:root {
  --accent: #0f62fe;
  --bg: #0f1720;
  --card: #0b1220;
  --muted: #9aa6b2;
  --text: #e6eef6;
  --teal: #2dd4bf;
  --page-top: #071021;
  --page-bottom: #071522;
  --surface-panel: linear-gradient(180deg, rgba(255, 255, 255, 0.025), rgba(255, 255, 255, 0.01));
  --surface-card: linear-gradient(180deg, rgba(255, 255, 255, 0.03), rgba(255, 255, 255, 0.015));
  --surface-soft: rgba(255, 255, 255, 0.04);
  --border-soft: rgba(255, 255, 255, 0.05);
  --border-card: rgba(255, 255, 255, 0.08);
  --shadow-panel: 0 4px 12px rgba(0, 0, 0, 0.3);
  --shadow-card: 0 10px 24px rgba(2, 6, 23, 0.34);
  --focus-ring: 0 0 0 4px rgba(15, 98, 254, 0.16);
  color-scheme: dark;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family: Inter, ui-sans-serif, system-ui, "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  background: linear-gradient(180deg, var(--page-top) 0%, var(--page-bottom) 100%);
  color: var(--text);
  -webkit-font-smoothing: antialiased;
}

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

a:hover,
a:focus-visible {
  color: var(--teal);
}

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

.container {
  max-width: 1100px;
  margin: 40px auto;
  padding: 24px;
}

.brand {
  display: flex;
  gap: 12px;
  align-items: center;
}

.brand-copy h1,
h1 {
  margin: 0;
  font-size: 20px;
}

.brand-subtitle {
  font-size: 13px;
  color: var(--muted);
}

.logo {
  width: 48px;
  height: 48px;
  border-radius: 8px;
  background: linear-gradient(135deg, var(--accent), var(--teal));
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 700;
  color: #04263b;
}

header {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 20px;
  margin-bottom: 28px;
  position: relative;
}

nav {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  align-items: center;
  padding: 0;
}

nav a {
  color: var(--muted);
  font-size: 12px;
  padding: 6px 12px;
  border-radius: 999px;
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid var(--border-soft);
  box-shadow: none;
  transition: background 0.2s ease, color 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
  display: inline-flex;
  align-items: center;
}

nav a:hover,
nav a:focus-visible {
  background: linear-gradient(90deg, var(--accent), var(--teal));
  border-color: transparent;
  color: #04263b;
  box-shadow: 0 8px 18px rgba(15, 98, 254, 0.22);
}

main,
section,
article,
aside,
footer {
  min-width: 0;
}

.card {
  padding: 20px;
  border-radius: 12px;
  margin-bottom: 24px;
  background: var(--surface-card);
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-card);
}

.card h3 {
  margin: 0 0 16px;
  color: var(--accent);
}

.card p,
.card li {
  color: var(--muted);
}

button,
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 10px 14px;
  border-radius: 10px;
  border: 1px solid transparent;
  cursor: pointer;
  font: inherit;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease, background 0.2s ease, color 0.2s ease;
}

button,
.btn-primary {
  background: linear-gradient(135deg, var(--accent), var(--teal));
  color: #04263b;
  box-shadow: 0 8px 20px rgba(15, 98, 254, 0.22);
}

button:hover,
.btn:hover {
  transform: translateY(-1px);
}

button:focus-visible,
.btn:focus-visible,
input:focus-visible,
textarea:focus-visible,
select:focus-visible {
  outline: none;
  box-shadow: var(--focus-ring);
}

.btn-ghost {
  background: rgba(255, 255, 255, 0.03);
  border-color: var(--border-card);
  color: var(--text);
  box-shadow: none;
}

.btn-ghost:hover,
.btn-ghost:focus-visible {
  background: rgba(255, 255, 255, 0.06);
}

label {
  color: var(--muted);
  font-size: 14px;
}

input,
textarea,
select {
  width: 100%;
  padding: 12px;
  border: 1px solid var(--border-card);
  border-radius: 10px;
  background: rgba(255, 255, 255, 0.04);
  color: var(--text);
  font: inherit;
}

input::placeholder,
textarea::placeholder {
  color: var(--muted);
}

.site-footer {
  text-align: center;
  padding: 20px;
  margin-top: 40px;
  color: var(--muted);
  border-radius: 12px;
  background: var(--surface-card);
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-card);
}

.qualifikationen-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(120px, 1fr));
  gap: 20px;
}

.qualifikationen-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  text-align: center;
}

.qualifikationen-item img,
.qualifikationen-item .pdf-thumb {
  width: 100%;
  border-radius: 10px;
  cursor: pointer;
  transition: transform 0.2s ease, border-color 0.2s ease, box-shadow 0.2s ease;
  object-fit: contain;
  height: 100%;
  background: rgba(255, 255, 255, 0.03);
  color: var(--muted);
  display: flex;
  align-items: center;
  justify-content: center;
  border: 1px solid var(--border-soft);
}

.qualifikationen-item img:hover,
.qualifikationen-item .pdf-thumb:hover {
  transform: scale(2.05);
  border-color: rgba(15, 98, 254, 0.22);
  box-shadow: var(--shadow-card);
}

.qualifikationen-item span {
  margin-top: 6px;
  font-size: 14px;
  color: var(--muted);
}

.download-link {
  margin-top: 4px;
  font-size: 12px;
  font-weight: 600;
  color: var(--accent);
}

.download-link:hover,
.download-link:focus-visible {
  color: var(--teal);
}

.lightbox {
  position: fixed;
  inset: 0;
  background: rgba(2, 6, 23, 0.9);
  display: flex;
  align-items: center;
  justify-content: center;
  visibility: hidden;
  opacity: 0;
  transition: opacity 0.3s ease;
  z-index: 9999;
}

.lightbox.active {
  visibility: visible;
  opacity: 1;
}

.lightbox-content {
  max-width: 90%;
  max-height: 90%;
}

.lightbox-content iframe,
.lightbox-content img {
  max-width: 100%;
  max-height: 100%;
  border-radius: 12px;
  border: 1px solid var(--border-card);
  box-shadow: var(--shadow-card);
}

.lightbox .nav {
  position: absolute;
  top: 50%;
  transform: translateY(-50%);
  font-size: 32px;
  color: var(--text);
  cursor: pointer;
  user-select: none;
  padding: 20px;
}

.lightbox .prev {
  left: 0;
}

.lightbox .next {
  right: 0;
}

@media (max-width: 900px) {
  .container {
    margin: 24px auto;
    padding: 18px;
  }

  header {
    flex-direction: column;
    align-items: flex-start;
  }

  nav {
    width: 100%;
  }
}