/* ==========================================================================
   LurkBot Signal Scanner — Editorial/Industrial Design System
   ========================================================================== */

:root {
  /* === BRAND ORIGIN: Professional Blue-Slate === */
  --color-primary-origin: oklch(0.50 0.14 255);

  /* === PRIMARY SCALE (11 shades) === */
  --color-primary-50:  oklch(from var(--color-primary-origin) 0.97 calc(c * 0.15) h);
  --color-primary-100: oklch(from var(--color-primary-origin) 0.93 calc(c * 0.25) h);
  --color-primary-200: oklch(from var(--color-primary-origin) 0.87 calc(c * 0.45) h);
  --color-primary-300: oklch(from var(--color-primary-origin) 0.78 calc(c * 0.65) h);
  --color-primary-400: oklch(from var(--color-primary-origin) 0.68 calc(c * 0.85) h);
  --color-primary-500: oklch(from var(--color-primary-origin) 0.58 calc(c * 1.00) h);
  --color-primary-600: oklch(from var(--color-primary-origin) 0.48 calc(c * 0.95) h);
  --color-primary-700: oklch(from var(--color-primary-origin) 0.39 calc(c * 0.85) h);
  --color-primary-800: oklch(from var(--color-primary-origin) 0.31 calc(c * 0.70) h);
  --color-primary-900: oklch(from var(--color-primary-origin) 0.25 calc(c * 0.50) h);
  --color-primary-950: oklch(from var(--color-primary-origin) 0.18 calc(c * 0.40) h);

  /* === NEUTRAL SCALE — Tinted with Primary Hue === */
  --color-base-50:  oklch(from var(--color-primary-origin) 0.97 0.008 h);
  --color-base-100: oklch(from var(--color-primary-origin) 0.93 0.010 h);
  --color-base-200: oklch(from var(--color-primary-origin) 0.87 0.012 h);
  --color-base-300: oklch(from var(--color-primary-origin) 0.78 0.014 h);
  --color-base-400: oklch(from var(--color-primary-origin) 0.65 0.012 h);
  --color-base-500: oklch(from var(--color-primary-origin) 0.52 0.010 h);
  --color-base-600: oklch(from var(--color-primary-origin) 0.40 0.010 h);
  --color-base-700: oklch(from var(--color-primary-origin) 0.30 0.008 h);
  --color-base-800: oklch(from var(--color-primary-origin) 0.22 0.006 h);
  --color-base-900: oklch(from var(--color-primary-origin) 0.15 0.005 h);
  --color-base-950: oklch(from var(--color-primary-origin) 0.10 0.004 h);

  /* === SEMANTIC TOKENS === */
  --surface-page:      var(--color-base-50);
  --surface-card:      oklch(1 0 0);
  --surface-subtle:    var(--color-base-100);
  --surface-selected:  var(--color-base-200);

  --text-primary:      var(--color-base-900);
  --text-secondary:    var(--color-base-600);
  --text-muted:        var(--color-base-400);
  --text-inverse:      var(--color-base-50);

  --border-subtle:     var(--color-base-200);
  --border-default:    var(--color-base-300);
  --border-strong:     var(--color-base-400);

  /* === STATUS COLORS === */
  --status-high-bg:    oklch(0.95 0.06 145);
  --status-high-text:  oklch(0.35 0.12 145);
  --status-medium-bg:  oklch(0.95 0.05 85);
  --status-medium-text: oklch(0.40 0.10 85);
  --status-low-bg:     oklch(0.95 0.03 25);
  --status-low-text:   oklch(0.40 0.12 25);

  --signal-bg:         oklch(0.93 0.04 25);
  --signal-text:       oklch(0.35 0.12 25);
  --keyword-bg:        oklch(0.93 0.04 300);
  --keyword-text:      oklch(0.35 0.12 300);

  /* === TYPOGRAPHY === */
  --font-sans: -apple-system, BlinkMacSystemFont, "Inter", "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", ui-monospace, monospace;

  --text-xs:   clamp(0.75rem,  0.7rem  + 0.25vw, 0.875rem);
  --text-sm:   clamp(0.875rem, 0.825rem + 0.25vw, 1rem);
  --text-base: clamp(1rem,     0.95rem + 0.25vw,  1.125rem);
  --text-lg:   clamp(1.125rem, 1.05rem + 0.3vw,   1.25rem);
  --text-xl:   clamp(1.25rem,  1.15rem + 0.5vw,   1.5rem);
  --text-2xl:  clamp(1.5rem,   1.35rem + 0.75vw,  1.875rem);

  --weight-normal:   400;
  --weight-medium:   500;
  --weight-semibold: 600;
  --weight-bold:     700;

  --leading-tight:  1.25;
  --leading-snug:   1.4;
  --leading-normal: 1.6;

  --tracking-tight:  -0.02em;
  --tracking-normal:  0em;
  --tracking-wide:    0.04em;

  /* === SPACING (8px grid) === */
  --space-1:  0.25rem;  /*  4px */
  --space-2:  0.5rem;   /*  8px */
  --space-3:  0.75rem;  /* 12px */
  --space-4:  1rem;     /* 16px */
  --space-6:  1.5rem;   /* 24px */
  --space-8:  2rem;     /* 32px */
  --space-12: 3rem;     /* 48px */

  --radius-sm: 4px;
  --radius-md: 6px;
  --radius-lg: 8px;

  /* === TRANSITIONS === */
  --transition-fast: 150ms ease-out;
  --transition-base: 200ms ease-out;

  /* === SHADOWS === */
  --shadow-xs: 0 1px 2px oklch(0.20 0.01 255 / 0.08);
  --shadow-sm: 0 1px 3px oklch(0.20 0.01 255 / 0.10);
}

@media (prefers-color-scheme: dark) {
  :root {
    --surface-page:      var(--color-base-900);
    --surface-card:      var(--color-base-800);
    --surface-subtle:    var(--color-base-700);
    --surface-selected:  var(--color-base-600);

    --text-primary:      var(--color-base-50);
    --text-secondary:    var(--color-base-300);
    --text-muted:        var(--color-base-400);

    --border-subtle:     var(--color-base-700);
    --border-default:    var(--color-base-600);
  }
}

/* ==========================================================================
   BASE LAYOUT
   ========================================================================== */

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

body {
  font-family: var(--font-sans);
  font-size: var(--text-base);
  line-height: var(--leading-normal);
  color: var(--text-primary);
  background: var(--surface-page);
  margin: 0;
  padding: 0;
  font-variant-numeric: tabular-nums;
}

.container {
  max-width: 80rem;
  margin: 0 auto;
  padding: var(--space-6) clamp(var(--space-4), 4vw, var(--space-8));
}

/* ==========================================================================
   HEADER
   ========================================================================== */

header {
  border-bottom: 1px solid var(--border-subtle);
  margin-bottom: var(--space-8);
  padding-bottom: var(--space-6);
}

h1 {
  font-size: var(--text-2xl);
  font-weight: var(--weight-bold);
  letter-spacing: var(--tracking-tight);
  color: var(--text-primary);
  margin: 0;
  line-height: var(--leading-tight);
}

h1 small {
  font-size: var(--text-lg);
  font-weight: var(--weight-normal);
  color: var(--text-secondary);
  letter-spacing: var(--tracking-normal);
}

/* ==========================================================================
   CONTROLS
   ========================================================================== */

.controls {
  display: flex;
  gap: var(--space-3);
  align-items: center;
  flex-wrap: wrap;
  margin-bottom: var(--space-8);
  padding: var(--space-4);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
}

button {
  font-family: inherit;
  font-size: var(--text-sm);
  font-weight: var(--weight-medium);
  line-height: 1;
  padding: var(--space-3) var(--space-4);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-md);
  background: var(--surface-card);
  color: var(--text-primary);
  cursor: pointer;
  transition: all var(--transition-fast);
  min-height: 44px;
}

button:hover {
  background: var(--surface-subtle);
  border-color: var(--border-strong);
}

button:focus-visible {
  outline: 2px solid var(--color-primary-500);
  outline-offset: 2px;
}

button.primary {
  background: var(--color-primary-600);
  border-color: var(--color-primary-600);
  color: var(--text-inverse);
}

button.primary:hover {
  background: var(--color-primary-700);
  border-color: var(--color-primary-700);
}

/* ==========================================================================
   FEED
   ========================================================================== */

.feed {
  list-style: none;
  margin: 0;
  padding: 0;
  display: grid;
  gap: var(--space-1);
}

.post {
  display: grid;
  grid-template-columns: 1fr auto;
  gap: var(--space-6);
  align-items: start;
  padding: var(--space-6);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  transition: all var(--transition-fast);
  position: relative;
}

.post::after {
  content: '';
  position: absolute;
  left: 0;
  top: var(--space-4);
  bottom: var(--space-4);
  width: 3px;
  background: var(--surface-subtle);
  border-radius: 2px;
  transition: background var(--transition-fast);
}

.post:hover {
  border-color: var(--border-default);
  box-shadow: var(--shadow-sm);
}

.post.seen {
  opacity: 0.5;
  background: var(--surface-subtle);
}

.post.seen::after {
  background: var(--border-subtle);
}

.post-main {
  min-width: 0;
}

.post-title {
  display: block;
  font-size: var(--text-lg);
  font-weight: var(--weight-semibold);
  line-height: var(--leading-snug);
  color: var(--text-primary);
  text-decoration: none;
  margin-bottom: var(--space-2);
  letter-spacing: var(--tracking-tight);
}

.post-title:hover {
  color: var(--color-primary-600);
}

.post.seen .post-title {
  color: var(--text-muted);
}

.post-meta {
  font-size: var(--text-xs);
  color: var(--text-secondary);
  margin-bottom: var(--space-3);
  font-variant-numeric: tabular-nums;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.meta-item + .meta-item::before {
  content: " • ";
  margin: 0 var(--space-1);
  color: var(--text-muted);
}

/* ==========================================================================
   STATS & BADGES
   ========================================================================== */

.post-stats {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
  align-items: flex-end;
  text-align: right;
}

.stats-row {
  display: flex;
  gap: var(--space-2);
  align-items: center;
  flex-wrap: wrap;
  justify-content: flex-end;
}

.badge {
  display: inline-flex;
  align-items: center;
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  font-variant-numeric: tabular-nums;
  padding: var(--space-1) var(--space-2);
  border-radius: var(--radius-sm);
  white-space: nowrap;
  line-height: 1;
  letter-spacing: var(--tracking-wide);
  text-transform: uppercase;
}

.badge-relevance {
  background: var(--status-high-bg);
  color: var(--status-high-text);
  font-weight: var(--weight-bold);
  font-size: var(--text-sm);
}

.badge-score {
  background: var(--status-medium-bg);
  color: var(--status-medium-text);
}

.badge-comments {
  background: var(--color-primary-100);
  color: var(--color-primary-700);
}

.badge-signal {
  background: var(--signal-bg);
  color: var(--signal-text);
}

.badge-keyword {
  background: var(--keyword-bg);
  color: var(--keyword-text);
}

.btn-seen {
  font-size: var(--text-xs);
  font-weight: var(--weight-medium);
  padding: var(--space-1) var(--space-3);
  border: 1px solid var(--border-default);
  border-radius: var(--radius-sm);
  background: var(--surface-card);
  color: var(--text-secondary);
  cursor: pointer;
  transition: all var(--transition-fast);
  text-transform: uppercase;
  letter-spacing: var(--tracking-wide);
}

.btn-seen:hover {
  background: var(--surface-subtle);
  border-color: var(--border-strong);
}

.post.seen .btn-seen {
  border-color: var(--border-subtle);
  color: var(--text-muted);
  cursor: default;
  opacity: 0.6;
}

/* ==========================================================================
   LOADING & ERROR STATES
   ========================================================================== */

.loading,
.error {
  text-align: center;
  padding: var(--space-8);
  background: var(--surface-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  margin: var(--space-4) 0;
}

.loading {
  color: var(--text-secondary);
  font-style: italic;
}

.error {
  background: var(--status-low-bg);
  color: var(--status-low-text);
  border-color: oklch(0.85 0.08 25);
}

/* ==========================================================================
   RESPONSIVE
   ========================================================================== */

@media (max-width: 768px) {
  .post {
    grid-template-columns: 1fr;
    gap: var(--space-4);
  }

  .post-stats {
    flex-direction: row;
    align-items: flex-start;
    text-align: left;
  }

  .stats-row {
    justify-content: flex-start;
  }

  .controls {
    flex-direction: column;
    align-items: stretch;
  }

  button {
    justify-content: center;
  }

  .post::after {
    left: var(--space-4);
    right: var(--space-4);
    top: 0;
    bottom: auto;
    width: auto;
    height: 3px;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}