/* Reset */
* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --bg: #222222;
  --text: white;
  --accent: #0b3d91;
  --header-bg: rgba(0,0,0,0.5);
  --header-text: white;
}

/* Base */
body {
  font-family: "Segoe UI", sans-serif;
  background-color: var(--bg);
  color: var(--text);
  line-height: 1.6;
  padding-top: 70px; /* espace pour header fixe */
}

/* Header fixe */
header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background-color: var(--header-bg);
  color: var(--header-text);
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1em 2em;
  flex-wrap: wrap;
  z-index: 1000; /* toujours au-dessus */
  backdrop-filter: blur(5px);
  box-shadow: 0 2px 10px rgba(0,0,0,0.7);
}

header h1 {
  font-family: 'Pacifico', cursive;
  font-size: 1.8em;
}

header h1 a {
  color: var(--header-text);
  text-decoration: none;
}

nav {
  display: flex;
  flex-wrap: wrap;
}

nav a {
  color: var(--header-text);
  margin: 0 1em;
  text-decoration: none;
  font-weight: bold;
  transition: color 0.3s;
}

nav a:hover {
  color: var(--accent);
}

/* Vidéo en fond */
#bg-video {
  position: fixed;   /* reste derrière tout */
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  object-fit: cover;
  z-index: -1;
  filter: brightness(0.6); /* texte lisible */
}

/* Contenu au-dessus de la vidéo */
body, section, footer {
  position: relative;
  z-index: 1;
}

/* Sections portfolio */
.portfolio-section {
  display: flex;
  gap: 2rem;
  padding: 4em 2em 3em;
  max-width: 1100px;
  margin: 0 auto 3em;
  align-items: flex-start;
  flex-wrap: wrap;
  background: linear-gradient(135deg, #1a1a1a, #111111);
  border-radius: 15px;
  box-shadow: 0 10px 30px rgba(0,0,0,0.7);
}

.bubble {
  background: #333333;
  padding: 2rem;
  border-radius: 15px;
  flex: 1 1 45%;
  box-shadow: 0 5px 15px rgba(0,0,0,0.5);
  color: #ddd;
  display: flex;
  flex-direction: column;
  justify-content: center;
  transition: transform 0.3s ease;
}

.bubble:hover {
  transform: translateY(-5px);
  box-shadow: 0 15px 30px rgba(11, 61, 145, 0.7);
}

.bubble.text-content h3 {
  font-size: 1.4rem;
  color: var(--accent);
  margin-bottom: 0.3rem;
  text-transform: uppercase;
  letter-spacing: 1.2px;
}

.bubble.text-content h2 {
  font-size: 2rem;
  margin-bottom: 1rem;
  color: white;
}

.bubble.text-content h4 {
  font-size: 1.4rem;
  margin: 0.5rem 0;
  color: white;
  font-weight: bold;
  letter-spacing: 1px;
  padding-left: 0.5rem;
  text-transform: uppercase;
}

.bubble.text-content p,
.bubble.text-content ul {
  font-size: 1rem;
  line-height: 1.5;
  color: #ccc;
}

.bubble.text-content ul {
  margin-left: 1.2rem;
  margin-bottom: 1rem;
}

.bubble.text-content ul li {
  margin-bottom: 0.4rem;
  list-style-type: square;
  color: #bbb;
}

/* Retour bouton */
.back-button-container {
  text-align: center;
  margin-bottom: 4rem;
}

.back-button {
  display: inline-block;
  padding: 0.7em 1.5em;
  background-color: var(--accent);
  color: white;
  text-decoration: none;
  font-weight: bold;
  border-radius: 40px;
  box-shadow: 0 5px 15px rgba(11, 61, 145, 0.6);
  transition: background-color 0.3s ease, box-shadow 0.3s ease;
}

.back-button:hover {
  background-color: #06407b;
  box-shadow: 0 8px 25px rgba(11, 61, 145, 0.9);
}

/* Footer */
footer {
  background: var(--header-bg);
  color: var(--header-text);
  padding: 2em 1em;
  text-align: center;
  font-size: 0.9rem;
  border-top: 1px solid var(--accent);
}

/* Responsive */
@media (max-width: 900px) {
  .portfolio-section {
    flex-direction: column;
    padding: 4em 1em 2em;
  }

  .bubble {
    flex: 1 1 100%;
    margin-bottom: 2rem;
  }

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

@media (max-width: 400px) {
  .bubble.text-content h2 {
    font-size: 1.5rem;
  }

  .bubble.text-content h3 {
    font-size: 1.1rem;
  }

  .bubble.text-content h4 {
    font-size: 1rem;
  }
}