/* --------------------------------------------------------------------------
   1. Design tokens (Figma Variables)
   -------------------------------------------------------------------------- */
:root {
  /* Color (Figma Variables) */
  --color-neutral-white: #ffffff;        /* Color/Neutral/White */
  --color-neutral-black: #0d0d0d;        /* Color/Neutral/Black */
  --color-neutral-gray-200: #e7e7e7;     /* Color/Neutral/Gray/200 */
  --color-black: #000912;                /* black */
  --color-base: #093556;                 /* base */

  /* Color (Figma Styles / design values) */
  --color-brand-start: #0080ae;
  --color-brand-end: #154061;
  --gradation: linear-gradient(to right, var(--color-brand-start), var(--color-brand-end)); /* gradation */
  --color-button-dark: #15466d;
  --color-contact-button: #194160;
  --color-kv-overlay: #122d48;
  --color-placeholder: #d9d9d9;

  /* Font */
  --font-base: "Inter", "Noto Sans JP", sans-serif;
  --font-heading: "Noto Sans JP", "Inter", sans-serif;

  /* Typography: sp/h2 */
  --fs-h2: 32px;
  --ls-h2: 1.6px;
  --lh-heading: 1.6;

  /* Layout */
  --container: 1200px;
  --gutter: 16px;
  --header-px: 16px;
  --section-py: 40px;
  --section-py-compact: 32px;
  --section-py-plan: 24px;
  --stack-gap: 24px;
  --title-gap: 16px;

  /* Text */
  --fs-lead: 17px;
  --fs-note: 13px;

  /* KV */
  --kv-height: 330px;
  --kv-logo-width: 434px;
  --kv-title-size: 20px;
  --kv-badge-size: 23px;

  /* Partner logos */
  --partner-gap: 8px;
  --partner-ntt-width: 152px;
  --partner-pixellot-width: 131px;
  --partner-cross-size: 30px;

  /* Step slider */
  --step-card-width: min(358px, calc(100vw - 2 * var(--gutter)));
  --step-card-gap: 27px;
  --step-card-padding: 21.2px;
  --step-label-size: 32px;
  --step-arrow-size: 31.8px;
  --step-title-size: 24px;
  --step-title-ls: 1.2px;
  --step-text-size: 16px;
  --step-head-gap: 20px;

  /* Plan */
  --plan-price-main: 28px;
  --plan-price-unit: 16px;
  --plan-label-size: 16px;

  /* Sponsor */
  --sponsor-large-width: 260px;
  --sponsor-medium-width: 171px;
  --powered-logo-width: 164px;
  --sponsor-font-size: 24px;
}

@media (min-width: 768px) {
  :root {
    /* Typography: pc/h2 */
    --fs-h2: 48px;
    --ls-h2: 2.4px;

    --header-px: 40px;
    --section-py: 64px;
    --section-py-compact: 64px;
    --section-py-plan: 64px;
    --stack-gap: 32px;
    --title-gap: 32px;

    --fs-lead: 24px;

    --kv-height: 600px;
    --kv-logo-width: min(1408px, 100%);
    --kv-title-size: 36px;
    --kv-badge-size: 48px;

    --partner-gap: 16px;
    --partner-ntt-width: 233px;
    --partner-pixellot-width: 201px;
    --partner-cross-size: 48px;

    --step-card-width: min(800px, calc(100vw - 80px));
    --step-card-gap: 42.4px;
    --step-card-padding: 42.4px;
    --step-label-size: 42.4px;
    --step-arrow-size: 63.6px;
    --step-title-size: 32px;
    --step-title-ls: 1.6px;
    --step-text-size: 18px;
    --step-head-gap: 40.6px;

    --plan-price-main: 36px;
    --plan-price-unit: 20px;
    --plan-label-size: 24px;

    --sponsor-large-width: 411px;
    --sponsor-medium-width: 271px;
    --sponsor-font-size: 28px;
    --powered-logo-width: 197px;
  }
}

/* --------------------------------------------------------------------------
   2. Base
   -------------------------------------------------------------------------- */
*,
*::before,
*::after {
  box-sizing: border-box;
}

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

@media (prefers-reduced-motion: no-preference) {
  html {
    scroll-behavior: smooth;
  }
}

body {
  margin: 0;
  background-color: var(--color-base);
  color: var(--color-neutral-white);
  font-family: var(--font-base);
  font-size: 16px;
  line-height: 1.6;
  overflow-x: hidden;
}

h1,
h2,
h3,
p,
dl,
dd,
ul {
  margin: 0;
  padding: 0;
}

ul {
  list-style: none;
}

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

a {
  color: inherit;
}

button {
  font: inherit;
  color: inherit;
}

:focus-visible {
  outline: 3px solid var(--color-neutral-white);
  outline-offset: 3px;
  box-shadow: 0 0 0 6px var(--color-brand-start);
}

/* Utilities */
.u-sp {
  display: inline;
}

.u-pc {
  display: none;
}

@media (min-width: 768px) {
  .u-sp {
    display: none;
  }

  .u-pc {
    display: inline;
  }
}

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

.skip-link {
  position: absolute;
  top: 0;
  left: 0;
  z-index: 100;
  padding: 8px 16px;
  background: var(--color-neutral-white);
  color: var(--color-black);
  transform: translateY(-100%);
}

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

/* --------------------------------------------------------------------------
   3. Components
   -------------------------------------------------------------------------- */

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

.section {
  padding-block: var(--section-py);
}

.section--compact {
  padding-block: var(--section-py-compact);
}

.section--plan {
  padding-block: var(--section-py-plan);
}

.section__stack {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: var(--stack-gap);
}

@media (min-width: 768px) {
  .section__stack--wide-gap {
    --stack-gap: 40px;
  }
}

/* Component: section-title */
.section-title {
  display: flex;
  flex-direction: column;
  gap: var(--title-gap);
  width: 100%;
  text-align: center;
}

.section-title__heading {
  font-family: var(--font-heading);
  font-size: var(--fs-h2);
  font-weight: 700;
  line-height: var(--lh-heading);
  letter-spacing: var(--ls-h2);
}

.section-title__lead {
  font-family: var(--font-heading);
  font-size: 16px;
  line-height: 1.5;
  text-align: center;
}

/* Component: header */
.site-header {
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8px var(--header-px);
  background: var(--gradation);
}

.site-header__brand {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
  color: var(--color-neutral-white);
  text-decoration: none;
}

.site-header__logo {
  width: 40px;
  height: auto;
}

.site-header__name {
  font-family: var(--font-heading);
  font-size: 28px;
  font-weight: 700;
  line-height: var(--lh-heading);
  white-space: nowrap;
}

/* Component: KV (background-img + kv-logo + h1) */
.kv {
  position: relative;
  display: flex;
  flex-direction: column;
  align-items: center;
  min-height: var(--kv-height);
  padding: 13px var(--gutter) 24px;
  overflow: hidden;
  background-color: var(--color-neutral-white);
  background-image: url("img/kv-bg-sp.png"); /* SP */
  background-position: center top;
  background-repeat: no-repeat;
  background-size: cover;
}

/* 上部をネイビーにフェードさせるオーバーレイ */
.kv::before {
  content: "";
  position: absolute;
  inset: 0;
  background: linear-gradient(to bottom, var(--color-kv-overlay), rgba(18, 45, 72, 0));
  pointer-events: none;
}

.kv > * {
  position: relative;
  z-index: 1;
}

.kv-logo {
  flex-shrink: 0;
  width: var(--kv-logo-width);
  max-width: none;
  height: auto;
  width: 100%;
}

.kv-title {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  width: 100%;
  max-width: 582px;
  margin-top: 6px;
  font-family: var(--font-heading);
  font-weight: 700;
  text-align: center;
  flex-wrap: wrap;
}

.kv-title__name {
  font-size: var(--kv-title-size);
  line-height: var(--lh-heading);
}

.kv-title__badge {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 4px 16px;
  background: var(--gradation);
  font-family: var(--font-base);
  font-size: var(--kv-badge-size);
  line-height: var(--lh-heading);
  white-space: nowrap;
}

@media (min-width: 768px) {
  .kv {
    padding: 10px var(--gutter) 64px;
    background-image: url("img/kv-bg-pc.png"); /* PC */
  }

  .kv-title {
    flex-direction: row;
    justify-content: center;
    gap: 24px;
    max-width: none;
    margin-top: -17px;
  }
}

/* Intro */
.intro {
  font-size: var(--fs-lead);
  line-height: 1.6;
  text-align: center;
}

.partner {
  display: flex;
  flex-direction: column;
  gap: 12px;
  width: 100%;
}

.partner__logos {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--partner-gap);
}

.partner__logo--ntt {
  width: var(--partner-ntt-width);
}

.partner__logo--pixellot {
  width: var(--partner-pixellot-width);
}

.partner__cross {
  font-size: var(--partner-cross-size);
  font-weight: 300;
  line-height: normal;
}

.note {
  font-size: var(--fs-note);
  line-height: 1.8;
  text-align: center;
}

/* Component: video (YouTube iframe) */
.section--movie .container {
  max-width: 832px; /* 800 + gutter */
}

.video {
  width: 100%;
  max-width: 800px;
  margin-inline: auto;
  aspect-ratio: 16 / 9;
  background-color: #000;
}

.video__frame {
  display: block;
  width: 100%;
  height: 100%;
  border: 0;
}

/* Component: button */
.btn {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 6px;
  width: 100%;
  max-width: 360px;
  margin: auto;
  padding: 12px 32px 12px 26px;
  border: 3px solid transparent;
  border-radius: 99px;
  font-family: var(--font-base);
  font-weight: 700;
  line-height: var(--lh-heading);
  text-align: center;
  text-decoration: none;
  white-space: nowrap;
  transition: filter 0.2s ease;
}

.btn:hover {
  filter: brightness(1.08);
}

.btn__icon {
  flex-shrink: 0;
  width: 48px;
  height: 48px;
}

.btn__icon--megaphone {
  width: 40px;
  height: auto;
  margin: 4px;
}

.btn__text {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
}

.btn__main {
  font-size: 28px;
  letter-spacing: 1.4px;
}

.btn__sub {
  font-size: 16px;
  letter-spacing: 0.8px;
}

/* primary: 白背景 + グラデーションテキスト */
.btn--primary {
  background-color: var(--color-neutral-white);
  border-color: var(--color-neutral-white);
  color: var(--color-brand-start);
}

.btn--primary .btn__main {
  margin-bottom: -5px;
}

.btn--primary .btn__main,
.btn--primary .btn__sub {
  color: var(--color-brand-start);
}

@supports (background-clip: text) or (-webkit-background-clip: text) {
  .btn--primary .btn__main,
  .btn--primary .btn__sub {
    background: var(--gradation);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
  }
}

/* secondary: 濃紺背景 + 白枠 */
.btn--secondary {
  background-color: var(--color-button-dark);
  border-color: var(--color-neutral-white);
  color: var(--color-neutral-white);
}

.btn--secondary .btn__main {
  font-size: 28px;
}

/* rect: 角丸なし (お問い合わせ) */
.btn--rect {
  display: inline-flex;
  width: auto;
  gap: 10px;
  padding: 16px 40px;
  border-radius: 0;
  border-color: var(--color-neutral-white);
  background-color: var(--color-button-dark);
  color: var(--color-neutral-white);
  font-family: var(--font-heading);
  font-size: 20px;
  line-height: 1.5;
  letter-spacing: 1px;
}

.btn--rect .btn__icon {
  width: 32px;
  height: 32px;
}

@media (min-width: 768px) {
  .btn--rect {
    background-color: var(--color-contact-button);
  }
}

/* Register */
.register {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 20px;
  width: 100%;
  margin-top: 24px;
}

.register__col {
  display: flex;
  flex-direction: column;
  gap: 12px;
  width: min(380px, 100%);
  padding: 0 1rem;
}

@media (min-width: 768px) {
  .register__col {
    width: 100%;
  }
}

/* Component: plan-card */
.plan {
  display: flex;
  flex-direction: column;
  gap: 24px;
  width: 100%;
}

.plan-card {
  display: flex;
  flex: 1 1 0;
  flex-direction: column;
  gap: 16px;
  min-width: 0;
  padding: 24px;
  background-color: var(--color-neutral-white);
  color: var(--color-neutral-black);
}

.plan-card__head {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.plan-card__label {
  padding: 4px 16px;
  background: var(--gradation);
  color: var(--color-neutral-white);
  font-size: var(--plan-label-size);
  font-weight: 700;
  line-height: var(--lh-heading);
  text-align: center;
}

.plan-card__price {
  font-weight: 700;
  line-height: var(--lh-heading);
  text-align: center;
  color: var(--color-brand-start);
}

@supports (background-clip: text) or (-webkit-background-clip: text) {
  .plan-card__price {
    background: var(--gradation);
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    color: transparent;
  }
}

.plan-card__price-main {
  font-size: var(--plan-price-main);
}

.plan-card__price-unit {
  font-size: var(--plan-price-unit);
}

.plan-card__line {
  width: 100%;
  height: 2px;
  margin: 0;
  border: 0;
  background: var(--gradation);
}

.plan-card__body {
  font-size: 16px;
  line-height: 1.6;
}

@media (min-width: 768px) {
  .plan {
    flex-direction: row;
    align-items: stretch;
  }
}

/* Component: sponsor logo */
.sponsor-logos {
  align-items: center;
  width: 100%;
}

.sponsor-logos__item {
  font-weight: 700;
  font-size: var(--sponsor-font-size);
  text-align: center;
}

/* Powered by */
.powered {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 24px;
  padding: 40px var(--gutter);
  font-family: var(--font-heading);
  line-height: 1.5;
}

.powered__logo {
  width: var(--powered-logo-width);
}

@media (min-width: 768px) {
  .powered {
    padding-top: 64px;
  }
}

/* Component: footer */
.site-footer {
  padding: 24px 40px;
  background: var(--gradation);
  font-family: var(--font-heading);
  text-align: center;
}

.site-footer__links {
  display: flex;
  flex-wrap: wrap;
  align-items: flex-start;
  justify-content: center;
  gap: 16px 40px;
  max-width: 310px;
  margin-inline: auto;
  font-size: 16px;
  line-height: normal;
}

.site-footer__links a {
  text-decoration: none;
  white-space: nowrap;
}

.site-footer__links a:hover {
  text-decoration: underline;
}

.site-footer__copy {
  margin-top: 24px;
  font-size: 14px;
  line-height: normal;
}

@media (min-width: 768px) {
  .site-footer__links {
    max-width: none;
  }
}

/* --------------------------------------------------------------------------
   4. Component: slider (ご利用方法)
   - scroll-snap でスワイプ操作（SP）
   - 三角矢印ボタンで前後のSTEPへ移動（PC/SP共通）
   -------------------------------------------------------------------------- */
.slider {
  position: relative;
  width: 100%;
}

.slider__track {
  position: relative;
  display: flex;
  gap: var(--step-card-gap);
  padding-inline: calc((100% - var(--step-card-width)) / 2);
  overflow-x: auto;
  overscroll-behavior-x: contain;
  scroll-snap-type: x mandatory;
  scrollbar-width: none;
  -webkit-overflow-scrolling: touch;
}

.slider__track::-webkit-scrollbar {
  display: none;
}

.slider__track:focus-visible {
  outline-offset: -3px;
}

/* マウスドラッグ */
.slider__track {
  cursor: grab;
}

.slider__track.is-dragging {
  cursor: grabbing;
  scroll-snap-type: none;
  user-select: none;
}

.slider__track img {
  -webkit-user-drag: none;
  user-select: none;
  max-width: 300px;
}

.slider__slide {
  flex: 0 0 var(--step-card-width);
  scroll-snap-align: center;
  scroll-snap-stop: always;
  container-type: inline-size;
}

/* step-card */
.step-card {
  display: flex;
  flex-direction: column;
  align-items: center;
  height: 100%;
   max-width: 800px;
  padding: var(--step-card-padding);
  background-color: var(--color-neutral-white);
  color: var(--color-black);
}

.step-card__media {
  width: 100%;
  max-width: 632.6px;
  background-color: var(--color-placeholder);
  object-fit: cover;
}

.step-card__body {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  width: 100%;
  padding-top: 16px;
}

.step-card__head {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--step-head-gap);
}

.step-card__label {
  font-family: var(--font-base);
  font-size: var(--step-label-size);
  font-weight: 700;
  line-height: 1.5;
  white-space: nowrap;

          background: var(--gradation);
        -webkit-background-clip: text;
        background-clip: text;
        -webkit-text-fill-color: transparent;
        color: transparent;
}

.step-card__title {
  font-family: var(--font-heading);
  font-size: var(--step-title-size);
  font-weight: 700;
  line-height: var(--lh-heading);
  letter-spacing: var(--step-title-ls);
  text-align: center;
}

.step-card__text {
  width: 100%;
  font-family: var(--font-heading);
  font-size: var(--step-text-size);
  line-height: 1.5;
}

.step-card__text span {
  font-weight: 700;
}

/* arrow (三角矢印) */
.slider__arrow {
  display: grid;
  flex-shrink: 0;
  place-items: center;
  width: var(--step-arrow-size);
  height: var(--step-arrow-size);
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: none;
  cursor: pointer;
  transition: opacity 0.2s ease, transform 0.2s ease;
}

.slider__arrow img {
  width: 84%;
  height: auto;
  pointer-events: none;
}

.slider__arrow:hover:not(:disabled) {
  transform: scale(1.1);
}

.slider__arrow:disabled {
  opacity: 0.25;
  cursor: default;
}

.slider__arrow:focus-visible {
  outline-color: var(--color-brand-start);
  box-shadow: none;
}

/* カード自体の幅で横並びに切り替え（画面幅ではなくカード幅が基準） */
@container (min-width: 720px) {
  .step-card {
    --step-label-size: 36px;
    --step-arrow-size: 48px;
    --step-head-gap: 24px;
    flex-direction: row;
    align-items: flex-start;
    justify-content: center;
    gap: 32px;
    padding: 32px;
  }

  .step-card__media {
    flex: 0 0 52%;
    width: auto;
    min-width: 0;
  }

  .step-card__body {
    flex: 1 1 0;
    gap: 16px;
    min-width: 0;
    padding-top: 32px;
  }

  .step-card__text {
    text-align: left;
  }
}

@media (prefers-reduced-motion: reduce) {
  .slider__arrow,
  .btn {
    transition: none;
  }
}