@import url("https://fonts.googleapis.com/css2?family=Noto+Sans+JP:wght@400;500;600;700;800&family=Outfit:wght@400;500;600;700&family=Zen+Antique&display=swap");

:root {
  --blue: #086cb5;
  --blue-bright: #0e7cc9;
  --blue-deep: #065a96;
  --blue-ink: #06283f;
  --blue-pale: #eef6fb;
  --blue-tint: #f4f9fc;
  --green: #06c755;
  --green-dark: #05ad4b;
  --text: #10222c;
  --text-soft: #4e6673;
  --text-faint: #7d8f99;
  --paper: #ffffff;
  --rule: rgba(16, 34, 44, 0.12);
  --rule-strong: rgba(16, 34, 44, 0.2);
  --shu: #006aad;
  --shu-bg: #eef6fb;
  --gutter: clamp(20px, 5vw, 40px);
  --shell: min(1120px, 100% - var(--gutter) * 2);
  --header-h: 64px;
  --section-y: clamp(72px, 8.5vw, 124px);
  --block-gap: clamp(32px, 5vw, 72px);
  --fs-display: clamp(26px, min(7.2vw, 8.4vh), 52px);
  --fs-h2: clamp(25px, 3.5vw, 42px);
  --fs-h3: clamp(17px, 1.6vw, 21px);
  --fs-body: clamp(14px, 1.05vw, 15.5px);
  --fs-small: clamp(12px, 0.95vw, 13px);
  --fs-micro: 11px;
  --serif: "Zen Antique", "Noto Serif JP", serif;
  --sans: "Noto Sans JP", system-ui, sans-serif;
  --mono-ui: "Outfit", "Noto Sans JP", sans-serif;
  --shadow-card: 0 14px 34px rgba(6, 40, 63, 0.08);
  --shadow-cta: 0 10px 24px rgba(5, 173, 75, 0.28);
}

@media (min-width: 901px) {
  :root {
    --header-h: 76px;
  }
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: calc(var(--header-h) + 16px);
  -webkit-text-size-adjust: 100%;
}

body {
  margin: 0;
  background: var(--paper);
  color: var(--text);
  font-family: var(--sans);
  font-size: var(--fs-body);
  line-height: 1.95;
  -webkit-font-smoothing: antialiased;
}

img,
svg,
canvas {
  display: block;
  max-width: 100%;
}

a {
  color: inherit;
  text-decoration: none;
}

button {
  border: 0;
  background: none;
  cursor: pointer;
}

button,
a,
input,
textarea {
  font: inherit;
}

h1,
h2,
h3 {
  margin: 0;
  font-weight: 400;
  letter-spacing: 0.03em;
}

p {
  margin: 0;
}

ul {
  margin: 0;
  padding: 0;
  list-style: none;
}

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

.content-frame {
  width: var(--shell);
  margin-inline: auto;
  position: relative;
  z-index: 2;
}

section {
  position: relative;
}

.eyebrow {
  display: flex;
  align-items: center;
  gap: 9px;
  margin: 0 0 18px;
  color: var(--blue);
  font-family: var(--mono-ui);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.16em;
  line-height: 1.6;
}

.eyebrow span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-width: 22px;
  height: 18px;
  padding: 0 5px;
  background: var(--blue);
  color: #fff;
  font-size: 10px;
}

h2 {
  font-family: var(--serif);
  font-size: var(--fs-h2);
  line-height: 1.5;
  letter-spacing: 0.05em;
}

h2 em {
  color: var(--blue);
  font-style: normal;
}

.section-head {
  margin-bottom: var(--block-gap);
}

.section-head p {
  max-width: 42em;
  margin-top: 18px;
  color: var(--text-soft);
}

.button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 56px;
  padding: 0 26px;
  border-radius: 999px;
  font-size: clamp(13px, 1.1vw, 15px);
  font-weight: 700;
  letter-spacing: 0.03em;
  line-height: 1.4;
  text-align: center;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.18s ease;
}

.button svg {
  flex: 0 0 auto;
}

.button--line {
  background: var(--green);
  color: #fff;
  box-shadow: var(--shadow-cta);
}

.button--line:hover {
  background: var(--green-dark);
  transform: translateY(-2px);
}

.button--ghost {
  color: #fff;
  border-bottom: 1px solid rgba(255, 255, 255, 0.55);
  border-radius: 0;
  min-height: auto;
  padding: 0 0 4px;
  font-size: 13px;
}

.button--ghost:hover {
  border-color: #fff;
}

.button--blue {
  background: var(--blue);
  color: #fff;
}

.button--blue:hover {
  background: var(--blue-deep);
  transform: translateY(-2px);
}

.button--copy,
.prompt-sec .button--copy {
  background: var(--blue);
  color: #fff;
  box-shadow: 0 8px 20px rgba(8, 108, 181, 0.28);
}

.button--copy:hover,
.prompt-sec .button--copy:hover {
  background: var(--blue-deep);
  color: #fff;
  transform: translateY(-2px);
}

.button--on-hero {
  background: #fff;
  color: var(--blue);
  box-shadow: 0 10px 24px rgba(3, 34, 58, 0.16);
}

.button--on-hero:hover {
  transform: translateY(-2px);
  background: #f4f9fc;
}

.underlined-link {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding-bottom: 4px;
  border-bottom: 1px solid currentColor;
  color: var(--blue);
  font-size: var(--fs-small);
  font-weight: 700;
}

.underlined-link:hover {
  opacity: 0.75;
}

/* Header */
.site-header {
  position: sticky;
  top: 0;
  z-index: 60;
  display: flex;
  align-items: center;
  gap: 16px;
  height: var(--header-h);
  padding-inline: var(--gutter);
  background: var(--blue);
  color: #fff;
  transition: background 0.25s ease, box-shadow 0.25s ease;
}

.site-header.is-scrolled {
  background: var(--blue-deep);
  box-shadow: 0 6px 20px #06283f38;
}

.brand {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  margin-right: auto;
  min-width: 0;
}

.brand-logo {
  display: block;
  height: 22px;
  width: auto;
}

.brand-mark {
  display: none;
}

.brand__type {
  display: none;
}

.desktop-nav {
  display: none;
  align-items: center;
  gap: clamp(16px, 2.2vw, 32px);
}

.desktop-nav a {
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.04em;
  opacity: 0.92;
}

.desktop-nav a:hover {
  opacity: 1;
  text-decoration: underline;
  text-underline-offset: 6px;
}

.header-cta {
  display: none;
  align-items: center;
  gap: 8px;
  min-height: 42px;
  padding: 0 18px;
  border-radius: 999px;
  background: var(--green);
  color: #fff;
  font-size: 12.5px;
  font-weight: 700;
  white-space: nowrap;
  transition: background 0.18s ease;
}

.header-cta:hover {
  background: var(--green-dark);
}

.mobile-menu-button {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 42px;
  height: 42px;
  border: 1px solid rgba(255, 255, 255, 0.4);
  border-radius: 6px;
  color: #fff;
}

.mobile-menu {
  position: absolute;
  top: var(--header-h);
  left: 0;
  right: 0;
  display: none;
  grid-gap: 2px;
  padding: 10px var(--gutter) 18px;
  background: var(--blue-deep);
  box-shadow: 0 18px 30px #06283f4d;
}

.mobile-menu.is-open {
  display: grid;
}

.mobile-menu a {
  padding: 14px 2px;
  border-bottom: 1px solid rgba(255, 255, 255, 0.16);
  font-size: 14px;
  font-weight: 700;
}

.mobile-menu__line {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  margin-top: 14px;
  padding: 15px !important;
  border: 0 !important;
  border-radius: 999px;
  background: var(--green);
}

@media (min-width: 901px) {
  .desktop-nav,
  .header-cta {
    display: inline-flex;
  }

  .mobile-menu-button,
  .mobile-menu {
    display: none !important;
  }

  .brand__type {
    display: flex;
    flex-direction: column;
    gap: 4px;
    line-height: 1;
    padding-left: 12px;
    border-left: 1px solid rgba(255, 255, 255, 0.28);
  }

  .brand-logo {
    height: 26px;
  }

  .brand__type strong {
    font-size: 14px;
    letter-spacing: 0.1em;
  }

  .brand__type small {
    font-family: var(--mono-ui);
    font-size: 9px;
    letter-spacing: 0.16em;
    opacity: 0.8;
  }
}

/* Hero */
.hero {
  position: relative;
  display: grid;
  grid-template-rows: 1fr auto;
  padding-top: clamp(56px, 8vw, 96px);
  overflow: hidden;
  isolation: isolate;
  color: #fff;
  background: linear-gradient(150deg, #0e7cc9, #086cb5 48%, #065a96);
}

.hero::before {
  content: "";
  position: absolute;
  inset: 0;
  background: radial-gradient(circle at 78% 18%, rgba(255, 255, 255, 0.14), transparent 58%);
  pointer-events: none;
  z-index: 1;
}

.hero__inner {
  position: relative;
  z-index: 2;
  display: grid;
  align-content: center;
  justify-items: center;
  text-align: center;
  padding-bottom: clamp(36px, 6vw, 64px);
}

.hero__eyebrow {
  margin: 0 0 clamp(18px, 2.6vw, 30px);
  color: #ffffffb8;
  font-family: var(--mono-ui);
  font-size: clamp(9px, 1vw, 11px);
  font-weight: 600;
  letter-spacing: 0.28em;
}

.hero__heading {
  display: block;
  font-family: var(--serif);
  font-size: var(--fs-display);
  font-weight: 400;
  letter-spacing: 0.08em;
  line-height: 1.45;
  text-shadow: 0 2px 18px rgba(3, 34, 58, 0.28);
}

.hero__heading span {
  display: inline-block;
}

.hero__sub {
  margin-top: 14px;
  font-family: var(--serif);
  font-size: clamp(16px, 2vw, 22px);
  letter-spacing: 0.12em;
  color: #ffffffd6;
}

.hero__lead {
  max-width: 36em;
  margin: clamp(20px, 2.8vw, 30px) 0 0;
  color: #ffffffe0;
  font-size: clamp(13px, 1.1vw, 15px);
  line-height: 2.05;
}

.hero__actions {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: clamp(14px, 2vw, 26px);
  width: 100%;
  margin-top: clamp(26px, 3.4vw, 40px);
}

.hero__actions .button--on-hero {
  min-height: 60px;
  padding-inline: clamp(24px, 3vw, 40px);
}

.hero__note {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 6px 12px;
  max-width: 44em;
  margin: clamp(24px, 3vw, 34px) 0 0;
  padding: 14px 20px;
  border: 1px solid rgba(255, 255, 255, 0.26);
  border-radius: 4px;
  background: #03223a42;
  color: #ffffffdb;
  font-size: var(--fs-small);
  line-height: 1.9;
}

.hero__note span {
  flex: 0 0 auto;
  padding: 3px 10px;
  border-radius: 999px;
  background: #ffffff24;
  font-family: var(--mono-ui);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.1em;
}

.hero__note b {
  color: #9fe6c0;
}

.hero__fig {
  width: min(100%, 720px);
  margin-top: clamp(28px, 4vw, 44px);
  filter: drop-shadow(0 18px 30px rgba(3, 34, 58, 0.28));
}

.hero__proof {
  position: relative;
  z-index: 2;
  border-top: 1px solid rgba(255, 255, 255, 0.2);
  background: #031e324d;
}

.hero__proof-inner {
  display: flex;
  flex-wrap: wrap;
  justify-content: center;
  gap: 6px 0;
  padding: 14px 0;
}

.hero__proof-inner span {
  display: inline-flex;
  align-items: baseline;
  gap: 7px;
  padding: 4px clamp(14px, 2.4vw, 30px);
  color: #ffffffc7;
  font-size: var(--fs-micro);
  letter-spacing: 0.04em;
  white-space: nowrap;
}

.hero__proof-inner span + span {
  border-left: 1px solid rgba(255, 255, 255, 0.2);
}

.hero__proof-inner b {
  color: #fff;
  font-family: var(--mono-ui);
  font-size: 13.5px;
  font-weight: 700;
}

@media (min-width: 901px) {
  .hero {
    min-height: min(88vh, 820px);
  }

  .hero__heading {
    letter-spacing: 0.1em;
  }
}

@media (max-width: 560px) {
  .hero__proof-inner span {
    flex: 1 1 100%;
    justify-content: center;
  }

  .hero__proof-inner span + span {
    border-left: 0;
    border-top: 1px solid rgba(255, 255, 255, 0.14);
  }
}

/* Sections */
.what,
.howto,
.input,
.trouble,
.customize,
.prompt-sec {
  padding: var(--section-y) 0;
}

.what,
.input,
.customize {
  background: var(--paper);
}

.howto,
.trouble {
  background: var(--blue-tint);
}

.prompt-sec {
  background: var(--blue-tint);
  color: var(--text);
}

.prompt-sec .eyebrow {
  color: var(--blue);
}

.prompt-sec .eyebrow span {
  background: var(--blue);
  color: #fff;
}

.prompt-sec h2 em {
  color: var(--blue);
}

.prompt-sec .section-head p {
  color: var(--text-soft);
}

.lead {
  max-width: 42em;
  color: var(--text-soft);
}

.figure-scroll {
  overflow-x: auto;
  margin: 8px 0 0;
  padding-bottom: 8px;
}

.figure-scroll svg {
  min-width: 640px;
}

.cover-fig-wrap .figure-scroll svg,
.hero__fig {
  min-width: 0;
}

figure {
  margin: 0;
}

figcaption {
  margin-top: 14px;
  color: var(--text-faint);
  font-size: var(--fs-small);
  line-height: 1.8;
}

.note {
  margin-top: 28px;
  padding: 18px 20px;
  background: var(--blue-pale);
  border-left: 3px solid var(--blue);
  border-radius: 0 4px 4px 0;
  color: var(--text);
  font-size: var(--fs-small);
  line-height: 1.9;
}

.note strong {
  color: var(--blue);
}

.callout {
  margin-top: 28px;
  padding: 18px 20px;
  border: 1px solid var(--shu);
  background: var(--shu-bg);
  border-radius: 4px;
  font-size: var(--fs-small);
  line-height: 1.9;
}

.callout .h {
  display: block;
  margin-bottom: 6px;
  color: var(--shu);
  font-family: var(--serif);
  font-size: 15px;
  letter-spacing: 0.04em;
}

.steps {
  display: grid;
  gap: 18px;
}

.step {
  display: grid;
  grid-template-columns: 72px minmax(0, 1fr);
  gap: 18px;
  padding: clamp(22px, 2.4vw, 28px);
  border: 1px solid var(--rule);
  border-top: 3px solid var(--blue);
  border-radius: 0 0 4px 4px;
  background: #fff;
  box-shadow: var(--shadow-card);
}

.step-n {
  font-family: var(--mono-ui);
  color: var(--blue);
  line-height: 1;
}

.step-n b {
  display: block;
  font-size: 28px;
  letter-spacing: -0.04em;
}

.step-n em {
  display: block;
  margin-top: 8px;
  font-style: normal;
  font-size: 9px;
  font-weight: 700;
  letter-spacing: 0.16em;
}

.step-b h3 {
  margin-bottom: 8px;
  font-size: clamp(15px, 1.3vw, 17px);
  font-weight: 700;
  letter-spacing: 0.01em;
  line-height: 1.65;
}

.step-b p {
  color: var(--text-soft);
  font-size: var(--fs-small);
  line-height: 1.9;
}

.step-b p + p {
  margin-top: 8px;
}

.shu-inline {
  margin-top: 12px !important;
  padding: 12px 14px;
  border-left: 3px solid var(--shu);
  background: var(--shu-bg);
  color: var(--text);
  border-radius: 0 4px 4px 0;
}

.kbd {
  display: inline-block;
  padding: 1px 8px;
  border: 1px solid var(--rule-strong);
  border-radius: 4px;
  background: #fff;
  color: var(--blue-ink);
  font-family: ui-monospace, "Noto Sans JP", monospace;
  font-size: 12px;
  white-space: nowrap;
}

.h3 {
  margin: 36px 0 12px;
  padding-left: 12px;
  border-left: 3px solid var(--shu);
  font-family: var(--serif);
  font-size: var(--fs-h3);
  letter-spacing: 0.04em;
  line-height: 1.5;
}

.body-copy {
  max-width: 44em;
  color: var(--text-soft);
}

.body-copy + .body-copy {
  margin-top: 12px;
}

strong.ink {
  color: var(--text);
  font-weight: 700;
}

/* Q&A */
.qa-list {
  display: grid;
  gap: 0;
}

.qa {
  border-top: 1px solid var(--rule);
  padding: 22px 0;
  background: #fff;
}

.qa:last-child {
  border-bottom: 1px solid var(--rule);
}

.qa .q {
  margin-bottom: 8px;
  font-family: var(--serif);
  font-size: 17px;
  letter-spacing: 0.03em;
  line-height: 1.7;
}

.qa .q::before {
  content: "Q ";
  color: var(--shu);
  font-family: var(--mono-ui);
  font-weight: 700;
}

.qa .a {
  color: var(--text-soft);
  font-size: var(--fs-small);
  line-height: 1.9;
}

.qa .a::before {
  content: "A ";
  color: var(--blue);
  font-family: var(--mono-ui);
  font-weight: 700;
}

/* Table */
.table-wrap {
  overflow-x: auto;
  margin-top: 8px;
}

table {
  width: 100%;
  min-width: 640px;
  border-collapse: collapse;
  font-size: var(--fs-small);
}

th,
td {
  border: 1px solid var(--rule);
  padding: 14px 16px;
  text-align: left;
  vertical-align: top;
  line-height: 1.8;
}

th {
  background: var(--blue-ink);
  color: #fff;
  font-weight: 500;
  letter-spacing: 0.06em;
}

td.k {
  width: 28%;
  background: var(--blue-pale);
  color: var(--blue-ink);
  font-weight: 700;
}

/* Prompt */
.prompt-card {
  overflow: hidden;
  border: 1px solid var(--rule);
  border-radius: 6px;
  background: #fff;
  box-shadow: var(--shadow-card);
}

.prompt-card__bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  min-height: 56px;
  padding: 8px 16px 8px 20px;
  background: var(--blue);
  color: #fff;
}

.prompt-card__bar span {
  font-family: var(--sans);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.08em;
}

.prompt-card__copy {
  min-height: 40px;
  padding: 0 18px;
  border-radius: 999px;
  background: #fff;
  color: var(--blue);
  font-size: 13px;
  font-weight: 700;
  box-shadow: none;
}

.prompt-card__copy:hover {
  background: var(--blue-pale);
  transform: none;
}

.prompt-toolbar {
  display: grid;
  gap: 14px;
  margin: 0;
  padding: 18px 20px;
  border: 0;
  border-bottom: 1px solid var(--rule);
  border-radius: 0;
  background: var(--blue-tint);
}

.field label {
  display: block;
  margin-bottom: 6px;
  color: var(--blue);
  font-family: var(--mono-ui);
  font-size: 10px;
  font-weight: 700;
  letter-spacing: 0.12em;
}

.field input {
  width: 100%;
  min-height: 48px;
  padding: 0 14px;
  border: 1px solid var(--rule);
  border-radius: 4px;
  background: #fff;
  color: var(--text);
}

.prompt-box {
  position: relative;
  border: 0;
  border-radius: 0;
  background: #fff;
}

.prompt-box pre {
  margin: 0;
  max-height: 560px;
  overflow: auto;
  padding: 22px 24px;
  color: var(--text);
  font-family: ui-monospace, "SFMono-Regular", "Noto Sans JP", monospace;
  font-size: 12.5px;
  line-height: 1.75;
  white-space: pre-wrap;
  word-break: break-word;
}

.prompt-foot {
  margin-top: 22px;
  color: var(--text-faint);
  font-size: var(--fs-small);
  line-height: 1.9;
}

.prompt-fields {
  display: grid;
  gap: 12px;
}

@media (min-width: 701px) {
  .prompt-fields {
    grid-template-columns: 1fr 1fr;
    align-items: end;
  }
}

.copied-toast {
  position: fixed;
  left: 50%;
  bottom: 28px;
  z-index: 80;
  transform: translateX(-50%) translateY(12px);
  padding: 12px 20px;
  border-radius: 999px;
  background: var(--blue-ink);
  color: #fff;
  font-size: 13px;
  font-weight: 700;
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.2s ease, transform 0.2s ease;
  box-shadow: 0 12px 28px rgba(6, 40, 63, 0.28);
}

.copied-toast.is-on {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* Footer / floating */
.site-footer {
  padding: 40px 0 calc(40px + env(safe-area-inset-bottom));
  background: var(--blue-ink);
  color: #ffffffb8;
}

.site-footer__row {
  display: grid;
  gap: 14px;
  justify-items: center;
  text-align: center;
  font-size: 11.5px;
}

.brand--footer {
  margin: 0;
}

.brand--footer .brand__type {
  display: flex;
  flex-direction: column;
  gap: 3px;
  color: #fff;
  line-height: 1;
}

.brand--footer .brand__type strong {
  font-size: 13px;
  letter-spacing: 0.1em;
}

.brand--footer .brand__type small {
  font-family: var(--mono-ui);
  font-size: 8.5px;
  letter-spacing: 0.16em;
  opacity: 0.75;
}

.floating-copy {
  position: fixed;
  z-index: 70;
  left: 12px;
  right: 12px;
  bottom: calc(12px + env(safe-area-inset-bottom));
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 10px;
  min-height: 56px;
  border-radius: 999px;
  background: var(--blue);
  color: #fff;
  font-size: 14px;
  font-weight: 700;
  letter-spacing: 0.03em;
  box-shadow: 0 12px 28px rgba(0, 75, 124, 0.35);
}

.floating-copy:hover {
  background: var(--blue-deep);
}

@media (min-width: 901px) {
  .floating-copy {
    left: auto;
    right: 26px;
    bottom: 26px;
    min-height: 58px;
    padding: 0 24px;
  }
}

@media (max-width: 900px) {
  body {
    padding-bottom: 84px;
  }

  .step {
    grid-template-columns: 1fr;
    gap: 10px;
  }
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }

  *,
  *::before,
  *::after {
    animation-duration: 0.001ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.001ms !important;
  }
}