@import url('https://fonts.googleapis.com/css2?family=Inter:wght@400;500;600;700;800&family=JetBrains+Mono:wght@400;500;600&display=swap');

/* ───────────────────────────────────────────────
   Design Tokens
   ─────────────────────────────────────────────── */
:root {
    /* Backgrounds - Softer dark grey to prevent eye strain */
    --bg: #0b0d10;
    --surface: #111418;
    --surface-alt: #161a1f;
    --surface-hover: #1c2128;
    --border: #332300;
    --border-light: #4d3500;

    /* Text - Highly legible off-whites/greys for reading long paragraphs */
    --text-main: #e2e8f0;
    --text-secondary: #94a3b8;
    --text-muted: #64748b;
    --text-light: #475569;
    --ink: #ffb000;

    /* Accent palette - Engineering Amber */
    --accent: #ffb000;
    --accent-dark: #cc8d00;
    --accent-light: #332300;
    --accent-muted: rgba(255, 176, 0, 0.05);
    
    /* Override all other theme colors to force monochrome */
    --accent-cyan: #ffb000;
    --accent-purple: #ffb000;
    --accent-pink: #ffb000;
    --accent-orange: #ffb000;
    --accent-red: #ffb000;
    --accent-green: #ffb000;
    --accent-secondary: #ffb000;

    /* Radii & Shadows - Wireframe Sharp */
    --radius: 0px;
    --shadow-sm: none;
    --shadow-md: 0 0 12px rgba(255, 176, 0, 0.1);
    --shadow-lg: 0 0 24px rgba(255, 176, 0, 0.15);
}

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

/* ───────────────────────────────────────────────
   Body
   ─────────────────────────────────────────────── */
body {
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    background-color: var(--bg);
    background-image: 
        linear-gradient(rgba(255, 176, 0, 0.025) 1px, transparent 1px),
        linear-gradient(90deg, rgba(255, 176, 0, 0.025) 1px, transparent 1px);
    background-size: 32px 32px;
    background-position: center top;
    color: var(--text-main);
    line-height: 1.7;
    font-size: 16px;
    overflow-x: hidden;
    min-height: 100vh;
    display: flex;
    flex-direction: row;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* ───────────────────────────────────────────────
   Sidebar Navigation — Quantum White
   ─────────────────────────────────────────────── */
nav.sidebar {
    background: rgba(10, 10, 10, 0.85);
    backdrop-filter: blur(16px);
    -webkit-backdrop-filter: blur(16px);
    border-right: 1px solid var(--border);
    box-shadow: 4px 0 30px -4px rgba(255, 176, 0, 0.05);
    width: 220px;
    flex-shrink: 0;
    height: 100vh;
    position: sticky;
    top: 0;
    z-index: 100;
    display: flex;
    flex-direction: column;
    padding: 0;
    overflow-y: auto;
    scrollbar-width: thin;
    scrollbar-color: rgba(0,0,0,0.08) transparent;
    transition: transform 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
nav.sidebar::before {
    content: '';
    position: absolute;
    top: 0; left: 0; right: 0;
    height: 1px;
    background: linear-gradient(90deg,
        transparent 0%,
        rgba(255, 176, 0, 0.2) 20%,
        rgba(255, 176, 0, 0.5) 50%,
        rgba(255, 176, 0, 0.2) 80%,
        transparent 100%);
    z-index: 2;
}

/* Thin custom scrollbar (webkit) */
nav.sidebar::-webkit-scrollbar { width: 5px; }
nav.sidebar::-webkit-scrollbar-track { background: transparent; }
nav.sidebar::-webkit-scrollbar-thumb { background: rgba(0,0,0,0.06); border-radius: 3px; }
nav.sidebar::-webkit-scrollbar-thumb:hover { background: rgba(0,0,0,0.12); }

.sidebar-header {
    display: flex;
    align-items: center;
    gap: 0.65rem;
    padding: 1.5rem 1.25rem 1.15rem;
    position: relative;
}
.sidebar-header::after {
    content: '';
    position: absolute;
    bottom: 0; left: 1.25rem; right: 1.25rem;
    height: 1px;
    background: linear-gradient(90deg,
        rgba(79, 70, 229, 0.08),
        rgba(124, 58, 237, 0.04),
        transparent);
}
.quantum-orbital {
    flex-shrink: 0;
    opacity: 0.5;
    filter: drop-shadow(0 0 4px rgba(79, 70, 229, 0.08));
    animation: orbital-spin 25s linear infinite;
}
@keyframes orbital-spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}
@media (prefers-reduced-motion: reduce) {
    .quantum-orbital { animation: none; }
}

.nav-logo {
    font-family: 'JetBrains Mono', monospace;
    font-weight: 800;
    font-size: 0.95rem;
    text-decoration: none;
    letter-spacing: 0.06em;
    text-transform: uppercase;
    font-variant: small-caps;
    display: block;
    color: var(--ink);
}

.nav-links {
    display: flex;
    flex-direction: column;
    gap: 1px;
    padding: 0.5rem 0.75rem;
    flex: 1;
}

.nav-links a {
    color: var(--text-muted);
    font-family: 'JetBrains Mono', monospace;
    text-decoration: none;
    padding: 0.4rem 0.65rem;
    border-radius: var(--radius);
    font-weight: 500;
    font-size: 0.85rem;
    transition: color 0.2s, background 0.2s;
    letter-spacing: 0.005em;
    display: block;
    position: relative;
}

.nav-links a:hover {
    color: var(--accent);
    background: var(--accent-muted);
}

.nav-links a.active {
    color: var(--accent);
    background: var(--accent-muted);
    font-weight: 600;
}
.nav-links a.active::before {
    content: '';
    position: absolute;
    left: -0.15rem;
    top: 50%;
    transform: translateY(-50%);
    width: 3px; height: 14px;
    border-radius: 0px;
    background: var(--accent);
    box-shadow: 0 0 6px var(--accent);
}

/* Nav section separators */
.nav-sep {
    display: flex;
    align-items: center;
    gap: 0.45rem;
    font-size: 0.65rem;
    font-weight: 700;
    text-transform: uppercase;
    letter-spacing: 0.1em;
    color: var(--text-muted);
    padding: 1rem 0.65rem 0.25rem;
    margin-top: 0.25rem;
    user-select: none;
    font-family: 'JetBrains Mono', monospace;
}
.nav-sep::before {
    content: '';
    width: 3px; height: 3px;
    border-radius: 0px;
    background: var(--border-light);
    flex-shrink: 0;
}

.sidebar-footer {
    margin-top: auto;
    padding: 0.5rem 1.25rem 0.75rem;
    opacity: 0.45;
}
.sidebar-wave {
    width: 100%;
    height: 28px;
}

/* ───────────────────────────────────────────────
   Content Area & Container
   ─────────────────────────────────────────────── */
.content-area {
    flex: 1;
    display: flex;
    flex-direction: column;
    min-width: 0;
    min-height: 100vh;
    background: var(--bg);
}

.container {
    max-width: 860px;
    margin: 0 auto;
    padding: 3rem 3rem 4rem;
    flex: 1;
    width: 100%;
}

/* ───────────────────────────────────────────────
   Mobile Navigation & Responsive Layout
   ─────────────────────────────────────────────── */
.mobile-header {
    display: none;
    align-items: center;
    justify-content: space-between;
    padding: 1rem 1.5rem;
    background: rgba(10, 10, 10, 0.85);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border);
    position: sticky;
    top: 0;
    z-index: 90;
    width: 100%;
}
.mobile-logo {
    display: flex;
    align-items: center;
    gap: 0.5rem;
    font-family: 'JetBrains Mono', monospace;
    font-weight: 800;
    font-size: 0.95rem;
    letter-spacing: 0.05em;
    text-transform: uppercase;
    color: var(--ink);
}
.mobile-menu-btn {
    background: none;
    border: none;
    color: var(--text-main);
    cursor: pointer;
    padding: 0.25rem;
    display: flex;
    align-items: center;
    justify-content: center;
}
.sidebar-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(15, 17, 23, 0.4);
    backdrop-filter: blur(4px);
    -webkit-backdrop-filter: blur(4px);
    z-index: 95;
    opacity: 0;
    transition: opacity 0.3s ease;
}
.sidebar-overlay.active {
    display: block;
    opacity: 1;
}

@media (max-width: 900px) {
    body {
        flex-direction: column;
    }
    .mobile-header {
        display: flex;
    }
    nav.sidebar {
        position: fixed;
        left: 0;
        top: 0;
        transform: translateX(-100%);
        height: 100dvh;
        width: 280px;
        background: rgba(255, 255, 255, 0.95);
    }
    nav.sidebar.active {
        transform: translateX(0);
    }
    .container {
        padding: 2rem 1.5rem 3rem;
    }
}
   Typography
   ─────────────────────────────────────────────── */
h1 {
    font-family: 'JetBrains Mono', monospace;
    font-size: 2.4rem;
    margin-bottom: 1.25rem;
    line-height: 1.15;
    letter-spacing: -0.02em;
    font-weight: 800;
    color: var(--ink);
}

h2 {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.5rem;
    margin: 3rem 0 1rem;
    padding-bottom: 0.5rem;
    border-bottom: 1px solid var(--border-light);
    font-weight: 700;
    color: var(--accent);
    letter-spacing: -0.01em;
}

h3 {
    font-family: 'JetBrains Mono', monospace;
    font-size: 1.2rem;
    margin-bottom: 0.75rem;
    color: var(--text-main);
    font-weight: 700;
}

p {
    font-size: 1.05rem;
    color: var(--text-secondary);
    margin-bottom: 1.25rem;
    max-width: 70ch;
}

ul, ol {
    margin-left: 1.5rem;
    margin-bottom: 1.25rem;
    color: var(--text-secondary);
    font-size: 1.05rem;
    max-width: 70ch;
}

li {
    margin-bottom: 0.4rem;
}

strong {
    color: var(--text-main);
    font-weight: 700;
}

a {
    color: var(--accent);
    text-decoration: none;
    transition: color 0.15s ease;
}

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

.gradient-text {
    color: var(--accent);
    background: none;
    -webkit-background-clip: unset;
    background-clip: unset;
}

/* ───────────────────────────────────────────────
   Grid & Cards (hardware-module panel style)
   ─────────────────────────────────────────────── */
.grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(320px, 1fr));
    gap: 1.25rem;
    margin: 2rem 0;
}

.card {
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius);
    padding: 1.75rem 2rem;
    transition: box-shadow 0.25s ease, transform 0.2s ease;
    box-shadow: var(--shadow-sm);
    position: relative;
}

.card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

/* ───────────────────────────────────────────────
   Math & Code Blocks (light themed)
   ─────────────────────────────────────────────── */
.math-box {
    font-family: 'JetBrains Mono', monospace;
    background: var(--surface-alt);
    color: var(--text-main);
    padding: 1.25rem 1.5rem;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    margin: 1.5rem 0;
    overflow-x: auto;
    text-align: center;
    font-size: 0.95rem;
    line-height: 1.8;
}

code {
    font-family: 'JetBrains Mono', monospace;
    background: var(--accent-muted);
    padding: 0.15rem 0.4rem;
    border-radius: 3px;
    color: var(--accent-dark);
    font-size: 0.9em;
}

pre {
    background: var(--surface-alt);
    color: var(--text-main);
    padding: 1.25rem 1.5rem;
    border-radius: var(--radius);
    border: 1px solid var(--border);
    overflow-x: auto;
    margin: 1.5rem 0;
    font-family: 'JetBrains Mono', monospace;
    font-size: 0.9rem;
    line-height: 1.7;
}

/* Reset code inside pre */
pre code {
    background: none;
    padding: 0;
    border-radius: 0;
    color: inherit;
    font-size: inherit;
}

/* ───────────────────────────────────────────────
   SVG Containers
   ─────────────────────────────────────────────── */
.svg-container {
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: var(--radius);
    padding: 2rem;
    margin: 2rem 0;
    overflow: hidden;
    box-shadow: var(--shadow-sm);
}

/* ───────────────────────────────────────────────
   Tags
   ─────────────────────────────────────────────── */
.tag {
    display: inline-block;
    padding: 0.2rem 0.75rem;
    border: none;
    border-radius: var(--radius);
    font-size: 0.75rem;
    font-weight: 600;
    text-transform: uppercase;
    letter-spacing: 0.06em;
    margin-bottom: 1rem;
    color: var(--accent-dark);
    background: var(--accent-light);
    font-family: 'JetBrains Mono', monospace;
}

/* ───────────────────────────────────────────────
   Footer
   ─────────────────────────────────────────────── */
footer {
    text-align: center;
    padding: 2rem;
    border-top: 1px solid var(--border-light);
    color: var(--text-muted);
    font-size: 0.88rem;
    background: transparent;
}

/* ───────────────────────────────────────────────
   Glossary (dt/dd)
   ─────────────────────────────────────────────── */
dt {
    font-weight: 800;
    color: var(--accent);
    font-size: 1.15rem;
    margin-top: 1.5rem;
    font-family: 'Inter', sans-serif;
}

dd {
    color: var(--text-secondary);
    margin-bottom: 1rem;
    margin-left: 1rem;
}

/* ───────────────────────────────────────────────
   Source Cards (reference citations)
   ─────────────────────────────────────────────── */
.source-card {
    position: relative;
    padding: 1.25rem 1.5rem;
    background: var(--surface);
    border: 1px solid var(--border-light);
    border-radius: var(--radius);
    margin-bottom: 1rem;
    box-shadow: var(--shadow-sm);
    transition: box-shadow 0.2s ease, transform 0.2s ease;
}

/* Top accent line for source cards */
.source-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    right: 0;
    height: 2px;
    background: var(--accent-secondary);
    border-radius: var(--radius) var(--radius) 0 0;
    opacity: 0.5;
    transition: opacity 0.2s ease;
}

.source-card:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
}

.source-card:hover::before {
    opacity: 1;
}

.source-card a {
    color: var(--accent-secondary);
    text-decoration: none;
    font-weight: 700;
    font-size: 1.05rem;
}

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