/* =========================================================
   DESIGN TOKENS
   Ein zentraler Satz an Variablen — spätere Sektionen greifen
   nur hierauf zu, nichts wird hart codiert.
   ========================================================= */
:root {
  /* Farben */
  --color-bg: #ffffff;
  --color-bg-alt: #f5f5f7;       /* sekundäre Sektionen, Apple-typisches Hellgrau */
  --color-text: #1d1d1f;          /* Haupttext, fast Schwarz */
  --color-text-secondary: #6e6e73;
  --color-accent: #0a3d91;        /* Trust Blue */
  --color-accent-hover: #0c4bb0;
  --color-border: #e5e5e7;
  --color-footer-bg: #081c3d;     /* tiefes Trust-Blue, fast Schwarz, für den Abschluss */
  --color-footer-text: rgba(255, 255, 255, 0.72);

  /* Typografie */
  --font-base: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;

  /* Layout */
  --container-width: 1120px;
  --space-xs: 8px;
  --space-sm: 16px;
  --space-md: 24px;
  --space-lg: 48px;
  --space-xl: 96px;

  /* Sonstiges */
  --radius: 8px;
  --radius-pill: 999px;
  --transition: 0.2s ease;
}

/* =========================================================
   RESET & BASISVERHALTEN
   ========================================================= */
*,
*::before,
*::after {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: var(--font-base);
  color: var(--color-text);
  background-color: var(--color-bg);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3 {
  margin: 0;
  font-weight: 700;
  letter-spacing: -0.01em;
}

p {
  margin: 0;
}

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

ul {
  list-style: none;
  margin: 0;
  padding: 0;
}

/* Sichtbarer Fokus-Ring für Tastaturnutzung (Barrierefreiheit) */
a:focus-visible,
button:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 3px;
}

/* Reduzierte Bewegung respektieren */
@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  * {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}

/* =========================================================
   LAYOUT-HILFSKLASSEN
   ========================================================= */
.container {
  width: 100%;
  max-width: var(--container-width);
  margin-inline: auto;
  padding-inline: var(--space-md);
}

/* =========================================================
   HEADER / NAVIGATION
   ========================================================= */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.8);
  backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--color-border);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-weight: 600;
  font-size: 1.05rem;
}

.main-nav ul {
  display: flex;
  gap: var(--space-lg);
}

.main-nav a {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  transition: color var(--transition);
}

.main-nav a:hover {
  color: var(--color-text);
}

/* =========================================================
   HERO-SEKTION
   ========================================================= */
.hero {
  padding-block: var(--space-xl);
}

.hero-inner {
  max-width: 760px;

  /* Der einzige orchestrierte Motion-Moment der Seite */
  animation: fade-in-up 0.8s ease both;
}

@keyframes fade-in-up {
  from {
    opacity: 0;
    transform: translateY(16px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

.hero-greeting {
  font-size: 1.1rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  margin-bottom: var(--space-sm);
}

.hero-title {
  font-size: clamp(2.25rem, 5vw, 3.5rem);
  line-height: 1.1;
  margin-bottom: var(--space-md);
}

.hero-text {
  font-size: 1.15rem;
  color: var(--color-text-secondary);
  max-width: 640px;
  margin-bottom: var(--space-lg);
}

.hero-actions {
  display: flex;
  flex-wrap: wrap;
  gap: var(--space-sm);
}

/* =========================================================
   BUTTONS
   ========================================================= */
.btn {
  display: inline-block;
  padding: 14px 28px;
  border-radius: var(--radius);
  font-size: 1rem;
  font-weight: 600;
  transition: background-color var(--transition), color var(--transition), border-color var(--transition);
}

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

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

.btn-secondary {
  background-color: transparent;
  color: var(--color-text);
  border: 1px solid var(--color-border);
}

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

/* =========================================================
   HIGHLIGHTS: CARD-SEKTION (Auftrag 2)
   ========================================================= */
.cards-section {
  background-color: var(--color-bg-alt);
}

.cards-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--space-md);
}

.card {
  display: flex;
  flex-direction: column;
  gap: var(--space-sm);
  background-color: #ffffff;
  border-radius: var(--radius);
  padding: var(--space-lg) var(--space-md);
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.05);
  transition: box-shadow var(--transition), transform var(--transition);
}

.card:hover {
  box-shadow: 0 8px 20px rgba(0, 0, 0, 0.08);
  transform: translateY(-2px);
}

.card-title {
  font-size: 1.15rem;
}

.card-text {
  color: var(--color-text-secondary);
  font-size: 0.98rem;
}

.card-image-placeholder {
  height: 140px;
  border: 1px dashed var(--color-border);
  border-radius: var(--radius);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-secondary);
  font-size: 0.9rem;
  background-color: var(--color-bg-alt);
}

.card-link {
  font-size: 0.95rem;
  font-weight: 600;
  color: var(--color-accent);
  margin-top: auto;
  transition: color var(--transition);
}

.card-link:hover {
  color: var(--color-accent-hover);
}

/* Dreispaltiges Bild-Grid für Projekt-Screenshots innerhalb einer Karte */
.project-images {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: var(--space-xs);
  margin-top: auto;
}

.project-images img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  border-radius: 6px;
  display: block;
  border: 1px solid var(--color-border);
  cursor: pointer;
  transition: opacity var(--transition);
}

.project-images img:hover {
  opacity: 0.85;
}

/* Auf sehr schmalen Karten (z. B. Mobile) lieber untereinander statt gequetscht */
@media (max-width: 420px) {
  .project-images {
    grid-template-columns: 1fr;
  }
}

/* Kompakte Download-Buttons innerhalb der Zertifikats-Karte */
.cert-downloads {
  display: flex;
  flex-direction: column;
  gap: var(--space-xs);
  margin-top: auto;
}

.cert-download-btn {
  display: block;
  padding: 10px 14px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  font-size: 0.88rem;
  font-weight: 500;
  color: var(--color-text-secondary);
  text-align: center;
  transition: border-color var(--transition), color var(--transition), background-color var(--transition);
}

.cert-download-btn:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
  background-color: var(--color-bg-alt);
}

/* =========================================================
   ALLGEMEINE SEKTIONEN (Platzhalter für kommende Aufträge)
   ========================================================= */
.section {
  padding-block: var(--space-xl);
  border-top: 1px solid var(--color-border);
}

.section-alt {
  background-color: var(--color-bg-alt);
}

.section h2 {
  font-size: clamp(1.5rem, 3vw, 2rem);
}

/* =========================================================
   TECH-STACK & TOOLS (Auftrag 3)
   ========================================================= */
.skills-section {
  background-color: var(--color-bg);
  text-align: center;
}

.skills-section h2 {
  margin-bottom: var(--space-lg);
}

.skills-list {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-sm);
}

.skill-pill {
  padding: 10px 22px;
  border: 1px solid var(--color-border);
  border-radius: var(--radius-pill);
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--color-text);
  background-color: var(--color-bg-alt);
  transition: border-color var(--transition), color var(--transition);
}

.skill-pill:hover {
  border-color: var(--color-accent);
  color: var(--color-accent);
}

/* =========================================================
   FOOTER / KONTAKT (Auftrag 3)
   ========================================================= */
.site-footer {
  background-color: var(--color-footer-bg);
  color: var(--color-footer-text);
}

.footer-inner {
  padding-block: var(--space-xl);
  text-align: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--space-lg);
}

.footer-heading {
  color: #ffffff;
  font-size: clamp(1.5rem, 3vw, 2.25rem);
  max-width: 640px;
  line-height: 1.25;
}

.footer-actions {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: var(--space-sm);
}

/* Sekundärer Button braucht auf dunklem Grund eigene Farben,
   damit er nicht mit dem hellen Standard-Secondary kollidiert. */
.btn-on-dark.btn-secondary {
  color: #ffffff;
  border-color: rgba(255, 255, 255, 0.35);
}

.btn-on-dark.btn-secondary:hover {
  border-color: #ffffff;
}

.footer-copyright {
  font-size: 0.85rem;
  color: rgba(255, 255, 255, 0.5);
}

/* =========================================================
   RESPONSIVE ANPASSUNGEN
   ========================================================= */
@media (max-width: 900px) {
  .cards-grid {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 720px) {
  .header-inner {
    height: auto;
    padding-block: var(--space-sm);
    flex-direction: column;
    align-items: flex-start;
    gap: var(--space-sm);
  }

  .main-nav ul {
    flex-wrap: wrap;
    gap: var(--space-md);
  }

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

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

  .btn {
    text-align: center;
  }

  .footer-actions {
    flex-direction: column;
    width: 100%;
    max-width: 320px;
  }
}

/* =========================================================
   LIGHTBOX / MODAL FÜR PROJEKT-BILDER
   ========================================================= */
.lightbox {
  position: fixed;
  inset: 0;
  z-index: 1000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-lg);

  background-color: rgba(0, 0, 0, 0.55);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);

  opacity: 0;
  visibility: hidden;
  transition: opacity var(--transition), visibility var(--transition);
}

.lightbox.is-open {
  opacity: 1;
  visibility: visible;
}

.lightbox-image {
  max-width: min(90vw, 1000px);
  max-height: 85vh;
  border-radius: var(--radius);
  box-shadow: 0 20px 60px rgba(0, 0, 0, 0.35);

  /* Sanftes Hineinwachsen statt hartem Erscheinen */
  transform: scale(0.96);
  transition: transform var(--transition);
}

.lightbox.is-open .lightbox-image {
  transform: scale(1);
}

.lightbox-close {
  position: fixed;
  top: var(--space-md);
  right: var(--space-md);
  width: 40px;
  height: 40px;
  border: none;
  border-radius: 50%;
  background-color: rgba(255, 255, 255, 0.12);
  color: #ffffff;
  font-size: 1.5rem;
  line-height: 1;
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: background-color var(--transition);
}

.lightbox-close:hover {
  background-color: rgba(255, 255, 255, 0.24);
}

@media (prefers-reduced-motion: reduce) {
  .lightbox-image {
    transform: none;
  }
}