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

html,
body {
  width: 100%;
  height: 100%;
  font-family: "Yu Gothic", "Hiragino Kaku Gothic ProN", "Meiryo", sans-serif;
  overflow: hidden;
}

body {
  position: relative;
  background: #000;
  color: #fff;
}

.slideshow {
  position: fixed;
  inset: 0;
  z-index: 0;
}

.slide {
  position: absolute;
  inset: 0;
  background-size: cover;
  background-position: center;
  opacity: 0;
  animation: fadeSlide 24s infinite;
  transform: scale(1.05);
}

.slide::before {
  content: "";
  position: absolute;
  inset: 0;
  background:
    repeating-linear-gradient(
      45deg,
      rgba(0, 0, 0, 0.15),
      rgba(0, 0, 0, 0.15) 2px,
      rgba(0, 0, 0, 0.25) 2px,
      rgba(0, 0, 0, 0.25) 4px
    ),
    rgba(0, 0, 0, 0.35);
}

.slide1 {
  background-image: url("../images/slide1.jpg");
  animation-delay: 0s;
}

.slide2 {
  background-image: url("../images/slide2.jpg");
  animation-delay: 8s;
}

.slide3 {
  background-image: url("../images/slide3.jpg");
  animation-delay: 16s;
}

@keyframes fadeSlide {
  0%   { opacity: 0; }
  8%   { opacity: 1; }
  30%  { opacity: 1; }
  38%  { opacity: 0; }
  100% { opacity: 0; }
}

.content {
  position: relative;
  z-index: 1;
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  text-align: center;
  padding: 20px;
}

.message {
  text-shadow: 0 2px 10px rgba(0, 0, 0, 0.5);
}

.message h1 {
  font-size: clamp(2rem, 5vw, 4rem);
  font-weight: 700;
  letter-spacing: 0.08em;
  margin-bottom: 16px;
}

.message p {
  font-size: clamp(0.9rem, 1.5vw, 1.2rem);
  letter-spacing: 0.05em;
  opacity: 0.9;
}