/* ==========================================================================
   EduCanvas — Design System
   Neo-brutalist system inspired by the EduBuilders toolbox (toolbox.css /
   tailwind.css). Flat paper surface, hard ink borders, chunky offset shadows,
   electric/grape/sun/coral accents, Plus Jakarta Sans.

   HOW TO USE
   - Link this file AFTER the Tailwind CDN in index.html:
       <link rel="stylesheet" href="design-system.css">
   - Use the .ds-* component classes for buttons, cards, panels, inputs, etc.
   - Or reference the tokens directly via the CSS variables below.
   The goal is to let the app keep its existing markup while swapping the
   generic indigo/slate look for the brutalist EduBuilders identity.
   ========================================================================== */

/* --------------------------------------------------------------------------
   1. DESIGN TOKENS
   -------------------------------------------------------------------------- */
:root {
  /* Brand palette (from toolbox.css) */
  --ds-ink: #111111;        /* text / borders / shadows */
  --ds-paper: #FDFBF6;      /* base surface */
  --ds-electric: #3B1CFF;   /* primary accent */
  --ds-grape: #7A2BF5;      /* secondary accent */
  --ds-sun: #FFD400;        /* highlight / selection */
  --ds-sky-pop: #2D6BFF;    /* info accent */
  --ds-coral: #FF4D3D;      /* danger / destructive */
  --ds-aligned: #1F9D55;    /* success */
  --ds-partial: #F5B301;    /* warning */

  /* Semantic surfaces */
  --ds-surface: var(--ds-paper);
  --ds-surface-raised: #FFFFFF;
  --ds-surface-sunken: #F4F0E6;

  /* Ink alphas (match tailwind.css ink/NN utilities) */
  --ds-ink-10: hsla(0, 0%, 7%, 0.10);
  --ds-ink-15: hsla(0, 0%, 7%, 0.15);
  --ds-ink-20: hsla(0, 0%, 7%, 0.20);
  --ds-ink-40: hsla(0, 0%, 7%, 0.40);
  --ds-ink-60: hsla(0, 0%, 7%, 0.60);
  --ds-ink-70: hsla(0, 0%, 7%, 0.70);

  /* Typography */
  --ds-font-sans: "Plus Jakarta Sans", Inter, system-ui, sans-serif;
  --ds-font-mono: "JetBrains Mono", ui-monospace, monospace;

  /* Radii — brutalist = tight, deliberate curves, never pill-soft on structure */
  --ds-radius-sm: 6px;
  --ds-radius: 10px;
  --ds-radius-lg: 16px;

  /* Borders */
  --ds-border: 2px solid var(--ds-ink);
  --ds-border-thin: 1px solid var(--ds-ink-20);

  /* Brutalist offset shadows (from tailwind.css shadow-brutal*) */
  --ds-shadow-sm: 4px 4px 0 0 var(--ds-ink);
  --ds-shadow: 6px 6px 0 0 var(--ds-ink);
  --ds-shadow-lg: 10px 10px 0 0 var(--ds-ink);

  /* Motion */
  --ds-ease: cubic-bezier(0.4, 0, 0.2, 1);
  --ds-dur: 0.15s;
}

/* --------------------------------------------------------------------------
   2. BASE
   -------------------------------------------------------------------------- */
.ds-root,
body.ds-root {
  background-color: var(--ds-surface);
  color: var(--ds-ink);
  font-family: var(--ds-font-sans);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

.ds-root ::selection { background: var(--ds-sun); color: var(--ds-ink); }

/* Accessible focus ring on brutalist controls */
.ds-root :where(a, button, input, select, textarea, [tabindex]):focus-visible,
.ds-focus:focus-visible {
  outline: 3px solid var(--ds-electric);
  outline-offset: 2px;
}

/* --------------------------------------------------------------------------
   3. SURFACES — cards & panels
   -------------------------------------------------------------------------- */
.ds-card {
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius-lg);
  box-shadow: var(--ds-shadow);
  transition: transform var(--ds-dur) var(--ds-ease),
              box-shadow var(--ds-dur) var(--ds-ease);
}
.ds-card--interactive:hover {
  transform: translate(-2px, -2px);
  box-shadow: var(--ds-shadow-lg);
}
.ds-card--interactive:active {
  transform: translate(2px, 2px);
  box-shadow: var(--ds-shadow-sm);
}
.ds-card.is-selected {
  outline: 3px solid var(--ds-electric);
  outline-offset: 2px;
}

.ds-panel {
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius);
}
.ds-panel-header {
  border-bottom: var(--ds-border);
  background: var(--ds-surface-sunken);
}

/* Flat panel for sidebars / toolbars — single ink edge, no shadow */
.ds-rail {
  background: var(--ds-surface-raised);
  border-right: var(--ds-border);
}
.ds-rail--left { border-right: var(--ds-border); border-left: 0; }
.ds-rail--right { border-left: var(--ds-border); border-right: 0; }

/* Floating toolbar pill */
.ds-toolbar {
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius);
  box-shadow: var(--ds-shadow-sm);
}

/* --------------------------------------------------------------------------
   4. BUTTONS
   -------------------------------------------------------------------------- */
.ds-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  font-family: var(--ds-font-sans);
  font-weight: 700;
  font-size: 0.8125rem;
  line-height: 1;
  padding: 0.5rem 0.9rem;
  border: var(--ds-border);
  border-radius: var(--ds-radius-sm);
  background: var(--ds-surface-raised);
  color: var(--ds-ink);
  box-shadow: var(--ds-shadow-sm);
  cursor: pointer;
  transition: transform var(--ds-dur) var(--ds-ease),
              box-shadow var(--ds-dur) var(--ds-ease),
              background-color var(--ds-dur) var(--ds-ease);
}
.ds-btn:hover { transform: translate(-2px, -2px); box-shadow: var(--ds-shadow); }
.ds-btn:active { transform: translate(2px, 2px); box-shadow: 0 0 0 0 var(--ds-ink); }
.ds-btn:disabled { opacity: 0.5; cursor: default; transform: none; box-shadow: var(--ds-shadow-sm); }

.ds-btn--primary { background: var(--ds-electric); color: var(--ds-paper); }
.ds-btn--primary:hover { background: var(--ds-grape); }

.ds-btn--accent { background: var(--ds-sun); color: var(--ds-ink); }
.ds-btn--danger { background: var(--ds-coral); color: var(--ds-paper); }

/* Ghost / icon button — no shadow, fills with sun on hover */
.ds-btn--ghost {
  border: 2px solid transparent;
  box-shadow: none;
  background: transparent;
}
.ds-btn--ghost:hover {
  transform: none;
  border-color: var(--ds-ink);
  background: var(--ds-sun);
  box-shadow: none;
}
.ds-icon-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 0.4rem;
  border: 2px solid transparent;
  border-radius: var(--ds-radius-sm);
  background: transparent;
  color: var(--ds-ink);
  cursor: pointer;
  transition: background-color var(--ds-dur) var(--ds-ease),
              border-color var(--ds-dur) var(--ds-ease);
}
.ds-icon-btn:hover { background: var(--ds-sun); border-color: var(--ds-ink); }

/* Segmented control (view-mode switch) */
.ds-segment {
  display: inline-flex;
  gap: 2px;
  padding: 3px;
  border: var(--ds-border);
  border-radius: var(--ds-radius-sm);
  background: var(--ds-surface-sunken);
}
.ds-segment > button {
  border: 0;
  background: transparent;
  color: var(--ds-ink-60);
  font-weight: 700;
  font-size: 0.6875rem;
  padding: 0.35rem 0.6rem;
  border-radius: 4px;
  cursor: pointer;
}
.ds-segment > button[aria-pressed="true"] {
  background: var(--ds-ink);
  color: var(--ds-paper);
}

/* --------------------------------------------------------------------------
   5. FORM CONTROLS
   -------------------------------------------------------------------------- */
.ds-input,
.ds-select,
.ds-textarea {
  width: 100%;
  font-family: var(--ds-font-sans);
  font-size: 0.8125rem;
  color: var(--ds-ink);
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius-sm);
  padding: 0.55rem 0.7rem;
  transition: box-shadow var(--ds-dur) var(--ds-ease),
              border-color var(--ds-dur) var(--ds-ease);
}
.ds-input::placeholder,
.ds-textarea::placeholder { color: var(--ds-ink-40); }
.ds-input:focus,
.ds-select:focus,
.ds-textarea:focus {
  outline: none;
  box-shadow: var(--ds-shadow-sm);
}
.ds-textarea { resize: vertical; }

.ds-label {
  display: block;
  font-size: 0.625rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.06em;
  color: var(--ds-ink-60);
  margin-bottom: 0.3rem;
}

.ds-field-saved {
  border-color: var(--ds-aligned) !important;
  box-shadow: 0 0 0 3px rgba(31, 157, 85, 0.2) !important;
}

/* --------------------------------------------------------------------------
   6. BADGES, CHIPS & TAGS
   -------------------------------------------------------------------------- */
.ds-badge {
  display: inline-flex;
  align-items: center;
  gap: 0.25rem;
  font-size: 0.625rem;
  font-weight: 800;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  padding: 0.15rem 0.45rem;
  border: 2px solid var(--ds-ink);
  border-radius: 999px;
  background: var(--ds-sun);
  color: var(--ds-ink);
}
.ds-badge--electric { background: var(--ds-electric); color: var(--ds-paper); }
.ds-badge--count { min-width: 1.4rem; justify-content: center; }

.ds-chip {
  display: inline-flex;
  align-items: center;
  gap: 0.35rem;
  font-size: 0.6875rem;
  font-weight: 700;
  padding: 0.25rem 0.6rem;
  border: 2px solid var(--ds-ink);
  border-radius: 999px;
  background: var(--ds-surface-raised);
  color: var(--ds-ink);
  cursor: pointer;
  transition: background-color var(--ds-dur) var(--ds-ease);
}
.ds-chip[aria-pressed="true"],
.ds-chip.is-active { background: var(--ds-sun); }

/* --------------------------------------------------------------------------
   7. CANVAS SPECIFICS
   -------------------------------------------------------------------------- */
/* Dotted-grid canvas background, ink-tinted */
.ds-canvas-grid {
  background-color: var(--ds-surface);
  background-size: 24px 24px;
  background-image: radial-gradient(circle, var(--ds-ink-15) 1.4px, transparent 1.4px);
}

/* Node card on the canvas */
.ds-node {
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius);
  box-shadow: var(--ds-shadow-sm);
  transition: transform var(--ds-dur) var(--ds-ease),
              box-shadow var(--ds-dur) var(--ds-ease),
              opacity var(--ds-dur) var(--ds-ease);
  user-select: none;
}
.ds-node:hover { transform: translate(-2px, -2px); box-shadow: var(--ds-shadow); }
.ds-node.selected { outline: 3px solid var(--ds-electric); outline-offset: 2px; }
.ds-node.dimmed { opacity: 0.2; filter: grayscale(85%); }

/* Connectors */
.ds-connector {
  fill: none !important;
  stroke: var(--ds-ink);
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  transition: stroke var(--ds-dur) var(--ds-ease), stroke-width var(--ds-dur) var(--ds-ease);
}
.ds-connector--sequence { stroke-width: 4px; }
.ds-connector-group:hover .ds-connector {
  stroke: var(--ds-electric) !important;
  stroke-width: 3 !important;
}

/* --------------------------------------------------------------------------
   8. OVERLAYS — modals, drawers, toasts, tooltips
   -------------------------------------------------------------------------- */
.ds-backdrop {
  background: var(--ds-ink-40);
  -webkit-backdrop-filter: blur(1px);
  backdrop-filter: blur(1px);
}

.ds-modal {
  background: var(--ds-surface-raised);
  border: var(--ds-border);
  border-radius: var(--ds-radius-lg);
  box-shadow: var(--ds-shadow-lg);
}
.ds-drawer {
  background: var(--ds-surface-raised);
  border-left: var(--ds-border);
}

.ds-toast {
  background: var(--ds-ink);
  color: var(--ds-paper);
  border: 2px solid var(--ds-ink);
  border-radius: var(--ds-radius-sm);
  box-shadow: var(--ds-shadow-sm);
  font-weight: 700;
  font-size: 0.75rem;
}

.ds-tooltip {
  background: var(--ds-ink);
  color: var(--ds-paper);
  border: 2px solid var(--ds-ink);
  border-radius: var(--ds-radius-sm);
  font-size: 0.6875rem;
  font-weight: 700;
  box-shadow: var(--ds-shadow-sm);
}

/* --------------------------------------------------------------------------
   9. UTILITIES & SCROLLBARS
   -------------------------------------------------------------------------- */
.ds-divider { border: 0; border-top: 2px solid var(--ds-ink-10); }
.ds-divider--ink { border-top: 2px solid var(--ds-ink); }

/* Visible brutalist scrollbar (overrides hidden global bars) */
.ds-scroll {
  scrollbar-width: thin;
  scrollbar-color: var(--ds-ink) var(--ds-surface);
}
.ds-scroll::-webkit-scrollbar { width: 12px; height: 12px; }
.ds-scroll::-webkit-scrollbar-track { background: var(--ds-surface); border-left: 2px solid var(--ds-ink); }
.ds-scroll::-webkit-scrollbar-thumb { background: var(--ds-ink); border: 3px solid var(--ds-surface); }
.ds-scroll::-webkit-scrollbar-thumb:hover { background: var(--ds-electric); }

/* Accordion chevron (details/summary) */
.ds-root details > summary { list-style: none; }
.ds-root details > summary::-webkit-details-marker { display: none; }
.ds-chev { transition: transform var(--ds-dur) var(--ds-ease); }
.ds-root details[open] > summary .ds-chev { transform: rotate(180deg); }

/* --------------------------------------------------------------------------
   10. MOTION PREFERENCES
   -------------------------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  .ds-card, .ds-btn, .ds-node, .ds-icon-btn { transition: none !important; }
}