:root {
  --color-bg: #f9f9f9;
  --color-text: #222;
  --color-primary: #005475;
  --color-primary-light: #1e4d5f;
  --color-accent: #d88e00;
  --color-accent-light: #ffcc00;
  --color-highlight: #a6c5cd;
  --color-panel: #fff;
  --color-panel-alt: #f0f4f8;
  --color-footer-bg: #005475;
  --color-footer-text: #fff;

  --font-main: 'Arial', sans-serif;

  --radius-sm: 8px;
  --radius-md: 10px;
  --radius-lg: 12px;

  --shadow-sm: 0 2px 6px rgba(0,0,0,0.1);
  --shadow-md: 0 4px 12px rgba(0,0,0,0.08);
  --shadow-lg: 0 6px 16px rgba(0,0,0,0.12);

  --transition: 0.3s ease;
}

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
  font-family: var(--font-main);
}

body {
  line-height: 1.6;
  background: var(--color-bg);
  color: var(--color-text);
}

h1,
h2,
h3 {
  margin-bottom: 0.5em;
  color: #163645;
}

a {
  text-decoration: none;
  color: inherit;
  transition: var(--transition);
}

.navbar {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 2rem;
  background: var(--color-panel);
  box-shadow: var(--shadow-sm);
  position: sticky;
  top: 0;
  z-index: 100;
}

.navbar .logo img {
  height: 50px;
}

#nav-links {
  list-style: none;
  display: flex;
  gap: 1.5rem;
}

#nav-links li a {
  font-weight: 600;
  color: #507090;
}

#nav-links li a:hover {
  color: var(--color-primary-light);
}

.hamburger {
  display: none;
  flex-direction: column;
  cursor: pointer;
  gap: 5px;
}

.hamburger span {
  width: 25px;
  height: 3px;
  background: #333;
}

.hero {
  background: var(--color-primary);
  color: #fff;
  text-align: center;
  padding: 5rem 1rem;
}

.hero h1 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: var(--color-highlight);
}

.hero p {
  font-size: 1.3rem;
  margin-bottom: 2rem;
}

.btn-hero {
  background: var(--color-accent);
  color: #3d5a68;
  padding: 1rem 2rem;
  border-radius: var(--radius-md);
  font-weight: 700;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  box-shadow: 0 4px 10px rgba(0,0,0,0.15);
}

.btn-hero:hover {
  background: var(--color-accent-light);
  transform: translateY(-2px);
}

.content-section {
  padding: 3rem 1rem;
  max-width: 1100px;
  margin: 0 auto;
}

.alt-bg {
  background: var(--color-panel-alt);
  border-radius: var(--radius-lg);
  margin-bottom: 2rem;
  padding: 2rem 1.5rem;
}

.card-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: 1.8rem;
  margin-top: 2rem;
}

.card {
  background: var(--color-panel);
  padding: 2rem;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-md);
  transition: var(--transition);
}

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

.btn {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 1rem;
  background: var(--color-primary);
  color: #fff;
  padding: 0.8rem 1.5rem;
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: var(--transition);
  box-shadow: 0 3px 10px rgba(0,0,0,0.1);
}

.btn:hover {
  background: var(--color-primary-light);
  transform: translateY(-2px);
}

.btn i {
  font-size: 1.2rem;
}

.top-banner {
  background: rgb(240,253,255);
  color: #333;
  text-align: center;
  padding: 0.5rem;
  font-size: 1rem;
}

.top-banner u {
  text-decoration: underline;
}

hr.style-four {
  height: 12px;
  border: 0;
  box-shadow: inset 0 12px 12px -12px rgba(0,0,0,0.5);
}

footer {
  text-align: center;
  padding: 3rem 2rem;
  background: var(--color-footer-bg);
  color: var(--color-footer-text);
  border-top: 4px solid var(--color-accent);
}

footer nav a {
  color: var(--color-accent);
  margin: 0 0.5rem;
}

footer nav a:hover {
  text-decoration: underline;
}

.rentner-banner {
    position: fixed;
    top: 60px;
    left: 50%;
    transform: translateX(-50%);
    max-width: 640px;
    width: calc(100% - 32px);
    background: #f5f6f7;
    color: #1f1f1f;
    border: 1px solid #d6dbe0;
    border-radius: 14px;
    padding: 22px 24px 26px;
    box-shadow: 0 8px 24px rgba(0,0,0,0.12);
    z-index: 9999;
    text-align: center;
    font-size: 1rem;
}

.rentner-banner h2 {
    margin: 0 0 10px;
    font-size: 1.45rem;
    font-weight: 600;
}

.rentner-banner p {
    margin: 0 0 18px;
    line-height: 1.5;
}

.rentner-mail-btn {
    display: inline-block;
    padding: 10px 20px;
    border-radius: 999px;
    background: #1e2f45;
    color: #ffffff;
    text-decoration: none;
    font-weight: 500;
    transition: background 0.2s ease, transform 0.1s ease;
}

.rentner-mail-btn:hover {
    background: #243a55;
    transform: translateY(-1px);
}

.rentner-close {
    position: absolute;
    top: 10px;
    right: 14px;
    background: none;
    border: none;
    font-size: 1.5rem;
    color: #666;
    cursor: pointer;
}

.rentner-close:hover {
    color: #000;
}

@media (max-width: 1024px) {
  .hero h1 {
    font-size: 2.5rem;
  }
}

@media (max-width: 768px) {
  #nav-links {
    display: none;
    flex-direction: column;
    background: #fff;
    position: absolute;
    top: 70px;
    right: 0;
    width: 220px;
    padding: 1rem;
    box-shadow: var(--shadow-md);
  }

  #nav-links.show {
    display: flex;
  }

  .hamburger {
    display: flex;
  }

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

  .hero h1 {
    font-size: 2.2rem;
  }

  .hero p {
    font-size: 1rem;
  }
}