/* ==========================================================================
   Manyetik Kuvvet Simülasyonu — main.css
   Character: a lab notebook. Graph-paper canvas, blueprint-blue ink, a red
   pen for the force, monospace readouts and instrument-style controls.
   ========================================================================== */

/* ---------------------------------- Tokens ------------------------------- */
:root {
  /* Color */
  --canvas:      #f3f5f1;
  --surface:     #ffffff;
  --ink:         #16202c;
  --ink-mute:    #5a6573;
  --accent:      #1f5fbf;   /* blueprint ink — B field, controls */
  --accent-ink:  #ffffff;
  --accent-soft: #e6eefb;
  --force:       #d6342c;   /* red pen — the force */
  --current:     #e38a13;   /* amber — current and charges */
  --wire:        #2b3440;
  --grid:        #dfe6dc;
  --grid-major:  #c9d3c6;
  --hairline:    #d6dcd4;
  --focus:       #1f5fbf;

  /* Type */
  --font-display: "Space Grotesk", "Helvetica Neue", Arial, sans-serif;
  --font-body:    "Space Grotesk", "Helvetica Neue", Arial, sans-serif;
  --font-mono:    "JetBrains Mono", ui-monospace, "SF Mono", Menlo, monospace;
  --size-body:    16px;

  /* Space */
  --space-xs:   8px;
  --space-sm:   12px;
  --space-md:   16px;
  --space-lg:   24px;
  --space-xl:   32px;
  --space-xxl:  48px;
  --space-huge: 72px;

  /* Shape */
  --radius-sm:   6px;
  --radius-md:   10px;
  --radius-pill: 999px;

  /* Layout */
  --column: 1240px;
  --ease: cubic-bezier(0.22, 0.61, 0.36, 1);
}

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

html {
  -webkit-text-size-adjust: 100%;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  background: var(--canvas);
  color: var(--ink);
  font-family: var(--font-body);
  font-size: var(--size-body);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, p, dl, dd, ol, ul, figure, blockquote { margin: 0; }
ol, ul { padding: 0; list-style: none; }
img, svg, canvas { display: block; max-width: 100%; }
a { color: inherit; }
button, input, select, textarea { font: inherit; color: inherit; }

:focus-visible {
  outline: 2px solid var(--focus);
  outline-offset: 3px;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

/* ------------------------------- Typography ------------------------------ */
.display {
  font-family: var(--font-display);
  font-weight: 700;
  letter-spacing: -0.02em;
}
.display--lg { font-size: clamp(28px, 3.4vw, 40px); line-height: 1.1; }
.display--sm { font-size: 17px; line-height: 1.3; letter-spacing: -0.005em; }

.eyebrow {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--accent);
}

.lead { max-width: 64ch; color: var(--ink-mute); }

.mono { font-family: var(--font-mono); font-variant-numeric: tabular-nums; }

.formula {
  display: inline-block;
  padding: 6px 12px;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-sm);
  background: var(--surface);
  font-family: var(--font-mono);
  font-size: 15px;
}
.formula b { color: var(--force); font-weight: 600; }

.link { color: var(--accent); text-underline-offset: 3px; }

/* --------------------------------- Button -------------------------------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-xs);
  padding: 11px 18px;
  border: 1px solid var(--accent);
  border-radius: var(--radius-sm);
  background: var(--accent);
  color: var(--accent-ink);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  cursor: pointer;
  transition: background-color 0.2s var(--ease), border-color 0.2s var(--ease);
}
.btn:hover { background: #174a95; border-color: #174a95; }
.btn:disabled { opacity: 0.45; cursor: not-allowed; }

.btn--ghost { background: var(--surface); color: var(--ink); border-color: var(--hairline); }
.btn--ghost:hover { background: var(--accent-soft); border-color: var(--accent); color: var(--accent); }

.btn--block { width: 100%; }
.btn--sm { padding: 7px 12px; font-size: 13px; }

/* ---------------------------------- Nav ---------------------------------- */
.nav {
  border-bottom: 1px solid var(--hairline);
  background: var(--surface);
}
.nav__inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-md);
  max-width: var(--column);
  margin: 0 auto;
  padding: var(--space-sm) var(--space-lg);
}
.nav__brand {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  text-decoration: none;
}
.nav__link { font-size: 14px; color: var(--ink-mute); text-decoration: none; }
.nav__link:hover { color: var(--ink); }

/* --------------------------------- Bands --------------------------------- */
.band { padding: var(--space-xl) var(--space-lg); }
.band__inner {
  max-width: var(--column);
  margin: 0 auto;
}
.band__inner > * + * { margin-top: var(--space-lg); }

.head {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-end;
  justify-content: space-between;
  gap: var(--space-md);
}
.head > div > * + * { margin-top: var(--space-xs); }

/* ---------------------------------- Lab ---------------------------------- */
.lab {
  display: grid;
  grid-template-columns: minmax(0, 1fr) 320px;
  gap: var(--space-lg);
  align-items: start;
}

.stage {
  overflow: hidden;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background-color: var(--surface);
  background-image:
    linear-gradient(var(--grid-major) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid-major) 1px, transparent 1px),
    linear-gradient(var(--grid) 1px, transparent 1px),
    linear-gradient(90deg, var(--grid) 1px, transparent 1px);
  background-size: 100px 100px, 100px 100px, 20px 20px, 20px 20px;
}
.stage canvas {
  width: 100%;
  aspect-ratio: 2 / 1;
  touch-action: none;
  cursor: default;
}
.stage canvas.is-over { cursor: grab; }
.stage canvas.is-dragging { cursor: grabbing; }

.stage__foot {
  display: flex;
  flex-wrap: wrap;
  justify-content: space-between;
  gap: var(--space-xs) var(--space-md);
  padding: var(--space-sm) var(--space-md);
  border-top: 1px solid var(--hairline);
  background: var(--surface);
  font-size: 13px;
  color: var(--ink-mute);
}
.legend { display: flex; flex-wrap: wrap; gap: var(--space-md); }
.legend__item { display: inline-flex; align-items: center; gap: 6px; }
.legend__swatch { width: 14px; height: 3px; border-radius: 2px; }
.legend__swatch--field   { background: var(--accent); }
.legend__swatch--current { background: var(--current); }
.legend__swatch--force   { background: var(--force); }

/* Control panel */
.panel {
  padding: var(--space-lg);
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: var(--surface);
}
.panel > * + * { margin-top: var(--space-lg); }

.readout {
  padding: var(--space-md);
  border-radius: var(--radius-sm);
  background: var(--ink);
  color: #f3f5f1;
}
.readout__label {
  font-family: var(--font-mono);
  font-size: 12px;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  opacity: 0.7;
}
.readout__value {
  font-family: var(--font-mono);
  font-size: 34px;
  font-weight: 600;
  line-height: 1.2;
  color: #ff7a6e;
  font-variant-numeric: tabular-nums;
}
.readout__note { font-family: var(--font-mono); font-size: 12px; opacity: 0.7; }

.control > * + * { margin-top: 6px; }
.control__row {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: var(--space-sm);
}
.control__label { font-size: 14px; font-weight: 600; }
.control__value {
  font-family: var(--font-mono);
  font-size: 14px;
  color: var(--accent);
  font-variant-numeric: tabular-nums;
}

.range {
  width: 100%;
  height: 28px;
  margin: 0;
  background: transparent;
  accent-color: var(--accent);
  cursor: pointer;
}

.hint { font-size: 13px; color: var(--ink-mute); }

/* -------------------------------- Data table ----------------------------- */
.data-head {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-sm);
}
.exports { display: flex; flex-wrap: wrap; gap: var(--space-xs); }

.table-wrap {
  overflow: auto;
  border: 1px solid var(--hairline);
  border-radius: var(--radius-md);
  background: var(--surface);
}
.table {
  width: 100%;
  border-collapse: collapse;
  font-family: var(--font-mono);
  font-size: 14px;
  font-variant-numeric: tabular-nums;
}
.table th,
.table td {
  padding: 9px 14px;
  border-bottom: 1px solid var(--hairline);
  text-align: right;
  white-space: nowrap;
}
.table th {
  background: var(--canvas);
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 600;
  color: var(--ink-mute);
}
.table th:first-child, .table td:first-child { text-align: left; color: var(--ink-mute); }
.table td:last-child { color: var(--force); font-weight: 600; }
.table__empty td { text-align: center !important; color: var(--ink-mute) !important; font-family: var(--font-body); }

/* -------------------------------- Footer --------------------------------- */
.footer__inner {
  max-width: var(--column);
  margin: 0 auto;
  padding: var(--space-lg);
  font-size: 13px;
  color: var(--ink-mute);
}

/* ------------------------------ Responsive ------------------------------- */
@media (max-width: 980px) {
  .lab { grid-template-columns: 1fr; }
}

@media (max-width: 600px) {
  .band { padding-left: var(--space-md); padding-right: var(--space-md); }
  .readout__value { font-size: 28px; }
}

@media (prefers-reduced-motion: reduce) {
  html { scroll-behavior: auto; }
  *, *::before, *::after { transition-duration: 0.01ms !important; animation-duration: 0.01ms !important; }
}