/* ============================================
   TechNews — Editorial News Reader
   ============================================ */

:root {
  /* Light & Clean palette */
  --bg-primary: #F2F3F5;
  --bg-secondary: #E8E9EC;
  --bg-card: #FFFFFF;
  --bg-card-hover: #FAFAFA;
  --text-primary: #1A1A1A;
  --text-secondary: #5F6368;
  --text-tertiary: #9AA0A6;
  --accent: #E7000E;
  --accent-soft: #E7000E18;
  --accent-hover: #C5000B;
  --border: #DDDFE2;
  --border-light: #E8E9EC;
  --shadow-sm: 0 1px 3px rgba(26, 23, 20, 0.04);
  --shadow-md: 0 4px 16px rgba(26, 23, 20, 0.06);
  --shadow-lg: 0 8px 32px rgba(26, 23, 20, 0.08);
  --shadow-card: 0 1px 4px rgba(26,23,20,0.04), 0 4px 16px rgba(26,23,20,0.03);
  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --font-display: 'Ubuntu', -apple-system, sans-serif;
  --font-body: 'Ubuntu', -apple-system, sans-serif;
  --safe-top: env(safe-area-inset-top, 0px);
  --safe-bottom: env(safe-area-inset-bottom, 0px);
  --safe-left: env(safe-area-inset-left, 0px);
  --safe-right: env(safe-area-inset-right, 0px);
}

[data-theme="dark"] {
  --bg-primary: #141210;
  --bg-secondary: #1E1C19;
  --bg-card: #222019;
  --bg-card-hover: #2A2720;
  --text-primary: #F0EBE3;
  --text-secondary: #A09890;
  --text-tertiary: #6B6560;
  --accent: #FF3B3B;
  --accent-soft: #FF3B3B20;
  --accent-hover: #FF5252;
  --border: #2E2B26;
  --border-light: #252320;
  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.2);
  --shadow-md: 0 4px 16px rgba(0, 0, 0, 0.3);
  --shadow-lg: 0 8px 32px rgba(0, 0, 0, 0.4);
  --shadow-card: 0 1px 4px rgba(0,0,0,0.2), 0 4px 16px rgba(0,0,0,0.15);
}

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

html {
  -webkit-text-size-adjust: 100%;
  -webkit-tap-highlight-color: transparent;
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background: var(--bg-primary);
  color: var(--text-primary);
  line-height: 1.5;
  min-height: 100vh;
  min-height: 100dvh;
  overscroll-behavior-y: contain;
  transition: background-color 0.4s ease, color 0.4s ease;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Subtle paper texture overlay */
body::before {
  content: '';
  position: fixed;
  inset: 0;
  pointer-events: none;
  z-index: 9999;
  opacity: 0.025;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
  background-size: 256px 256px;
}

[data-theme="dark"] body::before {
  opacity: 0.04;
}

/* ---- Pull to Refresh ---- */
.pull-indicator {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 12px;
  padding-top: calc(12px + var(--safe-top));
  background: var(--accent);
  color: #fff;
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.02em;
  transform: translateY(-100%);
  transition: transform 0.3s cubic-bezier(0.22, 1, 0.36, 1);
  z-index: 1000;
}

.pull-indicator.visible {
  transform: translateY(0);
}

.pull-spinner {
  width: 18px;
  height: 18px;
  animation: spin 1s linear infinite;
}

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

/* ---- Header ---- */
.app-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: var(--bg-primary);
  padding: 0 20px;
  padding-top: calc(16px + var(--safe-top));
  padding-left: calc(20px + var(--safe-left));
  padding-right: calc(20px + var(--safe-right));
  border-bottom: 1px solid var(--border);
  transition: background-color 0.4s ease;
}

/* Frosted glass effect */
@supports (backdrop-filter: blur(20px)) {
  .app-header {
    background: color-mix(in srgb, var(--bg-primary) 80%, transparent);
    backdrop-filter: blur(20px) saturate(180%);
    -webkit-backdrop-filter: blur(20px) saturate(180%);
  }
}

.header-top {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  margin-bottom: 16px;
}

.masthead {
  flex: 1;
}

.logo {
  font-family: var(--font-display);
  font-size: 32px;
  font-weight: 700;
  letter-spacing: -0.01em;
  color: var(--text-primary);
  line-height: 1.1;
}

.edition-date {
  font-size: 13px;
  color: var(--text-tertiary);
  margin-top: 4px;
  font-weight: 400;
  letter-spacing: 0.03em;
  text-transform: uppercase;
}

/* ---- Theme Toggle ---- */
.theme-toggle {
  background: var(--bg-secondary);
  border: 1px solid var(--border);
  border-radius: 50%;
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  color: var(--text-secondary);
  transition: all 0.2s ease;
  flex-shrink: 0;
  margin-top: 4px;
}

.theme-toggle:hover {
  background: var(--bg-card);
  color: var(--accent);
  border-color: var(--accent);
}

.theme-toggle svg {
  width: 18px;
  height: 18px;
}

.icon-moon { display: none; }
[data-theme="dark"] .icon-sun { display: none; }
[data-theme="dark"] .icon-moon { display: block; }

/* ---- Edition Toggle ---- */
.edition-toggle {
  display: flex;
  gap: 8px;
  margin-bottom: 14px;
}

.edition-btn {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 16px;
  border: 1.5px solid var(--border);
  border-radius: var(--radius-md);
  background: transparent;
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.25s ease;
  letter-spacing: 0.01em;
}

.edition-btn svg {
  flex-shrink: 0;
  opacity: 0.6;
  transition: opacity 0.25s ease;
}

.edition-btn:hover {
  border-color: var(--accent);
  color: var(--accent);
}

.edition-btn.active {
  background: var(--accent);
  border-color: var(--accent);
  color: #fff;
  box-shadow: 0 2px 12px rgba(231, 0, 14, 0.25);
}

.edition-btn.active svg {
  opacity: 1;
}

[data-theme="dark"] .edition-btn.active {
  box-shadow: 0 2px 12px rgba(255, 59, 59, 0.2);
}

/* ---- Source Filter Pills ---- */
.source-filters {
  display: flex;
  gap: 6px;
  overflow-x: auto;
  -webkit-overflow-scrolling: touch;
  scrollbar-width: none;
  padding-bottom: 14px;
  margin: 0 -20px;
  padding-left: 20px;
  padding-right: 20px;
}

.source-filters::-webkit-scrollbar { display: none; }

.source-pill {
  flex-shrink: 0;
  padding: 6px 14px;
  border: 1.5px solid var(--border);
  border-radius: 100px;
  background: transparent;
  color: var(--text-secondary);
  font-family: var(--font-body);
  font-size: 12.5px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.source-pill:hover {
  border-color: var(--text-tertiary);
  color: var(--text-primary);
}

.source-pill.active {
  background: var(--text-primary);
  border-color: var(--text-primary);
  color: var(--bg-primary);
}

/* Source-specific colors */
.source-pill[data-source="Hacker News"].active { background: #FF6600; border-color: #FF6600; color: #fff; }
.source-pill[data-source="TechCrunch"].active { background: #0A9E01; border-color: #0A9E01; color: #fff; }
.source-pill[data-source="The Verge"].active { background: #5100FF; border-color: #5100FF; color: #fff; }
.source-pill[data-source="Ars Technica"].active { background: #FF4E00; border-color: #FF4E00; color: #fff; }
.source-pill[data-source="Wired"].active { background: #000; border-color: #000; color: #fff; }
[data-theme="dark"] .source-pill[data-source="Wired"].active { background: #fff; border-color: #fff; color: #000; }
.source-pill[data-source="Smashing Magazine"].active { background: #D33A2C; border-color: #D33A2C; color: #fff; }
.source-pill[data-source="The Register"].active { background: #0064A0; border-color: #0064A0; color: #fff; }
.source-pill[data-source="Euronews Tech"].active { background: #023882; border-color: #023882; color: #fff; }
.source-pill[data-source="Sifted"].active { background: #1E1E1E; border-color: #1E1E1E; color: #fff; }
.source-pill[data-source="Digitec"].active { background: #441891; border-color: #441891; color: #fff; }
.source-pill[data-source="SwissInfo SciTech"].active { background: #D20000; border-color: #D20000; color: #fff; }
.source-pill[data-source="Startupticker"].active { background: #00824B; border-color: #00824B; color: #fff; }
.source-pill[data-source="t3n"].active { background: #EF4423; border-color: #EF4423; color: #fff; }
.source-pill[data-source="Heise"].active { background: #00508C; border-color: #00508C; color: #fff; }
.source-pill[data-source="GameStar"].active { background: #141414; border-color: #141414; color: #fff; }

/* ---- News Feed ---- */
.news-feed {
  padding: 20px;
  padding-left: calc(20px + var(--safe-left));
  padding-right: calc(20px + var(--safe-right));
  padding-bottom: calc(80px + var(--safe-bottom));
  max-width: 680px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 16px;
}

/* ---- Hero Card (first article) ---- */
.card.hero {
  border-radius: var(--radius-lg);
}

.card.hero .card-image {
  height: 240px;
}

.card.hero .card-title {
  font-size: 22px;
  line-height: 1.25;
}

.card.hero .card-desc {
  display: -webkit-box;
  -webkit-line-clamp: 3;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ---- Card ---- */
.card {
  background: var(--bg-card);
  border-radius: var(--radius-md);
  overflow: hidden;
  border: 1px solid var(--border-light);
  box-shadow: var(--shadow-card);
  transition: all 0.3s cubic-bezier(0.22, 1, 0.36, 1);
  cursor: pointer;
  text-decoration: none;
  color: inherit;
  display: block;
  animation: cardIn 0.5s cubic-bezier(0.22, 1, 0.36, 1) backwards;
}

.card:hover {
  box-shadow: var(--shadow-lg);
  transform: translateY(-2px);
  border-color: var(--border);
}

.card:active {
  transform: scale(0.985);
  box-shadow: var(--shadow-sm);
}

@keyframes cardIn {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
}

.card:nth-child(1) { animation-delay: 0.05s; }
.card:nth-child(2) { animation-delay: 0.1s; }
.card:nth-child(3) { animation-delay: 0.15s; }
.card:nth-child(4) { animation-delay: 0.2s; }
.card:nth-child(5) { animation-delay: 0.25s; }
.card:nth-child(6) { animation-delay: 0.3s; }
.card:nth-child(7) { animation-delay: 0.35s; }
.card:nth-child(8) { animation-delay: 0.38s; }

/* Image */
.card-image {
  width: 100%;
  height: 180px;
  background: var(--bg-secondary);
  position: relative;
  overflow: hidden;
}

.card-image img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  transition: transform 0.5s cubic-bezier(0.22, 1, 0.36, 1);
}

.card:hover .card-image img {
  transform: scale(1.04);
}

/* Gradient overlay on image */
.card-image::after {
  content: '';
  position: absolute;
  bottom: 0;
  left: 0;
  right: 0;
  height: 60%;
  background: linear-gradient(to top, rgba(0,0,0,0.15), transparent);
  pointer-events: none;
}

/* No-image placeholder */
.card-image.no-image {
  height: 6px;
  background: var(--border-light);
}

.card-image.no-image::after { display: none; }

/* Source badge floating on image */
.card-source-badge {
  position: absolute;
  top: 12px;
  left: 12px;
  z-index: 2;
  display: flex;
  align-items: center;
  gap: 5px;
  padding: 4px 10px;
  border-radius: 100px;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  color: #fff;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.no-image .card-source-badge {
  display: none;
}

/* Source badge colors */
.badge-hn { background: rgba(255, 102, 0, 0.85); }
.badge-tc { background: rgba(10, 158, 1, 0.85); }
.badge-verge { background: rgba(81, 0, 255, 0.85); }
.badge-ars { background: rgba(255, 78, 0, 0.85); }
.badge-wired { background: rgba(0, 0, 0, 0.7); }
.badge-smashing { background: rgba(211, 58, 44, 0.85); }
.badge-register { background: rgba(0, 100, 160, 0.85); }
.badge-euronews { background: rgba(2, 56, 130, 0.85); }
.badge-sifted { background: rgba(30, 30, 30, 0.8); }
.badge-digitec { background: rgba(68, 24, 145, 0.85); }
.badge-swissinfo { background: rgba(210, 0, 0, 0.85); }
.badge-startupticker { background: rgba(0, 130, 75, 0.85); }
.badge-t3n { background: rgba(239, 68, 35, 0.85); }
.badge-heise { background: rgba(0, 80, 140, 0.85); }
.badge-gamestar { background: rgba(20, 20, 20, 0.85); }

/* Card body */
.card-body {
  padding: 16px;
}

.card-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  margin-bottom: 8px;
}

.card-source-inline {
  font-size: 11.5px;
  font-weight: 600;
  letter-spacing: 0.05em;
  text-transform: uppercase;
  color: var(--accent);
}

.card-time {
  font-size: 12px;
  color: var(--text-tertiary);
  font-weight: 400;
}

.card-title {
  font-family: var(--font-display);
  font-size: 18px;
  font-weight: 700;
  line-height: 1.3;
  color: var(--text-primary);
  margin-bottom: 6px;
}

.card-desc {
  font-size: 14px;
  line-height: 1.55;
  color: var(--text-secondary);
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

/* ---- Compact card variant (no image, inline layout) ---- */
.card.compact .card-image { display: none; }
.card.compact .card-body { padding: 14px 16px; }

/* ---- Skeleton Loading ---- */
.skeleton .card-image {
  background: var(--bg-secondary);
}

.skeleton .card-body {
  padding: 16px;
  display: flex;
  flex-direction: column;
  gap: 10px;
}

.sk-line {
  height: 14px;
  border-radius: 7px;
  background: linear-gradient(90deg, var(--bg-secondary) 25%, var(--border-light) 50%, var(--bg-secondary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
}

.sk-line.w80 { width: 80%; height: 18px; }
.sk-line.w60 { width: 60%; }
.sk-line.w40 { width: 40%; }

@keyframes shimmer {
  0% { background-position: 200% 0; }
  100% { background-position: -200% 0; }
}

/* ---- Update Bar ---- */
.update-bar {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  padding: 10px 20px;
  padding-bottom: calc(10px + var(--safe-bottom));
  background: var(--bg-secondary);
  border-top: 1px solid var(--border);
  text-align: center;
  font-size: 12px;
  color: var(--text-tertiary);
  z-index: 100;
  transition: background-color 0.4s ease;
}

@supports (backdrop-filter: blur(12px)) {
  .update-bar {
    background: color-mix(in srgb, var(--bg-secondary) 80%, transparent);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
  }
}

/* ---- Empty / Error States ---- */
.state-message {
  text-align: center;
  padding: 60px 20px;
  animation: cardIn 0.5s ease backwards;
}

.state-message .state-icon {
  font-size: 48px;
  margin-bottom: 16px;
  opacity: 0.4;
}

.state-message h2 {
  font-family: var(--font-display);
  font-size: 22px;
  font-weight: 400;
  margin-bottom: 8px;
  color: var(--text-primary);
}

.state-message p {
  font-size: 14px;
  color: var(--text-secondary);
  max-width: 280px;
  margin: 0 auto;
  line-height: 1.6;
}

.state-message button {
  margin-top: 20px;
  padding: 10px 24px;
  border: none;
  border-radius: var(--radius-md);
  background: var(--accent);
  color: #fff;
  font-family: var(--font-body);
  font-size: 14px;
  font-weight: 500;
  cursor: pointer;
  transition: background 0.2s ease;
}

.state-message button:hover {
  background: var(--accent-hover);
}

/* ---- Responsive ---- */
@media (min-width: 600px) {
  .news-feed {
    padding: 28px;
  }

  .card.hero .card-image {
    height: 300px;
  }

  .card.hero .card-title {
    font-size: 26px;
  }

  .logo {
    font-size: 38px;
  }
}

@media (min-width: 900px) {
  .news-feed {
    max-width: 720px;
    padding: 32px;
  }
}

/* ---- Accessibility ---- */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01s !important;
    transition-duration: 0.01s !important;
  }
}

/* Focus styles */
:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

button:focus:not(:focus-visible) {
  outline: none;
}