/* ================================================
   BASE — Reset, typography, global elements
   ================================================ */

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

html {
  font-size: 100%;
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-sans);
  font-weight: var(--font-weight-normal);
  font-size: 1rem;
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

/* Japanese text fallback */
:lang(ja) {
  font-family: var(--font-jp);
  line-height: 1.8;
}

/* ---- Headings ---- */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-sans);
  font-weight: var(--font-weight-medium);
  color: var(--color-heading);
  line-height: 1.3;
  letter-spacing: 0.02em;
}

h1 { font-size: clamp(2rem, 4vw, 3rem); }
h2 { font-size: clamp(1.5rem, 3vw, 2.25rem); }
h3 { font-size: clamp(1.25rem, 2.5vw, 1.75rem); }
h4 { font-size: clamp(1.125rem, 2vw, 1.375rem); }

h1 + *, h2 + *, h3 + *, h4 + * {
  margin-top: var(--space-sm);
}

/* ---- Body text ---- */
p {
  max-width: 65ch;
}

p + p {
  margin-top: var(--space-sm);
}

/* ---- Links ---- */
a {
  color: var(--color-link);
  text-decoration: none;
  transition: color var(--transition-fast);
}

a:hover {
  color: var(--color-link-hover);
}

/* ---- Images ---- */
img {
  max-width: 100%;
  height: auto;
  display: block;
}

/* ---- Lists ---- */
ul, ol {
  padding-left: 1.25em;
}

li + li {
  margin-top: 0.25em;
}

/* ---- Selection ---- */
::selection {
  background-color: var(--color-indigo);
  color: var(--color-cream);
}

/* ---- Focus ---- */
:focus-visible {
  outline: 2px solid var(--color-indigo);
  outline-offset: 2px;
}

/* ---- Utility: screen reader only ---- */
.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* ---- Container ---- */
.container {
  width: 100%;
  max-width: var(--max-width);
  margin-inline: auto;
  padding-inline: var(--gutter);
}

.container--narrow {
  max-width: var(--max-width-narrow);
}

.container--wide {
  max-width: var(--max-width-wide);
}

/* ---- Section spacing ---- */
.section {
  padding-block: var(--space-3xl);
}

@media (max-width: 768px) {
  .section {
    padding-block: var(--space-2xl);
  }
}