/* ============================================================
   Find My, Powered Off — post styles
   Vanilla CSS. Light/dark via prefers-color-scheme + manual
   data-theme override. Tokens first, then layout, then the
   interactive panels.
   ============================================================ */

/* ---------- Tokens ---------- */

:root {
    --accent: #667eea;
    --accent-2: #764ba2;
    --accent-ink: #4f5fd6;
    --bg: #f7f8fc;
    --bg-card: #ffffff;
    --bg-inset: #eef0f8;
    --text: #1f2430;
    --text-soft: #5a6172;
    --text-faint: #70788c;
    --line: #dfe3ef;
    --line-strong: #c9cede;
    --good: #157e4f;
    --warn: #9a6a12;
    --bad: #c23a47;
    --code-bg: #eceef7;
    --shadow: 0 10px 30px rgba(31, 36, 48, 0.08);
    --ring-color: rgba(102, 126, 234, 0.85);
    --hero-sky-a: #141a38;
    --hero-sky-b: #2b2350;
    --radius: 16px;
    --radius-sm: 10px;
    --mono: ui-monospace, "SF Mono", SFMono-Regular, Menlo, Consolas, monospace;
    color-scheme: light;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) {
        --accent-ink: #9aa8ff;
        --bg: #12141c;
        --bg-card: #1a1d29;
        --bg-inset: #20243363;
        --text: #e8eaf2;
        --text-soft: #aab0c2;
        --text-faint: #8a92a8;
        --line: #2b3042;
        --line-strong: #3a4057;
        --good: #46c98a;
        --warn: #e0a93e;
        --bad: #e87c87;
        --code-bg: #232738;
        --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
        color-scheme: dark;
    }
}

:root[data-theme="dark"] {
    --accent-ink: #9aa8ff;
    --bg: #12141c;
    --bg-card: #1a1d29;
    --bg-inset: #20243363;
    --text: #e8eaf2;
    --text-soft: #aab0c2;
    --text-faint: #8a92a8;
    --line: #2b3042;
    --line-strong: #3a4057;
    --good: #46c98a;
    --warn: #e0a93e;
    --bad: #e87c87;
    --code-bg: #232738;
    --shadow: 0 10px 30px rgba(0, 0, 0, 0.35);
    color-scheme: dark;
}

/* ---------- Base ---------- */

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

html {
    scroll-behavior: smooth;
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    font-size: 1.125rem;
    line-height: 1.72;
    -webkit-font-smoothing: antialiased;
    text-rendering: optimizeLegibility;
}

::selection {
    background: rgba(102, 126, 234, 0.28);
}

a {
    color: var(--accent-ink);
    text-decoration-thickness: 1px;
    text-underline-offset: 2px;
}

a:hover {
    text-decoration-thickness: 2px;
}

:focus-visible {
    outline: 3px solid var(--accent);
    outline-offset: 2px;
    border-radius: 4px;
}

code {
    font-family: var(--mono);
    font-size: 0.85em;
    background: var(--code-bg);
    border-radius: 6px;
    padding: 0.12em 0.4em;
}

strong {
    font-weight: 650;
}

/* ---------- Skip link ---------- */

.skip-link {
    position: absolute;
    left: -9999px;
    top: 12px;
    z-index: 100;
    background: var(--bg-card);
    color: var(--text);
    font-weight: 700;
    padding: 10px 16px;
    border-radius: 10px;
    border: 2px solid var(--accent);
    text-decoration: none;
}

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

/* ---------- Reading progress ---------- */

.progress {
    position: fixed;
    top: 0;
    left: 0;
    height: 3px;
    width: 100%;
    z-index: 60;
    background: transparent;
    pointer-events: none;
}

.progress span {
    display: block;
    height: 100%;
    width: 0;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
}

/* ---------- Top nav ---------- */

.site-nav {
    position: relative;
    z-index: 5;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
    padding: 14px clamp(16px, 4vw, 40px);
}

.site-nav .crumbs {
    display: flex;
    align-items: center;
    gap: 8px;
    font-size: 0.95rem;
    font-weight: 600;
}

.site-nav .crumbs a {
    color: rgba(255, 255, 255, 0.85);
    text-decoration: none;
}

.site-nav .crumbs a:hover {
    color: #ffffff;
    text-decoration: underline;
}

.site-nav .crumbs .sep {
    color: rgba(255, 255, 255, 0.4);
}

.theme-toggle {
    appearance: none;
    border: 1px solid rgba(255, 255, 255, 0.35);
    background: rgba(255, 255, 255, 0.08);
    color: rgba(255, 255, 255, 0.9);
    border-radius: 999px;
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    cursor: pointer;
}

.theme-toggle:hover {
    background: rgba(255, 255, 255, 0.18);
}

.theme-toggle svg {
    width: 18px;
    height: 18px;
    fill: currentColor;
}

.theme-toggle .icon-sun {
    display: none;
}

[data-theme="dark"] .theme-toggle .icon-sun {
    display: block;
}

[data-theme="dark"] .theme-toggle .icon-moon {
    display: none;
}

@media (prefers-color-scheme: dark) {
    :root:not([data-theme="light"]) .theme-toggle .icon-sun {
        display: block;
    }

    :root:not([data-theme="light"]) .theme-toggle .icon-moon {
        display: none;
    }
}

/* ---------- Hero ---------- */

.hero {
    position: relative;
    background:
        radial-gradient(1200px 500px at 70% -10%, rgba(118, 75, 162, 0.55), transparent 60%),
        linear-gradient(180deg, var(--hero-sky-b) 0%, var(--hero-sky-a) 78%);
    color: #f2f3fb;
    overflow: hidden;
    margin-top: -69px;
    padding-top: 69px;
}

.hero-inner {
    max-width: 70rem;
    margin: 0 auto;
    padding: clamp(20px, 4vw, 48px) clamp(16px, 4vw, 40px) 0;
}

.hero h1 {
    font-size: clamp(1.9rem, 4.6vw, 3.1rem);
    line-height: 1.12;
    letter-spacing: -0.02em;
    max-width: 24ch;
    font-weight: 750;
}

.hero .dek {
    margin-top: 16px;
    max-width: 58ch;
    font-size: clamp(1.05rem, 1.8vw, 1.25rem);
    line-height: 1.6;
    color: rgba(238, 240, 252, 0.82);
}

.hero .meta {
    margin-top: 18px;
    display: flex;
    flex-wrap: wrap;
    gap: 8px 18px;
    font-size: 0.9rem;
    color: rgba(238, 240, 252, 0.6);
}

.hero-scene {
    display: block;
    width: 100%;
    max-width: 70rem;
    margin: 8px auto 0;
}

/* Hero scene animation (one shared 12s timeline) */

.hs-ring {
    transform-box: fill-box;
    transform-origin: center;
    opacity: 0;
    animation: hs-ring 3.6s linear infinite;
}

.hs-ring.r2 {
    animation-delay: 1.2s;
}

.hs-ring.r3 {
    animation-delay: 2.4s;
}

@keyframes hs-ring {
    0% {
        transform: scale(0.18);
        opacity: 0.75;
    }

    80% {
        opacity: 0.12;
    }

    100% {
        transform: scale(2.4);
        opacity: 0;
    }
}

.hs-walker {
    animation: hs-walk 12s linear infinite;
}

@keyframes hs-walk {
    0% {
        transform: translateX(0);
    }

    100% {
        transform: translateX(-1090px);
    }
}

.hs-halo {
    opacity: 0;
    animation: hs-halo 12s linear infinite;
}

@keyframes hs-halo {

    0%,
    74% {
        opacity: 0;
    }

    78% {
        opacity: 0.9;
    }

    84%,
    100% {
        opacity: 0;
    }
}

.hs-envelope {
    opacity: 0;
    animation: hs-envelope 12s linear infinite;
}

@keyframes hs-envelope {

    0%,
    78% {
        opacity: 0;
        transform: translate(0, 0) scale(0.7);
    }

    80% {
        opacity: 1;
        transform: translate(30px, -30px) scale(1);
    }

    90% {
        opacity: 1;
        transform: translate(360px, -118px) scale(1);
    }

    93%,
    100% {
        opacity: 0;
        transform: translate(385px, -124px) scale(0.7);
    }
}

.hs-cloudglow {
    opacity: 0;
    animation: hs-cloudglow 12s linear infinite;
}

@keyframes hs-cloudglow {

    0%,
    89% {
        opacity: 0;
    }

    92% {
        opacity: 0.85;
    }

    97%,
    100% {
        opacity: 0;
    }
}

.hs-pin {
    transform-box: fill-box;
    transform-origin: 50% 100%;
    transform: scale(0);
    animation: hs-pin 12s ease-out infinite;
}

@keyframes hs-pin {

    0%,
    93% {
        transform: scale(0);
        opacity: 0;
    }

    96% {
        transform: scale(1.12);
        opacity: 1;
    }

    98% {
        transform: scale(1);
        opacity: 1;
    }

    100% {
        transform: scale(1);
        opacity: 0;
    }
}

.hs-star {
    animation: hs-twinkle 4.8s ease-in-out infinite;
}

.hs-star.s2 {
    animation-delay: 1.6s;
}

.hs-star.s3 {
    animation-delay: 3.2s;
}

@keyframes hs-twinkle {

    0%,
    100% {
        opacity: 0.35;
    }

    50% {
        opacity: 0.9;
    }
}

.hs-static {
    display: none;
}

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

    .hs-ring,
    .hs-walker,
    .hs-halo,
    .hs-envelope,
    .hs-cloudglow,
    .hs-pin,
    .hs-star {
        animation: none !important;
    }

    .hs-walker,
    .hs-envelope,
    .hs-halo {
        opacity: 0;
    }

    .hs-pin {
        transform: scale(1);
        opacity: 1;
    }

    .hs-ring {
        opacity: 0.4;
        transform: scale(1);
    }

    .hs-static {
        display: block;
    }
}

/* ---------- Layout: centered column with wide breakouts ---------- */

.layout {
    display: grid;
    grid-template-columns: 1fr min(43rem, 100% - 2.5rem) 1fr;
    row-gap: 0;
    padding-bottom: 80px;
}

.layout > * {
    grid-column: 2;
    min-width: 0;
}

.layout > .breakout {
    grid-column: 1 / -1;
    justify-self: center;
    width: min(68rem, 100% - 2rem);
    min-width: 0;
}

.layout > p,
.layout > ul,
.layout > ol,
.layout > blockquote {
    margin: 0 0 1.35em;
}

.layout > ul,
.layout > ol {
    padding-left: 1.4em;
}

.layout li {
    margin-bottom: 0.5em;
}

.layout li::marker {
    color: var(--accent-ink);
}

.kicker {
    margin: 64px 0 6px;
    font-size: 0.85rem;
    font-weight: 700;
    letter-spacing: 0.14em;
    text-transform: uppercase;
    color: var(--accent-ink);
}

.layout h2 {
    font-size: clamp(1.55rem, 3vw, 2rem);
    line-height: 1.2;
    letter-spacing: -0.015em;
    margin: 0 0 18px;
    font-weight: 720;
    scroll-margin-top: 80px;
}

.layout h3 {
    font-size: 1.22rem;
    margin: 40px 0 12px;
    font-weight: 680;
    scroll-margin-top: 80px;
}

.lede {
    font-size: 1.28rem;
    line-height: 1.62;
    color: var(--text);
}

.divider {
    display: flex;
    justify-content: center;
    gap: 14px;
    margin: 56px 0 0;
    color: var(--text-faint);
    font-size: 0.8rem;
    letter-spacing: 0.4em;
    user-select: none;
}

/* ---------- Callouts ---------- */

.callout {
    border: 1px solid var(--line);
    border-left: 4px solid var(--accent);
    background: var(--bg-card);
    border-radius: var(--radius-sm);
    padding: 16px 18px;
    margin: 0 0 1.35em;
    font-size: 1.02rem;
}

.callout.warn {
    border-left-color: var(--warn);
}

.callout.tip {
    border-left-color: var(--good);
}

.callout .co-title {
    display: block;
    font-weight: 700;
    font-size: 0.92rem;
    margin-bottom: 4px;
}

/* ---------- Figures ---------- */

figure.fig {
    margin: 28px 0 36px;
}

figure.fig svg {
    display: block;
    width: 100%;
    height: auto;
}

figure.fig figcaption {
    margin-top: 10px;
    font-size: 0.92rem;
    color: var(--text-soft);
    text-align: center;
}

.fig-frame {
    background: var(--bg-card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    padding: clamp(10px, 2.5vw, 26px);
    box-shadow: var(--shadow);
}

/* Shared diagram text styles (SVG) */

.dia-label {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 13px;
    fill: var(--text-soft);
}

.dia-label.strong {
    fill: var(--text);
    font-weight: 650;
}

.dia-mono {
    font-family: var(--mono);
    font-size: 11.5px;
    fill: var(--text-soft);
}

.dia-stroke {
    stroke: var(--line-strong);
    fill: none;
}

.dia-arrow {
    stroke: var(--text-faint);
    fill: none;
    stroke-width: 1.6;
    stroke-dasharray: 5 5;
}

.dia-arrowhead {
    fill: var(--text-faint);
}

/* ---------- Interactive panels ---------- */

.panel {
    background: var(--bg-card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    margin: 30px 0 44px;
    overflow: hidden;
}

.panel-head {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    justify-content: space-between;
    gap: 10px;
    padding: 14px 20px;
    border-bottom: 1px solid var(--line);
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.10), rgba(118, 75, 162, 0.10));
}

.panel-head h3 {
    margin: 0;
    font-size: 1.02rem;
    font-weight: 700;
}

.panel-head .panel-tag {
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    color: var(--accent-ink);
    border: 1px solid var(--accent-ink);
    border-radius: 999px;
    padding: 3px 10px;
    white-space: nowrap;
}

.panel-body {
    padding: 20px;
}

.panel-foot {
    padding: 12px 20px;
    border-top: 1px dashed var(--line);
    font-size: 0.88rem;
    color: var(--text-soft);
}

.panel-foot p {
    margin: 0;
}

/* Controls */

.controls {
    display: flex;
    flex-wrap: wrap;
    align-items: center;
    gap: 14px 22px;
    margin-bottom: 16px;
}

.control {
    display: flex;
    align-items: center;
    gap: 10px;
    font-size: 0.92rem;
    color: var(--text-soft);
}

.control label {
    font-weight: 600;
    color: var(--text);
    white-space: nowrap;
}

.control output {
    font-variant-numeric: tabular-nums;
    min-width: 2.2em;
    text-align: right;
    color: var(--text-soft);
}

input[type="range"] {
    accent-color: var(--accent);
    width: 130px;
}

.btn {
    appearance: none;
    border: 1px solid var(--line-strong);
    background: var(--bg-card);
    color: var(--text);
    font: inherit;
    font-size: 0.92rem;
    font-weight: 600;
    border-radius: 10px;
    padding: 8px 16px;
    cursor: pointer;
    transition: transform 0.12s ease, box-shadow 0.12s ease;
}

.btn:hover {
    transform: translateY(-1px);
    box-shadow: 0 4px 12px rgba(31, 36, 48, 0.12);
}

.btn:active {
    transform: translateY(0);
}

.btn-primary {
    background: linear-gradient(135deg, var(--accent), var(--accent-2));
    border-color: transparent;
    color: #ffffff;
}

.btn[disabled] {
    opacity: 0.45;
    cursor: not-allowed;
    transform: none;
    box-shadow: none;
}

.seg {
    display: inline-flex;
    border: 1px solid var(--line-strong);
    border-radius: 10px;
    overflow: hidden;
}

.seg button {
    appearance: none;
    border: none;
    background: transparent;
    color: var(--text-soft);
    font: inherit;
    font-size: 0.88rem;
    font-weight: 600;
    padding: 7px 13px;
    cursor: pointer;
}

.seg button + button {
    border-left: 1px solid var(--line);
}

.seg button[aria-pressed="true"] {
    background: var(--accent);
    color: #ffffff;
}

/* Switch */

.switch {
    display: inline-flex;
    align-items: center;
    gap: 10px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.92rem;
}

.switch input {
    position: absolute;
    opacity: 0;
    pointer-events: none;
}

.switch .track {
    width: 42px;
    height: 24px;
    border-radius: 999px;
    background: var(--line-strong);
    position: relative;
    transition: background 0.15s ease;
    flex: none;
}

.switch .track::after {
    content: "";
    position: absolute;
    top: 3px;
    left: 3px;
    width: 18px;
    height: 18px;
    border-radius: 50%;
    background: #ffffff;
    box-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
    transition: transform 0.15s ease;
}

.switch input:checked + .track {
    background: var(--accent);
}

.switch input:checked + .track::after {
    transform: translateX(18px);
}

.switch input:focus-visible + .track {
    outline: 3px solid var(--accent);
    outline-offset: 2px;
}

/* Stats chips */

.stat-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(140px, 1fr));
    gap: 10px;
    margin-top: 16px;
}

.stat {
    background: var(--bg-inset);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 10px 14px;
}

.stat .label {
    display: block;
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    color: var(--text-faint);
}

.stat .value {
    display: block;
    font-size: 1.25rem;
    font-weight: 700;
    font-variant-numeric: tabular-nums;
}

.stat .value small {
    font-size: 0.8rem;
    font-weight: 600;
    color: var(--text-soft);
}

/* Sim canvas */

.sim-canvas {
    display: block;
    width: 100%;
    border-radius: var(--radius-sm);
    border: 1px solid var(--line);
    background: var(--bg-inset);
    touch-action: manipulation;
}

/* ---------- Power scale explorer ---------- */

.power-pickers {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
    margin-bottom: 18px;
}

@media (max-width: 720px) {
    .power-pickers {
        grid-template-columns: 1fr;
    }
}

.picker h4 {
    font-size: 0.82rem;
    font-weight: 700;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: var(--text-faint);
    margin-bottom: 8px;
}

.chip-row {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

.chip {
    appearance: none;
    border: 1.5px solid var(--line-strong);
    background: var(--bg-card);
    color: var(--text);
    font: inherit;
    font-size: 0.88rem;
    font-weight: 600;
    border-radius: 999px;
    padding: 7px 14px;
    cursor: pointer;
}

.chip[aria-pressed="true"] {
    border-color: var(--accent);
    background: rgba(102, 126, 234, 0.14);
    color: var(--accent-ink);
}

.power-result {
    background: var(--bg-inset);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 18px 20px;
    text-align: center;
}

.power-result .headline {
    font-size: clamp(1.4rem, 3.4vw, 2rem);
    font-weight: 760;
    letter-spacing: -0.01em;
}

.power-result .sub {
    margin-top: 6px;
    color: var(--text-soft);
    font-size: 0.95rem;
}

.power-bar {
    position: relative;
    height: 14px;
    border-radius: 999px;
    background: var(--line);
    margin: 16px 0 6px;
    overflow: hidden;
}

.power-bar span {
    position: absolute;
    inset: 0 auto 0 0;
    width: 0;
    border-radius: 999px;
    background: linear-gradient(90deg, var(--accent), var(--accent-2));
    transition: width 0.5s ease;
}

.power-scale-note {
    display: flex;
    justify-content: space-between;
    font-size: 0.78rem;
    color: var(--text-faint);
    font-variant-numeric: tabular-nums;
}

/* ---------- Key rotation demo ---------- */

.rot-grid {
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 18px;
}

@media (max-width: 760px) {
    .rot-grid {
        grid-template-columns: 1fr;
    }
}

.rot-col h4 {
    font-size: 0.95rem;
    margin-bottom: 10px;
    display: flex;
    align-items: center;
    gap: 8px;
}

.rot-col h4 .badge {
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    border-radius: 999px;
    padding: 2px 9px;
}

.badge.stranger {
    background: rgba(211, 84, 96, 0.14);
    color: var(--bad);
}

.badge.owner {
    background: rgba(30, 158, 99, 0.14);
    color: var(--good);
}

.id-log {
    list-style: none;
    padding: 0;
    margin: 0;
    font-family: var(--mono);
    font-size: 0.84rem;
    display: flex;
    flex-direction: column;
    gap: 6px;
    min-height: 220px;
}

.id-log li {
    display: flex;
    align-items: center;
    gap: 10px;
    background: var(--bg-inset);
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 7px 10px;
    margin: 0;
}

.id-log .dot {
    width: 12px;
    height: 12px;
    border-radius: 50%;
    flex: none;
}

.id-log .t {
    color: var(--text-faint);
    font-size: 0.76rem;
    min-width: 4.4em;
}

.id-log .verdict {
    margin-left: auto;
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 0.78rem;
    font-weight: 700;
}

.id-log .verdict.mine {
    color: var(--good);
}

.id-log .verdict.unknown {
    color: var(--text-faint);
}

.rot-now {
    display: flex;
    align-items: center;
    gap: 12px;
    background: var(--bg-inset);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    margin-bottom: 16px;
    flex-wrap: wrap;
}

.rot-now .clock {
    font-variant-numeric: tabular-nums;
    font-weight: 700;
    font-size: 1.05rem;
}

.rot-now .current-id {
    font-family: var(--mono);
    font-size: 0.9rem;
    display: inline-flex;
    align-items: center;
    gap: 8px;
}

/* ---------- Crypto demo ---------- */

.crypto-steps {
    counter-reset: step;
    display: flex;
    flex-direction: column;
    gap: 14px;
}

.cstep {
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 16px 18px 16px 58px;
    position: relative;
    background: var(--bg-inset);
    transition: border-color 0.2s ease, opacity 0.2s ease;
}

.cstep::before {
    counter-increment: step;
    content: counter(step);
    position: absolute;
    left: 16px;
    top: 16px;
    width: 28px;
    height: 28px;
    border-radius: 50%;
    background: var(--line);
    color: var(--text-soft);
    font-weight: 700;
    font-size: 0.9rem;
    display: flex;
    align-items: center;
    justify-content: center;
}

.cstep.active {
    border-color: var(--accent);
}

.cstep.active::before {
    background: linear-gradient(135deg, var(--accent), var(--accent-2));
    color: #ffffff;
}

.cstep.locked {
    opacity: 0.55;
}

.cstep h4 {
    font-size: 1rem;
    margin-bottom: 6px;
}

.cstep p {
    font-size: 0.95rem;
    color: var(--text-soft);
    margin: 0 0 10px;
}

.cstep .row {
    display: flex;
    flex-wrap: wrap;
    gap: 10px;
    align-items: center;
}

.keycard {
    display: inline-flex;
    align-items: center;
    gap: 8px;
    border: 1.5px solid var(--line-strong);
    border-radius: 10px;
    padding: 8px 12px;
    font-family: var(--mono);
    font-size: 0.8rem;
    background: var(--bg-card);
    max-width: 100%;
    overflow-wrap: anywhere;
}

.keycard.pub {
    border-color: var(--accent);
}

.keycard.priv {
    border-color: var(--warn);
}

.keycard .kc-tag {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, sans-serif;
    font-size: 0.7rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    white-space: nowrap;
}

.keycard.pub .kc-tag {
    color: var(--accent-ink);
}

.keycard.priv .kc-tag {
    color: var(--warn);
}

.hexblob {
    font-family: var(--mono);
    font-size: 0.78rem;
    line-height: 1.55;
    background: var(--code-bg);
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 10px 12px;
    overflow-wrap: anywhere;
    max-height: 96px;
    overflow-y: auto;
    width: 100%;
}

.cstep .result {
    margin-top: 10px;
    font-size: 0.95rem;
    font-weight: 600;
}

.result.ok {
    color: var(--good);
}

.result.fail {
    color: var(--bad);
}

.loc-picker {
    display: flex;
    flex-wrap: wrap;
    gap: 8px;
}

/* ---------- Packet anatomy ---------- */

.byte-views {
    margin-bottom: 14px;
}

.byte-section {
    margin-bottom: 18px;
}

.byte-section h4 {
    font-size: 0.82rem;
    font-weight: 700;
    letter-spacing: 0.07em;
    text-transform: uppercase;
    color: var(--text-faint);
    margin-bottom: 8px;
}

.byte-grid {
    display: flex;
    flex-wrap: wrap;
    gap: 5px;
}

.byte {
    appearance: none;
    font-family: var(--mono);
    font-size: 0.82rem;
    font-weight: 600;
    width: 40px;
    height: 40px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    border-radius: 8px;
    border: 1.5px solid transparent;
    cursor: pointer;
    color: var(--text);
    transition: transform 0.1s ease;
}

.byte:hover {
    transform: translateY(-2px);
}

.byte.sel {
    border-color: var(--text);
    transform: translateY(-2px);
}

.b-addr {
    background: rgba(102, 126, 234, 0.20);
}

.b-frame {
    background: rgba(138, 144, 162, 0.22);
}

.b-status {
    background: rgba(201, 138, 27, 0.22);
}

.b-key {
    background: rgba(30, 158, 99, 0.18);
}

.b-bits {
    background: rgba(211, 84, 96, 0.18);
}

.byte-legend {
    display: flex;
    flex-wrap: wrap;
    gap: 8px 16px;
    font-size: 0.82rem;
    color: var(--text-soft);
    margin: 10px 0 14px;
}

.byte-legend .lg {
    display: inline-flex;
    align-items: center;
    gap: 6px;
}

.byte-legend .sw {
    width: 14px;
    height: 14px;
    border-radius: 4px;
    display: inline-block;
}

.byte-detail {
    min-height: 76px;
    background: var(--bg-inset);
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 12px 16px;
    font-size: 0.95rem;
}

.byte-detail .bd-title {
    font-weight: 700;
    font-family: var(--mono);
    font-size: 0.88rem;
}

.byte-detail p {
    margin: 4px 0 0;
    color: var(--text-soft);
    font-size: 0.92rem;
}

/* ---------- Who knows what cards ---------- */

.who-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 14px;
    margin: 24px 0 40px;
}

.who-card {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--bg-card);
    box-shadow: var(--shadow);
    overflow: hidden;
}

.who-card summary {
    list-style: none;
    cursor: pointer;
    padding: 16px 18px;
    display: flex;
    align-items: center;
    gap: 12px;
    font-weight: 700;
}

.who-card summary::-webkit-details-marker {
    display: none;
}

.who-card summary .who-icon {
    width: 38px;
    height: 38px;
    border-radius: 10px;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    background: linear-gradient(135deg, rgba(102, 126, 234, 0.18), rgba(118, 75, 162, 0.18));
    flex: none;
}

.who-card summary .who-icon svg {
    width: 20px;
    height: 20px;
    stroke: var(--accent-ink);
    fill: none;
    stroke-width: 1.8;
    stroke-linecap: round;
    stroke-linejoin: round;
}

.who-card summary .chev {
    margin-left: auto;
    color: var(--text-faint);
    transition: transform 0.2s ease;
}

.who-card[open] summary .chev {
    transform: rotate(180deg);
}

.who-body {
    padding: 0 18px 16px;
    font-size: 0.95rem;
}

.who-body h5 {
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.08em;
    text-transform: uppercase;
    margin: 10px 0 4px;
}

.who-body h5.knows {
    color: var(--good);
}

.who-body h5.doesnt {
    color: var(--bad);
}

.who-body ul {
    padding-left: 1.2em;
    margin: 0;
}

.who-body li {
    margin-bottom: 0.25em;
    color: var(--text-soft);
}

/* ---------- Timeline ---------- */

.timeline {
    list-style: none;
    padding: 0;
    margin: 28px 0 40px;
    position: relative;
}

.timeline::before {
    content: "";
    position: absolute;
    left: 7px;
    top: 6px;
    bottom: 6px;
    width: 2px;
    background: linear-gradient(180deg, var(--accent), var(--accent-2));
    opacity: 0.5;
}

.tl-item {
    position: relative;
    padding: 0 0 26px 36px;
    margin: 0;
}

.tl-item::before {
    content: "";
    position: absolute;
    left: 0;
    top: 6px;
    width: 16px;
    height: 16px;
    border-radius: 50%;
    background: var(--bg);
    border: 3px solid var(--accent);
}

.tl-item.milestone::before {
    background: var(--accent);
    box-shadow: 0 0 0 5px rgba(102, 126, 234, 0.18);
}

.tl-year {
    font-size: 0.8rem;
    font-weight: 800;
    letter-spacing: 0.08em;
    color: var(--accent-ink);
}

.tl-item h4 {
    font-size: 1.05rem;
    margin: 2px 0 4px;
}

.tl-item p {
    margin: 0;
    font-size: 0.95rem;
    color: var(--text-soft);
}

.tl-item {
    opacity: 0;
    transform: translateY(14px);
    transition: opacity 0.5s ease, transform 0.5s ease;
}

.tl-item.revealed {
    opacity: 1;
    transform: none;
}

@media (prefers-reduced-motion: reduce) {
    .tl-item {
        opacity: 1;
        transform: none;
        transition: none;
    }
}

/* ---------- Comparison table ---------- */

.table-scroll {
    overflow-x: auto;
    margin: 24px 0 8px;
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    background: var(--bg-card);
}

table.compare {
    border-collapse: collapse;
    width: 100%;
    min-width: 720px;
    font-size: 0.92rem;
}

table.compare th,
table.compare td {
    padding: 11px 14px;
    text-align: left;
    border-bottom: 1px solid var(--line);
    vertical-align: top;
}

table.compare thead th {
    background: var(--bg-inset);
    font-size: 0.8rem;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    color: var(--text-soft);
    position: sticky;
    top: 0;
}

table.compare tbody tr:last-child td {
    border-bottom: none;
}

table.compare td:first-child,
table.compare th:first-child {
    font-weight: 650;
    white-space: nowrap;
}

/* ---------- Quiz ---------- */

.quiz fieldset {
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    padding: 16px 18px;
    margin-bottom: 14px;
    background: var(--bg-inset);
}

.quiz legend {
    font-weight: 700;
    font-size: 1rem;
    padding: 0 6px;
}

.quiz .opts {
    display: flex;
    flex-direction: column;
    gap: 8px;
    margin-top: 8px;
}

.quiz label.opt {
    display: flex;
    gap: 10px;
    align-items: flex-start;
    background: var(--bg-card);
    border: 1.5px solid var(--line);
    border-radius: 10px;
    padding: 10px 14px;
    cursor: pointer;
    font-size: 0.97rem;
    transition: border-color 0.15s ease;
}

.quiz label.opt:hover {
    border-color: var(--accent);
}

.quiz label.opt input {
    accent-color: var(--accent);
    margin-top: 4px;
}

.quiz label.opt.correct {
    border-color: var(--good);
    background: rgba(30, 158, 99, 0.08);
}

.quiz label.opt.incorrect {
    border-color: var(--bad);
    background: rgba(211, 84, 96, 0.08);
}

.q-explain {
    margin-top: 10px;
    font-size: 0.92rem;
    color: var(--text-soft);
    border-left: 3px solid var(--accent);
    padding-left: 12px;
    display: none;
}

.q-explain.show {
    display: block;
}

.quiz-score {
    text-align: center;
    font-size: 1.15rem;
    font-weight: 700;
    padding: 14px;
    border-radius: var(--radius-sm);
    background: var(--bg-inset);
    border: 1px solid var(--line);
}

/* ---------- FAQ ---------- */

.faq {
    margin: 24px 0 40px;
    display: flex;
    flex-direction: column;
    gap: 10px;
}

.faq details {
    border: 1px solid var(--line);
    border-radius: var(--radius-sm);
    background: var(--bg-card);
    padding: 0;
}

.faq summary {
    cursor: pointer;
    font-weight: 650;
    padding: 14px 18px;
    list-style: none;
    display: flex;
    align-items: center;
    gap: 10px;
}

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

.faq summary::before {
    content: "+";
    font-weight: 700;
    color: var(--accent-ink);
    width: 1em;
    flex: none;
}

.faq details[open] summary::before {
    content: "–";
}

.faq .faq-a {
    padding: 0 18px 16px 44px;
    color: var(--text-soft);
    font-size: 0.98rem;
}

.faq .faq-a p {
    margin: 0 0 0.8em;
}

.faq .faq-a p:last-child {
    margin-bottom: 0;
}

/* ---------- Sources & footer ---------- */

.sources {
    font-size: 0.92rem;
    color: var(--text-soft);
    padding-left: 1.6em;
}

.sources li {
    margin-bottom: 0.6em;
}

.colophon {
    margin-top: 56px;
    border-top: 1px solid var(--line);
    padding-top: 22px;
    font-size: 0.9rem;
    color: var(--text-faint);
}

.colophon a {
    color: var(--text-soft);
}

.post-footer-nav {
    display: flex;
    justify-content: space-between;
    gap: 12px;
    margin-top: 26px;
    font-weight: 600;
    font-size: 0.95rem;
}

/* ---------- Back to top ---------- */

.back-top {
    position: fixed;
    right: 18px;
    bottom: 18px;
    z-index: 50;
    width: 44px;
    height: 44px;
    border-radius: 50%;
    border: 1px solid var(--line-strong);
    background: var(--bg-card);
    color: var(--text);
    box-shadow: var(--shadow);
    cursor: pointer;
    display: flex;
    align-items: center;
    justify-content: center;
    opacity: 0;
    pointer-events: none;
    transition: opacity 0.25s ease;
}

.back-top.show {
    opacity: 1;
    pointer-events: auto;
}

/* ---------- TOC ---------- */

.toc {
    border: 1px solid var(--line);
    border-radius: var(--radius);
    background: var(--bg-card);
    padding: 6px 18px 14px;
    margin: 34px 0 10px;
    font-size: 0.95rem;
}

.toc summary {
    cursor: pointer;
    font-weight: 700;
    padding: 10px 0 6px;
    list-style: none;
}

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

.toc ol {
    margin: 6px 0 0;
    padding-left: 1.5em;
    columns: 2;
    column-gap: 32px;
}

@media (max-width: 640px) {
    .toc ol {
        columns: 1;
    }
}

.toc li {
    margin-bottom: 0.45em;
    break-inside: avoid;
}

.toc a {
    text-decoration: none;
    color: var(--text-soft);
}

.toc a:hover {
    color: var(--accent-ink);
    text-decoration: underline;
}

/* ---------- No-JS notice ---------- */

.needs-js {
    display: none;
    margin: 0;
    padding: 12px 16px;
    font-size: 0.92rem;
}

.no-js .needs-js {
    display: block;
}

/* ---------- Print ---------- */

@media print {

    .site-nav,
    .progress,
    .back-top,
    .theme-toggle,
    .panel,
    .quiz {
        display: none !important;
    }

    body {
        background: #ffffff;
        color: #000000;
    }
}