/* Kryentech - Japanisch MP3 Generator */
:root {
  --bg: #f3f4f8;
  --bg-card: #ffffff;
  --bg-surface: #f8f8fb;
  --bg-alt: #f5f6fa;
  --bg-highlight: #eef8f2;
  --text: #1f2430;
  --text-muted: #5f6675;
  --accent: #59b97c;
  --accent-hover: #4fab70;
  --success: #59b97c;
  --warning: #d29922;
  --danger: #f85149;
  --border: #e3e7ef;
  --radius-lg: 22px;
  --radius-md: 16px;
  --shadow-soft: 0 8px 25px rgba(0, 0, 0, 0.06);
  --shadow-soft-hover: 0 12px 30px rgba(0, 0, 0, 0.1);
  --font-sans: "DM Sans", "Segoe UI", system-ui, sans-serif;
  --font-mono: "JetBrains Mono", "Fira Code", monospace;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: var(--font-sans);
  background: var(--bg);
  color: var(--text);
  line-height: 1.6;
  min-height: 100vh;
}

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

header {
  background: rgba(255, 255, 255, 0.88);
  border-bottom: 1px solid var(--border);
  padding: 1rem 2rem;
  backdrop-filter: blur(6px);
}

.header-content {
  max-width: 1200px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 1rem;
}

header h1 {
  margin: 0;
  font-size: 1.75rem;
  font-weight: 700;
  letter-spacing: -0.03em;
  background: linear-gradient(135deg, #58a6ff 0%, #79b8ff 50%, #a5d0ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  position: relative;
  display: inline-block;
  text-shadow: 0 0 30px rgba(88, 166, 255, 0.3);
  transition: transform 0.3s ease, filter 0.3s ease;
}

.logo-image {
  height: 3.5rem;
  width: auto;
  display: block;
  filter: drop-shadow(0 0 8px rgba(88, 166, 255, 0.3));
  transition: transform 0.3s ease, filter 0.3s ease;
}

header h1:hover .logo-image {
  transform: scale(1.05);
  filter: drop-shadow(0 0 12px rgba(88, 166, 255, 0.5));
}

header h1:hover {
  transform: scale(1.02);
  filter: brightness(1.1);
}

header h1::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(135deg, #58a6ff 0%, #79b8ff 50%, #a5d0ff 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
  opacity: 0;
  filter: blur(10px);
  transition: opacity 0.3s ease;
  z-index: -1;
}

header h1:hover::before {
  opacity: 0.5;
}

nav {
  width: 100%;
  display: flex;
  justify-content: center;
}

nav ul {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  gap: 1.5rem;
  justify-content: center;
}

nav a {
  color: var(--text-muted);
  transition: color 0.2s ease;
  font-weight: 600;
}
nav a:hover, nav a.active {
  color: var(--accent);
  text-decoration: none;
}

/* Artikel-Inhaltsverzeichnis: globales nav ist flex — hier volle Breite untereinander */
nav.article-toc {
  display: block;
  width: 100%;
  margin: 1.5rem 0 1.75rem;
  padding: 1rem 1.25rem;
  background: var(--bg-highlight, rgba(0, 0, 0, 0.04));
  border-radius: 10px;
  border: 1px solid var(--border);
  box-sizing: border-box;
}

nav.article-toc h3 {
  margin: 0 0 0.85rem 0;
  font-size: 1.1rem;
}

nav.article-toc ol {
  margin: 0;
  padding-left: 1.35rem;
  line-height: 1.65;
  font-size: 0.95rem;
}

nav.article-toc li {
  margin: 0.25rem 0;
}

nav.article-toc a {
  font-weight: 600;
}

nav.article-toc a:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
  border-radius: 2px;
}

/* Anker-Sprünge: Überschrift nicht am oberen Rand kleben */
article.project-card [id^="iv-"],
#toc-heading {
  scroll-margin-top: 1.25rem;
}

p.article-back-toc {
  margin: 2rem 0 0;
  padding-top: 1.25rem;
  border-top: 1px solid var(--border);
  font-size: 0.92rem;
  text-align: center;
  color: var(--text-muted);
}

p.article-back-toc a {
  font-weight: 600;
}

main {
  max-width: 1160px;
  margin: 1.2rem auto 2rem;
  padding: 2rem;
  background: var(--bg-surface);
  border: 1px solid var(--border);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-soft);
}

/* Hero & CTA */
.hero {
  margin-bottom: 2.5rem;
}

.hero-title {
  font-size: 1.75rem;
  font-weight: 700;
  margin: 0 0 1rem 0;
  line-height: 1.3;
}

.hero-subtitle {
  font-size: 1.1rem;
  color: var(--text-muted);
  margin: 0 0 1.5rem 0;
}

.hero-simple {
  background: linear-gradient(145deg, rgba(88, 166, 255, 0.13), rgba(63, 185, 80, 0.1));
  border: 1px solid var(--border);
  border-radius: 16px;
  padding: 2.25rem;
  text-align: center;
}

.hero-simple .hero-title {
  margin-bottom: 0.9rem;
}

.hero-simple .hero-subtitle {
  max-width: 760px;
  margin: 0 auto 1.5rem;
}

/* Hero mit Bildern */
.hero-with-images {
  position: relative;
  min-height: 550px;
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 2.5rem;
  box-shadow: var(--shadow-soft);
}

.hero-carousel {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  z-index: 0;
}

.hero-slide {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  opacity: 0;
  transition: opacity 1.5s ease-in-out;
}

.hero-slide.active {
  opacity: 1;
  z-index: 1;
}

.hero-slide img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
}

.hero-overlay {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  bottom: 0;
  background: linear-gradient(
    135deg,
    rgba(10, 17, 32, 0.64) 0%,
    rgba(10, 17, 32, 0.42) 50%,
    rgba(10, 17, 32, 0.62) 100%
  );
  z-index: 2;
}

.hero-content {
  position: relative;
  z-index: 3;
  text-align: center;
  max-width: 800px;
  margin: 0 auto;
  padding: 3rem 2rem;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  min-height: 550px;
}

.hero-with-images .hero-title {
  color: #ffffff;
  text-shadow: 0 3px 14px rgba(0, 0, 0, 0.72);
  font-size: 2.2rem;
  font-weight: 800;
  margin-bottom: 1.25rem;
  max-width: 900px;
}

.hero-with-images .hero-subtitle {
  color: rgba(255, 255, 255, 0.95);
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.64);
  font-size: 1.2rem;
  margin-bottom: 1.25rem;
  max-width: 760px;
}

.hero-kicker {
  margin: 0 0 0.9rem;
  padding: 0.3rem 0.8rem;
  border-radius: 999px;
  background: rgba(89, 185, 124, 0.22);
  border: 1px solid rgba(255, 255, 255, 0.36);
  color: #ffffff;
  font-size: 0.88rem;
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.hero-personal {
  color: rgba(230, 237, 243, 0.8);
  font-size: 0.95rem;
  font-style: italic;
  margin: 0.5rem 0 2rem 0;
  text-shadow: 0 1px 4px rgba(0, 0, 0, 0.5);
}

.hero-indicators {
  position: absolute;
  bottom: 1.5rem;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  gap: 0.75rem;
  z-index: 4;
}

.hero-indicators .indicator {
  width: 10px;
  height: 10px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.4);
  cursor: pointer;
  transition: all 0.3s ease;
  border: 2px solid transparent;
}

.hero-indicators .indicator:hover {
  background: rgba(255, 255, 255, 0.6);
  transform: scale(1.2);
}

.hero-indicators .indicator.active {
  background: var(--accent);
  border-color: rgba(255, 255, 255, 0.3);
  width: 12px;
  height: 12px;
  box-shadow: 0 0 12px rgba(88, 166, 255, 0.6);
}

.cta-primary {
  display: inline-block;
  padding: 1rem 2rem;
  font-size: 1.15rem;
  font-weight: 600;
  background: var(--success);
  color: #ffffff;
  border-radius: 12px;
  text-decoration: none;
  transition: filter 0.2s, transform 0.15s;
}

.cta-hero {
  font-size: 1.18rem;
  padding: 1rem 2.5rem;
  box-shadow: 0 12px 28px rgba(13, 30, 20, 0.4);
}

.cta-primary:hover {
  background: var(--accent-hover);
  filter: brightness(1.01);
  transform: translateY(-2px);
  text-decoration: none;
}

/* Demo */
.demo-section {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  margin-bottom: 1.5rem;
}

.demo-section h3 {
  margin: 0 0 1rem 0;
  font-size: 1.2rem;
}

.demo-audio {
  width: 100%;
  max-width: 400px;
  margin: 0 0 1rem 0;
  display: block;
}

.cta-secondary {
  display: inline-block;
  color: #2f6a52;
  font-weight: 600;
}

.cta-secondary:hover {
  text-decoration: underline;
}

/* Price teaser */
.price-teaser {
  margin-bottom: 1rem;
  padding: 0.75rem 1rem;
  background: rgba(63, 185, 80, 0.1);
  border-radius: 8px;
  text-align: center;
}

.price-teaser p {
  margin: 0;
  font-size: 0.95rem;
}

/* Social proof */
.social-proof {
  margin-bottom: 1rem;
  text-align: center;
}

.social-proof p {
  margin: 0;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Trust badge */
.trust-badge {
  margin: 0 0 2rem 0;
  text-align: center;
  font-size: 0.9rem;
  color: var(--text-muted);
}

/* Section title */
.section-title {
  font-size: 1.25rem;
  margin: 0 0 1rem 0;
}

.feature-section {
  margin-bottom: 2.5rem;
  padding: 1.25rem;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
}

.feature-section h2 {
  margin: 0 0 1rem;
}

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

.feature-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.2rem;
  box-shadow: var(--shadow-soft);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.feature-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-soft-hover);
}

.feature-card h3 {
  margin: 0 0 0.6rem;
  font-size: 1.1rem;
}

.feature-card p {
  margin: 0;
  color: var(--text-muted);
}

/* SEO & About */
.seo-section, .about-section {
  margin-top: 2rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.seo-section h3, .about-section h3 {
  color: var(--text);
  margin: 0 0 0.75rem 0;
}

.about-section h2,
.faq-section h2,
.article-preview-section h2,
.contact-section h2 {
  color: var(--text);
  margin: 0 0 0.75rem;
}

.article-preview-section,
.faq-section,
.contact-section {
  margin-top: 2.4rem;
}

.audio-library-section {
  margin-top: 2rem;
}

.highlight-section {
  background: linear-gradient(180deg, var(--bg-highlight) 0%, #e9f4ee 100%);
  border: 1px solid #cfe6d8;
  border-radius: var(--radius-md);
  padding: 2rem;
  margin-top: 2.6rem;
  box-shadow: var(--shadow-soft);
}

.section-badge {
  display: inline-block;
  margin: 0 0 0.7rem;
  padding: 0.25rem 0.65rem;
  background: #e4f5ea;
  color: #2f6a52;
  border-radius: 999px;
  font-size: 0.78rem;
  font-weight: 700;
  letter-spacing: 0.05em;
}

.audio-library-section h2 {
  color: var(--text);
  margin: 0 0 0.75rem;
  line-height: 1.3;
  max-width: 52rem;
}

.audio-library-intro {
  color: var(--text-muted);
  margin: 0 0 1rem;
  max-width: 880px;
}

.audio-library-cta {
  display: flex;
  flex-wrap: wrap;
  gap: 0.75rem;
  margin: 0 0 0.5rem;
}

.cta-highlight {
  box-shadow: 0 12px 26px rgba(36, 94, 66, 0.26);
}

.audio-actions {
  display: flex;
  flex-wrap: wrap;
  gap: 0.8rem;
  margin: 0.4rem 0 0.8rem;
}

.audio-actions a {
  font-size: 0.92rem;
}

.audio-card details {
  margin-top: 0.25rem;
}

.audio-card summary {
  cursor: pointer;
  color: var(--text);
  font-weight: 600;
}

.vocab-preview {
  margin: 0.5rem 0 0;
  padding-left: 1.1rem;
  color: var(--text-muted);
}

.vocab-preview li {
  margin: 0.25rem 0;
}

.vocab-preview--elektro {
  list-style: none;
  padding-left: 0;
}

.vocab-preview--elektro > li {
  margin: 0.85rem 0;
  padding-bottom: 0.65rem;
  border-bottom: 1px solid var(--border);
}

.vocab-preview--elektro > li:last-child {
  border-bottom: none;
}

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

.elektro-example {
  margin: 0.35rem 0 0 0.5rem;
  font-size: 0.92rem;
  font-style: italic;
  color: var(--text-muted);
}

.elektro-report-meta {
  margin: 0.5rem 0 0.75rem;
  font-size: 0.92rem;
  color: var(--text-muted);
}

.article-preview-intro {
  color: var(--text-muted);
  margin: 0 0 1rem;
  max-width: 760px;
}

.contact-section p {
  color: var(--text-muted);
  margin-bottom: 0.75rem;
}

.project-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1.5rem;
  margin-top: 2rem;
}

.project-card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  box-shadow: var(--shadow-soft);
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.project-card:hover {
  transform: translateY(-5px);
  box-shadow: var(--shadow-soft-hover);
}

.project-card h3 {
  margin: 0 0 1rem 0;
  font-size: 1.2rem;
}

.project-card h4 {
  margin: 0 0 0.85rem 0;
  font-size: 1.05rem;
}

.project-card nav.article-toc h3 {
  margin: 0 0 0.85rem 0;
  font-size: 1.1rem;
}

.project-card p {
  margin: 0 0 0.75rem 0;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.project-card audio {
  width: 100%;
  margin: 0.5rem 0;
}

.project-link {
  display: inline-block;
  margin-top: 0.8rem;
  font-weight: 700;
}

.benefit-list {
  margin: 0.4rem 0 0.2rem 1.1rem;
  padding: 0;
  color: var(--text);
}

.benefit-list li {
  margin: 0.3rem 0;
  font-size: 0.92rem;
  line-height: 1.45;
}

.trust-section {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.4rem;
  box-shadow: var(--shadow-soft);
}

.trust-section p {
  color: var(--text-muted);
}

.trust-points {
  margin-top: 1rem;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem;
}

.trust-point {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.9rem;
}

.trust-point h3 {
  margin: 0 0 0.4rem;
  font-size: 1rem;
}

.trust-point p {
  margin: 0;
  font-size: 0.93rem;
}

#produkte {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
}

.article-preview-section {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
}

.faq-section {
  background: var(--bg-alt);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
}

.contact-section {
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.35rem;
}

h2, h3 {
  font-weight: 750;
}

@media (max-width: 900px) {
  main {
    margin: 0.6rem 0.75rem 1.25rem;
    padding: 1.25rem;
    border-radius: 18px;
  }

  .project-cards {
    grid-template-columns: 1fr;
  }

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

  .trust-points {
    grid-template-columns: 1fr;
  }
  
  .hero-with-images {
    min-height: 450px;
  }
  
  .hero-content {
    padding: 2rem 1.5rem;
    min-height: 450px;
  }
  
  .hero-with-images .hero-title {
    font-size: 1.6rem;
  }
  
  .hero-with-images .hero-subtitle {
    font-size: 1rem;
  }

  .cta-primary {
    width: 100%;
    text-align: center;
  }
  
  .hero-personal {
    font-size: 0.85rem;
  }
}

.card {
  background: var(--bg-card);
  border: 1px solid var(--border);
  border-radius: var(--radius-md);
  padding: 1.5rem;
  margin-bottom: 1.5rem;
  box-shadow: var(--shadow-soft);
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.75rem 1.5rem;
  font-size: 1rem;
  font-weight: 600;
  border: none;
  border-radius: 8px;
  cursor: pointer;
  transition: background 0.2s, color 0.2s;
}

.btn-primary {
  background: var(--accent);
  color: #fff;
}
.btn-primary:hover {
  background: var(--accent-hover);
}

.btn-secondary {
  background: var(--border);
  color: var(--text);
}
.btn-secondary:hover {
  background: #404852;
}

input, textarea, select {
  width: 100%;
  padding: 0.75rem;
  font-size: 1rem;
  font-family: inherit;
  background: #ffffff;
  border: 1px solid var(--border);
  border-radius: 8px;
  color: var(--text);
}

textarea {
  min-height: 120px;
  resize: vertical;
}

label {
  display: block;
  margin-bottom: 0.25rem;
  font-weight: 500;
  color: var(--text-muted);
}

.form-group {
  margin-bottom: 1rem;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1rem;
}

footer {
  text-align: center;
  padding: 2rem;
  color: var(--text-muted);
  font-size: 0.9rem;
}

/* Generator spezifisch */
.generator-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 1.5rem;
}

@media (max-width: 768px) {
  .generator-layout {
    grid-template-columns: 1fr;
  }
  .form-row {
    grid-template-columns: 1fr;
  }
}

.stats {
  display: flex;
  gap: 1rem;
  margin-bottom: 1rem;
  font-size: 0.9rem;
  color: var(--text-muted);
}

.badge {
  display: inline-block;
  padding: 0.25rem 0.5rem;
  border-radius: 6px;
  font-size: 0.8rem;
  font-weight: 600;
}

.badge-success { background: rgba(63,185,80,0.2); color: var(--success); }
.badge-warning { background: rgba(210,153,34,0.2); color: var(--warning); }
.badge-danger { background: rgba(248,81,73,0.2); color: var(--danger); }

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

.pricing-card {
  border: 2px solid var(--border);
  border-radius: 12px;
  padding: 1.5rem;
  text-align: center;
  transition: border-color 0.2s;
}
.pricing-card:hover, .pricing-card.featured {
  border-color: var(--accent);
}

.pricing-card h3 { margin: 0 0 0.5rem 0; }
.pricing-card .price { font-size: 1.75rem; font-weight: 700; color: var(--accent); }
.pricing-card .jobs { color: var(--text-muted); font-size: 0.9rem; }

/* LingAudia Highlight */
.lingaudia-highlight {
  background: linear-gradient(135deg, rgba(99, 102, 241, 0.12) 0%, rgba(20, 184, 166, 0.12) 100%);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: 16px;
  padding: 2.5rem;
  margin: 2rem auto;
  max-width: 800px;
  text-align: center;
  position: relative;
}

.sf-highlight-badge {
  display: inline-block;
  background: linear-gradient(135deg, #6366f1, #14b8a6);
  color: #fff;
  font-size: 0.75rem;
  font-weight: 700;
  padding: 0.3rem 0.8rem;
  border-radius: 20px;
  letter-spacing: 0.1em;
  margin-bottom: 1rem;
}

.sf-highlight-content h3 {
  font-size: 1.5rem;
  margin: 0 0 1rem;
  color: var(--text);
}

.sf-highlight-content p {
  color: var(--text-muted);
  line-height: 1.7;
  max-width: 650px;
  margin: 0 auto;
}

.sf-highlight-langs {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 0.5rem;
  margin-top: 1.25rem;
}

.sf-highlight-langs span {
  background: rgba(99, 102, 241, 0.15);
  color: var(--text);
  padding: 0.3rem 0.7rem;
  border-radius: 8px;
  font-size: 0.8rem;
  white-space: nowrap;
}

@media (max-width: 600px) {
  .lingaudia-highlight { padding: 1.5rem; }
  .sf-highlight-content h3 { font-size: 1.2rem; }
}

/* FAQ */
.faq-section details {
  margin-bottom: 0.75rem;
  border: 1px solid var(--border);
  border-radius: 12px;
  padding: 0.75rem 1rem;
  background: #ffffff;
  box-shadow: 0 3px 10px rgba(25, 38, 69, 0.05);
}

.faq-section summary {
  cursor: pointer;
  font-weight: 600;
}

.faq-section details[open] summary {
  margin-bottom: 0.5rem;
}

/* Cookie-Hinweis */
.cookie-banner {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  background: #ffffff;
  border-top: 1px solid var(--border);
  padding: 1rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1rem;
  flex-wrap: wrap;
  z-index: 1000;
  font-size: 0.9rem;
}

.cookie-banner.hidden { display: none; }

.cookie-banner a { color: var(--accent); }

.cookie-banner button {
  padding: 0.5rem 1rem;
  background: var(--success);
  color: #fff;
  border: none;
  border-radius: 6px;
  cursor: pointer;
  font-weight: 600;
}

/* ── Share-Buttons (WhatsApp, X, Telegram) ── */
.share {
  margin: 2.25rem auto 1.5rem;
  padding: 1.25rem 1rem;
  max-width: 720px;
  text-align: center;
}

.share-label {
  margin: 0 0 0.75rem;
  font-size: 0.9rem;
  font-weight: 600;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.share-buttons {
  display: flex;
  flex-wrap: wrap;
  gap: 0.55rem;
  justify-content: center;
  align-items: center;
}

.share-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  min-height: 2.25rem;
  padding: 0.35rem 0.75rem;
  border-radius: 10px;
  font-size: 0.8125rem;
  font-weight: 600;
  text-decoration: none !important;
  color: #fff !important;
  border: none;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.12);
  transition: transform 0.18s ease, box-shadow 0.18s ease, filter 0.18s ease, background-color 0.18s ease;
}

.share-button:hover {
  transform: translateY(-1px) scale(1.02);
  box-shadow: 0 4px 14px rgba(0, 0, 0, 0.16);
  filter: brightness(0.92);
}

.share-button:active {
  transform: translateY(0) scale(0.98);
}

.share-button-icon {
  display: inline-flex;
  flex: 0 0 auto;
  flex-shrink: 0;
  align-items: center;
  justify-content: center;
  line-height: 0;
  width: 1.125rem;
  height: 1.125rem;
  max-width: 1.125rem;
  max-height: 1.125rem;
  overflow: hidden;
}

/* Feste Icon-Größe (schützt vor fremden svg-Regeln / fehlendem viewBox-Verhalten) */
.share svg,
.share-button-icon svg {
  width: 1.125rem !important;
  height: 1.125rem !important;
  max-width: 18px !important;
  max-height: 18px !important;
  min-width: 0;
  display: block;
  flex: none !important;
  vertical-align: middle;
  overflow: hidden;
}

.share-button--whatsapp {
  background: #25d366;
}

.share-button--whatsapp:hover {
  filter: brightness(0.9);
}

.share-button--x {
  background: #0f1419;
}

.share-button--x:hover {
  background: #1a2228;
  filter: none;
}

.share-button--telegram {
  background: #0088cc;
}

.share-button--telegram:hover {
  filter: brightness(0.92);
}

@media (max-width: 480px) {
  .share-buttons {
    flex-direction: column;
    width: 100%;
    max-width: 280px;
    margin-left: auto;
    margin-right: auto;
  }

  .share-button {
    width: 100%;
    justify-content: center;
  }
}

/* ── Biquad / IIR-Koeffizienten-Rechner (Elektrotechnik-Berichte) ── */
.filter-calculator {
  margin: 2rem 0;
  padding: 1.75rem 1.5rem;
  border-radius: var(--radius-md);
  border: 1px solid var(--border);
  background: linear-gradient(165deg, var(--bg-surface) 0%, var(--bg-card) 100%);
  box-shadow: var(--shadow-soft);
}

.filter-calculator > h2 {
  margin: 0 0 0.35rem;
  font-size: 1.35rem;
  letter-spacing: -0.02em;
}

.filter-calculator > p:first-of-type {
  margin: 0 0 1.25rem;
  color: var(--text-muted);
  font-size: 0.95rem;
}

.filter-calc-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1rem 1.25rem;
}

@media (max-width: 720px) {
  .filter-calc-grid {
    grid-template-columns: 1fr;
  }
}

.filter-calc-field label {
  display: block;
  font-weight: 600;
  font-size: 0.82rem;
  margin-bottom: 0.4rem;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.filter-calc-field input {
  width: 100%;
  padding: 0.65rem 0.8rem;
  border: 1px solid var(--border);
  border-radius: 10px;
  font-family: var(--font-mono);
  font-size: 0.95rem;
  background: var(--bg-card);
  color: var(--text);
  transition: border-color 0.15s ease, box-shadow 0.15s ease;
}

.filter-calc-field input:focus {
  outline: none;
  border-color: var(--accent);
  box-shadow: 0 0 0 3px rgba(89, 185, 124, 0.2);
}

.filter-calc-actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  gap: 0.65rem;
  margin-top: 1.35rem;
}

.filter-calc-btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  padding: 0.72rem 1.2rem;
  border: none;
  border-radius: 10px;
  font-weight: 600;
  font-size: 0.9rem;
  font-family: var(--font-sans);
  cursor: pointer;
  background: var(--accent);
  color: #fff;
  box-shadow: 0 2px 10px rgba(89, 185, 124, 0.35);
  transition: transform 0.15s ease, filter 0.15s ease, box-shadow 0.15s ease;
}

.filter-calc-btn:hover {
  filter: brightness(1.05);
  transform: translateY(-1px);
}

.filter-calc-btn:active {
  transform: translateY(0);
}

.filter-calc-btn-secondary {
  background: var(--bg-card);
  color: var(--text);
  border: 1px solid var(--border);
  box-shadow: none;
}

.filter-calc-btn-secondary:hover {
  filter: none;
  background: var(--bg-alt);
}

.filter-calc-result {
  margin-top: 1.5rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border);
}

.filter-calc-result h3 {
  margin: 1.25rem 0 0.65rem;
  font-size: 1.05rem;
}

.filter-calc-result h3:first-child {
  margin-top: 0;
}

.filter-calc-coef-grid {
  display: grid;
  grid-template-columns: repeat(5, minmax(0, 1fr));
  gap: 0.5rem;
  margin: 0.75rem 0 1rem;
}

@media (max-width: 640px) {
  .filter-calc-coef-grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

.filter-calc-coef-card {
  padding: 0.65rem 0.5rem;
  border-radius: 10px;
  background: var(--bg-highlight);
  border: 1px solid var(--border);
  text-align: center;
}

.filter-calc-coef-card .coef-name {
  display: block;
  font-size: 0.72rem;
  font-weight: 700;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: 0.25rem;
}

.filter-calc-coef-card .coef-val {
  font-family: var(--font-mono);
  font-size: 0.78rem;
  word-break: break-all;
  color: var(--text);
  line-height: 1.35;
}

.filter-calc-meta {
  font-size: 0.85rem;
  color: var(--text-muted);
  margin: 0 0 1rem;
  font-family: var(--font-mono);
  line-height: 1.5;
}

.filter-calc-pre {
  overflow-x: auto;
  padding: 1rem 1.1rem;
  margin: 0.5rem 0 0;
  border-radius: 10px;
  background: var(--bg-elevated, #eef0f4);
  border: 1px solid var(--border);
  font-family: var(--font-mono);
  font-size: 0.82rem;
  line-height: 1.5;
}

.filter-calc-msg {
  padding: 0.85rem 1rem;
  border-radius: 10px;
  font-size: 0.92rem;
}

.filter-calc-msg--error {
  background: rgba(248, 81, 73, 0.08);
  border: 1px solid rgba(248, 81, 73, 0.35);
  color: var(--danger);
}

.filter-calc-msg--hint {
  background: var(--bg-highlight);
  border: 1px solid var(--border);
  color: var(--text-muted);
}