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

/*
 * Theme variables:
 *   --bg       background
 *   --fg       main body text
 *   --fg-dim   secondary / muted text
 *   --heading  h1, h2, sidebar title, active nav
 *   --link     links, interactive highlights
 *   --border   sidebar border, theme-btn border
 */

:root,
[data-theme="oceanic"] {
    --fg: #C0C5CE;
    --fg-dim: #65737E;
    --heading: #FAC863;
    --link: #5FB3B3;
    --bg: #1B2B34;
    --border: #343D46;
    --sidebar-width: 220px;
    --font-mono: "Menlo", "Monaco", "Courier New", monospace;
}

[data-theme="terminal"] {
    --fg: #00FF00;
    --fg-dim: #00AA00;
    --heading: #33FF33;
    --link: #00FF00;
    --bg: #000000;
    --border: #003300;
}

[data-theme="amber"] {
    --fg: #FFB000;
    --fg-dim: #AA7500;
    --heading: #FFD166;
    --link: #FFB000;
    --bg: #1A1000;
    --border: #332200;
}

[data-theme="matrix"] {
    --fg: #00CC00;
    --fg-dim: #007700;
    --heading: #00FF41;
    --link: #00FF41;
    --bg: #0D0208;
    --border: #003B00;
}

[data-theme="cobalt"] {
    --fg: #E1E1E1;
    --fg-dim: #7DA3C4;
    --heading: #FFC600;
    --link: #0088FF;
    --bg: #002240;
    --border: #003366;
}

[data-theme="dracula"] {
    --fg: #F8F8F2;
    --fg-dim: #6272A4;
    --heading: #BD93F9;
    --link: #FF79C6;
    --bg: #282A36;
    --border: #44475A;
}

[data-theme="monokai"] {
    --fg: #F8F8F2;
    --fg-dim: #75715E;
    --heading: #F92672;
    --link: #66D9EF;
    --bg: #272822;
    --border: #3E3D32;
}

[data-theme="tokyo-night"] {
    --fg: #A9B1D6;
    --fg-dim: #565F89;
    --heading: #BB9AF7;
    --link: #7AA2F7;
    --bg: #1A1B26;
    --border: #292E42;
}

[data-theme="nord"] {
    --fg: #D8DEE9;
    --fg-dim: #4C566A;
    --heading: #88C0D0;
    --link: #81A1C1;
    --bg: #2E3440;
    --border: #3B4252;
}

[data-theme="catppuccin"] {
    --fg: #CDD6F4;
    --fg-dim: #6C7086;
    --heading: #CBA6F7;
    --link: #89B4FA;
    --bg: #1E1E2E;
    --border: #313244;
}

[data-theme="rose-pine"] {
    --fg: #E0DEF4;
    --fg-dim: #6E6A86;
    --heading: #EB6F92;
    --link: #9CCFD8;
    --bg: #191724;
    --border: #26233A;
}

[data-theme="gruvbox"] {
    --fg: #EBDBB2;
    --fg-dim: #928374;
    --heading: #FABD2F;
    --link: #83A598;
    --bg: #282828;
    --border: #3C3836;
}

[data-theme="oceanic"] {
    --fg: #C0C5CE;
    --fg-dim: #65737E;
    --heading: #FAC863;
    --link: #5FB3B3;
    --bg: #1B2B34;
    --border: #343D46;
}

[data-theme="solarized-dark"] {
    --fg: #839496;
    --fg-dim: #586E75;
    --heading: #B58900;
    --link: #268BD2;
    --bg: #002B36;
    --border: #073642;
}

[data-theme="solarized-light"] {
    --fg: #657B83;
    --fg-dim: #93A1A1;
    --heading: #B58900;
    --link: #268BD2;
    --bg: #FDF6E3;
    --border: #EEE8D5;
}

[data-theme="paper"] {
    --fg: #3B3B3B;
    --fg-dim: #8A8A8A;
    --heading: #1A1A1A;
    --link: #2255AA;
    --bg: #F5F0EB;
    --border: #D5CFC9;
}

[data-theme="ivory"] {
    --fg: #4A3C2A;
    --fg-dim: #8A7B67;
    --heading: #8B4513;
    --link: #6B4226;
    --bg: #FFFFF0;
    --border: #E0D8C0;
}

/* Base */
html, body {
    height: 100%;
    background: var(--bg);
    color: var(--fg);
    font-family: var(--font-mono);
    font-size: 15px;
    line-height: 1.6;
}

a {
    color: var(--link);
    text-decoration: none;
}

a:hover {
    color: var(--heading);
    text-decoration: underline;
}

/* Layout */
.layout {
    display: flex;
    min-height: 100vh;
}

/* Sidebar */
.sidebar {
    position: fixed;
    top: 0;
    left: 0;
    width: var(--sidebar-width);
    height: 100vh;
    padding: 2rem 1.25rem;
    display: flex;
    flex-direction: column;
    border-right: 1px solid var(--border);
    overflow-y: auto;
}

.sidebar-title {
    font-size: 1.1rem;
    font-weight: bold;
    color: var(--heading);
    margin-bottom: 0.25rem;
    text-decoration: none;
    display: block;
}

.sidebar-title:hover {
    text-decoration: none;
}

.sidebar-subtitle {
    font-size: 0.85rem;
    color: var(--fg-dim);
    margin-bottom: 1.75rem;
    line-height: 1.3;
}

.sidebar-nav {
    list-style: none;
}

.sidebar-nav li {
    margin-bottom: 0.5rem;
}

.sidebar-nav a {
    display: block;
    padding: 0.3rem 0.6rem;
    color: var(--fg-dim);
    text-decoration: none;
    border-radius: 6px;
    transition: color 0.15s, background 0.15s, box-shadow 0.15s;
}

.sidebar-nav a:hover {
    color: var(--link);
    text-decoration: none;
}

.sidebar-nav a.active {
    color: var(--heading);
    background: rgba(255, 255, 255, 0.07);
    border: 1px solid rgba(255, 255, 255, 0.12);
    box-shadow: 0 0 8px rgba(255, 255, 255, 0.06);
}

/* Dev-only capsule next to nav item labels */
.nav-dev-tag {
    display: inline-block;
    font-size: 0.55rem;
    font-weight: bold;
    letter-spacing: 0.05em;
    padding: 0.1em 0.45em;
    margin-left: 0.4em;
    border-radius: 8px;
    background: #7a6a99;
    color: #fff;
    vertical-align: middle;
}

.nav-icon {
    vertical-align: -2px;
    margin-right: 0.3em;
    opacity: 0.7;
    transition: opacity 0.15s;
}

.sidebar-nav a.active .nav-icon {
    opacity: 1;
}

/* Theme switcher */
.sidebar-bottom {
    margin-top: auto;
    padding-top: 1.5rem;
    display: flex;
    flex-direction: column;
    gap: 0.75rem;
}

.theme-grid {
    display: none; /* Hidden for now — switch to 'grid' to re-enable */
    grid-template-columns: repeat(4, 1fr);
    gap: 3px;
    max-width: 90px;
}

/* Admin button — icon when logged out, text when logged in */
.admin-btn {
    background: none;
    border: none;
    color: var(--fg-dim);
    font-family: var(--font-mono);
    font-size: 0.7rem;
    padding: 0.3rem;
    border-radius: 4px;
    cursor: pointer;
    align-self: flex-start;
    display: inline-flex;
    align-items: center;
    justify-content: center;
    transition: color 0.15s, background 0.15s, border-color 0.15s;
}

.admin-btn:hover {
    color: var(--link);
    background: rgba(255, 255, 255, 0.06);
}

.admin-btn svg {
    display: block;
}

/* Logged-in state: text button with border */
body.is-dev .admin-btn {
    border: 1px solid var(--border);
    padding: 0.3rem 0.75rem;
    background: none;
}

body.is-dev .admin-btn:hover {
    border-color: var(--link);
}

/* Dev-only content (hidden unless authenticated) */
.dev-only {
    display: none !important;
}

body.is-dev .dev-only {
    display: revert !important;
}

/* Login modal */
.login-modal {
    position: fixed;
    inset: 0;
    z-index: 2000;
    display: flex;
    align-items: center;
    justify-content: center;
}

.login-backdrop {
    position: absolute;
    inset: 0;
    background: rgba(0, 0, 0, 0.6);
}

.login-dialog {
    position: relative;
    background: var(--bg);
    border: 1px solid var(--border);
    border-radius: 8px;
    padding: 1.75rem;
    min-width: 440px;
    max-width: 90vw;
    box-shadow: 0 4px 30px rgba(0, 0, 0, 0.5);
    font-family: var(--font-mono);
}

.login-dialog h3 {
    margin: 0 0 0.5rem 0;
    color: var(--heading);
    font-size: 1rem;
}

.login-intro {
    font-style: italic;
    color: var(--fg-dim);
    font-size: 0.85rem;
    line-height: 1.45;
    margin: 0 0 1rem 0;
}

.login-dialog label {
    display: block;
    font-size: 0.8rem;
    color: var(--fg-dim);
    margin-top: 0.85rem;
    margin-bottom: 0.25rem;
}

.login-dialog input[type="text"],
.login-dialog input[type="password"] {
    width: 100%;
    padding: 0.5rem 0.6rem;
    background: var(--bg);
    border: 1px solid var(--border);
    color: var(--fg);
    font-family: var(--font-mono);
    font-size: 0.9rem;
    border-radius: 4px;
    box-sizing: border-box;
}

.login-dialog input[type="text"]:focus,
.login-dialog input[type="password"]:focus {
    outline: none;
    border-color: var(--link);
}

.login-error {
    color: #d66;
    font-size: 0.8rem;
    margin-top: 0.5rem;
    min-height: 1.2em;
}

.login-buttons {
    display: flex;
    gap: 0.5rem;
    justify-content: flex-end;
    margin-top: 1rem;
}

.login-dialog button {
    background: none;
    border: 1px solid var(--border);
    color: var(--fg);
    font-family: var(--font-mono);
    font-size: 0.85rem;
    padding: 0.35rem 0.9rem;
    border-radius: 4px;
    cursor: pointer;
    transition: color 0.15s, border-color 0.15s;
}

.login-dialog button[type="submit"] {
    border-color: var(--link);
    color: var(--link);
}

.login-dialog button:hover {
    color: var(--heading);
    border-color: var(--heading);
}

.theme-btn {
    aspect-ratio: 1;
    width: 100%;
    border: 1px solid var(--border);
    cursor: pointer;
    border-radius: 2px;
    padding: 0;
    transition: border-color 0.15s, transform 0.1s;
}

.theme-btn:hover {
    border-color: var(--heading);
    transform: scale(1.15);
}

.theme-btn.active {
    border: 2px solid var(--heading);
}

/* Hero section */
.hero {
    display: flex;
    align-items: flex-start;
    gap: 1.5rem;
    margin-bottom: 0.75rem;
}

.hero-text {
    flex: 1;
}

.hero-photo {
    width: 160px;
    height: auto;
    border-radius: 6px;
    border: 1px solid var(--border);
    flex-shrink: 0;
}

.hero h1 {
    margin-bottom: 0.25rem;
}

.ascii-figure {
    font-family: var(--font-mono);
    font-size: 1.5rem;
    line-height: 1.2;
    color: var(--fg);
    flex-shrink: 0;
}

/* Main content */
.main {
    margin-left: var(--sidebar-width);
    padding: 2rem 2.5rem;
    flex: 1;
    max-width: 780px;
}

.main h1 {
    font-size: 1.5rem;
    color: var(--heading);
    margin-bottom: 1.5rem;
}

.hero .main h1,
.hero h1 {
    margin-bottom: 0.25rem;
}

.hero p {
    margin-bottom: 0;
    line-height: 1.35;
}

.hero-text p + p {
    margin-top: 0.15rem;
}

.main h2 {
    font-size: 1.1rem;
    color: var(--heading);
    margin-top: 1.5rem;
    margin-bottom: 0.75rem;
}

.main p {
    margin-bottom: 0.75rem;
}

.main ul {
    list-style: none;
    margin-bottom: 0.75rem;
}

.main ul li::before {
    content: "\2022\a0";
    color: var(--fg-dim);
}

.main ol {
    margin-bottom: 0.75rem;
    padding-left: 2.5em;
    color: var(--fg-dim);
}

.main ol li {
    margin-bottom: 0.5rem;
    color: var(--fg);
}

/* Collapsible panels */
.main li:has(> details)::before {
    content: none;
}

.main details {
    margin-bottom: 0.25rem;
}

.main summary {
    cursor: pointer;
    color: var(--link);
    list-style: disclosure-closed;
}

.main details[open] > summary {
    list-style: disclosure-open;
}

.main summary:hover {
    color: var(--heading);
}

/* Section-level collapsible (h2 inside summary) */
.main > details {
    margin-top: 1.5rem;
}

.main > details > summary {
    list-style: disclosure-closed;
    color: var(--heading);
}

.main > details[open] > summary {
    list-style: disclosure-open;
}

.main > details > summary h2 {
    margin: 0;
}

.main > details > .details-content {
    max-height: none;
    opacity: 1;
}

.main summary a {
    font-size: 0.85em;
}

.toggle-all {
    font-size: 0.7rem;
    font-weight: normal;
    color: var(--fg-dim);
    cursor: pointer;
    margin-left: 0.75em;
    vertical-align: middle;
}

.toggle-all:hover {
    color: var(--link);
}

.main details .details-content {
    overflow: hidden;
    transition: max-height 0.3s ease, opacity 0.3s ease;
    max-height: 0;
    opacity: 0;
}

.main details[open] .details-content {
    opacity: 1;
}

.main details .details-content p {
    margin: 0.4rem 0 0.75rem 1.25rem;
}

.main details .details-content > ul,
.main details .details-content > ol {
    margin: 0.4rem 0 0.75rem 1.25rem;
}

.main details .details-content li {
    padding-left: 1em;
    text-indent: -1em;
}

/* Fallback for details without JS wrapper */
.main details > p {
    margin: 0.4rem 0 0.75rem 1.25rem;
}

/* Archived notice */
.archived-notice {
    color: var(--fg-dim);
    font-size: 0.85rem;
    margin-top: -1rem;
    margin-bottom: 1.5rem;
}

/* Highlighted text */
.highlight {
    color: var(--heading);
}

/* Sofa hero images */
.sofa-hero {
    display: flex;
    gap: 1.5rem;
    margin: 1.5rem 0;
    align-items: flex-end;
}

.sofa-hero img {
    height: 200px;
    width: auto;
    border: 1px solid var(--border);
    border-radius: 6px;
}

/* Sofa article figures */
.sofa-figures {
    display: flex;
    gap: 1rem;
    margin: 1rem 0 1rem 4rem;
    align-items: center;
}

.sofa-figures img {
    height: 160px;
    width: auto;
    max-width: calc(50% - 0.5rem);
    object-fit: contain;
}

/* References list (no bullets) */
ul.references li::before {
    content: none;
}

ul.references {
    list-style: none;
}

ul.references li {
    margin-bottom: 0.5rem;
}

/* Language tags */
.lang-tag {
    display: inline-block;
    font-size: 0.65rem;
    padding: 0.1em 0.5em;
    border-radius: 9px;
    margin-left: 0.3em;
    vertical-align: middle;
    font-weight: bold;
    letter-spacing: 0.02em;
    color: #fff;
}

.lang-tag.python       { background: #4a6a5a; }
.lang-tag.typescript   { background: #4a6a8a; }
.lang-tag.javascript   { background: #8a7a3a; }
.lang-tag.objc         { background: #5a7099; }
.lang-tag.c            { background: #6a6a6a; }
.lang-tag.cpp          { background: #4a6a85; }
.lang-tag.mathematica  { background: #994444; }
.lang-tag.maple        { background: #4a7a4a; }
.lang-tag.c30          { background: #7a6a50; }
.lang-tag.pic          { background: #6a7a6a; }
.lang-tag.ai           { background: #7a6a99; }

/* Book covers */
.book-covers {
    display: flex;
    gap: 1.5rem;
    margin-top: 1.5rem;
    flex-wrap: wrap;
}

.book-covers img {
    border: 1px solid var(--border);
    border-radius: 6px;
}

/* Blinking cursor for stub pages */
.cursor {
    display: inline-block;
    width: 0.6em;
    height: 1.1em;
    background: var(--fg);
    vertical-align: text-bottom;
    animation: blink 1s step-end infinite;
}

@keyframes blink {
    50% { opacity: 0; }
}

/* Mobile hamburger */
.menu-toggle {
    display: none;
    background: none;
    border: 1px solid var(--fg-dim);
    color: var(--fg);
    font-family: var(--font-mono);
    font-size: 1.2rem;
    padding: 0.25rem 0.75rem;
    cursor: pointer;
    position: fixed;
    top: 1rem;
    left: 1rem;
    z-index: 1000;
}

/* Responsive */
@media (max-width: 700px) {
    .menu-toggle {
        display: block;
    }

    .sidebar {
        transform: translateX(-100%);
        transition: transform 0.25s ease;
        z-index: 999;
        background: var(--bg);
    }

    .sidebar.open {
        transform: translateX(0);
    }

    .main {
        margin-left: 0;
        padding: 3.5rem 1.25rem 2rem;
    }
}