:root {
    /* === NIGHT TRON THEME (Default) === */
    --bg: #000105;
    --text-primary: #d1f7ff;
    --text-title: #ffffff;
    --text-sub: #ff0055;
    --text-p: #d1f7ff;
    --neon-cyan: #00f0ff;
    --neon-pink: #ff0055;
    --neon-green: #39ff14;
    --grid-line: rgba(0, 240, 255, 0.22);
    --code-bg: #030a16;
    --code-header: rgba(0, 240, 255, 0.12);
    --code-border: rgba(0, 240, 255, 0.45);
    --code-text: #39ff14;
    --quote-bg: rgba(57, 255, 20, 0.12);
    --quote-text: #afff94;
    --quote-border: #39ff14;
    --modal-bg: #020b18;
    --modal-border: #00f0ff;
    --spotlight-bg: rgba(2, 11, 24, 0.94);
    --dock-bg: rgba(2, 10, 25, 0.85);
    --meta-color: #9fe8ff;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

html, body {
    background-color: var(--bg) !important;
    color: var(--text-primary) !important;
    font-family: 'Share Tech Mono', monospace;
    overflow: hidden;
    height: 100vh;
    height: 100dvh;
    width: 100vw;
    transition: background-color 0.2s ease, color 0.2s ease;
}

/* === DAY MODE (Crisp High-Contrast Precision Theme) === */
html.day-mode, body.day-mode {
    --bg: #f8fafc !important;
    --text-primary: #0f172a !important;
    --text-title: #0f172a !important;
    --text-sub: #be123c !important;
    --text-p: #1e293b !important;
    --neon-cyan: #0284c7 !important;
    --neon-pink: #e11d48 !important;
    --neon-green: #059669 !important;
    --grid-line: rgba(2, 132, 199, 0.1) !important;
    --code-bg: #0f172a !important;
    --code-header: #1e293b !important;
    --code-border: #334155 !important;
    --code-text: #38bdf8 !important;
    --quote-bg: #f1f5f9 !important;
    --quote-text: #0f172a !important;
    --quote-border: #0284c7 !important;
    --modal-bg: #ffffff !important;
    --modal-border: #0284c7 !important;
    --spotlight-bg: rgba(255, 255, 255, 0.98) !important;
    --dock-bg: #ffffff !important;
    --meta-color: #64748b !important;
}

/* Kill all dynamic void graphics in Day Mode */
body.day-mode .void-universe,
body.day-mode .singularity,
body.day-mode .accretion-ring,
body.day-mode .tunnel-grid-floor,
body.day-mode .tunnel-grid-ceiling,
body.day-mode .scanlines {
    display: none !important;
}

/* Day Mode Typography Overrides */
body.day-mode .brand-mark {
    color: #0284c7 !important;
    text-shadow: none !important;
}

body.day-mode .neon-title {
    color: #0f172a !important;
    text-shadow: none !important;
}

body.day-mode .neon-sub {
    color: #be123c !important;
    text-shadow: none !important;
}

body.day-mode .article-tags {
    color: #0284c7 !important;
}

body.day-mode .tron-p,
body.day-mode .tron-list li {
    color: #1e293b !important;
}

body.day-mode .cyan-highlight {
    color: #0284c7 !important;
    text-shadow: none !important;
}

body.day-mode .unc-quote {
    background: #f1f5f9 !important;
    color: #0f172a !important;
    border-left: 3px solid #0284c7 !important;
    text-shadow: none !important;
}

body.day-mode .inline-code {
    background: #e2e8f0 !important;
    color: #0369a1 !important;
    border: 1px solid #cbd5e1 !important;
}

body.day-mode .hud-btn,
body.day-mode .dock-btn {
    background: #ffffff !important;
    border-color: #cbd5e1 !important;
    color: #0284c7 !important;
    box-shadow: 0 2px 10px rgba(0, 0, 0, 0.08) !important;
}

body.day-mode .hud-btn:hover,
body.day-mode .dock-btn:hover {
    box-shadow: 0 4px 14px rgba(2, 132, 199, 0.25) !important;
    border-color: #0284c7 !important;
}

/* === READABLE MODE (Distraction-Free) === */
body.readable-mode .void-universe,
body.readable-mode .singularity,
body.readable-mode .accretion-ring,
body.readable-mode .tunnel-grid-floor,
body.readable-mode .tunnel-grid-ceiling,
body.readable-mode .scanlines {
    display: none !important;
    animation: none !important;
    opacity: 0 !important;
}

body.readable-mode:not(.day-mode) {
    --bg: #02060d !important;
    --text-primary: #f0faff !important;
    --text-p: #f0faff !important;
}

/* 3D Void Universe (Active in Night Mode) */
.void-universe {
    position: fixed;
    top: 0; left: 0;
    width: 100vw; height: 100vh;
    overflow: hidden;
    pointer-events: none;
    z-index: 1;
}

.singularity {
    position: absolute;
    top: 50%; left: 50%;
    width: 280px; height: 280px;
    margin: -140px 0 0 -140px;
    background: radial-gradient(circle, #000000 60%, rgba(0, 240, 255, 0.5) 80%, transparent 100%);
    border-radius: 50%;
    box-shadow: 0 0 80px 30px rgba(0, 240, 255, 0.4), 0 0 140px 60px rgba(255, 0, 85, 0.3);
    animation: rotate-singularity 6s infinite linear;
    z-index: 2;
}

.accretion-ring {
    position: absolute;
    top: 50%; left: 50%;
    width: 380px; height: 140px;
    margin: -70px 0 0 -190px;
    border: 2px solid rgba(0, 240, 255, 0.4);
    border-radius: 50%;
    box-shadow: 0 0 25px rgba(0, 240, 255, 0.6), inset 0 0 25px rgba(255, 0, 85, 0.4);
    transform: rotateX(70deg) rotateZ(25deg);
    animation: pulse-ring 3s infinite alternate ease-in-out;
    z-index: 2;
}

.tunnel-grid-floor {
    position: absolute;
    bottom: -50%; left: -50%;
    width: 200%; height: 120%;
    background-image: 
        linear-gradient(90deg, var(--grid-line) 1px, transparent 1px),
        linear-gradient(0deg, var(--grid-line) 1px, transparent 1px);
    background-size: 40px 40px;
    transform: perspective(300px) rotateX(75deg);
    transform-origin: center top;
    animation: fall-down 1.6s linear infinite;
    mask-image: radial-gradient(ellipse at 50% 0%, black 20%, transparent 80%);
    -webkit-mask-image: radial-gradient(ellipse at 50% 0%, black 20%, transparent 80%);
}

.tunnel-grid-ceiling {
    position: absolute;
    top: -50%; left: -50%;
    width: 200%; height: 120%;
    background-image: 
        linear-gradient(90deg, rgba(255, 0, 85, 0.2) 1px, transparent 1px),
        linear-gradient(0deg, rgba(255, 0, 85, 0.2) 1px, transparent 1px);
    background-size: 40px 40px;
    transform: perspective(300px) rotateX(-75deg);
    transform-origin: center bottom;
    animation: fall-up 1.6s linear infinite;
    mask-image: radial-gradient(ellipse at 50% 100%, black 20%, transparent 80%);
    -webkit-mask-image: radial-gradient(ellipse at 50% 100%, black 20%, transparent 80%);
}

@keyframes fall-down { 0% { background-position: 0 0; } 100% { background-position: 0 -40px; } }
@keyframes fall-up { 0% { background-position: 0 0; } 100% { background-position: 0 40px; } }
@keyframes rotate-singularity {
    0% { transform: scale(0.95) rotate(0deg); }
    50% { transform: scale(1.08) rotate(180deg); }
    100% { transform: scale(0.95) rotate(360deg); }
}
@keyframes pulse-ring {
    0% { transform: rotateX(70deg) rotateZ(20deg) scale(0.95); opacity: 0.7; }
    100% { transform: rotateX(70deg) rotateZ(30deg) scale(1.08); opacity: 1; }
}

.scanlines {
    position: fixed;
    top: 0; left: 0; width: 100vw; height: 100vh;
    background: linear-gradient(rgba(18, 16, 16, 0) 50%, rgba(0, 0, 0, 0.35) 50%);
    background-size: 100% 3px;
    pointer-events: none;
    z-index: 99;
    transition: opacity 0.2s ease;
}