/* CSS Reset */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  line-height: 1;
  color: var(--color-deep-black);
  font-family: var(--font-primary);
  overflow-x: hidden;
}

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

ul, ol {
  list-style: none;
}

img {
  max-width: 100%;
  height: auto;
  display: block;
  
  /* 이미지 최적화 */
  content-visibility: auto;
  contain-intrinsic-size: 500px 300px;
  
  /* 지연 로딩 이미지의 부드러운 전환 */
  transition: opacity var(--duration-fast) var(--ease-smooth);
}

img[loading="lazy"] {
  opacity: 0;
}

img[loading="lazy"].loaded,
img[loading="eager"] {
  opacity: 1;
}

button {
  border: none;
  background: none;
  cursor: pointer;
  font-family: inherit;
  transition: var(--transition-default);
}

input, textarea, select {
  font-family: inherit;
  border: none;
  outline: none;
}

h1, h2, h3, h4, h5, h6 {
  font-weight: var(--weight-medium);
  line-height: var(--line-height-tight);
  letter-spacing: var(--letter-spacing-tight);
}

p {
  line-height: var(--line-height-normal);
}

::selection {
  background-color: var(--color-focus);
  color: var(--color-deep-black);
}