:root {
  --paper: #f4eee2;
  --paper-deep: #ebe2d0;
  --ink: #1d1a16;
  --ink-soft: #5c554b;
  --rule: #1d1a1633;

  --chap-bg: #fbe08a;
  --chap-accent: #f07a1a;
  --miro-bg: #2f5d3a;
  --miro-ink: #f3efe2;
  --miro-accent: #f2c14e;

  --font-display: "Noto Serif KR", serif;
  --font-body: "IBM Plex Sans KR", system-ui, sans-serif;

  --text-base: clamp(1rem, 0.94rem + 0.3vw, 1.125rem);
  --text-hero: clamp(3rem, 1.2rem + 7.5vw, 8.5rem);
  --text-app: clamp(2.75rem, 1.5rem + 5vw, 6rem);

  --gutter: clamp(1rem, 0.5rem + 3vw, 3.5rem);
  --space-section: clamp(4.5rem, 3rem + 6vw, 10rem);

  --duration-normal: 300ms;
  --ease-out-expo: cubic-bezier(0.16, 1, 0.3, 1);
}

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

body {
  background: var(--paper);
  color: var(--ink);
  font: 400 var(--text-base)/1.7 var(--font-body);
  word-break: keep-all;
  overflow-x: hidden;
  /* paper grain */
  background-image: radial-gradient(#1d1a160d 1px, transparent 1px);
  background-size: 4px 4px;
}

a { color: inherit; }
img { display: block; max-width: 100%; height: auto; }
:focus-visible { outline: 3px solid var(--chap-accent); outline-offset: 3px; }

.eyebrow {
  font-size: 0.75rem;
  font-weight: 500;
  letter-spacing: 0.18em;
  text-transform: uppercase;
  color: var(--ink-soft);
}

/* masthead */
.masthead {
  display: flex;
  justify-content: space-between;
  align-items: baseline;
  gap: 1rem;
  padding: 1.25rem var(--gutter);
  border-bottom: 1px solid var(--rule);
}
.wordmark {
  font: 900 1.25rem/1 var(--font-display);
  text-decoration: none;
}
.wordmark span {
  margin-left: 0.5rem;
  font: 500 0.75rem/1 var(--font-body);
  letter-spacing: 0.12em;
  text-transform: uppercase;
  color: var(--ink-soft);
}
.masthead nav { display: flex; gap: clamp(0.75rem, 2vw, 2rem); font-size: 0.9rem; }
.masthead nav a { text-decoration: none; background: linear-gradient(currentColor, currentColor) 0 100% / 0 1px no-repeat; transition: background-size var(--duration-normal) var(--ease-out-expo); }
.masthead nav a:hover { background-size: 100% 1px; }

/* hero */
.hero {
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 1.5rem var(--gutter);
  padding: var(--space-section) var(--gutter) calc(var(--space-section) * 0.7);
}
.hero .eyebrow { grid-column: 1 / -1; }
.hero h1 {
  grid-column: 1 / -1;
  font: 900 var(--text-hero)/1.02 var(--font-display);
  letter-spacing: -0.03em;
  animation: rise 900ms var(--ease-out-expo) both;
}
.lede { grid-column: 1 / span 5; max-width: 32ch; color: var(--ink-soft); align-self: end; }
.index { grid-column: 7 / -1; list-style: none; padding: 0; border-top: 2px solid var(--ink); align-self: end; }
.index li { border-bottom: 1px solid var(--rule); }
.index a {
  display: flex;
  align-items: baseline;
  gap: 1rem;
  padding: 1rem 0;
  font: 700 clamp(1.25rem, 1rem + 1vw, 1.75rem)/1.2 var(--font-display);
  text-decoration: none;
  transition: transform var(--duration-normal) var(--ease-out-expo);
}
.index a:hover { transform: translateX(0.5rem); }
.index span { font: 500 0.8rem var(--font-body); color: var(--ink-soft); }
.index em { margin-left: auto; font: 400 0.85rem var(--font-body); font-style: normal; color: var(--ink-soft); }

/* app sections */
.app {
  display: grid;
  grid-template-columns: minmax(0, 5fr) minmax(0, 7fr);
  gap: var(--gutter);
  align-items: center;
  padding: var(--space-section) var(--gutter);
  overflow: hidden;
}
.app--chap { background: var(--chap-bg); }
.app--miro { background: var(--miro-bg); color: var(--miro-ink); grid-template-columns: minmax(0, 7fr) minmax(0, 5fr); }
.app--miro .app__copy { order: 2; }

.app__no { font-size: 0.8rem; font-weight: 500; letter-spacing: 0.08em; opacity: 0.7; }
.app__icon { width: 96px; height: 96px; margin: 1.5rem 0 1rem; border-radius: 22%; box-shadow: 0 10px 24px -10px #0006; }
.app h2 { font: 900 var(--text-app)/1 var(--font-display); letter-spacing: -0.03em; }
.app__tagline { margin: 0.5rem 0 1.25rem; font: 700 clamp(1.1rem, 1rem + 0.6vw, 1.5rem)/1.4 var(--font-display); }
.app__copy > p:not([class]) { max-width: 38ch; }

.facts { list-style: none; padding: 0; margin: 2rem 0; border-top: 1px solid currentColor; }
.facts li { padding: 0.9rem 0; border-bottom: 1px solid color-mix(in srgb, currentColor 25%, transparent); font-size: 0.92rem; }
.facts strong { display: block; font-weight: 700; }

.store {
  display: inline-flex;
  gap: 0.5rem;
  padding: 0.9rem 1.4rem;
  font-weight: 700;
  text-decoration: none;
  background: var(--ink);
  color: var(--paper);
  transition: transform var(--duration-normal) var(--ease-out-expo), box-shadow var(--duration-normal) var(--ease-out-expo);
}
.store:hover { transform: translate(-3px, -3px); box-shadow: 3px 3px 0 var(--chap-accent); }
.store:active { transform: translate(0, 0); box-shadow: none; }
.app--miro .store { background: var(--miro-accent); color: var(--ink); }
.app--miro .store:hover { box-shadow: 3px 3px 0 var(--miro-ink); }

/* overlapping phone stack */
.app__shots { position: relative; display: grid; grid-template-columns: repeat(3, 1fr); align-items: start; }
.app__shots img {
  width: 135%;
  border-radius: 1.6rem;
  border: 6px solid var(--ink);
  box-shadow: 0 30px 50px -25px #000a;
  transition: transform 600ms var(--ease-out-expo);
}
.app__shots img:nth-child(1) { transform: rotate(-4deg) translateY(2rem); z-index: 1; }
.app__shots img:nth-child(2) { transform: translate(-12%, -1rem); z-index: 3; }
.app__shots img:nth-child(3) { transform: rotate(4deg) translate(-24%, 3rem); z-index: 2; }
.app__shots:hover img:nth-child(2) { transform: translate(-12%, -2rem); }

/* next */
.next {
  padding: var(--space-section) var(--gutter);
  display: grid;
  grid-template-columns: repeat(12, 1fr);
  gap: 1rem var(--gutter);
}
.next .eyebrow, .next h2 { grid-column: 1 / -1; }
.next h2 { font: 900 clamp(2rem, 1.4rem + 3vw, 4rem)/1.1 var(--font-display); }
.next p:last-child { grid-column: 5 / -1; max-width: 40ch; font-size: 1.1rem; }

/* footer */
.colophon {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 2rem var(--gutter);
  padding: 3rem var(--gutter);
  background: var(--ink);
  color: var(--paper);
}
.colophon .eyebrow { color: #f4eee299; }
.mail { display: inline-block; margin-top: 0.5rem; font: 700 clamp(1.25rem, 1rem + 1.5vw, 2rem)/1.2 var(--font-display); }
.biz { display: grid; gap: 0.4rem; font-size: 0.85rem; }
.biz div { display: flex; gap: 1rem; }
.biz dt { min-width: 7.5rem; color: #f4eee299; }
.copy { grid-column: 1 / -1; font-size: 0.75rem; color: #f4eee266; }

@keyframes rise {
  from { opacity: 0; transform: translateY(1.5rem); }
  to { opacity: 1; transform: none; }
}

@media (max-width: 820px) {
  .hero, .next { grid-template-columns: minmax(0, 1fr); }
  .lede, .index, .next p:last-child { grid-column: 1 / -1; }
  .app, .app--miro { grid-template-columns: minmax(0, 1fr); }
  .app--miro .app__copy { order: 0; }
  .app__shots { margin-top: 2rem; padding-bottom: 3rem; }
  .colophon { grid-template-columns: 1fr; }
  .masthead .wordmark span { display: none; }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after { animation: none !important; transition: none !important; }
}