/* --- Allgemeines Layout --- */
body {
    font-family: Arial, sans-serif;
    margin: 0;
    padding: 0;
    color: #fff; 
    background-color: #001a33; 
}

header {
    background: linear-gradient(to bottom, #0e3569 0%, #082a52 45%, #001a33 100%);
    color: white;
    display: flex;               
    align-items: center;         
    justify-content: space-between; 
    padding: 1.5em 2em;
}

header h1 {
    margin: 0;
    font-size: 1.8em;
    font-weight: bold;
}

header nav {
    display: flex;
    gap: 1.5em;
}

header nav ul {
    list-style: none;
    margin: 0;
    padding: 0;
    display: flex;
    gap: 1.5em;
}

header nav a {
    color: #d0e7ff;
    text-decoration: none;
    font-weight: 500;
}

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

header nav a[aria-disabled="true"] {
    color: #7a7a7a;
    pointer-events: none;
    cursor: not-allowed;
    text-decoration: none;
}

footer {
    background: linear-gradient(to bottom, #0e3569 0%, #082a52 45%, #001a33 100%);
    color: white;
    text-align: center;
    padding: 1.5em 1em;
}

footer p {
    margin: 0.2em 0;
}

main {
    padding: 2em;
    background-color: #f9fbfc;
    color: #222;
}

/* --- Definition der Formulare und Buttons --- */
button,
input,
select {
    font-size: 1em;
    padding: 0.5em;
    border-radius: 4px;
}

button {
    background-color: #006699;
    color: white;
    border: none;
    cursor: pointer;
}

button:hover {
    background-color: #004d66;
}

/* --- Spezielle Ansicht für Deepsea Farbverlauf --- */
body.deepsea {
    background: linear-gradient(to bottom, #4da6ff 0%, #003366 40%, #001a33 70%, #000814 100%);
    color: white;
    background-attachment: fixed;
    background-repeat: no-repeat;
    background-size: cover;
}

body.deepsea main {
    background: transparent;
    color: #f0f8ff;
}

img {
  width: 400px;
  height: 300px;
  object-fit: cover; 
}

.hidden {
  display: none;
}

/* --- Unterwasser-Background-Effekt --- */
body.underwater {
  position: relative;
  overflow-x: hidden;
  background: radial-gradient(circle at 20% 0, #39a9ff 0, #005081 40%, #001a33 75%, #000814 100%);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
}

body.underwater header {
    background: inherit; /* egal, was vorher war – übernehmen */
    background: linear-gradient(to bottom, #0e3569, #082a52 45%, #001a33) !important;
    position: relative;
    z-index: 5;
}

body.underwater main {
  background: transparent;
  color: #f0f8ff;  
  flex: 1;
}

body.underwater footer {
  position: relative;
  z-index: 1;
}

body.underwater::before {
  content: "";
  position: fixed;
  inset: 0;
  background: radial-gradient(circle at 10% -10%, rgba(255,255,255,0.18), transparent 60%);
  mix-blend-mode: screen;
  opacity: 0.5;
  pointer-events: none;
  animation: rays 10s ease-in-out infinite alternate;
  z-index: 0;
}

.underwater-bubbles {
  position: fixed;
  inset: 0;
  overflow: hidden;
  pointer-events: none;
  z-index: 0;
}

.underwater-bubble {
  position: absolute;
  bottom: -100px;
  border-radius: 50%;
  background: radial-gradient(circle at 30% 30%, rgba(255,255,255,0.9), rgba(255,255,255,0.1));
  opacity: 0.7;
  animation-name: bubble-rise;
  animation-timing-function: linear;
  animation-iteration-count: infinite;
}

@keyframes bubble-rise {
  from {
    transform: translateY(0) translateX(0);
  }
  to {
    transform: translateY(-120vh) translateX(-20px);
  }
}

@keyframes rays {
  from {
    transform: translate3d(-10px, 0, 0) rotate(-1deg);
    opacity: 0.4;
  }
  to {
    transform: translate3d(10px, 5px, 0) rotate(1deg);
    opacity: 0.7;
  }
}