/* ==========================================================================
   People.Tech.Connect. – Microlearning Hub
   Design-System basierend auf PTC Corporate Design
   ========================================================================== */

/* --- Custom Properties (Farben aus PTC-Design) --- */
:root {
  /* Primärfarben (aus PTC-Branding) */
  --ptc-blue: #3a7cc2;
  --ptc-green: #8ab528;
  --ptc-purple: #5b2d7e;

  /* Flächenfarben (wie auf people-tech-connect.de) */
  --ptc-purple-bg: #5b2d7e;
  --ptc-purple-dark: #4a2066;
  --ptc-green-dark: #3d6b4f;
  --ptc-green-olive: #4a7a5a;
  --ptc-teal: #6a9fa8;
  --ptc-teal-light: #e8f2f4;
  --ptc-speaker-bg: #d5ddd8;
  --ptc-gradient-bg: linear-gradient(135deg, #6a9fa8 0%, #87b5a0 50%, #a3c48e 100%);
  --ptc-gradient-hero: linear-gradient(160deg, #6a9fa8 0%, #7fb5a3 40%, #96c49a 100%);

  /* Neutrals */
  --white: #ffffff;
  --gray-50: #f8f9fa;
  --gray-100: #f0f1f3;
  --gray-200: #e2e4e8;
  --gray-300: #c5c8ce;
  --gray-500: #6b7280;
  --gray-700: #374151;
  --gray-900: #1a1a2e;

  /* Typo */
  --font-main: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-weight-regular: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Spacing */
  --space-xs: 0.25rem;
  --space-sm: 0.5rem;
  --space-md: 1rem;
  --space-lg: 1.5rem;
  --space-xl: 2rem;
  --space-2xl: 3rem;
  --space-3xl: 4rem;
  --space-4xl: 6rem;

  /* Layout */
  --max-width: 1140px;
  --border-radius: 12px;
  --border-radius-sm: 8px;
  --border-radius-lg: 20px;

  /* Shadows */
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.08);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.1);
  --shadow-lg: 0 8px 30px rgba(0,0,0,0.12);
  --shadow-card: 0 2px 8px rgba(0,0,0,0.06), 0 8px 24px rgba(0,0,0,0.08);
}

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

html {
  font-size: 16px;
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-main);
  font-weight: var(--font-weight-regular);
  color: var(--gray-700);
  background-color: var(--white);
  line-height: 1.6;
}

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

a {
  color: var(--ptc-purple);
  text-decoration: none;
  transition: color 0.2s ease;
}

a:hover {
  color: var(--ptc-blue);
}

/* --- Container --- */
.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--space-lg);
}

/* --- Header / Hero --- */
.hero {
  background: var(--ptc-gradient-hero);
  padding: var(--space-md) 0 var(--space-2xl);
  text-align: center;
  position: relative;
  overflow: hidden;
  color: var(--white);
}

.hero::before {
  content: '';
  position: absolute;
  left: -100px;
  bottom: -100px;
  width: 350px;
  height: 350px;
  background: rgba(255,255,255,0.05);
  border-radius: 50%;
}

.hero::after {
  content: '';
  position: absolute;
  right: -50px;
  top: -50px;
  width: 200px;
  height: 200px;
  background: rgba(255,255,255,0.04);
  border-radius: 50%;
}

.hero__top-meta {
  font-size: 0.9rem;
  color: rgba(255,255,255,0.8);
  margin-bottom: var(--space-lg);
  letter-spacing: 0.02em;
}

.hero__logo {
  width: 380px;
  max-width: 80%;
  margin: 0 auto var(--space-md);
  position: relative;
  z-index: 1;
  background: rgba(255,255,255,0.92);
  border-radius: var(--border-radius);
  padding: var(--space-md) var(--space-xl);
}

.hero__badge {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  padding: var(--space-sm) var(--space-xl);
  background: rgba(255,255,255,0.2);
  backdrop-filter: blur(4px);
  color: var(--white);
  border: 1px solid rgba(255,255,255,0.3);
  border-radius: 30px;
  margin-bottom: var(--space-md);
  position: relative;
  z-index: 1;
}

.hero__subtitle {
  font-size: 1.05rem;
  color: rgba(255,255,255,0.9);
  max-width: 560px;
  margin: 0 auto var(--space-lg);
  line-height: 1.6;
  position: relative;
  z-index: 1;
}

.hero__meta {
  display: flex;
  justify-content: center;
  gap: var(--space-xl);
  flex-wrap: wrap;
  font-size: 0.9rem;
  color: rgba(255,255,255,0.8);
  position: relative;
  z-index: 1;
}

.hero__meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.hero__meta-item svg {
  width: 16px;
  height: 16px;
  color: var(--white);
  flex-shrink: 0;
}

/* --- Intro-Sektion (violetter Hintergrund mit Molekül-Deko) --- */
.intro {
  padding: var(--space-3xl) 0 var(--space-2xl);
  background: var(--ptc-purple-bg);
  color: var(--white);
  position: relative;
  overflow: hidden;
}

/* Molekül-Grafik als dezentes Hintergrundelement (exakte PTC-Form) */
.intro__molecule {
  position: absolute;
  left: -40px;
  top: 50%;
  transform: translateY(-55%);
  width: 340px;
  height: 450px;
  opacity: 0.1;
  pointer-events: none;
}

.intro__molecule--right {
  left: auto;
  right: -60px;
  top: auto;
  bottom: -60px;
  transform: scaleX(-1) rotate(20deg);
  opacity: 0.06;
  width: 260px;
  height: 350px;
}

.intro__inner {
  position: relative;
  z-index: 1;
  max-width: 800px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr;
  gap: var(--space-xl);
  text-align: center;
}

.intro__heading {
  font-size: 1.4rem;
  font-weight: var(--font-weight-bold);
  color: var(--white);
  margin-bottom: var(--space-xs);
}

.intro__text {
  font-size: 1.05rem;
  line-height: 1.8;
  color: rgba(255,255,255,0.88);
  max-width: 640px;
  margin: 0 auto;
}

.intro__highlights {
  display: flex;
  justify-content: center;
  gap: var(--space-lg);
  flex-wrap: wrap;
  margin-top: var(--space-sm);
}

.intro__highlight {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  background: rgba(255,255,255,0.1);
  padding: var(--space-sm) var(--space-lg);
  border-radius: 30px;
  font-size: 0.9rem;
  color: rgba(255,255,255,0.9);
  border: 1px solid rgba(255,255,255,0.15);
}

.intro__highlight svg {
  width: 18px;
  height: 18px;
  flex-shrink: 0;
  color: rgba(255,255,255,0.7);
}

/* --- Session-Karten Grid --- */
.sessions {
  padding: var(--space-3xl) 0 var(--space-4xl);
  background: var(--gray-50);
}

.sessions__title {
  font-size: clamp(1.5rem, 3vw, 2rem);
  font-weight: var(--font-weight-bold);
  text-align: center;
  margin-bottom: var(--space-sm);
  color: var(--gray-900);
}

.sessions__title span {
  color: var(--ptc-green);
}

.sessions__subtitle {
  text-align: center;
  color: var(--gray-500);
  margin-bottom: var(--space-2xl);
  font-size: 1.05rem;
}

/* Themencluster-Überschriften */
.cluster {
  margin-bottom: var(--space-2xl);
  background: var(--white);
  border-radius: var(--border-radius);
  padding: var(--space-xl) var(--space-xl) var(--space-2xl);
  box-shadow: var(--shadow-sm);
}

.cluster__label {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.1em;
  text-transform: uppercase;
  padding: var(--space-xs) var(--space-md);
  border-radius: 20px;
  margin-bottom: var(--space-lg);
}

.cluster__label--keynote {
  background: var(--ptc-purple);
  color: var(--white);
}

.cluster__label--parallel-1 {
  background: var(--ptc-blue);
  color: var(--white);
}

.cluster__label--parallel-2 {
  background: var(--ptc-green);
  color: var(--white);
}

.cluster__label--plenum {
  background: var(--gray-700);
  color: var(--white);
}

.cluster__time {
  font-size: 0.9rem;
  color: var(--gray-500);
  margin-bottom: var(--space-lg);
}

/* Card Grid */
.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(320px, 1fr));
  gap: var(--space-xl);
}

.card-grid--single {
  grid-template-columns: 1fr;
  max-width: 680px;
}

/* Session Card */
.card {
  background: var(--white);
  border-radius: var(--border-radius);
  box-shadow: var(--shadow-card);
  overflow: hidden;
  transition: transform 0.25s ease, box-shadow 0.25s ease;
  display: flex;
  flex-direction: column;
  text-decoration: none;
  color: inherit;
}

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

.card__accent {
  height: 6px;
  background: var(--ptc-purple);
}

.card__accent--blue { background: var(--ptc-blue); }
.card__accent--green { background: var(--ptc-green); }
.card__accent--purple { background: var(--ptc-purple); }
.card__accent--gradient { background: linear-gradient(90deg, var(--ptc-blue), var(--ptc-green), var(--ptc-purple)); }

.card__body {
  padding: var(--space-xl);
  flex: 1;
  display: flex;
  flex-direction: column;
}

.card__time {
  font-size: 0.82rem;
  font-weight: var(--font-weight-semibold);
  color: var(--ptc-purple);
  margin-bottom: var(--space-sm);
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.card__time svg {
  width: 14px;
  height: 14px;
}

.card__title {
  font-size: 1.15rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-sm);
  line-height: 1.35;
}

.card__speaker {
  font-size: 0.9rem;
  color: var(--gray-500);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.card__speaker-img {
  width: 36px;
  height: 36px;
  border-radius: 50%;
  object-fit: cover;
  border: 2px solid var(--ptc-purple);
}

.card__tags {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-xs);
  margin-top: auto;
  padding-top: var(--space-md);
}

.tag {
  font-size: 0.75rem;
  font-weight: var(--font-weight-medium);
  padding: 3px 10px;
  border-radius: 20px;
  background: var(--ptc-teal-light);
  color: var(--ptc-teal);
}

.tag--audio {
  background: #f3e8ff;
  color: var(--ptc-purple);
}

.tag--slides {
  background: #e8f5e9;
  color: #2e7d32;
}

.tag--photos {
  background: #fff3e0;
  color: #e65100;
}

/* --- Footer --- */
.footer {
  background: var(--ptc-purple-dark);
  color: rgba(255,255,255,0.7);
  padding: var(--space-2xl) 0;
  text-align: center;
  font-size: 0.9rem;
}

.footer a {
  color: var(--gray-200);
}

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

.footer__logos {
  display: flex;
  justify-content: center;
  align-items: center;
  gap: var(--space-xl);
  margin-bottom: var(--space-lg);
  flex-wrap: wrap;
}

.footer__logo {
  height: 32px;
  opacity: 0.7;
  filter: brightness(0) invert(1);
  transition: opacity 0.2s ease;
}

.footer__logo:hover {
  opacity: 1;
}

.footer__divider {
  width: 60px;
  height: 2px;
  background: var(--ptc-purple);
  margin: var(--space-lg) auto;
}

/* ==========================================================================
   Session-Einzelseite
   ========================================================================== */

/* --- Session Hero --- */
.session-hero {
  background: var(--ptc-gradient-hero);
  color: var(--white);
  padding: var(--space-3xl) 0 var(--space-2xl);
  position: relative;
  overflow: hidden;
}

.session-hero::after {
  content: '';
  position: absolute;
  right: -60px;
  top: -60px;
  width: 250px;
  height: 250px;
  background: rgba(255,255,255,0.06);
  border-radius: 50%;
}

.session-hero__back {
  display: inline-flex;
  align-items: center;
  gap: var(--space-xs);
  font-size: 0.9rem;
  color: rgba(255,255,255,0.8);
  margin-bottom: var(--space-xl);
  transition: color 0.2s ease;
}

.session-hero__back:hover {
  color: var(--white);
}

.session-hero__back svg {
  width: 16px;
  height: 16px;
}

.session-hero__label {
  display: inline-block;
  font-size: 0.8rem;
  font-weight: var(--font-weight-semibold);
  letter-spacing: 0.08em;
  text-transform: uppercase;
  padding: var(--space-xs) var(--space-md);
  background: rgba(255,255,255,0.2);
  border-radius: 20px;
  margin-bottom: var(--space-md);
}

.session-hero__title {
  font-size: clamp(1.6rem, 3.5vw, 2.4rem);
  font-weight: var(--font-weight-bold);
  line-height: 1.25;
  margin-bottom: var(--space-md);
  max-width: 800px;
}

.session-hero__meta {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-lg);
  font-size: 0.95rem;
  opacity: 0.9;
}

.session-hero__meta-item {
  display: flex;
  align-items: center;
  gap: var(--space-xs);
}

.session-hero__meta-item svg {
  width: 16px;
  height: 16px;
}

/* --- Speaker-Info auf Session-Seite --- */
.speaker-box {
  background: var(--gray-50);
  border-radius: var(--border-radius);
  padding: var(--space-xl);
  display: flex;
  gap: var(--space-xl);
  align-items: flex-start;
  margin: var(--space-2xl) 0;
}

.speaker-box__img {
  width: 100px;
  height: 100px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--ptc-purple);
  flex-shrink: 0;
}

.speaker-box__name {
  font-size: 1.15rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-xs);
}

.speaker-box__role {
  font-size: 0.9rem;
  color: var(--gray-500);
  margin-bottom: var(--space-sm);
}

.speaker-box__bio {
  font-size: 0.95rem;
  line-height: 1.6;
  color: var(--gray-700);
}

/* --- Session-Content --- */
.session-content {
  padding: var(--space-3xl) 0;
}

.session-content__inner {
  max-width: 780px;
  margin: 0 auto;
}

/* Microlearning-Abschnitte */
.learning-section {
  margin-bottom: var(--space-3xl);
}

.learning-section__title {
  font-size: 1.4rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-md);
  padding-bottom: var(--space-sm);
  border-bottom: 2px solid var(--ptc-purple);
}

.learning-section__text {
  font-size: 1.05rem;
  line-height: 1.8;
  color: var(--gray-700);
}

.learning-section__text p {
  margin-bottom: var(--space-md);
}

/* Einzelne Erkenntnis-Blöcke */
.insight {
  display: flex;
  gap: var(--space-lg);
  padding: var(--space-lg) var(--space-xl);
  border-left: 4px solid var(--insight-color, var(--ptc-purple));
  background: var(--insight-bg, #f9f5ff);
  border-radius: 0 var(--border-radius-sm) var(--border-radius-sm) 0;
  margin-bottom: var(--space-lg);
  transition: transform 0.15s ease;
}

.insight:last-child {
  margin-bottom: 0;
}

.insight__number {
  flex-shrink: 0;
  width: 36px;
  height: 36px;
  border-radius: 50%;
  background: var(--insight-color, var(--ptc-purple));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: var(--font-weight-bold);
  font-size: 0.95rem;
  margin-top: 2px;
}

.insight__content h3 {
  font-size: 1.1rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-sm);
}

.insight__content p {
  font-size: 1rem;
  line-height: 1.75;
  color: var(--gray-700);
  margin: 0;
}

@media (max-width: 480px) {
  .insight {
    padding: var(--space-md);
    gap: var(--space-md);
  }
  .insight__number {
    width: 30px;
    height: 30px;
    font-size: 0.85rem;
  }
}

/* Key Takeaways */
.takeaways {
  background: linear-gradient(135deg, #f3e8ff 0%, #ede4f7 100%);
  border-radius: var(--border-radius);
  padding: var(--space-xl);
  margin: var(--space-2xl) 0;
}

.takeaways__title {
  font-size: 1.1rem;
  font-weight: var(--font-weight-bold);
  color: var(--ptc-purple);
  margin-bottom: var(--space-md);
  display: flex;
  align-items: center;
  gap: var(--space-sm);
}

.takeaways__list {
  list-style: none;
  padding: 0;
}

.takeaways__list li {
  padding: var(--space-sm) 0;
  padding-left: var(--space-lg);
  position: relative;
  font-size: 1rem;
  line-height: 1.6;
}

.takeaways__list li::before {
  content: '';
  position: absolute;
  left: 0;
  top: 0.85rem;
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--bullet-color, var(--ptc-purple));
}

/* Leitfragen */
.questions {
  background: var(--ptc-teal-light);
  border-radius: var(--border-radius);
  padding: var(--space-xl);
  margin: var(--space-2xl) 0;
  border-left: 4px solid var(--ptc-teal);
}

.questions__title {
  font-size: 1.1rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-md);
}

.questions__list {
  list-style: none;
  padding: 0;
}

.questions__list li {
  padding: var(--space-sm) 0;
  font-size: 1rem;
  line-height: 1.6;
  font-style: italic;
  color: var(--gray-700);
}

/* Slides/Medien */
.media-section {
  margin: var(--space-2xl) 0;
}

.media-section__title {
  font-size: 1.1rem;
  font-weight: var(--font-weight-bold);
  color: var(--gray-900);
  margin-bottom: var(--space-md);
}

.media-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(240px, 1fr));
  gap: var(--space-md);
}

.media-item {
  border-radius: var(--border-radius-sm);
  overflow: hidden;
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  transition: transform 0.2s ease;
}

.media-item:hover {
  transform: scale(1.02);
}

.media-item img {
  width: 100%;
  aspect-ratio: 16/10;
  object-fit: cover;
}

/* Placeholder für Content */
.placeholder {
  background: var(--gray-100);
  border: 2px dashed var(--gray-300);
  border-radius: var(--border-radius);
  padding: var(--space-2xl);
  text-align: center;
  color: var(--gray-500);
  font-size: 0.95rem;
}

.placeholder__icon {
  font-size: 2rem;
  margin-bottom: var(--space-sm);
}

/* --- Navigation zwischen Sessions --- */
.session-nav {
  display: flex;
  justify-content: space-between;
  gap: var(--space-md);
  padding: var(--space-2xl) 0;
  border-top: 1px solid var(--gray-200);
  margin-top: var(--space-2xl);
}

.session-nav__link {
  display: flex;
  align-items: center;
  gap: var(--space-sm);
  font-size: 0.95rem;
  font-weight: var(--font-weight-medium);
  color: var(--ptc-purple);
  padding: var(--space-md) var(--space-lg);
  border-radius: var(--border-radius-sm);
  border: 1px solid var(--gray-200);
  transition: all 0.2s ease;
  max-width: 48%;
}

.session-nav__link:hover {
  background: var(--gray-50);
  border-color: var(--ptc-purple);
  color: var(--ptc-purple);
}

.session-nav__link svg {
  width: 16px;
  height: 16px;
  flex-shrink: 0;
}

.session-nav__link--next {
  margin-left: auto;
  text-align: right;
}

/* ==========================================================================
   Responsive
   ========================================================================== */

@media (max-width: 768px) {
  .hero {
    padding: var(--space-2xl) 0 var(--space-xl);
  }

  .hero__meta {
    flex-direction: column;
    align-items: center;
    gap: var(--space-sm);
  }

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

  .speaker-box {
    flex-direction: column;
    align-items: center;
    text-align: center;
  }

  .session-nav {
    flex-direction: column;
  }

  .session-nav__link {
    max-width: 100%;
  }

  .session-hero {
    padding: var(--space-2xl) 0 var(--space-xl);
  }
}

@media (max-width: 480px) {
  .hero__logo {
    width: 150px;
  }

  .card__body {
    padding: var(--space-lg);
  }

  .container {
    padding: 0 var(--space-md);
  }
}