/* -----------------------------------------------------------
   Design tokens
----------------------------------------------------------- */
:root {
  --bg: #10132b;
  --surface: #171b3d;
  --surface-hover: #1d2148;
  --border: #262b52;

  --text: #f1f3fa;
  --text-muted: #8b90b3;

  --mint: #3ddc97;
  --coral: #ff6b6b;
  --amber: #ffb454;

  --radius-lg: 16px;
  --radius-md: 10px;
  --radius-sm: 6px;

  --font-display: "Space Grotesk", sans-serif;
  --font-body: "Inter", sans-serif;
  --font-mono: "JetBrains Mono", monospace;

  --transition: 180ms ease;
}

/* -----------------------------------------------------------
   Reset & base
----------------------------------------------------------- */
* {
  box-sizing: border-box;
}

html {
  color-scheme: dark;
}

body {
  margin: 0;
  min-height: 100vh;
  background: var(--bg);
  background-image: radial-gradient(circle at 12% 0%, #1b1f47 0%, var(--bg) 45%);
  color: var(--text);
  font-family: var(--font-body);
  line-height: 1.5;
  -webkit-font-smoothing: antialiased;
}

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

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

/* -----------------------------------------------------------
   Header
----------------------------------------------------------- */
.site-header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 24px clamp(20px, 5vw, 48px) 12px;
}

.brand {
  display: flex;
  align-items: center;
  gap: 10px;
}

.pulse-dot {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: var(--mint);
  box-shadow: 0 0 0 0 rgba(61, 220, 151, 0.6);
  animation: pulse-dot 2.2s ease-out infinite;
}

@keyframes pulse-dot {
  0% {
    box-shadow: 0 0 0 0 rgba(61, 220, 151, 0.55);
  }
  70% {
    box-shadow: 0 0 0 8px rgba(61, 220, 151, 0);
  }
  100% {
    box-shadow: 0 0 0 0 rgba(61, 220, 151, 0);
  }
}

.brand-name {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1.35rem;
  letter-spacing: 0.01em;
}

.brand-name span {
  color: var(--amber);
}

.header-controls {
  display: flex;
  align-items: center;
  gap: 12px;
}

.search-field {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 14px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition);
}

.search-field:focus-within {
  border-color: var(--amber);
}

.search-icon {
  width: 16px;
  height: 16px;
  color: var(--text-muted);
  flex-shrink: 0;
}

.search-field input {
  background: transparent;
  border: none;
  color: var(--text);
  font-family: var(--font-body);
  font-size: 0.9rem;
  width: 160px;
}

.search-field input:focus {
  outline: none;
}

.search-field input::placeholder {
  color: var(--text-muted);
}

.refresh-btn {
  display: flex;
  align-items: center;
  gap: 8px;
  padding: 9px 16px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  color: var(--text);
  font-family: var(--font-body);
  font-weight: 500;
  font-size: 0.9rem;
  cursor: pointer;
  transition: border-color var(--transition), background var(--transition);
}

.refresh-btn:hover {
  border-color: var(--amber);
  background: var(--surface-hover);
}

.refresh-icon {
  width: 15px;
  height: 15px;
  transition: transform 500ms ease;
}

.refresh-btn.is-loading .refresh-icon {
  animation: spin 700ms linear infinite;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.status-line {
  margin: 0 clamp(20px, 5vw, 48px) 20px;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.8rem;
}

/* -----------------------------------------------------------
   Error banner
----------------------------------------------------------- */
.error-banner {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin: 0 clamp(20px, 5vw, 48px) 20px;
  padding: 14px 18px;
  background: rgba(255, 107, 107, 0.08);
  border: 1px solid rgba(255, 107, 107, 0.35);
  border-radius: var(--radius-md);
  color: #ffd7d7;
}

.error-banner p {
  margin: 0;
  font-size: 0.9rem;
}

.error-banner button {
  padding: 7px 14px;
  background: var(--coral);
  border: none;
  border-radius: var(--radius-sm);
  color: #2a0b0b;
  font-weight: 600;
  font-size: 0.85rem;
  cursor: pointer;
}

/* -----------------------------------------------------------
   Grid & cards
----------------------------------------------------------- */
.grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(250px, 1fr));
  gap: 16px;
  padding: 0 clamp(20px, 5vw, 48px) 40px;
}

.coin-card {
  display: flex;
  flex-direction: column;
  gap: 14px;
  padding: 20px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  transition: transform var(--transition), border-color var(--transition);
}

.coin-card:hover {
  transform: translateY(-3px);
  border-color: var(--amber);
}

.coin-card__top {
  display: flex;
  align-items: center;
  gap: 10px;
}

.coin-card__icon {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  flex-shrink: 0;
}

.coin-card__names {
  min-width: 0;
}

.coin-card__symbol {
  margin: 0;
  font-family: var(--font-display);
  font-weight: 600;
  font-size: 1rem;
  letter-spacing: 0.02em;
}

.coin-card__name {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.8rem;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}

.coin-card__price-row {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: 10px;
}

.coin-card__price {
  font-family: var(--font-mono);
  font-size: 1.15rem;
  font-weight: 500;
  font-variant-numeric: tabular-nums;
}

.change-badge {
  display: inline-flex;
  align-items: center;
  gap: 3px;
  padding: 3px 8px;
  border-radius: 999px;
  font-family: var(--font-mono);
  font-size: 0.78rem;
  font-weight: 600;
  white-space: nowrap;
}

.change-badge.up {
  color: var(--mint);
  background: rgba(61, 220, 151, 0.12);
}

.change-badge.down {
  color: var(--coral);
  background: rgba(255, 107, 107, 0.12);
}

.sparkline {
  width: 100%;
  height: 40px;
  display: block;
  overflow: visible;
}

.sparkline path {
  fill: none;
  stroke-width: 1.75;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.sparkline.up path {
  stroke: var(--mint);
}

.sparkline.down path {
  stroke: var(--coral);
}

.coin-card__cap {
  margin: 0;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 0.72rem;
  letter-spacing: 0.02em;
}

/* -----------------------------------------------------------
   Skeleton loading state
----------------------------------------------------------- */
.skeleton-card {
  height: 158px;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border);
  background: linear-gradient(100deg, var(--surface) 30%, var(--surface-hover) 50%, var(--surface) 70%);
  background-size: 200% 100%;
  animation: shimmer 1.4s ease-in-out infinite;
}

@keyframes shimmer {
  0% {
    background-position: 140% 0;
  }
  100% {
    background-position: -40% 0;
  }
}

/* -----------------------------------------------------------
   Empty state & footer
----------------------------------------------------------- */
.empty-state {
  text-align: center;
  color: var(--text-muted);
  padding: 40px 20px 60px;
}

.site-footer {
  padding: 20px clamp(20px, 5vw, 48px) 40px;
  color: var(--text-muted);
  font-size: 0.8rem;
  border-top: 1px solid var(--border);
}

.site-footer p {
  margin: 0;
}

/* -----------------------------------------------------------
   Reduced motion
----------------------------------------------------------- */
@media (prefers-reduced-motion: reduce) {
  .pulse-dot,
  .refresh-btn.is-loading .refresh-icon,
  .skeleton-card {
    animation: none;
  }

  .coin-card {
    transition: none;
  }

  .coin-card:hover {
    transform: none;
  }
}

/* -----------------------------------------------------------
   Small screens
----------------------------------------------------------- */
@media (max-width: 560px) {
  .site-header {
    flex-direction: column;
    align-items: flex-start;
  }

  .header-controls {
    width: 100%;
  }

  .search-field {
    flex: 1;
  }

  .search-field input {
    width: 100%;
  }
}