/* ============================================================
   AQI — Global Air Quality
   ============================================================ */

/* ---------- Design tokens ---------- */
:root {
  --font: "Inter", system-ui, sans-serif;

  /* AQI colour palette — bold, saturated EPA-aligned colours */
  --color-good:          #16a34a;
  --color-moderate:      #ca8a04;
  --color-sensitive:     #ea580c;
  --color-unhealthy:     #dc2626;
  --color-very-unhealthy:#7c3aed;
  --color-hazardous:     #9f1239;

  --color-good-text:          #fff;
  --color-moderate-text:      #fff;
  --color-sensitive-text:     #fff;
  --color-unhealthy-text:     #fff;
  --color-very-unhealthy-text:#fff;
  --color-hazardous-text:     #fff;

  --color-good-bg:          #16a34a;
  --color-moderate-bg:      #ca8a04;
  --color-sensitive-bg:     #ea580c;
  --color-unhealthy-bg:     #dc2626;
  --color-very-unhealthy-bg:#7c3aed;
  --color-hazardous-bg:     #9f1239;
  --color-unknown-bg:       #374151;

  /* UI colours */
  --bg:          #0f1117;
  --surface:     #1a1d27;
  --surface-2:   #22263a;
  --border:      #2e3347;
  --text:        #e8eaf0;
  --text-muted:  #8b92a8;
  --accent:      #4f8ef7;
  --accent-hover:#3a7ae8;
  --aqi-section-bg: rgba(7, 10, 18, 0.55);
  --aqi-section-border: rgba(255, 255, 255, 0.10);
  --aqi-section-fg: rgba(255, 255, 255, 0.95);
  --aqi-section-pill-bg: rgba(255, 255, 255, 0.14);
  --aqi-section-pill-border: rgba(255, 255, 255, 0.22);

  --radius:    12px;
  --radius-sm: 8px;
  --shadow:    0 4px 24px rgba(0,0,0,0.4);
  --transition:0.2s ease;
}

/* ---------- Light theme overrides ---------- */
.theme-light {
  --bg:        #f4f6fb;
  --surface:   #ffffff;
  --surface-2: #eef1f8;
  --border:    #d0d5e8;
  --text:      #1a1d2e;
  --text-muted:#6b7190;
  --shadow:    0 4px 24px rgba(0,0,0,0.10);
  --aqi-section-bg: rgba(255, 255, 255, 0.72);
  --aqi-section-border: rgba(17, 24, 39, 0.10);
  --aqi-section-fg: rgba(17, 24, 39, 0.92);
  --aqi-section-pill-bg: rgba(17, 24, 39, 0.08);
  --aqi-section-pill-border: rgba(17, 24, 39, 0.16);
}

/* ---------- Reset & base ---------- */
*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }

html, body {
  height: 100%;
  /* Background and color live on .app so the theme class controls them */
  font-family: var(--font);
  font-size: 16px;
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: underline; }

/* ---------- Layout ---------- */
.app {
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  background: var(--bg);
  color: var(--text);
  transition: .15s ease background var(--transition), color var(--transition);
}

/* ---- Haze: AQI-level gradient backdrops ---- */
/* Each class is added to .app when data loads — a soft atmospheric glow
   bleeds in from the upper region, referencing the EPA AQI palette.    */

.app--aqi-good {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(22,  163,  74, 0.26), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(22,  163,  74, 0.09), transparent 65%),
    #0f1117;
}
.app--aqi-moderate {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(202, 138,   4, 0.28), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(202, 138,   4, 0.09), transparent 65%),
    #0f1117;
}
.app--aqi-sensitive {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(234,  88,  12, 0.27), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(234,  88,  12, 0.09), transparent 65%),
    #0f1117;
}
.app--aqi-unhealthy {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(220,  38,  38, 0.28), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(220,  38,  38, 0.10), transparent 65%),
    #0f1117;
}
.app--aqi-very-unhealthy {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(124,  58, 237, 0.28), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(124,  58, 237, 0.10), transparent 65%),
    #0f1117;
}
.app--aqi-hazardous {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(159,  18,  57, 0.34), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(159,  18,  57, 0.13), transparent 65%),
    #0f1117;
}

/* Light-mode haze variants — lighter gradients over the warm off-white base */
.theme-light.app--aqi-good {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(22,  163,  74, 0.13), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(22,  163,  74, 0.05), transparent 65%),
    #f4f6fb;
}
.theme-light.app--aqi-moderate {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(202, 138,   4, 0.14), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(202, 138,   4, 0.05), transparent 65%),
    #f4f6fb;
}
.theme-light.app--aqi-sensitive {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(234,  88,  12, 0.13), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(234,  88,  12, 0.05), transparent 65%),
    #f4f6fb;
}
.theme-light.app--aqi-unhealthy {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(220,  38,  38, 0.13), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(220,  38,  38, 0.05), transparent 65%),
    #f4f6fb;
}
.theme-light.app--aqi-very-unhealthy {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(124,  58, 237, 0.13), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(124,  58, 237, 0.05), transparent 65%),
    #f4f6fb;
}
.theme-light.app--aqi-hazardous {
  background:
    radial-gradient(ellipse 90% 55% at 20% 8%,  rgba(159,  18,  57, 0.15), transparent 68%),
    radial-gradient(ellipse 50% 35% at 82% 88%,  rgba(159,  18,  57, 0.06), transparent 65%),
    #f4f6fb;
}

.main {
  flex: 1;
  max-width: 960px;
  width: 100%;
  margin: 0 auto;
  padding: 2rem 1rem;
}

/* ---------- Header ---------- */
.header {
  background: rgba(15, 17, 23, 0.70);
  backdrop-filter: blur(22px);
  -webkit-backdrop-filter: blur(22px);
  border-bottom: 1px solid rgba(255, 255, 255, 0.07);
  padding: 1rem 1.5rem;
  display: flex;
  align-items: center;
  gap: 1.5rem;
  flex-wrap: wrap;
  position: sticky;
  top: 0;
  z-index: 100;
}

.theme-light .header {
  background: rgba(244, 246, 251, 0.78);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
}

.header__brand {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  flex-shrink: 0;
}

.header__brand-logo {
  height: 2.5rem;
  width: auto;
  max-width: min(220px, 42vw);
  object-fit: contain;
  object-position: left center;
  display: block;
}

.header__controls {
  flex: 1;
  display: flex;
  align-items: center;
  gap: 0.75rem;
  min-width: 0;
}

/* AQI level backgrounds */
.aqi-good           { background: var(--color-good-bg);          color: var(--color-good-text); }
.aqi-moderate       { background: var(--color-moderate-bg);      color: var(--color-moderate-text); }
.aqi-sensitive      { background: var(--color-sensitive-bg);     color: var(--color-sensitive-text); }
.aqi-unhealthy      { background: var(--color-unhealthy-bg);     color: var(--color-unhealthy-text); }
.aqi-very-unhealthy { background: var(--color-very-unhealthy-bg);color: var(--color-very-unhealthy-text); }
.aqi-hazardous      { background: var(--color-hazardous-bg);     color: var(--color-hazardous-text); }
.aqi-unknown        { background: var(--color-unknown-bg);       color: #e5e7eb; }

/* ---------- Theme toggle ---------- */
.btn-theme {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  border-radius: var(--radius-sm);
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.12);
  color: var(--text);
  font-size: 1.1rem;
  cursor: pointer;
  flex-shrink: 0;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background var(--transition), border-color var(--transition);
}
.btn-theme:hover {
  background: var(--accent);
  border-color: var(--accent);
}
.theme-light .btn-theme {
  background: rgba(255, 255, 255, 0.60);
  border: 1px solid rgba(0, 0, 0, 0.10);
}

/* ---------- Locate button ---------- */
.btn-locate {
  display: flex;
  align-items: center;
  gap: 0.4rem;
  padding: 0.5rem 1rem;
  background: rgba(255, 255, 255, 0.07);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: var(--radius-sm);
  color: var(--text);
  font-size: 0.875rem;
  font-family: var(--font);
  cursor: pointer;
  white-space: nowrap;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  transition: background var(--transition), border-color var(--transition);
}
.btn-locate:hover {
  background: var(--accent);
  border-color: var(--accent);
}
.theme-light .btn-locate {
  background: rgba(255, 255, 255, 0.60);
  border: 1px solid rgba(0, 0, 0, 0.10);
}
.btn-locate svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

/* ---------- Status panels ---------- */
.status-panel {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  text-align: center;
  gap: 0.75rem;
  padding: 4rem 2rem;
  color: var(--text-muted);
}
.status-panel--error { color: #ff6b6b; }

.status-panel__icon { font-size: 3rem; }
.status-panel__msg  { font-size: 1.1rem; color: var(--text); }
.status-panel__hint { font-size: 0.875rem; color: var(--text-muted); max-width: 400px; }

.status-panel__actions {
  display: flex;
  gap: 0.75rem;
  flex-wrap: wrap;
  justify-content: center;
  margin-top: 0.5rem;
}

.btn-retry {
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--accent);
  color: #fff;
  font-size: 0.875rem;
  font-family: var(--font);
  font-weight: 600;
  cursor: pointer;
  transition: background var(--transition);
}
.btn-retry:hover { background: var(--accent-hover); }

.btn-skip {
  margin-top: 0.5rem;
  padding: 0.5rem 1.25rem;
  border-radius: var(--radius-sm);
  border: 1px solid var(--border);
  background: var(--surface-2);
  color: var(--text-muted);
  font-size: 0.875rem;
  font-family: var(--font);
  cursor: pointer;
  transition: background var(--transition), color var(--transition), border-color var(--transition);
}
.btn-skip:hover {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
}

/* ---------- Spinner ---------- */
.spinner {
  width: 48px;
  height: 48px;
  border: 4px solid var(--border);
  border-top-color: var(--accent);
  border-radius: 50%;
  animation: spin 0.9s linear infinite;
}

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

/* ---------- Skeleton loader ---------- */
@keyframes shimmer {
  0%   { background-position: -600px 0; }
  100% { background-position:  600px 0; }
}

.skel {
  border-radius: var(--radius-sm);
  background: linear-gradient(
    90deg,
    var(--surface-2) 25%,
    var(--border)    50%,
    var(--surface-2) 75%
  );
  background-size: 600px 100%;
  animation: shimmer 1.4s infinite linear;
}

.skel--title  { height: 22px; width: 55%; }
.skel--chip   { height: 22px; width: 72px; border-radius: 999px; }
.skel--circle { width: 130px; height: 130px; border-radius: 50%; flex-shrink: 0; }
.skel--bar    { height: 32px; border-radius: var(--radius-sm); margin-top: 1.25rem; }
.skel--line   { height: 14px; }
.skel--line-lg { width: 80%; }
.skel--line-md { width: 55%; }
.skel--line-sm { width: 35%; }
.skel--tile   { height: 90px; border-radius: var(--radius-sm); }

.skeleton-card {
  border-radius: var(--radius);
  padding: 1.75rem;
  background: rgba(12, 15, 25, 0.52);
  backdrop-filter: blur(24px);
  -webkit-backdrop-filter: blur(24px);
  border: 1px solid rgba(255, 255, 255, 0.10);
  box-shadow:
    0 8px 40px rgba(0, 0, 0, 0.40),
    inset 0 1px 0 rgba(255, 255, 255, 0.07);
}

.theme-light .skeleton-card {
  background: rgba(255, 255, 255, 0.68);
  border: 1px solid rgba(255, 255, 255, 0.80);
  box-shadow: 0 8px 40px rgba(0, 0, 0, 0.08);
}

.skeleton-card__header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 1.25rem;
}

.skeleton-card__body {
  display: flex;
  align-items: center;
  gap: 2rem;
  margin-bottom: 1.5rem;
}

.skeleton-card__lines {
  flex: 1;
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.skeleton-card__grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(130px, 1fr));
  gap: 0.75rem;
}

/* ---------- Dashboard ---------- */
.dashboard {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

/* ---------- Footer ---------- */
.footer {
  display: flex;
  align-items: center;
  justify-content: center;
  flex-wrap: wrap;
  gap: 0.5rem;
  padding: 1.25rem;
  font-size: 0.85rem;
  color: var(--text-muted);
  border-top: 1px solid var(--border);
}

.footer__name {
  font-weight: 600;
  color: var(--text);
}

.footer__sep {
  color: var(--border);
}

.footer a {
  display: inline-flex;
  align-items: center;
  gap: 0.3rem;
  color: var(--text-muted);
  text-decoration: none;
  transition: color var(--transition);
}

.footer a:hover {
  color: var(--accent);
}