:root {
  color-scheme: light dark;
  --paper: #F7F9FC;
  --grid: #DDE7F2;
  --ink: #1F2A44;
  --ink-soft: #56617A;
  --card: #FFFFFF;
  --line: #C9D5E3;
  --pink: #FF6FA8;
  --mint: #2FBF97;
  --yellow: #FFC23C;
  --sky: #4D9BFF;
  --lilac: #9B7BFF;
  --coral: #FF8A5C;
  --teal: #20B2C8;
  --sticker-edge: #FFFFFF;
  --shadow: 0 3px 0 rgba(31, 42, 68, .10), 0 8px 18px rgba(31, 42, 68, .12);

  --font-body: "Noto Sans JP", "Hiragino Sans", "Hiragino Kaku Gothic ProN", "Yu Gothic", Meiryo, sans-serif;
  --font-round: "Zen Maru Gothic", "Hiragino Maru Gothic ProN", "Noto Sans JP", sans-serif;
}

@media (prefers-color-scheme: dark) {
  :root:not([data-theme="light"]) {
    --paper: #141B2B;
    --grid: #212C42;
    --ink: #EEF2F8;
    --ink-soft: #A7B2C6;
    --card: #1C2538;
    --line: #2F3B55;
    --sticker-edge: #F4F6FA;
    --shadow: 0 3px 0 rgba(0, 0, 0, .35), 0 8px 18px rgba(0, 0, 0, .35);
  }
}

:root[data-theme="dark"] {
  --paper: #141B2B;
  --grid: #212C42;
  --ink: #EEF2F8;
  --ink-soft: #A7B2C6;
  --card: #1C2538;
  --line: #2F3B55;
  --sticker-edge: #F4F6FA;
  --shadow: 0 3px 0 rgba(0, 0, 0, .35), 0 8px 18px rgba(0, 0, 0, .35);
}

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

html {
  -webkit-text-size-adjust: 100%;
}

/* 方眼紙 */
body {
  margin: 0;
  background-color: var(--paper);
  background-image:
    linear-gradient(to right, var(--grid) 1px, transparent 1px),
    linear-gradient(to bottom, var(--grid) 1px, transparent 1px);
  background-size: 24px 24px;
  color: var(--ink);
  font-family: var(--font-body);
  font-size: 15px;
  line-height: 1.75;
  overflow-x: hidden;
}

/* リング綴じ */
body::before {
  content: "";
  position: fixed;
  inset: 0 auto 0 0;
  width: 34px;
  border-right: 2px dashed var(--line);
  background-image: radial-gradient(circle at 50% 22px, var(--paper) 0 5px, var(--line) 5px 7.5px, transparent 7.5px);
  background-size: 34px 44px;
  background-repeat: repeat-y;
  pointer-events: none;
  z-index: 1;
}

img {
  max-width: 100%;
  height: auto;
}

a {
  color: var(--ink);
  text-decoration-color: var(--sky);
  text-decoration-thickness: 2px;
  text-underline-offset: .2em;
}

:focus-visible {
  outline: 3px solid var(--sky);
  outline-offset: 2px;
}

h1,
h2,
h3 {
  font-family: var(--font-round);
  font-weight: 900;
  line-height: 1.35;
}

h1 {
  font-size: clamp(28px, 4.2vw, 44px);
  margin: 16px 0 16px;
}

h2 {
  font-size: 22px;
  margin: 0 0 20px;
}

h3 {
  font-size: 17px;
  margin: 0 0 8px;
}

.skip-link {
  position: absolute;
  left: 44px;
  top: -100px;
  padding: 8px 14px;
  background: var(--ink);
  color: var(--paper);
  border-radius: 6px;
  z-index: 10;
}

.skip-link:focus {
  top: 8px;
}

/* 紙面のレイアウト */
body > header,
body > main,
body > footer {
  max-width: 1180px;
  margin: 0 auto;
  padding-left: 58px;
  padding-right: 24px;
}

body > header {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: space-between;
  gap: 8px 20px;
  padding-top: 20px;
}

body > main {
  padding-top: 48px;
  padding-bottom: 80px;
}

body > footer {
  padding-top: 20px;
  padding-bottom: 40px;
  border-top: 1px dashed var(--line);
  color: var(--ink-soft);
  font-size: 12.5px;
}

main > section {
  margin: 0 0 72px;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  font-family: var(--font-round);
  font-weight: 900;
  font-size: 18px;
  text-decoration: none;
}

.brand img {
  width: 32px;
  height: 32px;
}

.site-nav ul,
.footer-links {
  display: flex;
  flex-wrap: wrap;
  gap: 4px 18px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.site-nav a[aria-current="page"] {
  font-weight: 700;
  text-decoration: none;
}

.footer-links {
  margin-bottom: 8px;
  font-size: 13px;
}

/* ステッカー原型 */
.sticker {
  display: inline-block;
  background: var(--c, var(--pink));
  color: var(--fg, #fff);
  border: 5px solid var(--sticker-edge);
  border-radius: 16px;
  box-shadow: var(--shadow);
  font-family: var(--font-round);
  font-weight: 900;
  line-height: 1.35;
  padding: 6px 16px;
  transform: rotate(var(--r, -2deg));
  text-shadow: 0 1px 0 rgba(31, 42, 68, .18);
}

.sticker-label {
  margin: 0;
  font-size: 14px;
}

/* 黄色など明るい色のステッカーは、白文字だと読めないので濃い文字にする */
.sticker.is-light {
  --fg: #1F2A44;
  text-shadow: none;
}

/* カード（角は固い6px） */
.card {
  position: relative;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: var(--shadow);
  padding: 24px;
}

.tilt {
  transform: rotate(1deg);
}

.taped::before {
  content: "";
  position: absolute;
  top: -12px;
  left: 50%;
  width: 90px;
  height: 24px;
  margin-left: -45px;
  background: color-mix(in srgb, var(--yellow) 55%, transparent);
  transform: rotate(-3deg);
}

.note,
.meta {
  color: var(--ink-soft);
  font-size: 13.5px;
}

.lead {
  max-width: 62ch;
  font-size: 17px;
  color: var(--ink-soft);
  margin: 0 0 24px;
}

.sticker-label + .lead {
  margin-top: 24px;
}

.divider {
  border: 0;
  border-top: 1px dashed var(--line);
  margin: 16px 0;
}

.button {
  display: inline-block;
  padding: 10px 22px;
  background: var(--ink);
  color: var(--paper);
  border: 5px solid var(--sticker-edge);
  border-radius: 16px;
  box-shadow: var(--shadow);
  font: 900 16px/1.4 var(--font-round);
  text-decoration: none;
  cursor: pointer;
}

/* App Store バッジ（公式の画像なので加工しない） */
.app-store-badge {
  display: inline-block;
  line-height: 0;
}

.app-store-badge img {
  height: 48px;
  width: auto;
}

/* ヒーロー */
.hero {
  display: grid;
  grid-template-columns: minmax(0, 1fr) auto;
  align-items: center;
  gap: 32px;
}

.hero-icon {
  width: 160px;
  filter: drop-shadow(0 8px 16px rgba(31, 42, 68, .2));
  transform: rotate(4deg);
}

/* できること */
.features {
  display: grid;
  grid-template-columns: repeat(4, minmax(0, 1fr));
  gap: 28px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.features h3 {
  margin: 0 0 16px;
}

.features p {
  margin: 0;
}

/* スクリーンショット */
.screenshots {
  display: grid;
  grid-template-columns: repeat(3, minmax(0, 200px));
  gap: 20px;
  margin: 0;
  padding: 0;
  list-style: none;
}

.screenshot-placeholder {
  display: grid;
  place-items: center;
  aspect-ratio: 9 / 19.5;
  border: 2px dashed var(--line);
  border-radius: 28px;
  background: var(--card);
  color: var(--ink-soft);
  font-size: 13.5px;
  text-align: center;
  padding: 8px;
}

.facts {
  margin: 0;
  padding-left: 1.2em;
}

/* 表 */
.table-wrap {
  overflow-x: auto;
}

table {
  width: 100%;
  border-collapse: collapse;
  background: var(--card);
}

th,
td {
  text-align: left;
  vertical-align: top;
  padding: 10px 12px;
  border: 1px solid var(--line);
}

/* 本文ページ（サポート・プライバシー） */
.prose > * {
  max-width: 760px;
}

.prose h2 {
  margin-top: 48px;
}

/* FAQ */
.faq details {
  margin: 14px 0;
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 6px;
  box-shadow: var(--shadow);
}

.faq summary {
  padding: 14px 18px;
  font-family: var(--font-round);
  font-weight: 900;
  cursor: pointer;
}

.faq details > div {
  padding: 0 18px 14px;
  border-top: 1px dashed var(--line);
}

/* フォーム */
.contact-form {
  display: grid;
  gap: 18px;
  max-width: 560px;
}

.field {
  display: grid;
  gap: 4px;
}

.field label {
  font-weight: 700;
}

.field .note {
  font-weight: 400;
}

fieldset.field {
  margin: 0;
  padding: 0;
  border: 0;
}

fieldset.field legend {
  padding: 0;
  font-weight: 700;
}

fieldset.field label {
  font-weight: 400;
}

input:not([type="radio"]),
textarea {
  width: 100%;
  padding: 10px 12px;
  border: 1px solid var(--line);
  border-radius: 6px;
  background: var(--card);
  color: var(--ink);
  font: inherit;
}

textarea {
  min-height: 160px;
  resize: vertical;
}

.visually-hidden {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0 0 0 0);
  white-space: nowrap;
}

@media (max-width: 820px) {
  .hero,
  .features {
    grid-template-columns: minmax(0, 1fr);
  }

  .screenshots {
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 12px;
  }

  .hero-icon {
    width: 112px;
    grid-row: 1;
  }

  body > header,
  body > main,
  body > footer {
    padding-left: 50px;
    padding-right: 16px;
  }

  body > main {
    padding-top: 32px;
  }
}

/* ステッカーが「ぺりっと」貼られる */
@media (prefers-reduced-motion: no-preference) {
  .sticker {
    animation: stick .55s cubic-bezier(.2, 1.4, .4, 1) both;
    animation-delay: calc(var(--i, 0) * 70ms);
  }

  @keyframes stick {
    from {
      opacity: 0;
      transform: translateY(10px) scale(.92) rotate(var(--r, -2deg));
    }

    to {
      opacity: 1;
      transform: rotate(var(--r, -2deg));
    }
  }
}