/* ============================================
   Design Tokens
   ============================================ */
:root {
  /* Color */
  --color-base:         #FFFFFF;
  --color-surface:      #F4F5F4;
  --color-accent:       #40916C;
  --color-accent-hover: #74C69D;
  --color-text:         #3D3D3D;
  --color-text-muted:   #888888;
  --color-border:       #E0E2E0;

  /* Typography */
  --font-main: 'Noto Sans JP', sans-serif;
  --font-size-base:  15px;
  --line-height:     1.8;
  --letter-spacing:  0.05em;

  /* Layout */
  --max-width:    1000px;
  --section-py:   80px;
  --container-px: 24px;
  --radius:       8px;
  --radius-lg:    12px;

  /* Transition */
  --transition: 0.25s ease;
}

/* ============================================
   Base
   ============================================ */
body {
  font-family: var(--font-main);
  font-size: var(--font-size-base);
  line-height: var(--line-height);
  letter-spacing: var(--letter-spacing);
  color: var(--color-text);
  background-color: var(--color-base);
}

.container {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--container-px);
}

.section {
  padding: var(--section-py) 0;
}

.section--surface {
  background-color: var(--color-surface);
}

/* ============================================
   Section Heading
   ============================================ */
.section-heading {
  margin-bottom: 48px;
  text-align: center;
}

.section-heading__en {
  display: block;
  font-size: 11px;
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--color-accent);
  text-transform: uppercase;
  margin-bottom: 8px;
}

.section-heading__ja {
  font-size: 26px;
  font-weight: 700;
  color: var(--color-text);
  letter-spacing: 0.08em;
}

/* ============================================
   Button
   ============================================ */
.btn {
  display: inline-block;
  padding: 12px 28px;
  border-radius: var(--radius);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.05em;
  cursor: pointer;
  transition: background-color var(--transition), color var(--transition), border-color var(--transition);
}

.btn--primary {
  background-color: var(--color-accent);
  color: #FFFFFF;
  border: 1.5px solid var(--color-accent);
}

.btn--primary:hover {
  background-color: var(--color-accent-hover);
  border-color: var(--color-accent-hover);
}

.btn--outline {
  background-color: transparent;
  color: var(--color-accent);
  border: 1.5px solid var(--color-accent);
}

.btn--outline:hover {
  background-color: var(--color-accent);
  color: #FFFFFF;
}

/* ============================================
   Navigation
   ============================================ */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  background-color: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(8px);
  border-bottom: 1px solid var(--color-border);
}

.nav__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--container-px);
  height: 60px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  font-size: 18px;
  font-weight: 700;
  color: var(--color-accent);
  letter-spacing: 0.05em;
}

.nav__list {
  display: flex;
  gap: 32px;
}

.nav__link {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text-muted);
  letter-spacing: 0.08em;
  transition: color var(--transition);
  position: relative;
}

.nav__link::after {
  content: '';
  position: absolute;
  bottom: -2px;
  left: 0;
  width: 0;
  height: 1.5px;
  background-color: var(--color-accent);
  transition: width var(--transition);
}

.nav__link:hover {
  color: var(--color-accent);
}

.nav__link:hover::after {
  width: 100%;
}

/* ハンバーガーボタン */
.nav__hamburger {
  display: none;
  flex-direction: column;
  justify-content: center;
  gap: 5px;
  width: 40px;
  height: 40px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 101;
}

.nav__hamburger-line {
  display: block;
  height: 2px;
  background-color: var(--color-text);
  border-radius: 2px;
  transition: transform 0.3s ease, opacity 0.3s ease, width 0.3s ease;
  transform-origin: right center;
}

/* 1本目：長め */
.nav__hamburger-line:nth-child(1) { width: 24px; }
/* 2本目：中くらい（真ん中の横棒）*/
.nav__hamburger-line:nth-child(2) { width: 24px; }
/* 3本目：短め */
.nav__hamburger-line:nth-child(3) { width: 24px; }

/* → に変形 */
.nav__hamburger.is-open .nav__hamburger-line:nth-child(1) {
  width: 13px;
  transform: translateY(7px) translateX(10px) rotate(35deg);
}
.nav__hamburger.is-open .nav__hamburger-line:nth-child(2) {
  width: 22px;
  transform: translateX(2px);
}
.nav__hamburger.is-open .nav__hamburger-line:nth-child(3) {
  width: 13px;
  transform: translateY(-6px) translateX(10px) rotate(-35deg);
}

/* オーバーレイ */
.nav__overlay {
  display: none;
  position: fixed;
  top: 60px;
  left: 0;
  right: 0;
  bottom: 0;
  background-color: rgba(0, 0, 0, 0.75);
  z-index: 99;
}

.nav__overlay.is-open {
  display: block;
}

/* ============================================
   Hero
   ============================================ */
.hero {
  padding-top: calc(60px + 80px);
  padding-bottom: 80px;
}

.hero__inner {
  max-width: var(--max-width);
  margin: 0 auto;
  padding: 0 var(--container-px);
  display: grid;
  grid-template-columns: 1fr 250px;
  gap: 48px;
  align-items: center;
}

.hero__sub {
  display: block;
  font-size: 12px;
  font-weight: 400;
  letter-spacing: 0.2em;
  color: var(--color-accent);
  text-transform: uppercase;
  margin-bottom: 16px;
}

.hero__sub-badge {
  display: inline-block;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.05em;
  text-transform: none;
  color: #0C447C;
  background-color: #E6F1FB;
  border: 1px solid #378ADD;
  border-radius: 99px;
  padding: 2px 10px;
  margin-left: 10px;
  vertical-align: middle;
}

.hero__title {
  font-size: 42px;
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: 0.04em;
  color: var(--color-text);
  margin-bottom: 20px;
}

.hero__title span {
  color: var(--color-accent);
}

.hero__desc {
  font-size: 14px;
  color: var(--color-text-muted);
  line-height: 1.9;
  margin-bottom: 32px;
}

.hero__buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
}

.hero__photo {
  width: 250px;
  height: 250px;
  border-radius: 50%;
  object-fit: cover;
  border: 3px solid var(--color-surface);
}

.hero__photo-placeholder {
  width: 200px;
  height: 200px;
  border-radius: 50%;
  background-color: var(--color-surface);
  border: 3px solid var(--color-border);
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--color-text-muted);
  font-size: 13px;
}

/* ============================================
   About
   ============================================ */
.about__text {
  max-width: 680px;
  margin: 0 auto;
  text-align: left;
  color: var(--color-text-muted);
  font-size: 14px;
  line-height: 2;
}

/* ============================================
   Works（Bento UI）
   ============================================ */
.works__grid {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.works__card {
  background-color: var(--color-base);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  overflow: hidden;
  transition: transform var(--transition), box-shadow var(--transition);
}

.works__card:hover {
  transform: translateY(-4px);
  box-shadow: 0 8px 24px rgba(64, 145, 108, 0.12);
}

.works__card--main {
  grid-column: 1 / 3;
  display: grid;
  grid-template-columns: 1fr 1fr;
  border-color: var(--color-accent);
}

.works__card--wide {
  grid-column: 1 / 3;
}

.works__card-img {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  background-color: var(--color-surface);
}

.works__card-body {
  padding: 20px;
}

.works__card-tag {
  display: inline-block;
  font-size: 11px;
  font-weight: 500;
  letter-spacing: 0.08em;
  padding: 3px 10px;
  border-radius: 99px;
  margin-bottom: 10px;
}

.works__card-tag--accent {
  background-color: rgba(64, 145, 108, 0.12);
  color: var(--color-accent);
}

.works__card-tag--gray {
  background-color: var(--color-surface);
  color: var(--color-text-muted);
}

.works__card-title {
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
}

.works__card-desc {
  font-size: 13px;
  color: var(--color-text-muted);
  line-height: 1.7;
}

.works__card-link {
  display: inline-block;
  margin-top: 12px;
  font-size: 13px;
  color: var(--color-accent);
  font-weight: 500;
  transition: color var(--transition);
}

.works__card-link:hover {
  color: var(--color-accent-hover);
}

/* 学習制作物まとめ */
.works__study {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 12px;
}

.works__study-item {
  display: block;
  border-radius: var(--radius);
  overflow: hidden;
  border: 1px solid var(--color-border);
  transition: transform var(--transition), box-shadow var(--transition);
  text-decoration: none;
}

.works__study-item:hover {
  transform: translateY(-3px);
  box-shadow: 0 6px 16px rgba(64, 145, 108, 0.12);
}

.works__study-item img {
  width: 100%;
  aspect-ratio: 4 / 3;
  object-fit: cover;
  display: block;
  background-color: var(--color-surface);
}

.works__study-label {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: var(--color-text);
  padding: 8px 10px;
  background-color: var(--color-base);
}

/* ============================================
   Skills
   ============================================ */
.skills__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.skills__item {
  background-color: var(--color-base);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 20px 16px;
  text-align: center;
  transition: border-color var(--transition);
}

.skills__item:hover {
  border-color: var(--color-accent);
}

.skills__icon {
  width: 40px;
  height: 40px;
  margin: 0 auto 10px;
}

.skills__icon img {
  width: 100%;
  height: 100%;
  object-fit: contain;
  /* SimpleIconsはデフォルトが黒なのでアクセントカラーに変換 */
  filter: invert(41%) sepia(44%) saturate(512%) hue-rotate(106deg) brightness(88%) contrast(87%);
}

.skills__item:hover .skills__icon img {
  filter: invert(64%) sepia(30%) saturate(400%) hue-rotate(106deg) brightness(100%) contrast(90%);
}

.skills__name {
  font-size: 13px;
  font-weight: 500;
}

/* ============================================
   Blog
   ============================================ */
.blog__list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}

.blog__item {
  display: flex;
  align-items: center;
  gap: 16px;
  background-color: var(--color-base);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  padding: 16px;
  transition: border-color var(--transition), transform var(--transition);
}

.blog__item:hover {
  border-color: var(--color-accent);
  transform: translateX(4px);
}

.blog__thumb {
  width: 64px;
  height: 64px;
  border-radius: var(--radius);
  object-fit: cover;
  background-color: var(--color-surface);
  flex-shrink: 0;
}

.blog__content {
  flex: 1;
}

.blog__title {
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 4px;
  line-height: 1.5;
}

.blog__date {
  font-size: 12px;
  color: var(--color-text-muted);
}

.blog__arrow {
  color: var(--color-accent);
  flex-shrink: 0;
}

/* ============================================
   Contact
   ============================================ */
.contact__form {
  max-width: 560px;
  margin: 0 auto;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.form__group {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.form__label {
  font-size: 13px;
  font-weight: 500;
  color: var(--color-text);
}

.form__input,
.form__textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 14px;
  color: var(--color-text);
  background-color: var(--color-base);
  border: 1px solid var(--color-border);
  border-radius: var(--radius);
  transition: border-color var(--transition), outline var(--transition);
  outline: none;
}

.form__input:focus,
.form__textarea:focus {
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(64, 145, 108, 0.12);
}

.form__textarea {
  resize: vertical;
  min-height: 140px;
}

.contact__submit {
  align-self: center;
  min-width: 180px;
}

.form__honeypot {
  position: absolute;
  left: -9999px;
  top: -9999px;
  width: 1px;
  height: 1px;
  overflow: hidden;
}

.form__status {
  min-height: 1.2em;
  font-size: 13px;
  text-align: center;
}

.form__status--ok {
  color: var(--color-accent);
}

.form__status--error {
  color: #c0392b;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  padding: 32px 0;
  background-color: var(--color-text);
  text-align: center;
}

.footer__text {
  font-size: 12px;
  color: rgba(255, 255, 255, 0.5);
  letter-spacing: 0.08em;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 768px) {
  :root {
    --section-py: 56px;
  }

  .nav__hamburger {
    display: flex;
  }

  .nav__list {
    position: fixed;
    top: 220px;
    right: -100%;
    width: 100%;
    height: calc(100% - 220px);
    background-color: transparent;
    flex-direction: column;
    justify-content: flex-start;
    align-items: center;
    gap: 40px;
    z-index: 101;
    transition: right 0.35s ease;
  }

  .nav__list.is-open .nav__link {
    color: #FFFFFF;
  }

  .nav__list.is-open {
    right: 0;
  }

  .nav__link {
    font-size: 16px;
  }

  .hero__inner {
    grid-template-columns: 1fr;
    text-align: center;
  }

  .hero__photo-placeholder,
  .hero__photo {
    width: 140px;
    height: 140px;
    margin: 0 auto;
    order: -1;
  }

  .hero__title {
    font-size: 28px;
  }

  .hero__buttons {
    justify-content: center;
  }

  .works__grid {
    grid-template-columns: 1fr;
  }

  .works__study {
    grid-template-columns: repeat(2, 1fr);
  }

  .works__card--main {
    grid-column: 1;
    grid-template-columns: 1fr;
  }

  .works__card--wide {
    grid-column: 1;
  }

  .skills__grid {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (max-width: 480px) {
  .hero__title {
    font-size: 24px;
  }

  .skills__grid {
    grid-template-columns: repeat(2, 1fr);
  }

  .section-heading__ja {
    font-size: 22px;
  }
}