/* ===================================
   Nebula Tech Blog · 星云科技博客
   =================================== */

/* ---------- CSS Variables ---------- */
:root {
  --bg-deep: #0a0a0f;
  --bg-primary: #0d0d1a;
  --bg-card: #111122;
  --bg-card-hover: #151530;
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-glow: rgba(0, 255, 255, 0.15);
  --text-primary: #e8e8f0;
  --text-secondary: #8888a0;
  --text-muted: #555570;
  --accent: #00e5ff;
  --accent-glow: rgba(0, 229, 255, 0.3);
  --accent2: #b44dff;
  --accent2-glow: rgba(180, 77, 255, 0.3);
  --accent3: #ff3cac;
  --gradient-1: linear-gradient(135deg, #00e5ff, #0091ff);
  --gradient-2: linear-gradient(135deg, #b44dff, #ff3cac);
  --gradient-3: linear-gradient(135deg, #00e5ff, #b44dff);
  --font-mono: 'Cascadia Code', 'Fira Code', 'Source Code Pro', 'Consolas', 'Courier New', monospace;
  --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', 'WenQuanYi Micro Hei', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --radius: 12px;
  --radius-lg: 20px;
  --shadow-glow: 0 0 30px rgba(0, 229, 255, 0.1);
  --shadow-glow-strong: 0 0 60px rgba(0, 229, 255, 0.2);
  --transition: 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

/* Light theme overrides */
body.light {
  --bg-deep: #f0f2f7;
  --bg-primary: #f8f9fc;
  --bg-card: #ffffff;
  --bg-card-hover: #f0f2fa;
  --border-subtle: rgba(0, 0, 0, 0.08);
  --border-glow: rgba(0, 140, 255, 0.2);
  --text-primary: #1a1a2e;
  --text-secondary: #555570;
  --text-muted: #999aab;
  --accent: #0077ff;
  --accent2: #7c3aed;
  --accent3: #e04090;
  --font-mono: 'Cascadia Code', 'Fira Code', 'Source Code Pro', 'Consolas', 'Courier New', monospace;
  --font-sans: 'PingFang SC', 'Microsoft YaHei', 'Hiragino Sans GB', 'WenQuanYi Micro Hei', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --shadow-glow: 0 0 30px rgba(0, 119, 255, 0.08);
  --shadow-glow-strong: 0 0 60px rgba(0, 119, 255, 0.12);
}

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

html {
  scroll-behavior: smooth;
  scrollbar-width: thin;
  scrollbar-color: var(--accent) var(--bg-deep);
}

::-webkit-scrollbar {
  width: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-deep);
}
::-webkit-scrollbar-thumb {
  background: var(--accent);
  border-radius: 3px;
}

body {
  font-family: var(--font-sans);
  background: var(--bg-deep);
  color: var(--text-primary);
  line-height: 1.7;
  overflow-x: hidden;
  -webkit-font-smoothing: antialiased;
}

a {
  color: inherit;
  text-decoration: none;
}

ul { list-style: none; }

img { max-width: 100%; display: block; }

/* ---------- Particle Canvas ---------- */
#particle-canvas {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 0;
  opacity: 0.6;
}

body.light #particle-canvas {
  opacity: 0.25;
}


/* ---------- Navbar ---------- */
.navbar {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 1000;
  padding: 0 2rem;
  transition: var(--transition);
}

.navbar.scrolled {
  background: rgba(10, 10, 15, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
}

body.light .navbar.scrolled {
  background: rgba(245, 247, 250, 0.85);
}

.nav-inner {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 72px;
}

/* Logo */
.logo {
  font-family: var(--font-mono);
  font-size: 1.35rem;
  font-weight: 700;
  display: flex;
  align-items: center;
  gap: 1px;
  transition: var(--transition);
}

.logo:hover { transform: scale(1.03); }

.logo-bracket { color: var(--accent); font-weight: 300; }
.logo-text { color: var(--text-primary); }
.logo-dot {
  background: var(--gradient-2);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}
.logo-sub {
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* Nav Links */
.nav-links {
  display: flex;
  gap: 2rem;
}

.nav-item {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--text-secondary);
  transition: var(--transition);
  position: relative;
  padding: 0.25rem 0;
}

.nav-item .nav-num {
  color: var(--accent);
  font-size: 0.7rem;
  margin-right: 4px;
  opacity: 0;
  transform: translateX(-5px);
  transition: var(--transition);
}

.nav-item:hover .nav-num,
.nav-item.active .nav-num {
  opacity: 1;
  transform: translateX(0);
}

.nav-item::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 2px;
  background: var(--gradient-1);
  border-radius: 1px;
  transition: width var(--transition);
}

.nav-item:hover::after,
.nav-item.active::after {
  width: 100%;
}

.nav-item:hover,
.nav-item.active {
  color: var(--text-primary);
}

/* Nav Actions */
.nav-actions {
  display: flex;
  gap: 0.5rem;
  align-items: center;
}

.btn-search,
.btn-theme {
  background: none;
  border: 1px solid var(--border-subtle);
  color: var(--text-secondary);
  width: 40px;
  height: 40px;
  border-radius: 50%;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: var(--transition);
}

.btn-search:hover,
.btn-theme:hover {
  color: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 15px var(--accent-glow);
}

/* Hamburger */
.hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.hamburger span {
  width: 24px;
  height: 2px;
  background: var(--text-primary);
  border-radius: 1px;
  transition: var(--transition);
}

.hamburger.active span:nth-child(1) {
  transform: rotate(45deg) translate(5px, 5px);
}
.hamburger.active span:nth-child(2) {
  opacity: 0;
}
.hamburger.active span:nth-child(3) {
  transform: rotate(-45deg) translate(5px, -5px);
}

/* ---------- Search Overlay ---------- */
.search-overlay {
  position: fixed;
  inset: 0;
  z-index: 2000;
  background: rgba(5, 5, 15, 0.95);
  backdrop-filter: blur(10px);
  display: flex;
  align-items: flex-start;
  justify-content: center;
  padding-top: 20vh;
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--transition);
}

.search-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.search-modal {
  width: 100%;
  max-width: 600px;
  text-align: center;
}

.search-input {
  width: 100%;
  background: transparent;
  border: none;
  border-bottom: 2px solid var(--border-glow);
  color: var(--text-primary);
  font-size: 2rem;
  font-family: var(--font-mono);
  padding: 1rem 0;
  outline: none;
  transition: border-color var(--transition);
}

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

.search-input:focus {
  border-bottom-color: var(--accent);
}

.search-shortcut {
  margin-top: 1rem;
  color: var(--text-muted);
  font-size: 0.85rem;
  font-family: var(--font-mono);
}

.search-shortcut kbd {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: 4px;
  padding: 2px 8px;
  font-size: 0.8rem;
  color: var(--accent);
}

/* ---------- Main Content ---------- */
main {
  position: relative;
  z-index: 1;
  max-width: 1280px;
  margin: 0 auto;
  padding: 0 2rem;
}

/* ---------- Hero Section ---------- */
.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 4rem;
  padding: 120px 0 80px;
  position: relative;
}

.hero-content {
  flex: 1;
  max-width: 620px;
}

.hero-badge {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  letter-spacing: 3px;
  color: var(--accent);
  border: 1px solid var(--border-glow);
  border-radius: 50px;
  padding: 6px 20px;
  margin-bottom: 2rem;
  animation: badgePulse 2s ease-in-out infinite;
}

.badge-dot {
  width: 6px;
  height: 6px;
  background: var(--accent);
  border-radius: 50%;
  box-shadow: 0 0 8px var(--accent);
  animation: dotBlink 1.5s ease-in-out infinite;
}

@keyframes badgePulse {
  0%, 100% { box-shadow: 0 0 0 0 var(--accent-glow); }
  50% { box-shadow: 0 0 0 10px transparent; }
}

@keyframes dotBlink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0.3; }
}

.hero-title {
  font-size: 3.5rem;
  font-weight: 900;
  line-height: 1.2;
  margin-bottom: 1.5rem;
}

.title-line {
  display: block;
}

.title-line.accent {
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.cursor {
  font-weight: 300;
  animation: blink 1s step-end infinite;
  color: var(--accent);
  -webkit-text-fill-color: var(--accent);
  background: none;
  -webkit-background-clip: unset;
  background-clip: unset;
}

@keyframes blink {
  0%, 100% { opacity: 1; }
  50% { opacity: 0; }
}

.hero-desc {
  color: var(--text-secondary);
  font-size: 1.1rem;
  line-height: 1.8;
  margin-bottom: 2.5rem;
  font-weight: 300;
}

.hero-actions {
  display: flex;
  gap: 1rem;
  margin-bottom: 4rem;
}

.btn-primary {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--gradient-1);
  color: #000;
  font-weight: 600;
  padding: 14px 28px;
  border-radius: 50px;
  font-size: 0.95rem;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 10px 40px var(--accent-glow);
}

.btn-outline {
  display: inline-flex;
  align-items: center;
  padding: 14px 28px;
  border: 1px solid var(--border-glow);
  border-radius: 50px;
  font-weight: 500;
  font-size: 0.95rem;
  color: var(--text-primary);
  transition: var(--transition);
}

.btn-outline:hover {
  border-color: var(--accent);
  background: rgba(0, 229, 255, 0.05);
  box-shadow: 0 0 20px var(--accent-glow);
}

/* Hero Stats */
.hero-stats {
  display: flex;
  align-items: center;
  gap: 2rem;
}

.stat {
  text-align: center;
}

.stat-num {
  font-family: var(--font-mono);
  font-size: 2rem;
  font-weight: 700;
  background: var(--gradient-1);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  display: block;
}

.stat-label {
  font-size: 0.85rem;
  color: var(--text-muted);
}

.stat-divider {
  width: 1px;
  height: 40px;
  background: var(--border-subtle);
}

/* Hero Visual */
.hero-visual {
  flex: 1;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  height: 450px;
}

.glowing-sphere {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background: radial-gradient(circle at 40% 40%, rgba(0, 229, 255, 0.4), rgba(180, 77, 255, 0.3), transparent 70%);
  filter: blur(20px);
  animation: sphereFloat 6s ease-in-out infinite;
}

.orb-ring {
  position: absolute;
  border-radius: 50%;
  border: 1px solid var(--border-glow);
  animation: ringRotate 10s linear infinite;
}

.ring-1 {
  width: 280px;
  height: 280px;
  border-color: rgba(0, 229, 255, 0.2);
}
.ring-2 {
  width: 350px;
  height: 350px;
  border-color: rgba(180, 77, 255, 0.15);
  animation-duration: 15s;
  animation-direction: reverse;
}
.ring-3 {
  width: 420px;
  height: 420px;
  border-color: rgba(255, 60, 172, 0.1);
  animation-duration: 20s;
}

@keyframes sphereFloat {
  0%, 100% { transform: translateY(0) scale(1); }
  50% { transform: translateY(-20px) scale(1.05); }
}

@keyframes ringRotate {
  from { transform: rotate(0deg); }
  to { transform: rotate(360deg); }
}

/* Scroll Indicator */
.scroll-indicator {
  position: absolute;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  letter-spacing: 3px;
  color: var(--text-muted);
}

.scroll-line {
  width: 1px;
  height: 40px;
  background: linear-gradient(to bottom, var(--accent), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 0.3; height: 40px; }
  50% { opacity: 1; height: 60px; }
}

/* ---------- Section Header ---------- */
.section-header {
  display: flex;
  align-items: center;
  gap: 1.5rem;
  margin-bottom: 3rem;
}

.section-title {
  font-size: 2rem;
  font-weight: 700;
  white-space: nowrap;
}

.title-prefix {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  font-weight: 400;
  display: block;
  margin-bottom: 4px;
}

.section-line {
  flex: 1;
  height: 1px;
  background: linear-gradient(90deg, var(--border-glow), transparent);
}

.view-all {
  font-family: var(--font-mono);
  font-size: 0.85rem;
  color: var(--accent);
  white-space: nowrap;
  transition: var(--transition);
}

.view-all:hover { color: var(--text-primary); }

/* ---------- Featured Grid ---------- */
.featured {
  padding: 80px 0;
}

.featured-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.featured-main {
  grid-column: span 2;
  display: grid;
  grid-template-columns: 1fr 1fr;
}

.featured-main .card-image {
  border-radius: var(--radius-lg) 0 0 var(--radius-lg);
}

.featured-main .card-body {
  border-radius: 0 var(--radius-lg) var(--radius-lg) 0;
}

/* Blog Card */
.blog-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: all var(--transition);
  position: relative;
}

.blog-card:hover {
  transform: translateY(-4px);
  background: var(--bg-card-hover);
  border-color: var(--border-glow);
  box-shadow: var(--shadow-glow-strong);
}

.card-image {
  position: relative;
  height: 200px;
  overflow: hidden;
}

.featured-main .card-image {
  height: 100%;
}

.card-img-placeholder {
  width: 100%;
  height: 100%;
  position: relative;
}

.img-ai {
  background: linear-gradient(135deg, #0a1628, #1a2744, #0d1f3c);
}
.img-quantum {
  background: linear-gradient(135deg, #1a0a28, #2d1a44, #1f0d3c);
}
.img-web3 {
  background: linear-gradient(135deg, #0a2816, #1a442a, #0d3c1f);
}
.img-rust {
  background: linear-gradient(135deg, #28160a, #44301a, #3c2a0d);
}
.img-space {
  background: linear-gradient(135deg, #0a0a28, #1a1a44, #0d0d3c);
}
.img-security {
  background: linear-gradient(135deg, #280a16, #441a2a, #3c0d1f);
}

.card-img-placeholder::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(circle at 30% 50%, rgba(0, 229, 255, 0.1) 0%, transparent 60%),
    radial-gradient(circle at 70% 50%, rgba(180, 77, 255, 0.08) 0%, transparent 60%);
}

.card-img-placeholder::after {
  content: '';
  position: absolute;
  inset: 0;
  background-image:
    linear-gradient(rgba(0, 229, 255, 0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(0, 229, 255, 0.04) 1px, transparent 1px);
  background-size: 40px 40px;
}

.card-category {
  position: absolute;
  top: 1rem;
  left: 1rem;
  font-family: var(--font-mono);
  font-size: 0.7rem;
  background: rgba(0, 0, 0, 0.7);
  backdrop-filter: blur(10px);
  border: 1px solid var(--border-glow);
  color: var(--accent);
  padding: 4px 12px;
  border-radius: 50px;
}

.card-body {
  padding: 1.5rem;
}

.card-meta {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.meta-divider {
  margin: 0 8px;
  color: var(--border-subtle);
}

.card-title {
  font-size: 1.2rem;
  font-weight: 700;
  margin-bottom: 0.75rem;
  line-height: 1.5;
}

.card-title a {
  transition: var(--transition);
  background: linear-gradient(to right, var(--text-primary), var(--text-primary) 50%, var(--accent) 50%);
  background-size: 200% 100%;
  background-position: 0 0;
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.card-title a:hover {
  background-position: -100% 0;
}

.card-excerpt {
  color: var(--text-secondary);
  font-size: 0.9rem;
  line-height: 1.7;
  display: -webkit-box;
  -webkit-line-clamp: 2;
  -webkit-box-orient: vertical;
  overflow: hidden;
  margin-bottom: 1.25rem;
}

.card-footer {
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.author {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  font-size: 0.85rem;
  color: var(--text-secondary);
}

.author-avatar {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--gradient-3);
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  font-size: 0.85rem;
  color: #fff;
}

.card-tags {
  display: flex;
  gap: 6px;
}

.tag {
  font-family: var(--font-mono);
  font-size: 0.7rem;
  padding: 3px 10px;
  border-radius: 50px;
  background: rgba(0, 229, 255, 0.08);
  color: var(--accent);
  border: 1px solid rgba(0, 229, 255, 0.12);
}

/* ---------- Categories ---------- */
.categories {
  padding: 80px 0;
}

.category-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
}

.category-card {
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 2rem;
  text-align: center;
  transition: all var(--transition);
  position: relative;
  overflow: hidden;
}

.category-card::before {
  content: '';
  position: absolute;
  top: -50%;
  left: -50%;
  width: 200%;
  height: 200%;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 60%);
  opacity: 0;
  transition: opacity var(--transition);
}

.category-card:hover {
  transform: translateY(-4px);
  border-color: var(--accent);
  box-shadow: var(--shadow-glow);
}

.category-card:hover::before {
  opacity: 0.06;
}

.category-icon {
  width: 70px;
  height: 70px;
  margin: 0 auto 1rem;
  background: rgba(0, 229, 255, 0.05);
  border: 1px solid var(--border-glow);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--accent);
  transition: all var(--transition);
}

.category-card:hover .category-icon {
  color: #fff;
  background: rgba(0, 229, 255, 0.15);
  box-shadow: 0 0 25px var(--accent-glow);
}

.category-card h3 {
  font-size: 1.1rem;
  font-weight: 600;
  margin-bottom: 4px;
}

.cat-count {
  font-family: var(--font-mono);
  font-size: 0.8rem;
  color: var(--text-muted);
}

/* ---------- Subscribe ---------- */
.subscribe {
  padding: 80px 0 100px;
}

.subscribe-card {
  position: relative;
  background: var(--bg-card);
  border: 1px solid var(--border-subtle);
  border-radius: var(--radius-lg);
  padding: 4rem 2rem;
  text-align: center;
  overflow: hidden;
}

.subscribe-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  width: 500px;
  height: 500px;
  background: radial-gradient(circle, var(--accent-glow) 0%, transparent 70%);
  pointer-events: none;
}

.subscribe-title {
  font-size: 2rem;
  font-weight: 700;
  margin-bottom: 1rem;
}

.subscribe-desc {
  color: var(--text-secondary);
  margin-bottom: 2rem;
}

.subscribe-form {
  max-width: 500px;
  margin: 0 auto;
}

.input-wrapper {
  display: flex;
  background: var(--bg-deep);
  border: 1px solid var(--border-subtle);
  border-radius: 50px;
  overflow: hidden;
  transition: var(--transition);
}

.input-wrapper:focus-within {
  border-color: var(--accent);
  box-shadow: 0 0 20px var(--accent-glow);
}

.input-wrapper input {
  flex: 1;
  background: transparent;
  border: none;
  color: var(--text-primary);
  padding: 16px 24px;
  font-size: 1rem;
  font-family: var(--font-sans);
  outline: none;
}

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

.btn-submit {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  background: var(--gradient-1);
  color: #000;
  font-weight: 600;
  border: none;
  padding: 16px 32px;
  cursor: pointer;
  font-size: 0.95rem;
  font-family: var(--font-sans);
  transition: var(--transition);
  white-space: nowrap;
}

.btn-submit:hover {
  filter: brightness(1.1);
}

/* ---------- Footer ---------- */
.footer {
  position: relative;
  z-index: 1;
  border-top: 1px solid var(--border-subtle);
  padding: 4rem 2rem 2rem;
  background: var(--bg-primary);
}

.footer-grid {
  max-width: 1280px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 2fr 1fr 1fr 1fr;
  gap: 4rem;
}

.footer-brand p {
  color: var(--text-secondary);
  margin-top: 1rem;
  font-size: 0.95rem;
}

.social-links {
  display: flex;
  gap: 1rem;
  margin-top: 1.5rem;
}

.social-link {
  width: 40px;
  height: 40px;
  border: 1px solid var(--border-subtle);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--text-secondary);
  transition: var(--transition);
}

.social-link:hover {
  color: var(--accent);
  border-color: var(--accent);
  box-shadow: 0 0 15px var(--accent-glow);
}

.footer-links h4 {
  font-size: 0.9rem;
  font-weight: 600;
  margin-bottom: 1rem;
  font-family: var(--font-mono);
  color: var(--accent);
}

.footer-links ul {
  display: flex;
  flex-direction: column;
  gap: 0.6rem;
}

.footer-links a {
  color: var(--text-secondary);
  font-size: 0.9rem;
  transition: var(--transition);
}

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

.footer-bottom {
  max-width: 1280px;
  margin: 0 auto;
  text-align: center;
  padding-top: 2rem;
  margin-top: 3rem;
}

.footer-line {
  height: 1px;
  background: var(--border-subtle);
  margin-bottom: 1.5rem;
}

.footer-bottom p {
  color: var(--text-muted);
  font-size: 0.85rem;
}

/* ---------- Reading Progress Bar ---------- */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 3px;
  background: var(--gradient-1);
  z-index: 10000;
  transition: width 0.1s linear;
  box-shadow: 0 0 10px var(--accent-glow);
}

/* ---------- Back to Top ---------- */
.back-to-top {
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 44px;
  height: 44px;
  border-radius: 50%;
  background: var(--bg-card);
  border: 1px solid var(--border-glow);
  color: var(--accent);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  z-index: 999;
  opacity: 0;
  transform: translateY(20px);
  pointer-events: none;
  transition: all var(--transition);
  box-shadow: 0 0 15px rgba(0,0,0,0.4);
}

.back-to-top.visible {
  opacity: 1;
  transform: translateY(0);
  pointer-events: all;
}

.back-to-top:hover {
  background: var(--accent);
  color: #000;
  box-shadow: 0 0 25px var(--accent-glow);
  transform: translateY(-3px);
}

/* ---------- Toast Notification ---------- */
.toast-container {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%);
  z-index: 10001;
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
  pointer-events: none;
}

.toast {
  background: var(--bg-card);
  border: 1px solid var(--accent);
  color: var(--text-primary);
  padding: 12px 24px;
  border-radius: 50px;
  font-size: 0.9rem;
  font-family: var(--font-mono);
  box-shadow: 0 0 25px var(--accent-glow);
  animation: toastIn 0.4s ease, toastOut 0.4s ease 2.2s forwards;
  pointer-events: all;
  white-space: nowrap;
}

.toast.success {
  border-color: #00e676;
  box-shadow: 0 0 25px rgba(0, 230, 118, 0.3);
}

.toast.error {
  border-color: #ff5252;
  box-shadow: 0 0 25px rgba(255, 82, 82, 0.3);
}

@keyframes toastIn {
  from { opacity: 0; transform: translateY(20px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes toastOut {
  from { opacity: 1; transform: translateY(0); }
  to { opacity: 0; transform: translateY(-20px); }
}

/* ---------- Animations ---------- */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(30px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.animate-in {
  animation: fadeInUp 0.6s ease forwards;
}

/* ---------- Responsive ---------- */
@media (max-width: 1024px) {
  .hero {
    flex-direction: column;
    text-align: center;
    padding: 100px 0 60px;
  }

  .hero-title {
    font-size: 2.5rem;
  }

  .hero-actions {
    justify-content: center;
  }

  .hero-stats {
    justify-content: center;
  }

  .hero-visual {
    height: 300px;
  }

  .featured-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .featured-main {
    grid-column: span 2;
    grid-template-columns: 1fr;
  }

  .featured-main .card-image {
    height: 250px;
    border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  }

  .featured-main .card-body {
    border-radius: 0 0 var(--radius-lg) var(--radius-lg);
  }

  .category-grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .footer-grid {
    grid-template-columns: 1fr 1fr;
  }
}

@media (max-width: 768px) {
  .nav-links {
    position: fixed;
    top: 0;
    right: -100%;
    width: 280px;
    height: 100vh;
    background: var(--bg-primary);
    flex-direction: column;
    padding: 100px 2rem 2rem;
    border-left: 1px solid var(--border-subtle);
    transition: right var(--transition);
    z-index: 999;
  }

  .nav-links.open {
    right: 0;
  }

  .hamburger {
    display: flex;
    z-index: 1000;
  }

  .hero-title {
    font-size: 2rem;
  }

  .featured-grid {
    grid-template-columns: 1fr;
  }

  .featured-main {
    grid-column: span 1;
  }

  .category-grid {
    grid-template-columns: 1fr;
  }

  .footer-grid {
    grid-template-columns: 1fr;
    gap: 2rem;
  }

  .hero-stats {
    gap: 1.5rem;
  }

  .stat-num {
    font-size: 1.5rem;
  }

  .section-title {
    font-size: 1.5rem;
  }

  .input-wrapper {
    flex-direction: column;
    border-radius: var(--radius);
    border: none;
    gap: 0.75rem;
    background: transparent;
  }

  .input-wrapper input {
    background: var(--bg-deep);
    border: 1px solid var(--border-subtle);
    border-radius: 50px;
  }

  .btn-submit {
    border-radius: 50px;
    justify-content: center;
  }
}

@media (max-width: 480px) {
  .hero-title {
    font-size: 1.6rem;
  }

  .hero-actions {
    flex-direction: column;
  }

  .hero-stats {
    gap: 1rem;
  }

  .stat-num {
    font-size: 1.3rem;
  }

  .blog-card .card-image {
    height: 180px;
  }
}