:root {
  color-scheme: light;
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.35rem;
  --line-height-tight: 1;
  --line-height-heading: 1.12;
  --line-height-body: 1.65;
  --line-height-control: 1.35;
  --letter-spacing-heading: -0.035em;
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;
  --font-weight-heavy: 800;
  --bg-primary: #f7f7f5;
  --bg-secondary: #ffffff;
  --bg-subtle: #efefec;
  --text-primary: #171816;
  --text-secondary: #62645f;
  --text-inverse: #ffffff;
  --border: #dcded8;
  --border-strong: #bfc2ba;
  --accent: #176b4d;
  --accent-strong: #0f563c;
  --accent-soft: #e3f1eb;
  --focus: #1673c9;
  --status-muted: #74766f;
  --shadow-sm: 0 1px 2px rgb(23 24 22 / 5%);
  --preview-backdrop: #d7d8da;
  --radius-sm: 0.4rem;
  --radius-md: 0.75rem;
  --radius-lg: 1.15rem;
  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.5rem;
  --space-6: 2rem;
  --space-7: 3rem;
  --space-8: 4.5rem;
  --content-width: 72rem;
  --reading-width: 43rem;
  --transition-fast: 150ms ease;
  --transition-theme: 220ms ease;
}

:root[data-resolved-theme="dark"] {
  color-scheme: dark;
  --bg-primary: #111210;
  --bg-secondary: #181a17;
  --bg-subtle: #20221e;
  --text-primary: #f0f1ed;
  --text-secondary: #aaada5;
  --text-inverse: #111210;
  --border: #343730;
  --border-strong: #4b5046;
  --accent: #65c69c;
  --accent-strong: #88d8b5;
  --accent-soft: #19372b;
  --focus: #66b5ff;
  --status-muted: #9b9e96;
  --shadow-sm: 0 1px 2px rgb(0 0 0 / 20%);
  --preview-backdrop: #2b2e29;
}

*, *::before, *::after { box-sizing: border-box; }
html { scroll-behavior: smooth; scroll-padding-top: 6rem; }

body {
  margin: 0;
  min-width: 20rem;
  min-height: 100vh;
  background: var(--bg-primary);
  color: var(--text-primary);
  font-family: var(--font-sans);
  font-size: var(--font-size-base);
  line-height: var(--line-height-body);
  text-rendering: optimizeLegibility;
  transition: background-color var(--transition-theme), color var(--transition-theme);
  overflow-wrap: break-word;
  word-break: normal;
}

body, button, input, select, textarea { font: inherit; }
button, input, select, textarea { color: inherit; }
a { color: inherit; text-decoration-thickness: 0.08em; text-underline-offset: 0.2em; }
img, svg { display: block; max-width: 100%; }
h1, h2, h3, p { margin-block-start: 0; }
h1, h2, h3 { line-height: var(--line-height-heading); letter-spacing: var(--letter-spacing-heading); }
h1 { font-size: clamp(2.65rem, 8vw, 5.8rem); }
h2 { font-size: clamp(2rem, 4vw, 3.25rem); }
h3 { font-size: var(--font-size-lg); letter-spacing: -0.015em; }

html:lang(ko) {
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Apple SD Gothic Neo", "Malgun Gothic", "Noto Sans KR", sans-serif;
  --line-height-heading: 1.2;
  --line-height-body: 1.7;
  --letter-spacing-heading: -0.02em;
}
html:lang(ja) {
  --font-sans: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", "Hiragino Sans", "Yu Gothic UI", "Yu Gothic", Meiryo, "Noto Sans JP", sans-serif;
  --line-height-heading: 1.2;
  --line-height-body: 1.7;
  --letter-spacing-heading: -0.02em;
  line-break: strict;
}
html:lang(ko) :is(h1, h2, h3, .eyebrow, .hero-description, .category-card p, .category-tool p, .tool-intro > p:last-child, .drop-zone h2, .drop-zone p, .section-heading > p, .button, .control-label, .status) { word-break: keep-all; }
::selection { background: var(--accent-soft); }
:focus-visible { outline: 3px solid var(--focus); outline-offset: 3px; }

.container { width: min(calc(100% - 2rem), var(--content-width)); margin-inline: auto; }
.reading-width { max-width: var(--reading-width); }
.section { padding-block: var(--space-8); }
.section--bordered { border-top: 1px solid var(--border); }
.eyebrow { margin-bottom: var(--space-4); color: var(--accent); font-size: var(--font-size-xs); font-weight: var(--font-weight-bold); letter-spacing: 0.13em; line-height: var(--line-height-control); text-transform: uppercase; }
.muted { color: var(--text-secondary); }

.skip-link {
  position: fixed;
  z-index: 100;
  top: var(--space-3);
  left: var(--space-3);
  padding: var(--space-2) var(--space-4);
  transform: translateY(-200%);
  border-radius: var(--radius-sm);
  background: var(--text-primary);
  color: var(--bg-primary);
}

.skip-link:focus { transform: translateY(0); }

@media (max-width: 48rem) {
  :root { --space-7: 2.5rem; --space-8: 3.5rem; }
  .container { width: min(calc(100% - 1.5rem), var(--content-width)); }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    scroll-behavior: auto !important;
    transition-duration: 0.01ms !important;
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
  }
}