/* ============================================
   Simple3D – Pure HTML/CSS Design System
   ============================================ */

:root {
  --color-primary: #1e40af;
  --color-primary-hover: #1e3a8a;
  --color-primary-light: #bfdbfe;
  --color-cyan: #06b6d4;
  --color-violet: #8b5cf6;
  --color-amber: #f59e0b;
  --color-pink: #ec4899;
  --color-text: #0f172a;
  --color-text-muted: #334155;
  --color-bg: #ffffff;
  --color-bg-alt: #f1f5f9;
  --color-surface: rgba(255, 255, 255, 0.72);
  --color-surface-strong: rgba(255, 255, 255, 0.9);
  --color-border: #cbd5e1;
  --color-border-soft: rgba(100, 116, 139, 0.4);
  --shadow-sm: 0 2px 4px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 6px 12px -2px rgba(0, 0, 0, 0.15), 0 4px 6px -3px rgba(0, 0, 0, 0.12);
  --shadow-lg: 0 14px 24px -4px rgba(0, 0, 0, 0.18), 0 8px 12px -6px rgba(0, 0, 0, 0.14);
  --shadow-glow: 0 24px 56px rgba(30, 64, 175, 0.28), 0 12px 24px rgba(30, 64, 175, 0.18);
  --shadow-3d: 0 20px 60px rgba(0, 0, 0, 0.25), 0 8px 20px rgba(0, 0, 0, 0.15);
  --radius: 16px;
  --radius-sm: 10px;
  --radius-lg: 24px;
  --header-height: 80px;
  --max-width: 1400px;
  --transition: 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 0.5s cubic-bezier(0.4, 0, 0.2, 1);

  --gradient-primary: linear-gradient(135deg, #1e40af 0%, #06b6d4 40%, #8b5cf6 70%, #ec4899 100%);
  --gradient-soft: radial-gradient(1400px 800px at 5% 5%, rgba(30, 64, 175, 0.3), transparent 55%),
    radial-gradient(1000px 700px at 95% 15%, rgba(6, 182, 212, 0.25), transparent 50%),
    radial-gradient(900px 700px at 50% 95%, rgba(139, 92, 246, 0.22), transparent 50%),
    radial-gradient(800px 600px at 25% 50%, rgba(236, 72, 153, 0.18), transparent 50%);
}

@keyframes float {
  0%, 100% { transform: translateY(0px) translateZ(0); }
  50% { transform: translateY(-20px) translateZ(10px); }
}

@keyframes gradient-shift {
  0% { background-position: 0% 50%; }
  50% { background-position: 100% 50%; }
  100% { background-position: 0% 50%; }
}

@keyframes glow-pulse {
  0%, 100% { opacity: 0.6; filter: blur(20px); }
  50% { opacity: 1; filter: blur(30px); }
}

@keyframes rotate-3d {
  0% { transform: perspective(1000px) rotateY(0deg) translateZ(0); }
  100% { transform: perspective(1000px) rotateY(360deg) translateZ(0); }
}

@keyframes slide-up {
  from {
    opacity: 0;
    transform: translateY(40px) translateZ(0);
  }
  to {
    opacity: 1;
    transform: translateY(0) translateZ(0);
  }
}

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

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  font-size: 16px;
  line-height: 1.6;
  color: var(--color-text);
  background:
    linear-gradient(180deg, rgba(15, 23, 42, 0.75) 0%, rgba(15, 23, 42, 0.85) 100%),
    url('assets/background-3d.png');
  background-size: cover;
  background-position: center center;
  background-attachment: fixed;
  background-repeat: no-repeat;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  position: relative;
}

body::after {
  content: "";
  position: fixed;
  inset: 0;
  background: 
    radial-gradient(circle at 20% 30%, rgba(30, 64, 175, 0.15) 0%, transparent 50%),
    radial-gradient(circle at 80% 70%, rgba(6, 182, 212, 0.12) 0%, transparent 50%),
    radial-gradient(circle at 50% 50%, rgba(139, 92, 246, 0.1) 0%, transparent 60%);
  pointer-events: none;
  z-index: 0;
  animation: gradient-shift 20s ease infinite;
}

/* Subtle overlay for better text readability */
body::before {
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background: 
    linear-gradient(180deg, rgba(15, 23, 42, 0.4) 0%, rgba(15, 23, 42, 0.6) 100%),
    radial-gradient(circle at 50% 50%, transparent 0%, rgba(15, 23, 42, 0.3) 100%);
  z-index: 0;
  opacity: 0.7;
}

body > * {
  position: relative;
  z-index: 1;
}

/* Ensure main content has proper contrast */
.main {
  background: rgba(255, 255, 255, 0.02);
  backdrop-filter: blur(1px);
  -webkit-backdrop-filter: blur(1px);
}

/* 3D decorative elements */
.main::before {
  content: "";
  position: absolute;
  top: 10%;
  right: -5%;
  width: 400px;
  height: 400px;
  background: var(--gradient-primary);
  border-radius: 30% 70% 70% 30% / 30% 30% 70% 70%;
  opacity: 0.12;
  filter: blur(60px);
  transform: perspective(1000px) rotateZ(45deg) rotateY(20deg);
  pointer-events: none;
  z-index: 0;
  animation: float 12s ease-in-out infinite, rotate-3d 20s linear infinite;
}

.main::after {
  content: "";
  position: absolute;
  bottom: 15%;
  left: -8%;
  width: 500px;
  height: 500px;
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.2), rgba(6, 182, 212, 0.15), rgba(236, 72, 153, 0.12));
  border-radius: 60% 40% 30% 70% / 60% 30% 70% 40%;
  filter: blur(70px);
  transform: perspective(1200px) rotateZ(-30deg) rotateX(15deg);
  pointer-events: none;
  z-index: 0;
  animation: float 15s ease-in-out infinite reverse, glow-pulse 10s ease-in-out infinite;
}

.main > * {
  position: relative;
  z-index: 1;
}

/* ========== Header ========== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(24px) saturate(180%);
  -webkit-backdrop-filter: blur(24px) saturate(180%);
  border-bottom: 1px solid rgba(255, 255, 255, 0.15);
  box-shadow: 
    0 8px 32px rgba(0, 0, 0, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.1);
}

.header-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 1.5rem;
  height: var(--header-height);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.site-logo {
  font-weight: 700;
  font-size: 1.5rem;
  color: rgba(255, 255, 255, 0.95);
  text-decoration: none;
  letter-spacing: -0.02em;
  position: relative;
  transform: translateZ(0);
  transition: transform var(--transition-slow), color var(--transition);
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.3);
}

.site-logo:hover {
  color: rgba(255, 255, 255, 1);
  transform: translateY(-2px) translateZ(10px) scale(1.05);
}

.site-logo::after {
  content: "";
  display: inline-block;
  width: 14px;
  height: 14px;
  margin-left: 0.5rem;
  border-radius: 999px;
  background: var(--gradient-primary);
  box-shadow: 
    0 0 0 3px rgba(30, 64, 175, 0.18),
    0 6px 16px rgba(30, 64, 175, 0.32),
    0 2px 6px rgba(0, 0, 0, 0.2),
    inset 0 1px 3px rgba(255, 255, 255, 0.5),
    inset 0 -1px 2px rgba(0, 0, 0, 0.1);
  vertical-align: middle;
  transform: translateZ(0) perspective(200px) rotateX(15deg) rotateY(-10deg);
  position: relative;
  transition: transform var(--transition-slow), box-shadow var(--transition-slow);
}

.site-logo:hover::after {
  transform: translateZ(15px) perspective(200px) rotateX(10deg) rotateY(-5deg) scale(1.1);
  box-shadow: 
    0 0 0 4px rgba(30, 64, 175, 0.22),
    0 10px 24px rgba(30, 64, 175, 0.4),
    0 4px 10px rgba(0, 0, 0, 0.25),
    inset 0 1px 3px rgba(255, 255, 255, 0.6),
    inset 0 -1px 2px rgba(0, 0, 0, 0.15);
}

.nav-main {
  display: flex;
  align-items: center;
  gap: 0.25rem;
  flex-wrap: wrap;
}

.nav-main a {
  padding: 0.5rem 0.75rem;
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  font-weight: 600;
  border-radius: var(--radius-sm);
  transition: all var(--transition-slow);
  position: relative;
  transform: translateZ(0);
  background: rgba(255, 255, 255, 0.1);
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow: 
    0 2px 8px rgba(0, 0, 0, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.15);
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}

.nav-main a::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-sm);
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-slow);
  z-index: -1;
  filter: blur(6px);
}

.nav-main a:nth-child(1) { /* Guides */
  background: linear-gradient(135deg, rgba(6, 182, 212, 0.25), rgba(6, 182, 212, 0.15));
  border-color: rgba(6, 182, 212, 0.4);
  color: #06b6d4;
}

.nav-main a:nth-child(2) { /* Troubleshooting */
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.25), rgba(139, 92, 246, 0.15));
  border-color: rgba(139, 92, 246, 0.4);
  color: #8b5cf6;
}

.nav-main a:nth-child(3) { /* Tests */
  background: linear-gradient(135deg, rgba(245, 158, 11, 0.3), rgba(245, 158, 11, 0.2));
  border-color: rgba(245, 158, 11, 0.45);
  color: #f59e0b;
  box-shadow: 
    0 4px 12px rgba(245, 158, 11, 0.3),
    0 2px 8px rgba(0, 0, 0, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
}

.nav-main a:nth-child(4) { /* Empfehlungen */
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.25), rgba(30, 64, 175, 0.15));
  border-color: rgba(30, 64, 175, 0.4);
  color: #3b82f6;
}

.nav-main a:nth-child(5) { /* Über */
  background: linear-gradient(135deg, rgba(6, 182, 212, 0.22), rgba(139, 92, 246, 0.15));
  border-color: rgba(6, 182, 212, 0.35);
  color: #06b6d4;
}

.nav-main a:nth-child(6) { /* Kontakt */
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.22), rgba(245, 158, 11, 0.15));
  border-color: rgba(139, 92, 246, 0.35);
  color: #8b5cf6;
}

.nav-main a:hover {
  transform: translateY(-4px) translateZ(15px) scale(1.05);
  box-shadow: 
    0 12px 32px rgba(0, 0, 0, 0.2),
    0 6px 16px rgba(0, 0, 0, 0.15),
    inset 0 1px 0 rgba(255, 255, 255, 1);
  border-width: 2px;
}

.nav-main a:nth-child(1):hover {
  background: linear-gradient(135deg, rgba(8, 145, 178, 0.25), rgba(8, 145, 178, 0.15));
  border-color: #0891b2;
  box-shadow: 
    0 12px 32px rgba(8, 145, 178, 0.35),
    0 6px 16px rgba(8, 145, 178, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.nav-main a:nth-child(2):hover {
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.25), rgba(124, 58, 237, 0.15));
  border-color: #7c3aed;
  box-shadow: 
    0 12px 32px rgba(124, 58, 237, 0.35),
    0 6px 16px rgba(124, 58, 237, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.nav-main a:nth-child(3):hover {
  background: linear-gradient(135deg, rgba(217, 119, 6, 0.3), rgba(217, 119, 6, 0.2));
  border-color: #d97706;
  box-shadow: 
    0 16px 40px rgba(217, 119, 6, 0.4),
    0 8px 20px rgba(217, 119, 6, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 1);
  transform: translateY(-5px) translateZ(20px) scale(1.08);
}

.nav-main a:nth-child(4):hover {
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.25), rgba(30, 64, 175, 0.15));
  border-color: #1e40af;
  box-shadow: 
    0 12px 32px rgba(30, 64, 175, 0.35),
    0 6px 16px rgba(30, 64, 175, 0.25),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.nav-main a:nth-child(5):hover {
  background: linear-gradient(135deg, rgba(8, 145, 178, 0.22), rgba(124, 58, 237, 0.15));
  border-color: #0891b2;
  box-shadow: 
    0 12px 32px rgba(8, 145, 178, 0.3),
    0 6px 16px rgba(124, 58, 237, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.nav-main a:nth-child(6):hover {
  background: linear-gradient(135deg, rgba(124, 58, 237, 0.22), rgba(217, 119, 6, 0.15));
  border-color: #7c3aed;
  box-shadow: 
    0 12px 32px rgba(124, 58, 237, 0.3),
    0 6px 16px rgba(217, 119, 6, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.nav-main a:hover::before {
  opacity: 0.4;
}

.nav-main a.active {
  transform: translateY(-2px) translateZ(10px);
  box-shadow: 
    0 8px 24px rgba(0, 0, 0, 0.15),
    0 4px 12px rgba(0, 0, 0, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 1);
  border-width: 2px;
}

/* Mobile menu: details/summary, no JS */
.nav-details {
  display: flex;
  align-items: center;
}

.nav-toggle {
  display: none;
  list-style: none;
  cursor: pointer;
  padding: 0.5rem;
  font-size: 1.5rem;
  color: var(--color-text);
  border-radius: var(--radius-sm);
  transition: background var(--transition);
}

.nav-toggle:hover {
  background: rgba(15, 23, 42, 0.06);
}

.nav-toggle::-webkit-details-marker {
  display: none;
}

@media (min-width: 769px) {
  .nav-details[open] .nav-toggle {
    display: none;
  }
  .nav-main {
    display: flex;
  }
}

@media (max-width: 768px) {
  .nav-details {
    display: block;
  }

  .nav-toggle {
    display: block;
  }

  .nav-details:not([open]) .nav-main {
    display: none;
  }

  .nav-details[open] .nav-main {
    display: flex;
  }

  .nav-main {
    position: absolute;
    top: var(--header-height);
    left: 0;
    right: 0;
    background: rgba(255, 255, 255, 0.92);
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--color-border-soft);
    padding: 1rem;
    flex-direction: column;
    align-items: stretch;
    box-shadow: 0 18px 50px rgba(15, 23, 42, 0.12);
  }

  .nav-main a {
    padding: 0.75rem 1rem;
  }
}

/* ========== Main content ========== */
.main {
  flex: 1;
  width: 100%;
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 3rem 1.5rem 4rem;
}

.page-title {
  font-size: clamp(2rem, 5vw, 3rem);
  font-weight: 700;
  letter-spacing: -0.03em;
  color: rgba(255, 255, 255, 0.98);
  margin: 0 0 0.5rem;
  line-height: 1.2;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.5), 0 0 32px rgba(0, 0, 0, 0.35);
}

.page-lead {
  font-size: 1.125rem;
  color: rgba(255, 255, 255, 0.9);
  margin: 0 0 2.5rem;
  max-width: 60ch;
  text-shadow: 0 1px 6px rgba(0, 0, 0, 0.5);
}

/* ========== Hero (Startseite) ========== */
.hero {
  position: relative;
  text-align: center;
  padding: 4rem 0 1.5rem;
  margin: 0 -1.5rem 1rem;
  overflow: hidden;
  display: flex;
  align-items: center;
  justify-content: center;
}

.hero::before {
  content: "";
  position: absolute;
  inset: -200px -200px -200px -200px;
  background: transparent;
  filter: blur(20px);
  opacity: 0;
  transform: perspective(1200px) rotateX(3deg);
  animation: none;
  z-index: 0;
}

.hero::after {
  content: "";
  position: absolute;
  inset: 0;
  background: transparent;
  pointer-events: none;
}

.hero-inner {
  position: relative;
  max-width: 920px;
  margin: 0 auto;
  padding: 0 1.5rem;
  background: transparent;
  z-index: 1;
}

.hero-eyebrow {
  margin: 0 auto 1.25rem;
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.5rem 1.25rem;
  border-radius: 999px;
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border: none;
  box-shadow: none;
  font-weight: 700;
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.95);
  transform: translateZ(0);
  position: relative;
  animation: slide-up 0.6s cubic-bezier(0.4, 0, 0.2, 1) both;
  letter-spacing: 0.02em;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.6), 0 0 20px rgba(0, 0, 0, 0.4);
}

.gradient-text {
  background: var(--gradient-primary);
  background-size: 200% 200%;
  -webkit-background-clip: text;
  background-clip: text;
  color: transparent;
  animation: gradient-shift 5s ease infinite;
  display: inline-block;
  filter: drop-shadow(0 4px 12px rgba(30, 64, 175, 0.3));
}

.hero-title {
  font-size: clamp(3rem, 8vw, 5.5rem);
  font-weight: 900;
  letter-spacing: -0.05em;
  color: rgba(255, 255, 255, 0.98);
  margin: 0 0 1.5rem;
  line-height: 1.05;
  text-shadow: 
    0 4px 20px rgba(0, 0, 0, 0.5),
    0 8px 32px rgba(0, 0, 0, 0.4),
    0 0 40px rgba(30, 64, 175, 0.3);
  transform: perspective(800px) translateZ(30px);
  position: relative;
  animation: slide-up 0.8s cubic-bezier(0.4, 0, 0.2, 1);
}

.hero-lead {
  font-size: clamp(1.25rem, 2.5vw, 1.5rem);
  color: rgba(255, 255, 255, 0.9);
  max-width: 60ch;
  margin: 0 auto 2.5rem;
  font-weight: 500;
  line-height: 1.7;
  text-shadow: 0 2px 12px rgba(0, 0, 0, 0.4);
  animation: slide-up 0.8s cubic-bezier(0.4, 0, 0.2, 1) 0.1s both;
}

.hero-actions {
  display: flex;
  justify-content: center;
  gap: 1rem;
  flex-wrap: wrap;
  margin-bottom: 2rem;
  animation: slide-up 0.8s cubic-bezier(0.4, 0, 0.2, 1) 0.15s both;
}

.hero-badges {
  display: flex;
  justify-content: center;
  gap: 0.75rem;
  flex-wrap: wrap;
  animation: slide-up 0.8s cubic-bezier(0.4, 0, 0.2, 1) 0.2s both;
}

.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.5rem 1rem;
  border-radius: 999px;
  font-size: 0.9375rem;
  font-weight: 600;
  background: transparent;
  backdrop-filter: none;
  -webkit-backdrop-filter: none;
  border: none;
  color: rgba(255, 255, 255, 0.95);
  box-shadow: none;
  transform: translateZ(0);
  transition: all var(--transition-slow);
  animation: float 6s ease-in-out infinite;
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.6), 0 0 20px rgba(0, 0, 0, 0.4);
}

.badge:nth-child(1) { animation-delay: 0s; }
.badge:nth-child(2) { animation-delay: 1.5s; }
.badge:nth-child(3) { animation-delay: 3s; }
.badge:nth-child(4) { animation-delay: 4.5s; }

.badge:hover {
  transform: translateY(-4px) translateZ(10px) scale(1.05);
  box-shadow: 
    0 16px 40px rgba(15, 23, 42, 0.18),
    0 8px 20px rgba(30, 64, 175, 0.15),
    inset 0 1px 0 rgba(255, 255, 255, 1);
}

.badge-dot {
  width: 9px;
  height: 9px;
  border-radius: 999px;
  background: var(--gradient-primary);
  box-shadow: 
    0 0 0 2px rgba(30, 64, 175, 0.2),
    0 2px 6px rgba(30, 64, 175, 0.3),
    inset 0 1px 2px rgba(255, 255, 255, 0.4);
  transform: translateZ(0);
  position: relative;
}

/* ========== Cards ========== */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 2rem;
  animation: slide-up 0.8s cubic-bezier(0.4, 0, 0.2, 1) 0.2s both;
}

.card {
  position: relative;
  background: rgba(15, 23, 42, 0.6);
  backdrop-filter: blur(20px) saturate(180%);
  -webkit-backdrop-filter: blur(20px) saturate(180%);
  border: 1px solid rgba(255, 255, 255, 0.2);
  border-radius: var(--radius-lg);
  padding: 2rem;
  box-shadow: 
    0 20px 60px rgba(0, 0, 0, 0.4),
    0 8px 24px rgba(0, 0, 0, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.15),
    inset 0 -1px 0 rgba(0, 0, 0, 0.2);
  transition: all var(--transition-slow);
  text-decoration: none;
  color: inherit;
  display: block;
  transform-style: preserve-3d;
  transform: translateZ(0);
  animation: slide-up 0.6s cubic-bezier(0.4, 0, 0.2, 1) both;
}

.card:nth-child(1) { animation-delay: 0.1s; }
.card:nth-child(2) { animation-delay: 0.2s; }
.card:nth-child(3) { animation-delay: 0.3s; }
.card:nth-child(4) { animation-delay: 0.4s; }

.card::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  padding: 1px;
  background: var(--gradient-primary);
  opacity: 0.0;
  transition: opacity var(--transition-slow);
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
}

.card:hover {
  box-shadow: var(--shadow-glow);
  border-color: rgba(30, 64, 175, 0.28);
  transform: translateY(-10px) translateZ(20px) perspective(1000px) rotateX(4deg) rotateY(-3deg) scale(1.02);
}

.card::after {
  content: "";
  position: absolute;
  inset: -2px;
  border-radius: var(--radius);
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-slow);
  z-index: -1;
  filter: blur(8px);
  transform: translateZ(-10px);
}

.card:hover::before {
  opacity: 1;
}

.card[data-accent="cyan"]::before {
  background: linear-gradient(135deg, #1e40af 0%, #0891b2 70%);
}

.card[data-accent="cyan"]::after {
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.4) 0%, rgba(8, 145, 178, 0.35) 70%);
}

.card[data-accent="violet"]::before {
  background: linear-gradient(135deg, #1e40af 0%, #7c3aed 75%);
}

.card[data-accent="violet"]::after {
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.4) 0%, rgba(124, 58, 237, 0.35) 75%);
}

.card[data-accent="amber"]::before {
  background: linear-gradient(135deg, #1e40af 0%, #d97706 85%);
}

.card[data-accent="amber"]::after {
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.4) 0%, rgba(217, 119, 6, 0.35) 85%);
}

.card:hover::after {
  opacity: 0.6;
}

.card-title {
  font-size: 1.5rem;
  font-weight: 700;
  margin: 0 0 0.75rem;
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.4);
  transform: translateZ(10px);
  position: relative;
  letter-spacing: -0.02em;
  line-height: 1.3;
}

.card-desc {
  font-size: 0.9375rem;
  color: rgba(255, 255, 255, 0.8);
  margin: 0;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.3);
}

.card-meta {
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.7);
  margin-top: 1rem;
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.3);
}

/* ========== Section blocks ========== */
.section {
  margin-bottom: 3rem;
}

.section-title {
  font-size: 1rem;
  font-weight: 400;
  margin: 0 0 1.5rem;
  color: rgba(255, 255, 255, 0.9);
  position: relative;
  transform: translateZ(0);
  letter-spacing: 0.02em;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.4);
  animation: slide-up 0.6s cubic-bezier(0.4, 0, 0.2, 1) both;
}

.section-title::after {
  content: "";
  display: block;
  width: 64px;
  height: 4px;
  margin-top: 0.6rem;
  border-radius: 999px;
  background: var(--gradient-primary);
  opacity: 0.85;
  box-shadow: 
    0 2px 8px rgba(30, 64, 175, 0.3),
    0 0 12px rgba(30, 64, 175, 0.2);
  transform: perspective(200px) rotateX(5deg) translateZ(5px);
}

/* ========== Content typography ========== */
.content h2 {
  font-size: 1.5rem;
  font-weight: 600;
  margin: 2rem 0 0.75rem;
  color: rgba(255, 255, 255, 0.98);
  text-shadow: 0 2px 8px rgba(0, 0, 0, 0.5), 0 0 24px rgba(0, 0, 0, 0.3);
}

.content h3 {
  font-size: 1.25rem;
  font-weight: 600;
  margin: 1.5rem 0 0.5rem;
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 2px 6px rgba(0, 0, 0, 0.5);
}

.content p {
  margin: 0 0 1rem;
  color: rgba(255, 255, 255, 0.92);
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.5);
  line-height: 1.7;
}

.content ul, .content ol {
  margin: 0 0 1rem;
  padding-left: 1.5rem;
  color: rgba(255, 255, 255, 0.92);
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.5);
}

.content li {
  margin-bottom: 0.35rem;
}

.content a {
  color: #93c5fd;
  text-decoration: none;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
}

.content a:hover {
  text-decoration: underline;
}

.content code {
  font-size: 0.9em;
  padding: 0.15em 0.4em;
  background: rgba(255, 255, 255, 0.15);
  color: rgba(255, 255, 255, 0.95);
  border-radius: 4px;
  border: 1px solid rgba(255, 255, 255, 0.25);
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.4);
}

/* ========== Buttons ========== */
.btn {
  display: inline-block;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 500;
  text-align: center;
  text-decoration: none;
  border-radius: var(--radius-sm);
  border: none;
  cursor: pointer;
  transition: background var(--transition), color var(--transition), transform var(--transition-slow), box-shadow var(--transition-slow);
}

.btn-primary {
  background: var(--gradient-primary);
  color: white;
  box-shadow: 
    0 20px 48px rgba(30, 64, 175, 0.4),
    0 10px 24px rgba(30, 64, 175, 0.3),
    0 4px 12px rgba(0, 0, 0, 0.2),
    inset 0 1px 0 rgba(255, 255, 255, 0.3),
    inset 0 -2px 4px rgba(0, 0, 0, 0.15);
  text-shadow: 
    0 1px 3px rgba(0, 0, 0, 0.2),
    0 0 8px rgba(255, 255, 255, 0.3);
  transform: translateZ(0) perspective(400px) rotateX(2deg);
  position: relative;
  border: 1px solid rgba(255, 255, 255, 0.2);
}

.btn-primary::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-sm);
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.3), rgba(255, 255, 255, 0.1));
  opacity: 0.6;
  transition: opacity var(--transition);
  z-index: 0;
}

.btn-primary::after {
  content: "";
  position: absolute;
  inset: -4px;
  border-radius: var(--radius-sm);
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-slow);
  z-index: -1;
  filter: blur(12px);
  transform: translateZ(-10px);
}

.btn-primary > * {
  position: relative;
  z-index: 1;
}

.btn-primary:hover {
  background: linear-gradient(135deg, #1e3a8a 0%, #0891b2 45%, #6d28d9 100%);
  color: white;
  transform: translateY(-6px) translateZ(20px) scale(1.05) perspective(500px) rotateX(-3deg);
  box-shadow: 
    0 32px 72px rgba(30, 64, 175, 0.5),
    0 16px 36px rgba(30, 64, 175, 0.4),
    0 8px 16px rgba(0, 0, 0, 0.25),
    inset 0 2px 4px rgba(255, 255, 255, 0.4),
    inset 0 -3px 6px rgba(0, 0, 0, 0.2);
  border-color: rgba(255, 255, 255, 0.3);
}

.btn-primary:hover::before {
  opacity: 0.8;
}

.btn-primary:hover::after {
  opacity: 0.7;
}

.btn-outline {
  background: linear-gradient(135deg, rgba(255, 255, 255, 0.85), rgba(255, 255, 255, 0.75));
  color: var(--color-text);
  border: 2px solid rgba(30, 64, 175, 0.3);
  box-shadow: 
    0 12px 32px rgba(15, 23, 42, 0.15),
    0 4px 12px rgba(0, 0, 0, 0.1),
    inset 0 1px 0 rgba(255, 255, 255, 1),
    inset 0 -1px 2px rgba(0, 0, 0, 0.05);
  transform: translateZ(0) perspective(400px) rotateX(1deg);
  position: relative;
}

.btn-outline::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius-sm);
  background: var(--gradient-primary);
  opacity: 0;
  transition: opacity var(--transition-slow);
  z-index: -1;
  filter: blur(8px);
}

.btn-outline:hover {
  background: linear-gradient(135deg, rgba(255, 255, 255, 1), rgba(255, 255, 255, 0.95));
  transform: translateY(-5px) translateZ(15px) scale(1.03) perspective(500px) rotateX(-2deg);
  box-shadow: 
    0 24px 56px rgba(15, 23, 42, 0.22),
    0 12px 28px rgba(0, 0, 0, 0.15),
    0 4px 12px rgba(30, 64, 175, 0.2),
    inset 0 2px 4px rgba(255, 255, 255, 1),
    inset 0 -2px 4px rgba(0, 0, 0, 0.08);
  border-color: rgba(30, 64, 175, 0.4);
  border-width: 2px;
}

.btn-outline:hover::before {
  opacity: 0.3;
}

/* ========== Ad placeholder ========== */
.ad-placeholder {
  position: relative;
  background: rgba(255, 255, 255, 0.65);
  border: 1px dashed var(--color-border-soft);
  border-radius: var(--radius);
  padding: 2rem;
  text-align: center;
  color: var(--color-text-muted);
  font-size: 0.875rem;
  margin: 2rem 0;
}

.ad-placeholder::before {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: var(--radius);
  padding: 1px;
  background: var(--gradient-primary);
  opacity: 0.3;
  -webkit-mask: linear-gradient(#000 0 0) content-box, linear-gradient(#000 0 0);
  -webkit-mask-composite: xor;
  mask-composite: exclude;
  pointer-events: none;
  box-shadow: 0 0 20px rgba(30, 64, 175, 0.2);
}

.ad-placeholder {
  transform: translateZ(0);
  position: relative;
}

.ad-placeholder::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%) perspective(400px) rotateX(5deg);
  width: 80%;
  height: 60%;
  border-radius: var(--radius);
  background: linear-gradient(135deg, rgba(30, 64, 175, 0.08), rgba(124, 58, 237, 0.06));
  pointer-events: none;
  z-index: -1;
}

/* ========== Form ========== */
.form-group {
  margin-bottom: 1.25rem;
}

.form-group label {
  display: block;
  font-weight: 500;
  margin-bottom: 0.375rem;
  color: var(--color-text);
}

.form-group input,
.form-group textarea {
  width: 100%;
  max-width: 400px;
  padding: 0.75rem 1rem;
  font-size: 1rem;
  font-family: inherit;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  background: var(--color-bg);
  color: var(--color-text);
  transition: border-color var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--color-primary);
  box-shadow: 0 0 0 3px var(--color-primary-light);
}

.form-group textarea {
  min-height: 140px;
  resize: vertical;
}

/* ========== Footer ========== */
.site-footer {
  background: rgba(15, 23, 42, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  margin-top: auto;
  box-shadow: 0 -8px 32px rgba(0, 0, 0, 0.3);
}

.footer-inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 2.5rem 1.5rem;
}

.footer-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 2rem;
  margin-bottom: 2rem;
}

.footer-col h4 {
  font-size: 0.875rem;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  color: rgba(255, 255, 255, 0.7);
  margin: 0 0 0.75rem;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.4);
}

.footer-col a {
  display: block;
  color: rgba(255, 255, 255, 0.9);
  text-decoration: none;
  font-size: 0.9375rem;
  padding: 0.25rem 0;
  transition: color var(--transition);
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.4);
}

.footer-col a:hover {
  color: #93c5fd;
}

.footer-bottom {
  padding-top: 1.5rem;
  border-top: 1px solid rgba(255, 255, 255, 0.15);
  font-size: 0.875rem;
  color: rgba(255, 255, 255, 0.75);
  text-shadow: 0 1px 3px rgba(0, 0, 0, 0.4);
}

.footer-bottom a {
  color: rgba(255, 255, 255, 0.75);
  text-decoration: none;
}

.footer-bottom a:hover {
  color: #93c5fd;
}

/* ========== List pages (guides, troubleshooting, etc.) ========== */
.article-list {
  list-style: none;
  padding: 0;
  margin: 0;
}

.article-list li {
  margin-bottom: 1rem;
}

.article-list a {
  display: block;
  padding: 1rem 1.25rem;
  background: rgba(255, 255, 255, 0.72);
  border: 1px solid var(--color-border-soft);
  border-radius: var(--radius);
  text-decoration: none;
  color: var(--color-text);
  font-weight: 500;
  transition: box-shadow var(--transition-slow), border-color var(--transition), transform var(--transition-slow);
  position: relative;
  overflow: hidden;
}

.article-list a::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 5px;
  background: var(--gradient-primary);
  opacity: 0.75;
  box-shadow: 
    0 0 8px rgba(30, 64, 175, 0.4),
    2px 0 12px rgba(30, 64, 175, 0.2);
  transform: translateZ(5px);
}

.article-list a:hover {
  box-shadow: 
    0 20px 48px rgba(15, 23, 42, 0.16),
    0 8px 20px rgba(0, 0, 0, 0.12),
    inset 0 1px 0 rgba(255, 255, 255, 0.9);
  border-color: rgba(30, 64, 175, 0.28);
  transform: translateY(-4px) translateX(4px) translateZ(10px);
}

.article-list a:hover::before {
  width: 6px;
  opacity: 1;
  box-shadow: 
    0 0 12px rgba(30, 64, 175, 0.5),
    3px 0 16px rgba(30, 64, 175, 0.3);
}

/* ========== Utility ========== */
.text-center { text-align: center; }
.mt-0 { margin-top: 0; }
.mb-2 { margin-bottom: 2rem; }

/* 3D cube icon for cards (optional decorative element) */
.card-icon-3d {
  display: inline-block;
  width: 24px;
  height: 24px;
  margin-bottom: 0.5rem;
  position: relative;
  transform-style: preserve-3d;
  transform: perspective(200px) rotateX(20deg) rotateY(-20deg);
}

.card-icon-3d::before,
.card-icon-3d::after {
  content: "";
  position: absolute;
  width: 24px;
  height: 24px;
  background: var(--gradient-primary);
  border-radius: 4px;
  box-shadow: 
    0 4px 12px rgba(30, 64, 175, 0.3),
    inset 0 1px 2px rgba(255, 255, 255, 0.3);
}

.card-icon-3d::before {
  transform: translateZ(12px);
  opacity: 0.9;
}

.card-icon-3d::after {
  transform: rotateY(90deg) translateZ(12px);
  opacity: 0.7;
}

@media (prefers-reduced-motion: reduce) {
  * {
    scroll-behavior: auto !important;
    transition: none !important;
    animation: none !important;
  }
  .card:hover,
  .article-list a:hover,
  .btn-primary:hover,
  .btn-outline:hover,
  .nav-main a:hover,
  .site-logo:hover,
  .badge:hover {
    transform: none !important;
  }
}