/* ===== ОСНОВНОЙ СТИЛЬ ===== */
.header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 1rem 4rem;
  background: #ffffff;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.06);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.logo-img {
  width: 100px;
  height: 74px;
}

.nav {
  display: flex;
  gap: 2rem;
  position: absolute;
  left: 50%;
  transform: translateX(-50%);
}

.nav a {
  text-decoration: none;
  font-size: 1rem;
  font-weight: 500;
  color: #333;
  transition: color 0.3s ease;
}

.night-theme nav a {
  color: white !important;
}

.nav a:hover {
  color: blue;
}

.night-theme nav a:hover {
  color: blue !important;
}

.btn {
  padding: 0.6rem 1.2rem;
  background: #0077ff;
  color: #fff;
  text-decoration: none;
  border-radius: 50px;
  font-size: 0.9rem;
  font-weight: 600;
  transition: all 0.3s ease;
}

.btn:hover {
  background: #005fcc;
  transform: translateY(-2px);
  box-shadow: 0 4px 12px rgba(0, 119, 255, 0.3);
}

/* ===== БУРГЕР ===== */
.burger {
  display: none;
  flex-direction: column;
  justify-content: space-between;
  width: 25px;
  height: 18px;
  cursor: pointer;
  z-index: 1100;
}

.burger span {
  display: block;
  height: 3px;
  background: #333;
  border-radius: 5px;
  transition: all 0.3s ease;
}

/* ===== АДАПТИВ ===== */
@media (max-width: 768px) {
  .burger {
    display: flex;
  }

  /* Прячем кнопку отдельно */
  .btn {
    display: none;
  }

  .header {
    padding: 1rem 2rem;
  }
  /* Навигация превращается в мобильное меню */
  .nav {
    position: fixed;
    top: 0;
    left: 0;
    height: 100vh;
    width: 100%;
    background: rgba(255, 255, 255, 0.98);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 1.5rem;
    transform: translateY(-100%);
    opacity: 0;
    pointer-events: none;
    transition: all 0.3s ease;
  }

  .nav.active {
    transform: translateY(0);
    opacity: 1;
    pointer-events: auto;
  }

  body.night-theme .nav {
    background: #0f172a;
  }

  /* Кнопка появится внутри меню */
  .nav.active::after {
    content: "Sign Up";
    display: inline-block;
    margin-top: 1.5rem;
    padding: 0.6rem 1.2rem;
    background: #0077ff;
    color: white;
    font-weight: 600;
    border-radius: 50px;
    cursor: pointer;
    transition: background 0.3s ease;
  }

  .nav.active::after:hover {
    background: #005fcc;
  }

  /* Анимация бургер-меню */
  .burger.active span:nth-child(1) {
    transform: rotate(45deg) translateY(7px);
  }

  .burger.active span:nth-child(2) {
    opacity: 0;
  }

  .burger.active span:nth-child(3) {
    transform: rotate(-45deg) translateY(-7px);
  }
}