/* ══════════════════════════════════════════════════════════
   multivibrators.html  ·  page-specific styles
   ══════════════════════════════════════════════════════════ */

:root {
    --bg: #0a0a10;
    --bg-2: #12131c;
    --bg-panel: rgba(22, 23, 32, 0.75);
    --fg: #eef0f5;
    --text: #eef0f5;
    --text-dim: #d4d7e0;
    --muted: #8b90a3;
    --border: rgba(255, 255, 255, 0.09);
    --border-hover: rgba(255, 255, 255, 0.18);

    /* page semantic palette */
    --c-cap:      #58a6ff;   /* capacitor voltage trace */
    --c-output:   #ffcf5c;   /* comparator output trace */
    --c-trigger:  #7be089;   /* trigger pulse */
    --c-thresh:   #ff5c7a;   /* upper / lower thresholds */
    --c-thresh-h: #ff8aa6;
    --c-rail:     rgba(255, 255, 255, 0.30);
    --c-band:     rgba(255, 207, 92, 0.14);
    --c-resistor: #6a6f7c;
    --c-cap-fill: rgba(88, 166, 255, 0.22);

    --accent: var(--site-accent);
    --accent-soft: var(--site-accent-soft);
    --accent-soft-faint: var(--site-accent-soft-faint);
    --accent-soft-edge: var(--site-accent-soft-edge);

    --grid-line: rgba(255, 255, 255, 0.06);
    --grid-zero: rgba(255, 255, 255, 0.30);
    --tick-line: rgba(255, 255, 255, 0.25);
    --slider-track: rgba(255, 255, 255, 0.12);
    --pill-bg: rgba(255, 255, 255, 0.03);

    --body-size: 17px;
    --math-size: 18px;
    --hero-size: 60px;
}

[data-theme="light"] {
    --bg: #f5f5f7;
    --bg-2: #ffffff;
    --bg-panel: rgba(255, 255, 255, 0.92);
    --fg: #1a1a1e;
    --text: #1a1a1e;
    --text-dim: #2b2d38;
    --muted: #6a6f7c;
    --border: rgba(0, 0, 0, 0.10);
    --border-hover: rgba(0, 0, 0, 0.22);

    --c-cap:      #1d4ed8;
    --c-output:   #b88200;
    --c-trigger:  #2f8f3f;
    --c-thresh:   #dc2626;
    --c-thresh-h: #b8253a;
    --c-rail:     rgba(0, 0, 0, 0.30);
    --c-band:     rgba(184, 130, 0, 0.10);
    --c-resistor: #b8b8bd;
    --c-cap-fill: rgba(29, 78, 216, 0.16);

    --grid-line: rgba(0, 0, 0, 0.07);
    --grid-zero: rgba(0, 0, 0, 0.32);
    --tick-line: rgba(0, 0, 0, 0.22);
    --slider-track: rgba(0, 0, 0, 0.12);
    --pill-bg: rgba(0, 0, 0, 0.03);
}

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

html, body {
    background: var(--bg);
    color: var(--fg);
    font-family: 'Inter', system-ui, -apple-system, sans-serif;
    font-size: var(--body-size);
    line-height: 1.55;
    -webkit-font-smoothing: antialiased;
}
body { overflow-x: hidden; min-height: 100vh; }

.katex { font-size: var(--math-size) !important; }
.katex-display { margin: 0.6em 0 !important; }
.katex-display > .katex { font-size: calc(var(--math-size) * 1.06) !important; }
h1 .katex, h2 .katex, h3 .katex { font-size: inherit !important; }

a { color: var(--accent); }

/* ─── Brand and back ─── */
.brand {
    position: fixed; top: 20px; left: 24px; z-index: 40;
    font-size: 12px; color: var(--muted);
    letter-spacing: 0.08em; text-transform: uppercase;
    font-family: 'JetBrains Mono', monospace;
    display: flex; align-items: center; gap: 10px;
}
.brand .mark {
    width: 10px; height: 10px; border-radius: 50%;
    background: conic-gradient(var(--c-cap), var(--c-output), var(--c-thresh), var(--c-trigger), var(--c-cap));
}

.back-btn {
    position: fixed; top: 14px; right: 56px; z-index: 9999;
    display: inline-flex; align-items: center; gap: 8px;
    padding: 7px 14px; border-radius: 999px;
    background: var(--bg-panel); border: 1px solid var(--border);
    color: var(--fg); text-decoration: none;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px; letter-spacing: 0.06em; text-transform: uppercase;
    backdrop-filter: blur(8px); transition: all 0.15s;
}
.back-btn:hover { border-color: var(--accent); color: var(--accent); }

/* ─── Landing hero ─── */
.landing {
    min-height: 100vh; display: grid; place-items: center;
    padding: 120px 56px 80px; text-align: center; position: relative;
}
.landing .meta {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px; color: var(--muted);
    letter-spacing: 0.2em; text-transform: uppercase;
    margin-bottom: 28px;
}
h1.hero {
    font-size: var(--hero-size); line-height: 1.02;
    font-weight: 600; letter-spacing: -0.025em;
    margin: 0 auto 24px; max-width: 22ch;
}
h1.hero em {
    font-style: normal;
    background: linear-gradient(135deg, var(--c-cap), var(--c-output));
    -webkit-background-clip: text; background-clip: text; color: transparent;
}
.landing .sub {
    color: var(--muted); font-size: 18px;
    max-width: 64ch; margin: 12px auto 0; line-height: 1.6;
}
.landing .tags {
    margin-top: 36px; display: flex; gap: 12px;
    justify-content: center; flex-wrap: wrap;
}
.field-tag {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px; color: var(--muted);
    letter-spacing: 0.12em; text-transform: uppercase;
    display: inline-block; padding: 4px 10px;
    border: 1px solid var(--border); border-radius: 4px;
}
.scroll-hint {
    position: absolute; bottom: 32px; left: 50%; transform: translateX(-50%);
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px; letter-spacing: 0.2em;
    color: var(--muted); text-transform: uppercase;
    display: flex; flex-direction: column; align-items: center; gap: 8px;
}
.scroll-hint .line {
    width: 1px; height: 32px;
    background: linear-gradient(var(--muted), transparent);
    animation: pulse 2s infinite;
}
@keyframes pulse {
    0%, 100% { opacity: 0.3; } 50% { opacity: 1; }
}

/* ─── Scene layout ─── */
section.scene {
    min-height: 100vh; padding: 100px 40px 80px;
    display: grid;
    grid-template-columns: minmax(0, 1fr) minmax(0, 1.5fr);
    gap: 32px; align-items: start;
    border-bottom: 1px solid var(--border);
}
section.scene.wide {
    grid-template-columns: 1fr;
}
section.scene .copy { max-width: 640px; }
section.scene .copy.full { max-width: 1100px; margin: 0 auto; }

.eyebrow {
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px; letter-spacing: 0.18em; text-transform: uppercase;
    color: var(--muted); margin-bottom: 18px;
    display: flex; align-items: center; gap: 10px;
}
.eyebrow .num { color: var(--accent); }
.eyebrow .bar { flex: 0 0 28px; height: 1px; background: var(--accent); }

h2 {
    font-size: 34px; line-height: 1.12;
    font-weight: 600; letter-spacing: -0.02em;
    margin: 0 0 18px; color: var(--fg);
}
h2 em { font-style: normal; }

h3 {
    font-size: 17px; font-weight: 600;
    margin: 22px 0 8px; color: var(--fg); letter-spacing: -0.01em;
}

p { margin: 0 0 14px; color: var(--text-dim); }
p.lead { font-size: calc(var(--body-size) + 1px); color: var(--fg); }
p.dim  { color: var(--muted); }

ul.bullets {
    list-style: none; padding: 0;
    margin: 12px 0 14px;
}
ul.bullets li {
    color: var(--text-dim);
    padding: 6px 0 6px 18px;
    position: relative;
    font-size: 15px; line-height: 1.55;
}
ul.bullets li::before {
    content: ""; position: absolute;
    left: 2px; top: 14px;
    width: 6px; height: 6px; border-radius: 50%;
    background: var(--accent);
}

strong { color: var(--fg); font-weight: 600; }

.eq-block {
    display: block; margin: 16px 0;
    padding: 14px 18px;
    background: var(--accent-soft-faint);
    border: 1px solid var(--accent-soft-edge);
    border-radius: 10px; text-align: center; color: var(--fg);
    overflow-x: auto;
}

.callout {
    margin-top: 18px; padding: 14px 18px;
    border-left: 2px solid var(--accent);
    background: var(--accent-soft-faint);
    border-radius: 0 8px 8px 0;
    font-size: 14px; color: var(--text-dim); line-height: 1.7;
}
.callout em { font-style: italic; }

/* ─── Plot stack ─── */
.plot-stack {
    display: flex; flex-direction: column; gap: 14px;
    width: 100%;
}

.plot-box {
    position: relative;
    border: 1px solid var(--border);
    border-radius: 12px; background: var(--bg-2);
    overflow: hidden; width: 100%;
}
.plot-box.classification { aspect-ratio: 1.7 / 1; }
.plot-box.circuit        { aspect-ratio: 1.3 / 1; }
.plot-box.scope          { aspect-ratio: 1.7 / 1; }
.plot-box svg { display: block; width: 100%; height: 100%; }
.plot-box canvas { display: block; width: 100%; height: 100%; }
.plot-box.scope { position: relative; }
.scope-overlay {
    position: absolute; inset: 0;
    width: 100%; height: 100%;
    pointer-events: none;
    overflow: visible;
}
.scope-overlay foreignObject { overflow: visible; }
.plot-box.circuit svg,
.plot-box.classification svg { padding: 16px; }

.plot-box .label {
    position: absolute; top: 10px; left: 14px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px; letter-spacing: 0.12em; text-transform: uppercase;
    color: var(--muted); z-index: 2; pointer-events: none;
}
.plot-box .label b {
    font-weight: 600; letter-spacing: 0.06em; color: var(--fg);
}

/* ─── Controls and toolbar ─── */
.toolbar {
    display: flex; gap: 10px 14px; flex-wrap: wrap; align-items: center;
    padding: 10px 12px;
    background: var(--bg-panel);
    border: 1px solid var(--border); border-radius: 10px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px;
}
.toolbar .divider {
    width: 1px; height: 18px; background: var(--border); margin: 0 4px;
}
.toolbar .slider-group {
    display: inline-flex; align-items: center; gap: 10px;
    padding: 4px 8px;
}
.toolbar .slider-group .lab {
    color: var(--muted); font-size: 10px;
    letter-spacing: 0.1em; text-transform: uppercase;
}
.toolbar .slider-group .val {
    color: var(--fg); min-width: 6ch; text-align: right;
}
.toolbar input[type="range"] {
    -webkit-appearance: none; appearance: none;
    width: 130px; height: 4px;
    background: var(--slider-track); border-radius: 999px;
    outline: none;
}
.toolbar input[type="range"]::-webkit-slider-thumb {
    -webkit-appearance: none; appearance: none;
    width: 14px; height: 14px; border-radius: 50%;
    background: var(--accent); cursor: pointer;
    border: 2px solid var(--bg-2);
}
.toolbar input[type="range"]::-moz-range-thumb {
    width: 14px; height: 14px; border-radius: 50%;
    background: var(--accent); cursor: pointer;
    border: 2px solid var(--bg-2);
}
.ctrl-btn {
    font-family: 'JetBrains Mono', monospace;
    font-size: 10px; letter-spacing: 0.1em; text-transform: uppercase;
    color: var(--fg); background: var(--pill-bg);
    border: 1px solid var(--border); border-radius: 6px;
    padding: 6px 12px; cursor: pointer;
    transition: all 0.15s;
}
.ctrl-btn:hover {
    border-color: var(--accent); color: var(--accent);
}
.ctrl-btn.active {
    border-color: var(--accent); color: var(--accent);
    background: var(--accent-soft-faint);
}
.ctrl-btn.trigger {
    border-color: var(--c-trigger); color: var(--c-trigger);
}
.ctrl-btn.trigger:hover {
    background: rgba(123, 224, 137, 0.10);
}

/* ─── SVG plot styling ─── */
svg.bode text {
    font-family: 'JetBrains Mono', monospace;
    font-size: 12px; fill: var(--muted);
}
svg.bode .grid line { stroke: var(--grid-line); stroke-width: 1; }
svg.bode .axis-line { stroke: var(--grid-zero); stroke-width: 1.4; }
svg.bode .axis-tick text { fill: var(--muted); font-size: 12px; }
svg.bode .axis-tick line { stroke: var(--tick-line); stroke-width: 1; }
svg.bode foreignObject { overflow: visible; }

/* ─── Application cards ─── */
.card-row {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(280px, 1fr));
    gap: 16px; margin-top: 28px;
}
.card {
    padding: 18px 18px 16px;
    background: var(--bg-2);
    border: 1px solid var(--border);
    border-radius: 10px;
    position: relative;
}
.card:hover { border-color: var(--border-hover); }
.card-num {
    position: absolute; top: 14px; right: 16px;
    font-family: 'JetBrains Mono', monospace;
    font-size: 11px; color: var(--accent);
    letter-spacing: 0.1em; text-transform: uppercase;
}
.card h3 {
    margin: 0 0 8px; font-size: 15px; padding-right: 24px;
}
.card p {
    margin: 0; font-size: 14px; color: var(--text-dim); line-height: 1.55;
}

/* ─── Footer ─── */
footer {
    padding: 60px 56px 80px; text-align: center;
    color: var(--muted); font-size: 13px;
    border-top: 1px solid var(--border);
    font-family: 'JetBrains Mono', monospace;
    letter-spacing: 0.08em; text-transform: uppercase;
}

/* Circuit hover hit areas and tooltip rules live in
   components/circuit_tooltip.css (linked from the page). */

@media (max-width: 900px) {
    section.scene { grid-template-columns: 1fr; padding: 80px 24px 60px; }
    h1.hero { font-size: 42px; }
    h2 { font-size: 26px; }
    .brand { top: 16px; left: 16px; }
}