/* =============================================
   KONON — style.css
   Brand red : #E8003B
   BG dark   : #070707
   BG alt    : #0f0f0f
   Text      : #f0f0f0
   Muted     : #4a4a4a
============================================= */

/* ---------- Reset & Base ---------- */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: 'Noto Sans JP', sans-serif;
  background: #070707;
  color: #f0f0f0;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

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

/* ---------- CSS Variables ---------- */
:root {
  --red:        #E8003B;
  --bg:         #070707;
  --bg-alt:     #0f0f0f;
  --bg-card:    #0d0d0d;
  --text:       #f0f0f0;
  --text-muted: #4a4a4a;
  --text-sub:   #aaaaaa;
  --border:     rgba(255, 255, 255, 0.06);
  --border-red: rgba(232, 0, 59, 0.2);
  --nav-h:      70px;
  --max-w:      1100px;
  --pad-x:      40px;
  --font-disp:  'Bebas Neue', 'Noto Sans JP', sans-serif;
}

/* ---------- Keyframe Animations ---------- */
@keyframes kPulse {
  0%, 100% { opacity: 0.13; }
  50%       { opacity: 0.24; }
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(22px); }
  to   { opacity: 1; transform: translateY(0); }
}

@keyframes lineIn {
  from { transform: scaleX(0); }
  to   { transform: scaleX(1); }
}



/* ---------- Scroll Progress Bar ---------- */
.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  width: 100%;
  background: var(--red);
  transform-origin: left;
  transform: scaleX(0);
  z-index: 300;
  transition: transform 0.08s linear;
}

/* ---------- Scroll Reveal ---------- */
.reveal {
  opacity: 0;
  transform: translateY(28px);
  transition: opacity 0.7s ease, transform 0.7s ease;
}
.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}
.reveal-delay-1 { transition-delay: 0.12s; }
.reveal-delay-2 { transition-delay: 0.24s; }
.reveal-delay-3 { transition-delay: 0.36s; }

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: 13px 28px;
  font-size: 12px;
  font-family: 'Noto Sans JP', sans-serif;
  font-weight: 700;
  letter-spacing: 0.1em;
  cursor: pointer;
  transition: background 0.2s ease, color 0.2s ease, border-color 0.2s ease;
  border: none;
  white-space: nowrap;
}

.btn--primary {
  background: var(--red);
  color: #fff;
  border: 1px solid var(--red);
}
.btn--primary:hover {
  background: transparent;
  color: var(--red);
}

.btn--ghost {
  background: transparent;
  color: var(--text-muted);
  border: none;
  padding-left: 0;
  padding-right: 0;
}
.btn--ghost:hover {
  color: var(--text);
}

.btn--full {
  width: 100%;
}

/* =============================================
   NAVIGATION
============================================= */
.nav {
  position: fixed;
  top: 0;
  left: 0;
  right: 0;
  z-index: 200;
  transition: background 0.35s ease, border-color 0.35s ease, backdrop-filter 0.35s ease;
  border-bottom: 1px solid transparent;
}

.nav.scrolled {
  background: rgba(7, 7, 7, 0.92);
  border-bottom-color: var(--border);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
}

.nav__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
  height: var(--nav-h);
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.nav__logo {
  display: flex;
  align-items: center;
  gap: 10px;
}

.nav__logo-mark {
  width: 34px;
  height: 34px;
  object-fit: contain;
  mix-blend-mode: screen;
}

.nav__links {
  display: flex;
  align-items: center;
  gap: 32px;
}

.nav__link {
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.1em;
  transition: color 0.2s ease;
}
.nav__link:hover {
  color: var(--text);
}

.nav__cta {
  color: var(--red) !important;
  border: 1px solid var(--red);
  padding: 6px 18px;
  transition: background 0.2s ease, color 0.2s ease !important;
}
.nav__cta:hover {
  background: var(--red);
  color: #fff !important;
}

/* Hamburger (hidden on desktop) */
.nav__hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
  z-index: 210;
}
.nav__hamburger span {
  display: block;
  width: 22px;
  height: 1px;
  background: var(--text);
  transition: transform 0.3s ease, opacity 0.3s ease;
}
.nav__hamburger.open span:nth-child(1) { transform: translateY(6px) rotate(45deg); }
.nav__hamburger.open span:nth-child(2) { opacity: 0; }
.nav__hamburger.open span:nth-child(3) { transform: translateY(-6px) rotate(-45deg); }

/* =============================================
   HERO
============================================= */
.hero {
  min-height: 100vh;
  background-color: var(--bg);
  background-image: radial-gradient(rgba(255, 255, 255, 0.035) 1px, transparent 1px);
  background-size: 28px 28px;
  display: flex;
  align-items: center;
  position: relative;
  overflow: hidden;
  padding: calc(var(--nav-h) + 40px) 0 80px;
}

.hero__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
  width: 100%;
}

.hero__content {
  max-width: 600px;
}

.hero__tag {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 24px;
  animation: fadeUp 0.6s ease both 0.1s;
}
.hero__tag-line {
  display: block;
  width: 30px;
  height: 1px;
  background: var(--red);
  flex-shrink: 0;
  transform-origin: left;
  animation: lineIn 0.5s ease both 0.1s;
}
.hero__tag span:last-child {
  font-size: 13px;
  color: var(--red);
  letter-spacing: 0.24em;
  font-family: var(--font-disp);
}

.hero__headline {
  font-size: clamp(38px, 5.2vw, 62px);
  font-weight: 700;
  line-height: 1.1;
  letter-spacing: -0.025em;
  margin: 0 0 22px;
}
.hero__headline--white {
  display: block;
  color: var(--text);
  animation: fadeUp 0.65s ease both 0.25s;
}
.hero__headline--red {
  display: block;
  color: var(--red);
  animation: fadeUp 0.65s ease both 0.4s;
}

.hero__sub {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 2.1;
  max-width: 360px;
  margin: 0 0 40px;
  animation: fadeUp 0.6s ease both 0.55s;
}

.hero__actions {
  display: flex;
  gap: 24px;
  align-items: center;
  flex-wrap: wrap;
  animation: fadeUp 0.6s ease both 0.7s;
}

/* =============================================
   SECTION DIVIDER
============================================= */
.section-divider {
  background: var(--bg-alt);
  padding: 28px 0;
}

.section-divider__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
  display: flex;
  align-items: center;
  gap: 20px;
}

.section-divider__line {
  flex: 1;
  height: 1px;
  background: var(--border);
}

.section-divider__mark {
  width: 22px;
  height: 22px;
  object-fit: contain;
  mix-blend-mode: screen;
  opacity: 0.35;
  flex-shrink: 0;
  transition: opacity 0.3s ease;
}

.section-divider:hover .section-divider__mark {
  opacity: 0.7;
}

/* Background ghost mark — screen blend で黒が透明になり赤Kだけ残る */
.hero__bg-mark {
  position: absolute;
  right: -40px;
  top: 50%;
  transform: translateY(-50%);
  width: min(540px, 48vw);
  mix-blend-mode: screen;
  pointer-events: none;
  user-select: none;
  animation: kPulse 4s ease-in-out infinite;
}
.hero__bg-mark img { width: 100%; }

/* 右端の縦ライン装飾 */
.hero__vline {
  position: absolute;
  top: 0;
  right: var(--pad-x);
  bottom: 0;
  width: 1px;
  background: rgba(232, 0, 59, 0.07);
  pointer-events: none;
}

/* Scroll indicator */
.hero__scroll-hint {
  position: absolute;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
}
.hero__scroll-hint span {
  font-size: 9px;
  letter-spacing: 0.22em;
  color: #2a2a2a;
  font-family: var(--font-disp);
}
.hero__scroll-line {
  width: 1px;
  height: 36px;
  background: linear-gradient(to bottom, #2a2a2a, transparent);
  animation: scrollPulse 2.2s ease-in-out infinite;
}
@keyframes scrollPulse {
  0%, 100% { opacity: 0; transform: scaleY(0.3); transform-origin: top; }
  50%       { opacity: 1; transform: scaleY(1);   transform-origin: top; }
}


/* =============================================
   SECTION — shared
============================================= */
.section {
  padding: 100px 0;
}

.section__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
}

.section__header {
  margin-bottom: 60px;
}

.section__label {
  display: block;
  font-size: 13px;
  font-family: var(--font-disp);
  color: var(--red);
  letter-spacing: 0.22em;
  margin-bottom: 12px;
}

.section__title {
  font-size: clamp(28px, 3.5vw, 44px);
  font-weight: 700;
  color: var(--text);
  letter-spacing: -0.015em;
  line-height: 1.1;
}

.section__desc {
  font-size: 14px;
  color: var(--text-muted);
  line-height: 2;
  margin-top: 18px;
}

/* =============================================
   ABOUT
============================================= */
.about {
  background: var(--bg-alt);
}

.about__content {
  display: grid;
  grid-template-columns: 1fr 260px;
  gap: 80px;
  align-items: start;
}

.about__text p {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 2.2;
  margin-bottom: 22px;
}

.about__tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
  margin-top: 32px;
}

.tag {
  font-size: 11px;
  color: var(--red);
  border: 1px solid var(--border-red);
  padding: 5px 14px;
  letter-spacing: 0.06em;
  transition: background 0.2s ease;
}
.tag:hover {
  background: rgba(232, 0, 59, 0.06);
}

.about__image {
  position: relative;
}
.about__image::before {
  content: '';
  position: absolute;
  inset: -6px;
  border: 1px solid var(--border-red);
  pointer-events: none;
}
.about__image img {
  width: 100%;
  display: block;
}

/* =============================================
   LESSON
============================================= */
.lesson {
  background: var(--bg);
}

.lesson__grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1px;
  background: var(--border);
  margin-bottom: 64px;
}

.lesson__card {
  background: var(--bg);
  padding: 48px 40px;
  transition: background 0.25s ease;
  position: relative;
  overflow: hidden;
}
.lesson__card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  height: 2px;
  width: 0;
  background: var(--red);
  transition: width 0.4s ease;
}
.lesson__card:hover {
  background: var(--bg-alt);
}
.lesson__card:hover::before {
  width: 100%;
}

.lesson__card-number {
  font-family: var(--font-disp);
  font-size: 14px;
  color: var(--red);
  letter-spacing: 0.18em;
  margin-bottom: 18px;
}

.lesson__card h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 14px;
  letter-spacing: -0.01em;
}

.lesson__card p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 2;
}

/* Info table */
.lesson__info {
  border-top: 1px solid var(--border);
}

.lesson__info-item {
  display: grid;
  grid-template-columns: 80px 1fr;
  gap: 24px;
  padding: 22px 0;
  border-bottom: 1px solid var(--border);
  align-items: baseline;
}

.lesson__info-label {
  font-size: 13px;
  font-family: var(--font-disp);
  color: var(--red);
  letter-spacing: 0.14em;
  padding-top: 2px;
}

.lesson__info-value {
  font-size: 14px;
  color: var(--text-sub);
  line-height: 1.8;
}

/* =============================================
   WORKS
============================================= */
.works {
  background: var(--bg-alt);
}

.works__grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 0 40px;
}

.works__item {
  padding: 44px 0;
  border-top: 1px solid var(--border);
  position: relative;
  overflow: hidden;
}
.works__item::before {
  content: '';
  position: absolute;
  top: -1px;
  left: 0;
  height: 2px;
  width: 0;
  background: var(--red);
  transition: width 0.4s ease;
}
.works__item:hover::before {
  width: 100%;
}

.works__item-num {
  font-family: var(--font-disp);
  font-size: 13px;
  color: var(--red);
  letter-spacing: 0.18em;
  margin-bottom: 18px;
}

.works__item h3 {
  font-size: 18px;
  font-weight: 700;
  color: var(--text);
  margin: 0 0 14px;
  letter-spacing: -0.01em;
}

.works__item p {
  font-size: 13px;
  color: var(--text-muted);
  line-height: 2;
}

/* =============================================
   CONTACT
============================================= */
.contact {
  background: var(--bg);
}

.contact__form {
  max-width: 580px;
  margin: 0 auto;
}

.form__group {
  margin-bottom: 28px;
}

.form__group label {
  display: block;
  font-size: 11px;
  color: #666;
  letter-spacing: 0.08em;
  margin-bottom: 10px;
}

.required {
  color: var(--red);
}

.form__group input,
.form__group textarea {
  width: 100%;
  background: var(--bg-alt);
  border: 1px solid rgba(255, 255, 255, 0.07);
  color: var(--text);
  padding: 13px 16px;
  font-size: 14px;
  font-family: 'Noto Sans JP', sans-serif;
  transition: border-color 0.2s ease;
  outline: none;
  appearance: none;
}

.form__group input:focus,
.form__group textarea:focus,
.form__group select:focus {
  border-color: var(--red);
}

.form__group input::placeholder,
.form__group textarea::placeholder {
  color: #2e2e2e;
}

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

/* Select custom */
.select-wrap {
  position: relative;
}
.select-wrap::after {
  content: '';
  position: absolute;
  right: 16px;
  top: 50%;
  transform: translateY(-50%);
  width: 6px;
  height: 6px;
  border-right: 1px solid #444;
  border-bottom: 1px solid #444;
  transform: translateY(-60%) rotate(45deg);
  pointer-events: none;
}

.form__group select {
  width: 100%;
  background: var(--bg-alt);
  border: 1px solid rgba(255, 255, 255, 0.07);
  color: var(--text);
  padding: 13px 16px;
  font-size: 14px;
  font-family: 'Noto Sans JP', sans-serif;
  appearance: none;
  cursor: pointer;
  outline: none;
  transition: border-color 0.2s ease;
}

/* Form success */
.form-success {
  text-align: center;
  padding: 80px 20px;
  max-width: 580px;
  margin: 0 auto;
}
.form-success p {
  font-size: 15px;
  color: var(--text-sub);
  line-height: 2.2;
}

/* =============================================
   FOOTER
============================================= */
.footer {
  background: #020202;
  border-top: 1px solid var(--border);
  padding: 36px 0;
}

.footer__inner {
  max-width: var(--max-w);
  margin: 0 auto;
  padding: 0 var(--pad-x);
  display: flex;
  justify-content: space-between;
  align-items: center;
}

.footer__logo {
  display: flex;
  align-items: center;
  gap: 10px;
  transition: opacity 0.2s ease;
}

.footer__logo-mark {
  width: 28px;
  height: 28px;
  object-fit: contain;
  mix-blend-mode: screen;
  opacity: 0.5;
  transition: opacity 0.2s ease;
}
.footer__logo:hover .footer__logo-mark {
  opacity: 0.85;
}

.footer__copy {
  font-size: 11px;
  color: #2a2a2a;
  letter-spacing: 0.06em;
}

/* =============================================
   RESPONSIVE — Tablet (≤900px)
============================================= */
@media (max-width: 900px) {
  :root {
    --pad-x: 28px;
  }

  /* Hero */
  .hero__bg-mark {
    width: min(380px, 55vw);
    opacity: 0.12;
  }

  /* About */
  .about__content {
    grid-template-columns: 1fr;
    gap: 48px;
  }

  .about__image {
    max-width: 220px;
    margin: 0 auto;
  }

  /* Lesson */
  .lesson__grid {
    grid-template-columns: 1fr;
  }

  /* Works */
  .works__grid {
    grid-template-columns: 1fr;
    gap: 0;
  }
}

/* =============================================
   RESPONSIVE — Mobile (≤640px)
============================================= */
@media (max-width: 640px) {
  :root {
    --pad-x:  20px;
    --nav-h:  60px;
  }

  /* モバイルではbackdrop-filterを使わない
     理由: backdrop-filterはSafari/iOSで新しいstacking contextを生成し
           子要素のposition:fixedがviewportではなくnav(60px)基準になってしまう */
  .nav {
    background: rgba(7, 7, 7, 0.96);
    border-bottom-color: var(--border);
  }

  .nav.scrolled {
    background: rgba(7, 7, 7, 0.98);
    backdrop-filter: none;
    -webkit-backdrop-filter: none;
  }

  /* ---- Section 共通 ---- */
  .section {
    padding: 64px 0;
  }

  .section__header {
    margin-bottom: 36px;
  }

  .section__title {
    font-size: clamp(24px, 7vw, 32px);
  }

  /* ---- Nav ---- */
  .nav__inner {
    height: var(--nav-h);
    padding: 0 var(--pad-x);
  }

  .nav__logo-mark {
    width: 28px;
    height: 28px;
  }

  .nav__hamburger {
    display: flex;
  }

  .nav__links {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    /* iOS Safariはdvhをサポートしている場合にdynamic viewport heightを使う */
    height: 100dvh;
    background: rgba(7, 7, 7, 0.98);
    flex-direction: column;
    justify-content: center;
    gap: 40px;
    transform: translateX(100%);
    transition: transform 0.35s cubic-bezier(0.77, 0, 0.18, 1);
    /* backdrop-filterはここでは使わない（stacking context問題を避けるため） */
  }

  .nav__links.open {
    transform: translateX(0);
  }

  .nav__link {
    font-size: 22px;
    color: var(--text);
    letter-spacing: 0.14em;
    text-align: center;
  }

  .nav__cta {
    font-size: 18px;
    padding: 10px 32px;
  }

  /* ---- Hero ---- */
  .hero {
    /* コンテンツをヒーロー下部に配置
       → ナビロゴ（上部）との被りを構造的に解消
       → 上部の余白にKマークが映える */
    align-items: flex-end;
    min-height: 100svh; /* iOS SafariでもUI分を正確に除いた高さ */
    padding-top: var(--nav-h);
    padding-bottom: 64px;
    background-size: 20px 20px;
  }

  .hero__tag span:last-child {
    font-size: 11px;
  }

  .hero__headline {
    font-size: clamp(32px, 9.5vw, 44px);
    margin-bottom: 18px;
  }

  .hero__sub {
    font-size: 12.5px;
    line-height: 2;
    margin-bottom: 32px;
  }

  .hero__sub br {
    display: none;
  }

  .hero__actions {
    flex-direction: column;
    align-items: flex-start;
    gap: 14px;
  }

  .btn--primary {
    width: 100%;
    justify-content: center;
    padding: 14px 20px;
    font-size: 13px;
  }

  .hero__vline {
    display: none;
  }

  .hero__bg-mark {
    width: 72vw;
    right: -10px;
    top: 15%;           /* 上部エリアに浮かべる */
    transform: none;    /* translateY(-50%)をリセット */
    opacity: 0.11;
  }

  .hero__scroll-hint {
    display: none;
  }

  /* ---- Marquee ---- */
  .marquee__item {
    font-size: 11px;
    padding: 0 20px;
  }

  /* ---- About ---- */
  .about__content {
    grid-template-columns: 1fr;
    gap: 36px;
  }

  .about__text p {
    font-size: 13.5px;
  }

  .about__image {
    max-width: 180px;
    margin: 0 auto;
  }

  .about__image::before {
    inset: -4px;
  }

  .about__tags {
    gap: 6px;
    margin-top: 24px;
  }

  .tag {
    font-size: 10.5px;
    padding: 4px 10px;
  }

  /* ---- Lesson ---- */
  .lesson__grid {
    grid-template-columns: 1fr;
  }

  .lesson__card {
    padding: 32px 24px;
  }

  .lesson__card h3 {
    font-size: 16px;
  }

  .lesson__card p {
    font-size: 12.5px;
  }

  .lesson__info-item {
    grid-template-columns: 64px 1fr;
    gap: 12px;
    padding: 18px 0;
  }

  .lesson__info-value {
    font-size: 13px;
  }

  /* ---- Works ---- */
  .works__grid {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .works__item {
    padding: 32px 0;
  }

  .works__item h3 {
    font-size: 16px;
  }

  .works__item p {
    font-size: 12.5px;
  }

  /* ---- Contact ---- */
  .contact__form {
    max-width: 100%;
  }

  .form__group {
    margin-bottom: 20px;
  }

  .form__group label {
    font-size: 12px;
    margin-bottom: 8px;
  }

  .form__group input,
  .form__group select,
  .form__group textarea {
    font-size: 16px; /* iOS zoom防止 */
    padding: 12px 14px;
  }

  .section__desc {
    font-size: 13px;
  }

  /* ---- Footer ---- */
  .footer {
    padding: 28px 0;
  }

  .footer__inner {
    flex-direction: column;
    gap: 16px;
    text-align: center;
  }

  .footer__logo-mark {
    width: 24px;
    height: 24px;
  }
}

/* =============================================
   RESPONSIVE — Extra small (≤375px)
============================================= */
@media (max-width: 375px) {
  :root {
    --pad-x: 16px;
  }

  .hero__headline {
    font-size: 30px;
  }

  /* 場所などの長いテキストで折り返しやすくする */
  .lesson__info-item {
    grid-template-columns: 1fr;
    gap: 4px;
    padding: 14px 0;
  }

  .lesson__info-label {
    font-size: 11px;
  }

  .nav__link {
    font-size: 18px;
  }
}