; border-radius: 6px; padding: .35rem .7rem; cursor: pointer; font-size: .8rem; }

/* numbered step (thank-you page) */
.ty-step-head { display: flex; align-items: center; gap: .9rem; margin-bottom: .3rem; }
.ty-step-head h2 { margin: 0; }
.ty-num {
    display: inline-grid;
    place-items: center;
    width: 38px; height: 38px;
    background: var(--accent);
    color: #fff;
    border-radius: 50%;
    font-weight: 700;
    font-size: 1.1rem;
    flex-shrink: 0;
}
.download-card { display: block; color: var(--text); }
.download-card:hover { text-decoration: none; border-color: var(--accent); }

/* hero — two-column layout: copy on left, form card on right */
.hero { padding: 4rem 0 5rem; text-align: left; }
.hero .badge { margin-bottom: 1rem; }
.hero-grid {
    display: grid;
    grid-template-columns: 1.1fr .9fr;
    gap: 3rem;
    align-items: center;
}
.hero-copy h1 {
    text-align: left;
    margin: 0 0 1rem;
    max-width: 16ch;
}
.hero-copy .lede {
    text-align: left;
    margin: 0 0 1.4rem;
    max-width: none;
    font-size: 1.1rem;
}
.hero-bullets {
    list-style: none;
    padding: 0;
    margin: 0;
    display: grid;
    gap: .6rem;
}
.hero-bullets li {
    position: relative;
    padding-left: 1.6rem;
    color: var(--text-dim);
}
.hero-bullets li::before {
    content: "✓";
    position: absolute;
    left: 0; top: 0;
    color: var(--accent);
    font-weight: 700;
}
.hero-bullets strong { color: var(--text); }

/* opt-in form card (lives in hero on desktop, full-width on mobile) */
.hero-form {
    background: var(--bg-card);
    border: 1px solid var(--line);
    border-radius: 14px;
    padding: 1.6rem 1.6rem 1.4rem;
    box-shadow: 0 10px 40px -20px rgba(0,0,0,.4);
}
.optin-title {
    margin: 0 0 1rem;
    font-size: 1.2rem;
    letter-spacing: -.01em;
}
.optin {
    display: grid;
    gap: .8rem;
}
.optin input[type="email"] {
    width: 100%;
    padding: .95rem 1rem;
    background: var(--bg);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    color: var(--text);
    font-size: 1rem;
    font-family: var(--font-sans);
    outline: none;
    transition: border-color .15s, box-shadow .15s;
}
.optin input[type="email"]:focus {
    border-color: var(--accent);
    box-shadow: 0 0 0 3px color-mix(in srgb, var(--accent) 25%, transparent);
}
.optin input[type="email"]:user-invalid:not(:placeholder-shown) {
    border-color: var(--bad);
}
.btn-block { width: 100%; justify-content: center; padding: .95rem 1.2rem; font-size: 1rem; }
.btn[aria-busy="true"] { pointer-events: none; opacity: .7; }
.btn[aria-busy="true"] .btn-label { visibility: hidden; }
.btn-spinner { display: none; width: 18px; height: 18px; border: 2px solid currentColor; border-top-color: transparent; border-radius: 50%; animation: spin .7s linear infinite; }
.btn[aria-busy="true"] .btn-spinner { display: inline-block; position: absolute; }
@keyframes spin { to { transform: rotate(360deg); } }
.btn { position: relative; }

.optin-fine {
    color: var(--text-dim);
    font-size: .82rem;
    margin: .1rem 0 0;
    line-height: 1.5;
}
.optin .form-err {
    background: color-mix(in srgb, var(--bad) 15%, var(--bg-card));
    border: 1px solid color-mix(in srgb, var(--bad) 50%, var(--line));
    color: var(--text);
    border-radius: var(--radius);
    padding: .6rem .9rem;
    margin: 0;
    font-size: .92rem;
}
.trust-strip {
    list-style: none;
    padding: 0;
    margin: .9rem 0 0;
    display: flex;
    flex-wrap: wrap;
    gap: .35rem .9rem;
    color: var(--text-dim);
    font-size: .82rem;
    border-top: 1px solid var(--line);
    padding-top: .9rem;
}
.visually-hidden {
    position: absolute !important;
    width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden;
    clip: rect(0,0,0,0); white-space: nowrap; border: 0;
}

/* inline mid-page form (single-row on desktop) */
.optin-inline {
    grid-template-columns: 1fr auto;
    gap: .6rem;
    max-width: 540px;
    margin: 0 auto;
}
.optin-inline .btn { white-space: nowrap; }
.optin-inline .optin-fine,
.optin-inline .form-err { grid-column: 1 / -1; }

/* sticky mobile CTA bar */
.mobile-cta {
    display: none;
    position: fixed;
    left: 0; right: 0; bottom: 0;
    padding: .7rem 1rem calc(.7rem + env(safe-area-inset-bottom));
    background: color-mix(in srgb, var(--bg) 95%, transparent);
    border-top: 1px solid var(--line);
    backdrop-filter: blur(10px);
    z-index: 60;
}
.mobile-cta .btn { width: 100%; justify-content: center; }

@media (max-width: 860px) {
    .hero-grid { grid-template-columns: 1fr; gap: 2rem; }
    .hero-copy h1 { max-width: none; }
    .hero { padding: 2.5rem 0 1.5rem; }
}
@media (max-width: 640px) {
    .mobile-cta { display: block; }
    body { padding-bottom: 80px; }
    .optin-inline { grid-template-columns: 1fr; }
    .optin-inline .btn { width: 100%; }
    .trust-strip { font-size: .76rem; gap: .3rem .7rem; }
}

@media (max-width: 640px) {
    .hero { padding: 3rem 0 2rem; }
    .nav a:not(.btn) { display: none; }
    .lesson .next { flex-direction: column; }
    .lesson .next .nxt { text-align: left; }
}