/* === Registered Custom Properties (enables smooth color transitions) === */
@property --bg {
    syntax: "<color>";
    inherits: true;
    initial-value: #06070d;
}
@property --text {
    syntax: "<color>";
    inherits: true;
    initial-value: #e4e7ee;
}
@property --mid {
    syntax: "<color>";
    inherits: true;
    initial-value: #7a8499;
}
@property --line {
    syntax: "<color>";
    inherits: true;
    initial-value: #1e2330;
}
@property --accent {
    syntax: "<color>";
    inherits: true;
    initial-value: #00d9ff;
}
@property --accent-2 {
    syntax: "<color>";
    inherits: true;
    initial-value: #b66dff;
}
@property --surface-1 {
    syntax: "<color>";
    inherits: true;
    initial-value: #0d1018;
}
@property --surface-2 {
    syntax: "<color>";
    inherits: true;
    initial-value: #141823;
}

/* === Scene Palettes ===
   Cyber-tech aesthetic: cyan (#00d9ff) primary + violet (#b66dff) secondary.
   Sunny = high-contrast cool light; Night = deep void with neon accents. */
[data-scene="sunny"] {
    --bg: #fafbfc;
    --bg-translucent: rgba(250, 251, 252, 0.6);
    --surface-1: #f2f4f8;
    --surface-2: #e8ecf2;
    --text: #0a0e14;
    --mid: #6b7280;
    --line: #d8dde6;
    --accent: #0099b8;
    --accent-2: #8b5cf6;
    --neon-glow: rgba(0, 153, 184, 0.25);
    --neon-glow-2: rgba(139, 92, 246, 0.22);
    --grid-line: rgba(10, 14, 20, 0.035);
    --grid-size: var(--grid-cell, 28px);
    --grad-text: linear-gradient(110deg, #0099b8 0%, #8b5cf6 100%);
    background-color: var(--bg);
    background-image:
        linear-gradient(var(--grid-line) 1px, transparent 1px),
        linear-gradient(90deg, var(--grid-line) 1px, transparent 1px),
        var(--sunny-bg-image, none);
    background-size: var(--grid-size) var(--grid-size), var(--grid-size) var(--grid-size), cover;
    background-position: center;
    background-attachment: fixed;
}

[data-scene="sunny"] body {
    background-color: var(--bg-translucent, var(--bg));
}

[data-scene="night"] {
    --bg: #06070d;
    --bg-solid: #06070d;
    --bg-translucent: rgba(6, 7, 13, 0.6);
    --surface-1: #0d1018;
    --surface-2: #141823;
    --text: #e4e7ee;
    --mid: #7a8499;
    --line: #1e2330;
    --accent: #00d9ff;
    --accent-2: #b66dff;
    --neon-glow: rgba(0, 217, 255, 0.4);
    --neon-glow-2: rgba(182, 109, 255, 0.4);
    --grid-line: rgba(255, 255, 255, 0.028);
    --grid-size: var(--grid-cell, 28px);
    --grad-text: linear-gradient(110deg, #00d9ff 0%, #b66dff 100%);
    background-color: var(--bg);
    background-image:
        linear-gradient(var(--grid-line) 1px, transparent 1px),
        linear-gradient(90deg, var(--grid-line) 1px, transparent 1px),
        var(--night-bg-image, none);
    background-size: var(--grid-size) var(--grid-size), var(--grid-size) var(--grid-size), cover;
    background-position: center;
    background-attachment: fixed;
}

[data-scene="night"] body {
    background-color: var(--bg-translucent, var(--bg));
}

/* === Transition === */
html {
    transition:
        --bg 0.3s ease,
        --text 0.3s ease,
        --mid 0.3s ease,
        --line 0.3s ease,
        --accent 0.3s ease,
        --accent-2 0.3s ease,
        --surface-1 0.3s ease,
        --surface-2 0.3s ease;
}

/* === Reset === */
*,
*::before,
*::after {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

/* === Font Stack ===
   --font-display  bold titles / hero / year badges
   --font-body     normal reading content (sans, restrained)
   --font-mono     code, numbers, kbd, dates */
:root {
    --font-display: "Space Grotesk", "HarmonyOS Sans SC", "PingFang SC", -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
    --font-body:    "Inter", "HarmonyOS Sans SC", "PingFang SC", -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans SC", "Helvetica Neue", Helvetica, Arial, sans-serif;
    --font-mono:    "JetBrains Mono", "SF Mono", "Cascadia Code", "Fira Code", "Menlo", "Consolas", monospace;
    --container-width: 950px;
}

/* === Base === */
html {
    scroll-behavior: smooth;
    font-size: var(--base-font-size, 16px);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    overflow-y: scroll;
    scrollbar-gutter: stable;
}

body {
    font-family: var(--font-family, var(--font-body));
    background-color: var(--bg);
    color: var(--text);
    line-height: 1.75;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    transition:
        background-color 0.3s ease,
        color 0.3s ease;
}

/* === Typography === */
h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-display);
    font-weight: 700;
    line-height: 1.2;
    color: var(--text);
    letter-spacing: -0.02em;
}

h1 {
    font-size: clamp(1.85rem, 3vw, 2.4rem);
    margin-bottom: 0.6em;
    letter-spacing: -0.035em;
}
h2 {
    font-size: 1.5rem;
    margin-bottom: 0.5em;
    letter-spacing: -0.025em;
}
h3 {
    font-size: 1.2rem;
    margin-bottom: 0.4em;
    letter-spacing: -0.02em;
}

p {
    margin-bottom: 1.2em;
    color: var(--text);
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.2s ease, text-shadow 0.2s ease;
}

a:hover {
    color: var(--accent);
    text-shadow: 0 0 12px var(--neon-glow);
}

code {
    font-family: var(--code-font-family, var(--font-mono));
    font-size: 0.85em;
    background: var(--surface-2);
    color: var(--accent);
    padding: 0.15em 0.45em;
    border-radius: 4px;
    border: 1px solid var(--line);
    transition: background-color 0.3s ease, border-color 0.3s ease;
}

pre {
    border-radius: 6px;
    overflow-x: auto;
    margin-bottom: 1.5em;
    line-height: 1.6;
    transition: background-color 0.3s ease;
}

pre code {
    background: none;
    padding: 0;
    font-size: 0.82rem;
    border-radius: 0;
}

/* Hugo Chroma highlight wrapper */
.highlight {
    margin-bottom: 1.5em;
    position: relative;
}

.highlight pre {
    margin: 0;
    padding: 1em 1.2em;
}

.chroma {
    background: var(--surface-2) !important;
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 1em 1.2em;
    overflow-x: auto;
    transition: background-color 0.3s ease, color 0.3s ease, border-color 0.3s ease;
}

/* Standalone pre (no Chroma wrapper) */
pre:not(.chroma) {
    background: var(--surface-2);
    border: 1px solid var(--line);
    border-radius: 8px;
    padding: 1em 1.2em;
}

/* Inline code inside code blocks should not get the inline color treatment */
pre code,
.chroma code {
    color: inherit;
    border: none;
}

blockquote {
    border-left: 3px solid var(--accent);
    background: var(--surface-1);
    padding: 0.8em 1em 0.8em 1.2em;
    margin: 1.2em 0;
    color: var(--mid);
    border-radius: 0 6px 6px 0;
    transition:
        border-color 0.3s ease,
        background-color 0.3s ease,
        color 0.3s ease;
}

hr {
    border: none;
    border-top: 1px solid var(--line);
    margin: 2em 0;
    transition: border-color 0.3s ease;
}

img {
    max-width: 100%;
    height: auto;
    border-radius: 6px;
}

/* === Layout === */
.container {
    max-width: var(--container-width, 850px);
    margin: 0 auto;
    padding: 0 1.5rem;
}

.site-main {
    position: relative;
    z-index: 10;
    padding: 2rem 0 4rem;
    flex: 1;
}

.site-main > .container {
    max-width: var(--container-width, 850px);
}

/* === Scene Layer (atmospheric effects overlay) === */
.scene-layer {
    position: fixed;
    inset: 0;
    z-index: 1;
    pointer-events: none;
    will-change: transform;
    transform: translateZ(0);
}

/* === Ambient neon glow (formerly cloud/fog) ===
   Two corner radial gradients in primary/secondary neon — gives the void
   subtle depth. Visible only in night scene. */
.scene-glow {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 2;
    opacity: 0;
    transition: opacity 0.4s ease;
    background:
        radial-gradient(ellipse 60% 50% at 15% 10%, var(--neon-glow) 0%, transparent 65%),
        radial-gradient(ellipse 55% 45% at 88% 92%, var(--neon-glow-2) 0%, transparent 65%);
    mix-blend-mode: screen;
}

[data-scene="night"] .scene-glow {
    opacity: 0.55;
}
[data-scene="sunny"] .scene-glow {
    opacity: 0.35;
    mix-blend-mode: multiply;
}

/* === Footer === */
.site-footer {
    position: relative;
    z-index: 10;
    padding: 2rem 0;
    text-align: center;
    color: var(--mid);
    font-size: 0.82rem;
    border-top: 1px solid var(--line);
    transition:
        border-color 0.3s ease,
        color 0.3s ease;
}

.footer-line {
    font-family: var(--font-mono);
    display: inline-flex;
    flex-wrap: wrap;
    align-items: baseline;
    justify-content: center;
    gap: 0.5rem;
}

.footer-line.secondary { margin-top: 0.4rem; }


/* === Selection === */
[data-scene="sunny"] ::selection {
    background: #a8b2c0;
    color: var(--text);
}
[data-scene="night"] ::selection {
    background: #3d4f6a;
    color: var(--text);
}

/* === Custom Scrollbar === */
* {
    scrollbar-width: thin;
    scrollbar-color: var(--line) transparent;
}
*::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}
*::-webkit-scrollbar-track { background: transparent; }
*::-webkit-scrollbar-thumb {
    background: var(--line);
    border-radius: 4px;
    transition: background 0.2s ease;
}
*::-webkit-scrollbar-thumb:hover {
    background: var(--accent);
    box-shadow: 0 0 8px var(--neon-glow);
}

/* === Image Zoom === */
.img-zoom-overlay {
    position: fixed;
    inset: 0;
    z-index: 10000;
    background: rgba(0, 0, 0, 0);
    backdrop-filter: blur(0px);
    display: flex;
    align-items: center;
    justify-content: center;
    cursor: zoom-out;
    opacity: 0;
    transition: opacity 0.25s ease, background 0.3s ease, backdrop-filter 0.3s ease;
}

.img-zoom-overlay.open {
    opacity: 1;
    background: rgba(0, 0, 0, 0.6);
    backdrop-filter: blur(8px);
}

.img-zoom-image {
    max-width: 90vw;
    max-height: 90vh;
    border-radius: 6px;
    box-shadow: 0 8px 32px rgba(0, 0, 0, 0.3);
    transform: scale(0.92);
    transition: transform 0.3s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.img-zoom-overlay.open .img-zoom-image {
    transform: scale(1);
}

/* === Encrypted Content === */
.encrypt-locked {
    text-align: center;
    padding: 3rem 1.5rem;
    border: 1px dashed var(--line);
    border-radius: 6px;
    transition: border-color 0.3s ease;
}

.encrypt-prompt svg {
    color: var(--mid);
    margin-bottom: 1rem;
}

.encrypt-hint {
    color: var(--mid);
    font-size: 0.9rem;
    margin-bottom: 1.2rem;
}

.encrypt-form {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
}

.encrypt-input {
    font-family: inherit;
    font-size: 0.88rem;
    padding: 0.4em 0.8em;
    border: 1px solid var(--line);
    border-radius: 4px;
    background: var(--bg);
    color: var(--text);
    outline: none;
    width: 200px;
    transition: border-color 0.2s ease, background-color 0.3s ease, color 0.3s ease;
}

.encrypt-input:focus {
    border-color: var(--mid);
}

.encrypt-btn {
    font-family: inherit;
    font-size: 0.85rem;
    padding: 0.4em 1em;
    border: 1px solid var(--line);
    border-radius: 4px;
    background: none;
    color: var(--mid);
    cursor: pointer;
    transition: border-color 0.2s ease, color 0.2s ease;
}

.encrypt-btn:hover {
    border-color: var(--mid);
    color: var(--text);
}

.encrypt-error {
    color: #c44;
    font-size: 0.82rem;
    margin-top: 0.8rem;
}

/* === Waline Comment Overrides === */
#waline-comment {
    --waline-bg-color: transparent;
    --waline-bg-color-light: var(--line);
    --waline-bg-color-hover: var(--line);
    --waline-border-color: var(--line);
    --waline-disable-bg-color: var(--line);
    --waline-color: var(--text);
    --waline-active-color: var(--accent);
    --waline-theme-color: var(--accent);
    --waline-font-size: 0.9rem;
    --waline-border: 1px solid var(--line);
    --waline-avatar-size: 2.5rem;
    margin-top: 2rem;
}

.post-views {
    color: var(--mid);
}

/* === 404 (terminal style) === */
.error-page {
    padding: 8rem 0 3rem;
}

.error-terminal {
    max-width: 640px;
    margin: 0 auto;
    font-family: var(--font-mono);
    background: color-mix(in srgb, var(--surface-1) 60%, transparent);
    border: 1px solid var(--line);
    border-radius: 10px;
    padding: 1.4rem 1.5rem;
    box-shadow: 0 24px 60px rgba(0, 0, 0, 0.25), 0 0 0 1px var(--neon-glow);
}

.error-term-line {
    display: flex;
    align-items: baseline;
    gap: 0.6rem;
    font-size: 0.92rem;
    line-height: 1.7;
}

.error-term-prompt {
    color: var(--accent);
    font-weight: 700;
    text-shadow: 0 0 10px var(--neon-glow);
}

.error-term-cmd { color: var(--text); }

.error-term-out {
    color: var(--mid);
    font-size: 0.88rem;
    margin: 0.2rem 0 1.1rem;
    line-height: 1.7;
}

.error-term-cursor {
    display: inline-block;
    width: 0.55em;
    height: 1.05em;
    vertical-align: text-bottom;
    background: var(--accent);
    box-shadow: 0 0 10px var(--neon-glow);
    animation: terminal-blink 1.1s steps(1) infinite;
}

.error-actions {
    display: flex;
    gap: 0.75rem;
    flex-wrap: wrap;
    margin-top: 1.5rem;
}

.error-link {
    font-size: 0.88rem;
    color: var(--mid);
    border: 1px solid var(--line);
    padding: 0.4em 1em;
    border-radius: 6px;
    transition: color 0.2s ease, border-color 0.2s ease;
}

.error-link:hover {
    color: var(--text);
    border-color: var(--mid);
}

.error-search-btn {
    font-size: 0.88rem;
    font-family: inherit;
    color: var(--bg);
    background: var(--accent);
    border: none;
    padding: 0.4em 1.1em;
    border-radius: 6px;
    cursor: pointer;
    transition: opacity 0.2s ease;
}

.error-search-btn:hover {
    opacity: 0.8;
}

.error-recent {
    max-width: 600px;
    margin: 0 auto;
    padding-bottom: 5rem;
}

.error-recent-title {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.06em;
    color: var(--mid);
    font-weight: 400;
    margin-bottom: 1.25rem;
    text-align: center;
}

/* === Shared list-page header (archive / timeline / interests / links) === */
.list-header {
    padding: 20px 0 2.5rem;
}

.list-eyebrow {
    display: block;
    font-family: var(--font-mono);
    font-size: 0.78rem;
    letter-spacing: 0.06em;
    color: var(--accent);
    margin-bottom: 0.5rem;
}

.list-title {
    font-family: var(--font-display);
    font-size: clamp(2rem, 4vw, 2.8rem);
    font-weight: 700;
    letter-spacing: -0.035em;
    margin: 0;
}

.list-desc {
    color: var(--mid);
    font-size: 0.95rem;
    max-width: 640px;
    margin: 0.6rem 0 0;
}

/* Modifier for single-post header: keep the 20px top padding but add the post-only
   bottom divider that separates the meta row from the article body. */
.list-header--post {
    padding-bottom: 1.8rem;
    border-bottom: 1px solid var(--line);
    margin-bottom: 2.2rem;
    transition: border-color 0.3s ease;
}

/* === Shared pill buttons (archive tag filter / timeline tag filter / timeline toggle) === */
.archive-tag,
.tl-tag,
.tl-toggle-hidden {
    font-family: var(--font-mono);
    font-size: 0.78rem;
    color: var(--text);
    background: color-mix(in srgb, var(--surface-1) 75%, transparent);
    border: 1px solid color-mix(in srgb, var(--accent) 30%, var(--line));
    border-radius: 999px;
    padding: 0.22em 0.7em;
    cursor: pointer;
    transition:
        border-color 0.2s ease,
        color 0.2s ease,
        background-color 0.2s ease,
        box-shadow 0.2s ease;
}

.archive-tag:hover,
.tl-tag:hover,
.tl-toggle-hidden:hover {
    border-color: var(--accent);
    color: var(--accent);
    background: color-mix(in srgb, var(--accent) 10%, transparent);
    box-shadow: 0 0 0 1px var(--neon-glow);
}

.archive-tag.active,
.tl-tag.active,
.tl-toggle-hidden.active {
    color: var(--bg);
    background: var(--accent);
    border-color: var(--accent);
    box-shadow: 0 0 10px var(--neon-glow);
}

/* Night scene: dim down the active fill since --accent #00d9ff is brighter than day */
[data-scene="night"] .archive-tag.active,
[data-scene="night"] .tl-tag.active,
[data-scene="night"] .tl-toggle-hidden.active {
    background: color-mix(in srgb, var(--accent) 86%, #000);
    border-color: color-mix(in srgb, var(--accent) 86%, #000);
    box-shadow: 0 0 9px color-mix(in srgb, var(--neon-glow) 80%, transparent);
}

/* === Shared inline tag chips (archive post item / timeline entry) === */
.chip,
.tl-entry-tag {
    font-family: var(--font-mono);
    font-size: 0.7rem;
    letter-spacing: 0.04em;
    color: var(--mid);
    background: color-mix(in srgb, var(--surface-1) 70%, transparent);
    border: 1px solid var(--line);
    border-radius: 999px;
    padding: 0.15em 0.55em;
    transition: color 0.2s ease, border-color 0.2s ease;
}

/* === Shared card tag (interests cards / links cards) ===
   Highlight uses accent color + soft neon-glow so the tag never blends into
   the card border. */
.interest-tag,
.link-tag {
    font-family: var(--font-mono);
    font-size: 0.74rem;
    font-weight: 700;
    letter-spacing: 0.04em;
    color: var(--text);
    background: color-mix(in srgb, var(--surface-1) 70%, transparent);
    border: 1px solid var(--line);
    border-radius: 4px;
    padding: 0.1em 0.55em;
    flex-shrink: 0;
    transition: border-color 0.3s ease, color 0.3s ease, background-color 0.3s ease;
    /* Frost glass: blur whatever sits behind the tag (card bg image, page bg)
       so the tag never blends into a noisy underlay. */
    backdrop-filter: blur(8px) saturate(1.4);
    -webkit-backdrop-filter: blur(8px) saturate(1.4);
}

.interest-card:hover .interest-tag,
.link-card:hover .link-tag {
    border-color: var(--accent);
    color: var(--accent);
}

/* === Mobile: encrypt form stacks vertically (≤480px) ===
   Two-item flex row (input + button) overflows very narrow screens. */
@media (max-width: 480px) {
    .encrypt-form {
        flex-direction: column;
        align-items: center;
    }
    .encrypt-input {
        width: 100%;
        max-width: 240px;
    }
}
/* === Site Header — glass / scrolled-shrink ===
   header sticks to top, backdrop-blurs the content beneath it,
   and shrinks (height + padding) once `.is-scrolled` is added by JS. */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: color-mix(in srgb, var(--bg) 55%, transparent);
  backdrop-filter: blur(18px) saturate(160%);
  -webkit-backdrop-filter: blur(18px) saturate(160%);
  border-bottom: 1px solid var(--line);
  transition:
    background-color 0.3s ease,
    border-color 0.3s ease,
    box-shadow 0.3s ease;
}

.site-header.is-scrolled {
  background: color-mix(in srgb, var(--bg) 78%, transparent);
  box-shadow: 0 1px 0 var(--line), 0 12px 32px -20px var(--neon-glow);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.4rem;
  height: 64px;
  max-width: var(--header-width, 1000px);
  margin: 0 auto;
  padding: 0 1.5rem;
  transition: height 0.25s ease;
}

.site-header.is-scrolled .header-inner { height: 52px; }

/* === Brand / logo on the left === */
.site-brand {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-weight: 600;
  letter-spacing: 0.01em;
  font-size: 1rem;
  color: var(--text);
  text-decoration: none;
  line-height: 1;
}
.site-brand:hover { color: var(--text); text-shadow: 0 0 14px var(--neon-glow); }
.site-brand .brand-dot {
  display: inline-block;
  width: 8px; height: 8px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 12px var(--neon-glow);
  transform: translateY(-1px);
}

/* Terminal cursor blinking after the brand name — sits flush against the
   brand text (negative margin cancels the flex gap) and is vertically
   centered with the mono cap height */
.brand-cursor {
  display: inline-block;
  width: 0.5em;
  height: 1em;
  margin-left: calc(0.1em - 0.5rem);
  background: var(--accent);
  box-shadow: 0 0 8px var(--neon-glow);
  animation: brand-blink 1.1s steps(1) infinite;
}

@keyframes brand-blink {
  0%, 50% { opacity: 1; }
  50.01%, 100% { opacity: 0; }
}

@media (prefers-reduced-motion: reduce) {
  .brand-cursor { animation: none; opacity: 1; }
}

/* === Nav links — slide-in neon underline === */
.site-nav {
  display: flex;
  gap: 1.4rem;
  margin-left: auto;
}

.nav-link {
  position: relative;
  font-family: var(--font-body);
  font-size: 0.86rem;
  font-weight: 500;
  color: var(--mid);
  letter-spacing: 0.01em;
  padding: 0.25em 0;
  transition: color 0.2s ease;
}

.nav-link::after {
  content: '';
  position: absolute;
  left: 0; right: 0; bottom: -2px;
  height: 1.5px;
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  box-shadow: 0 0 10px var(--neon-glow);
  transform: scaleX(0);
  transform-origin: left center;
  transition: transform 0.28s cubic-bezier(0.22, 1, 0.36, 1);
}

.nav-link:hover { color: var(--text); }
.nav-link:hover::after,
.nav-link.is-active::after { transform: scaleX(1); }

.nav-link.is-active { color: var(--text); }

/* === Header action buttons (search, scene, picker, ...) === */
.header-actions {
  display: flex;
  align-items: center;
  gap: 0.4rem;
}

.search-btn,
.travelling-btn,
.scene-toggle,
.particle-picker-btn,
.music-btn {
  background: color-mix(in srgb, var(--surface-1) 70%, transparent);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 7px;
  cursor: pointer;
  color: var(--mid);
  display: flex;
  align-items: center;
  justify-content: center;
  transition:
    color 0.2s ease,
    border-color 0.2s ease,
    background-color 0.2s ease,
    box-shadow 0.2s ease;
  line-height: 0;
}

.search-btn:hover,
.travelling-btn:hover,
.scene-toggle:hover,
.particle-picker-btn:hover,
.music-btn:hover {
  color: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 0 1px var(--neon-glow), 0 0 18px -2px var(--neon-glow);
}

/* === Music player === */
.music-btn.is-playing {
  color: var(--accent);
  border-color: color-mix(in srgb, var(--accent) 60%, transparent);
  box-shadow: 0 0 0 1px var(--neon-glow), 0 0 18px -2px var(--neon-glow);
}

.music-btn.is-playing svg {
  animation: music-float 1.8s ease-in-out infinite;
}

@keyframes music-float {
  0%, 100% { transform: translateY(0); }
  50%       { transform: translateY(-2px); }
}

@media (prefers-reduced-motion: reduce) {
  .music-btn.is-playing svg { animation: none; }
}

/* === Particle picker dropdown === */
.particle-picker { position: relative; display: flex; }

.particle-dropdown {
  position: absolute;
  top: calc(100% + 8px);
  right: 0;
  background: color-mix(in srgb, var(--surface-1) 92%, transparent);
  backdrop-filter: blur(14px) saturate(160%);
  -webkit-backdrop-filter: blur(14px) saturate(160%);
  border: 1px solid var(--line);
  border-radius: 8px;
  padding: 4px;
  min-width: 120px;
  opacity: 0;
  pointer-events: none;
  transform: translateY(-4px);
  transition:
    opacity 0.2s ease,
    transform 0.2s ease,
    background-color 0.3s ease,
    border-color 0.3s ease;
  box-shadow: 0 12px 36px -10px rgba(0, 0, 0, 0.45),
              0 0 0 1px var(--line);
}

.particle-dropdown::before {
  content: '';
  position: absolute;
  top: -8px;
  left: 0;
  right: 0;
  height: 8px;
}

.particle-picker:hover .particle-dropdown {
  opacity: 1;
  pointer-events: auto;
  transform: translateY(0);
}

.particle-option {
  display: flex;
  align-items: center;
  gap: 0.55rem;
  width: 100%;
  padding: 7px 11px;
  background: none;
  border: none;
  border-radius: 5px;
  cursor: pointer;
  font-size: 0.82rem;
  font-family: var(--font-body);
  color: var(--mid);
  transition: background-color 0.15s ease, color 0.15s ease;
  line-height: 1;
}

.particle-option:hover {
  background: color-mix(in srgb, var(--accent) 12%, transparent);
  color: var(--text);
}

.particle-option.active {
  color: var(--accent);
  font-weight: 500;
}

[data-scene="sunny"] .icon-sun { display: block; }
[data-scene="sunny"] .icon-night { display: none; }
[data-scene="night"] .icon-sun { display: none; }
[data-scene="night"] .icon-night { display: block; }

/* === Search Overlay === */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0, 0, 0, 0);
  backdrop-filter: blur(0px);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 15vh;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, background 0.3s ease, backdrop-filter 0.3s ease;
}

.search-overlay.open {
  opacity: 1;
  pointer-events: auto;
  background: rgba(0, 0, 0, 0.5);
  backdrop-filter: blur(8px);
}

.search-container {
  width: 100%;
  max-width: 620px;
  margin: 0 1rem;
  background: var(--surface-1);
  border: 1px solid var(--line);
  border-radius: 10px;
  overflow: hidden;
  box-shadow:
    0 24px 60px rgba(0, 0, 0, 0.45),
    0 0 0 1px var(--neon-glow);
  transform: scale(0.96) translateY(-12px);
  opacity: 0;
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1),
              opacity 0.25s ease,
              background-color 0.3s ease, border-color 0.3s ease;
}

.search-overlay.open .search-container {
  transform: scale(1) translateY(0);
  opacity: 1;
}

.search-input-wrap {
  display: flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.9rem 1.1rem;
  border-bottom: 1px solid var(--line);
  color: var(--mid);
  transition: border-color 0.3s ease;
}

.search-input {
  flex: 1;
  background: none;
  border: none;
  outline: none;
  font-size: 0.95rem;
  color: var(--text);
  font-family: var(--font-mono);
}

.search-prompt {
  font-family: var(--font-mono);
  font-size: 1rem;
  font-weight: 600;
  color: var(--accent);
  text-shadow: 0 0 10px var(--neon-glow);
  line-height: 1;
  user-select: none;
}

.search-input::placeholder { color: var(--mid); }

.search-kbd {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 0.18em 0.5em;
  border: 1px solid var(--line);
  border-radius: 4px;
  color: var(--mid);
  line-height: 1;
}

.search-results {
  max-height: 50vh;
  overflow-y: auto;
}

.search-result-item {
  display: block;
  padding: 0.75rem 1.1rem;
  border-bottom: 1px solid var(--line);
  text-decoration: none;
  transition: background-color 0.15s ease, padding 0.15s ease;
}

.search-result-item:hover {
  background: color-mix(in srgb, var(--accent) 8%, transparent);
  padding-left: 1.5rem;
}

.search-result-item:last-child {
  border-bottom: none;
}

.search-result-title {
  font-family: var(--font-display);
  font-size: 0.95rem;
  color: var(--text);
  font-weight: 600;
  margin-bottom: 0.2rem;
}

.search-result-meta {
  font-family: var(--font-mono);
  font-size: 0.74rem;
  color: var(--mid);
  letter-spacing: 0.02em;
}

.search-result-snippet {
  font-size: 0.82rem;
  color: var(--mid);
  margin-top: 0.25rem;
  line-height: 1.5;
}

.search-empty {
  padding: 2rem 1rem;
  text-align: center;
  color: var(--mid);
  font-size: 0.88rem;
}

/* === Mobile: scrollable nav (≤720px) ===
   Keep single-row layout; nav becomes a horizontally scrollable strip
   rather than wrapping or overflowing — no JS or hamburger needed. */
@media (max-width: 720px) {
  .header-inner {
    justify-content: flex-start;
    gap: 0.5rem;
    padding: 0 1rem;
  }

  .site-nav {
    flex: 1;
    min-width: 0;
    margin-left: 0;
    gap: 0.8rem;
    overflow-x: auto;
    scrollbar-width: none;
    -webkit-overflow-scrolling: touch;
  }

  .site-nav::-webkit-scrollbar { display: none; }

  .nav-link {
    white-space: nowrap;
    flex-shrink: 0;
    font-size: 0.8rem;
  }
}

/* === Very small screens (≤480px) === */
@media (max-width: 480px) {
  .header-inner {
    padding: 0 0.8rem;
    gap: 0.4rem;
  }

  /* Particle picker is non-essential on very small viewports */
  .particle-picker { display: none; }

  /* Give search container breathing room */
  .search-container { margin: 0 0.75rem; }
}
/* === Code Syntax Highlighting ===
   Cyber palette: cyan (types/builtins) + violet (keywords/numbers)
                  + magenta (functions/operators) + amber (strings) */

/* ---------- Sunny (light) ---------- */
[data-scene="sunny"] .bg,
[data-scene="sunny"] .chroma {
    color: var(--text);
    background-color: var(--surface-2);
}
[data-scene="sunny"] .chroma .err { color: #d4344e; background: transparent; }
[data-scene="sunny"] .chroma .lnlinks { outline: none; text-decoration: none; color: inherit; }
[data-scene="sunny"] .chroma .lntd { vertical-align: top; padding: 0; margin: 0; border: 0; }
[data-scene="sunny"] .chroma .lntable { border-spacing: 0; padding: 0; margin: 0; border: 0; }
[data-scene="sunny"] .chroma .hl { background-color: rgba(0, 153, 184, 0.10); }
[data-scene="sunny"] .chroma .lnt,
[data-scene="sunny"] .chroma .ln {
    white-space: pre; -webkit-user-select: none; user-select: none;
    margin-right: 0.4em; padding: 0 0.4em;
    color: #94a3b8;
}
[data-scene="sunny"] .chroma .line { display: flex; }

/* keywords - violet */
[data-scene="sunny"] .chroma .k,
[data-scene="sunny"] .chroma .kc,
[data-scene="sunny"] .chroma .kd,
[data-scene="sunny"] .chroma .kn,
[data-scene="sunny"] .chroma .kp,
[data-scene="sunny"] .chroma .kr { color: #7c3aed; }
/* types - cyan */
[data-scene="sunny"] .chroma .kt,
[data-scene="sunny"] .chroma .no { color: #0891b2; }
/* names */
[data-scene="sunny"] .chroma .n,
[data-scene="sunny"] .chroma .ni,
[data-scene="sunny"] .chroma .nl,
[data-scene="sunny"] .chroma .nn,
[data-scene="sunny"] .chroma .py { color: var(--text); }
/* functions / methods - magenta */
[data-scene="sunny"] .chroma .nf,
[data-scene="sunny"] .chroma .fm,
[data-scene="sunny"] .chroma .nd { color: #db2777; }
/* classes / attrs - cyan */
[data-scene="sunny"] .chroma .nc,
[data-scene="sunny"] .chroma .na,
[data-scene="sunny"] .chroma .ne,
[data-scene="sunny"] .chroma .nx { color: #0891b2; }
/* builtins - cyan italic */
[data-scene="sunny"] .chroma .nb,
[data-scene="sunny"] .chroma .bp,
[data-scene="sunny"] .chroma .nv,
[data-scene="sunny"] .chroma .vc,
[data-scene="sunny"] .chroma .vg,
[data-scene="sunny"] .chroma .vi,
[data-scene="sunny"] .chroma .vm { color: #0891b2; font-style: italic; }
/* tags - violet */
[data-scene="sunny"] .chroma .nt { color: #7c3aed; }
/* strings - amber */
[data-scene="sunny"] .chroma .l,
[data-scene="sunny"] .chroma .ld,
[data-scene="sunny"] .chroma .s,
[data-scene="sunny"] .chroma .sa,
[data-scene="sunny"] .chroma .sb,
[data-scene="sunny"] .chroma .sc,
[data-scene="sunny"] .chroma .dl,
[data-scene="sunny"] .chroma .sd,
[data-scene="sunny"] .chroma .s2,
[data-scene="sunny"] .chroma .sh,
[data-scene="sunny"] .chroma .si,
[data-scene="sunny"] .chroma .sx,
[data-scene="sunny"] .chroma .sr,
[data-scene="sunny"] .chroma .s1,
[data-scene="sunny"] .chroma .ss { color: #b45309; }
[data-scene="sunny"] .chroma .se { color: #db2777; }
/* numbers - violet */
[data-scene="sunny"] .chroma .m,
[data-scene="sunny"] .chroma .mb,
[data-scene="sunny"] .chroma .mf,
[data-scene="sunny"] .chroma .mh,
[data-scene="sunny"] .chroma .mi,
[data-scene="sunny"] .chroma .il,
[data-scene="sunny"] .chroma .mo { color: #7c3aed; }
/* operators - magenta */
[data-scene="sunny"] .chroma .o,
[data-scene="sunny"] .chroma .ow { color: #db2777; }
/* punctuation */
[data-scene="sunny"] .chroma .p { color: var(--mid); }
/* comments - dim italic */
[data-scene="sunny"] .chroma .c,
[data-scene="sunny"] .chroma .ch,
[data-scene="sunny"] .chroma .cm,
[data-scene="sunny"] .chroma .c1,
[data-scene="sunny"] .chroma .cs,
[data-scene="sunny"] .chroma .cp,
[data-scene="sunny"] .chroma .cpf { color: #94a3b8; font-style: italic; }
[data-scene="sunny"] .chroma .ge { font-style: italic; }
[data-scene="sunny"] .chroma .gs { font-weight: bold; }

/* ---------- Night (dark, cyber neon) ---------- */
[data-scene="night"] .bg,
[data-scene="night"] .chroma {
    color: var(--text);
    background-color: var(--surface-2);
}
[data-scene="night"] .chroma .err { color: #ff5c7c; background: transparent; }
[data-scene="night"] .chroma .lnlinks { outline: none; text-decoration: none; color: inherit; }
[data-scene="night"] .chroma .lntd { vertical-align: top; padding: 0; margin: 0; border: 0; }
[data-scene="night"] .chroma .lntable { border-spacing: 0; padding: 0; margin: 0; border: 0; }
[data-scene="night"] .chroma .hl { background-color: rgba(0, 217, 255, 0.08); }
[data-scene="night"] .chroma .lnt,
[data-scene="night"] .chroma .ln {
    white-space: pre; -webkit-user-select: none; user-select: none;
    margin-right: 0.4em; padding: 0 0.4em;
    color: #4a5568;
}
[data-scene="night"] .chroma .line { display: flex; }

/* keywords - violet */
[data-scene="night"] .chroma .k,
[data-scene="night"] .chroma .kc,
[data-scene="night"] .chroma .kd,
[data-scene="night"] .chroma .kn,
[data-scene="night"] .chroma .kp,
[data-scene="night"] .chroma .kr { color: #b66dff; }
/* types - cyan */
[data-scene="night"] .chroma .kt,
[data-scene="night"] .chroma .no { color: #00d9ff; }
/* names - light */
[data-scene="night"] .chroma .n,
[data-scene="night"] .chroma .ni,
[data-scene="night"] .chroma .nl,
[data-scene="night"] .chroma .nn,
[data-scene="night"] .chroma .py { color: var(--text); }
/* functions / methods - magenta */
[data-scene="night"] .chroma .nf,
[data-scene="night"] .chroma .fm,
[data-scene="night"] .chroma .nd { color: #ff6dd8; }
/* classes / attrs - cyan */
[data-scene="night"] .chroma .nc,
[data-scene="night"] .chroma .na,
[data-scene="night"] .chroma .ne,
[data-scene="night"] .chroma .nx { color: #00d9ff; }
/* builtins - cyan italic */
[data-scene="night"] .chroma .nb,
[data-scene="night"] .chroma .bp,
[data-scene="night"] .chroma .nv,
[data-scene="night"] .chroma .vc,
[data-scene="night"] .chroma .vg,
[data-scene="night"] .chroma .vi,
[data-scene="night"] .chroma .vm { color: #00d9ff; font-style: italic; }
/* tags - violet */
[data-scene="night"] .chroma .nt { color: #b66dff; }
/* strings - amber */
[data-scene="night"] .chroma .l,
[data-scene="night"] .chroma .ld,
[data-scene="night"] .chroma .s,
[data-scene="night"] .chroma .sa,
[data-scene="night"] .chroma .sb,
[data-scene="night"] .chroma .sc,
[data-scene="night"] .chroma .dl,
[data-scene="night"] .chroma .sd,
[data-scene="night"] .chroma .s2,
[data-scene="night"] .chroma .sh,
[data-scene="night"] .chroma .si,
[data-scene="night"] .chroma .sx,
[data-scene="night"] .chroma .sr,
[data-scene="night"] .chroma .s1,
[data-scene="night"] .chroma .ss { color: #f5d68a; }
[data-scene="night"] .chroma .se { color: #ff6dd8; }
/* numbers - violet */
[data-scene="night"] .chroma .m,
[data-scene="night"] .chroma .mb,
[data-scene="night"] .chroma .mf,
[data-scene="night"] .chroma .mh,
[data-scene="night"] .chroma .mi,
[data-scene="night"] .chroma .il,
[data-scene="night"] .chroma .mo { color: #b66dff; }
/* operators - magenta */
[data-scene="night"] .chroma .o,
[data-scene="night"] .chroma .ow { color: #ff6dd8; }
/* punctuation - dim */
[data-scene="night"] .chroma .p { color: var(--mid); }
/* comments - dim italic */
[data-scene="night"] .chroma .c,
[data-scene="night"] .chroma .ch,
[data-scene="night"] .chroma .cm,
[data-scene="night"] .chroma .c1,
[data-scene="night"] .chroma .cs { color: #5a657a; font-style: italic; }
[data-scene="night"] .chroma .cp,
[data-scene="night"] .chroma .cpf { color: #b66dff; }
/* diff */
[data-scene="night"] .chroma .gd { color: #ff5c7c; }
[data-scene="night"] .chroma .gi { color: #7eff9a; font-weight: bold; }
[data-scene="night"] .chroma .go { color: #5a657a; }
[data-scene="night"] .chroma .ge { text-decoration: underline; }
[data-scene="night"] .chroma .gh { font-weight: bold; }
[data-scene="night"] .chroma .gu { font-weight: bold; }
[data-scene="night"] .chroma .gl { text-decoration: underline; }
/*
  intro-overlay — first-load splash overlay (SAO-inspired).
  Rendered by layouts/partials/intro-overlay.html, controlled per-page
  via .Params.intro frontmatter. Color palette is intentionally neutral
  (black/white) so it does not clash with the theme accent system.
*/

.intro-overlay {
  position: fixed;
  inset: 0;
  z-index: 9999;
  background: rgba(0, 0, 0, 0.3);
  backdrop-filter: blur(4px);
  -webkit-backdrop-filter: blur(4px);
  color: #fff;
  display: flex;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono, "JetBrains Mono", "SF Mono", "Cascadia Code", Consolas, monospace);
  /* --intro-end set inline by the partial based on frontmatter line count */
  animation: intro-overlay-out 0.56s ease var(--intro-end, 3.08s) forwards;
}
.intro-overlay.is-gone {
  animation: intro-overlay-out 0.32s ease forwards;
}
/* Cooldown skip: hide instantly with no animation, element takes no space */
.intro-overlay.is-skip {
  display: none;
}
@keyframes intro-overlay-out {
  to { opacity: 0; visibility: hidden; pointer-events: none; }
}

.intro-stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.4rem;
}

.intro-inner {
  /* width follows the widest child (welcome line); divider matches it */
  width: max-content;
  max-width: min(720px, 90vw);
  text-align: center;
}

.intro-welcome {
  margin: 0 0 0.5rem;
  font-size: clamp(1.5rem, 4.5vw, 3rem);
  font-weight: 700;
  letter-spacing: 0.05em;
  color: #fff;
  text-shadow: 0 0 20px rgba(255, 255, 255, 0.55);
  opacity: 0;
  transform: scale(0.85);
  animation: intro-welcome-in 0.49s ease 0.07s forwards;
  white-space: nowrap;
}
@keyframes intro-welcome-in {
  to { opacity: 1; transform: scale(1); }
}

.intro-divider {
  height: 10px;
  width: 0;
  margin: 0 auto 1.5rem;
  background: rgba(255, 255, 255, 0.7);
  box-shadow: 0 0 18px rgba(255, 255, 255, 0.55);
  animation: intro-divider-sweep 0.35s ease 0.49s forwards;
}
@keyframes intro-divider-sweep {
  to { width: 100%; }
}

.intro-msg {
  /* fixed narrow width, independent of welcome length */
  width: 380px;
  max-width: 90vw;
  margin-top: 0.35rem;
  border: 1px solid rgba(255, 255, 255, 0.7);
  border-radius: 4px;
  background: rgba(220, 224, 230, 0.18);
  text-align: left;
  opacity: 0;
  transform: translateY(8px);
  animation: intro-msg-in 0.35s ease 0.7s forwards;
  box-shadow: 0 0 24px rgba(255, 255, 255, 0.1), inset 0 0 0 1px rgba(0, 0, 0, 0.35);
}
@keyframes intro-msg-in {
  to { opacity: 1; transform: translateY(0); }
}

.intro-msg-head {
  background: rgba(255, 255, 255, 0.85);
  color: #000;
  font-size: 0.74rem;
  letter-spacing: 0.4em;
  padding: 0.45rem 1rem;
  font-weight: 600;
  text-align: center;
  border-radius: 3px 3px 0 0;
}

.intro-msg-body {
  padding: 1.1rem 1.2rem 1.2rem;
}

.intro-msg-body p {
  margin: 0 0 0.4rem;
  font-size: 0.92rem;
  letter-spacing: 0.05em;
  color: #fff;
  opacity: 0;
  animation: intro-line-in 0.28s ease forwards;
  /* per-line animation-delay set inline by the partial */
  white-space: normal;
  word-break: break-word;
}
.intro-msg-body p:last-child { margin-bottom: 0; }
@keyframes intro-line-in {
  to { opacity: 1; }
}

.intro-msg-sign {
  margin-top: 0.8rem !important;
  font-size: 0.78rem !important;
  text-align: right;
  letter-spacing: 0.1em;
  color: rgba(255, 255, 255, 0.7) !important;
}

.intro-skip {
  position: absolute;
  bottom: 1.5rem;
  right: 1.5rem;
  background: transparent;
  color: rgba(255, 255, 255, 0.4);
  border: 1px solid rgba(255, 255, 255, 0.25);
  padding: 0.5em 1.2em;
  font: inherit;
  font-size: 0.72rem;
  letter-spacing: 0.18em;
  cursor: pointer;
  transition: color 0.2s ease, border-color 0.2s ease;
  opacity: 0;
  animation: intro-line-in 0.28s ease 0.63s forwards;
}
.intro-skip:hover {
  color: #fff;
  border-color: #fff;
}

/* === Mobile: prevent welcome text overflow (≤480px) ===
   `white-space: nowrap` on the welcome heading can overflow narrow screens
   when the text is long. Allow wrapping and shrink the message box to fit. */
@media (max-width: 480px) {
  .intro-welcome {
    white-space: normal;
    word-break: break-word;
  }

  .intro-msg {
    width: calc(100vw - 3rem);
    max-width: calc(100vw - 3rem);
  }
}

/* === Reduced motion: skip all keyframe animations === */
@media (prefers-reduced-motion: reduce) {
  .intro-overlay { animation: none; }
  .intro-welcome { animation: none; opacity: 1; transform: none; }
  .intro-divider { animation: none; width: 100%; }
  .intro-msg     { animation: none; opacity: 1; transform: none; }
  .intro-msg-body p { animation: none; opacity: 1; }
  .intro-skip    { animation: none; opacity: 1; }
}