/* ========================================
   株式会社A STUDIO - Corporate Site
   ampersand-inspired design
   ======================================== */

*,
*::before,
*::after {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

:root {
  --white: #ffffff;
  --black: #0d0d0d;
  --dark: #1a1a2e;
  --gray-50: #f7f8fa;
  --gray-100: #eef0f4;
  --gray-300: #c4c8d0;
  --gray-400: #aaafb6;
  --gray-600: #6b7280;
  --gray-800: #2d2d3a;
  --purple: #5636d1;
  --purple-light: #7c5ce7;
  --violet: #9b51e0;
  --pink: #e2498a;
  --font-en: 'Karla', sans-serif;
  --font-ja: 'Noto Sans JP', sans-serif;
  --ease: cubic-bezier(0.23, 1, 0.32, 1);
}

html {
  scroll-behavior: smooth;
  scroll-padding-top: 80px;
}

body {
  font-family: var(--font-ja);
  background: var(--white);
  color: var(--black);
  line-height: 1.8;
  font-size: 15px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

a { color: inherit; text-decoration: none; }
img { max-width: 100%; }

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ── Header ── */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  z-index: 100;
  transition: transform 0.5s var(--ease), background 0.4s;
}

.header.hidden {
  transform: translateY(-100%);
}

.header.solid {
  background: rgba(255,255,255,0.92);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--gray-100);
}

.header-inner {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 40px;
  height: 80px;
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.logo {
  font-family: var(--font-en);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: 0.08em;
  color: var(--white);
  transition: color 0.4s;
}

.header.solid .logo {
  color: var(--black);
}

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

.nav-link {
  font-family: var(--font-en);
  font-size: 13px;
  font-weight: 500;
  letter-spacing: 0.06em;
  color: rgba(255,255,255,0.6);
  transition: color 0.3s;
}

.nav-link:hover {
  color: rgba(255,255,255,1);
}

.header.solid .nav-link {
  color: var(--gray-400);
}

.header.solid .nav-link:hover {
  color: var(--black);
}

/* Hamburger */
.hamburger {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
  width: 40px;
  height: 40px;
  position: relative;
}

.hamburger span {
  position: absolute;
  left: 8px;
  width: 24px;
  height: 1.5px;
  background: var(--white);
  transition: transform 0.4s var(--ease), opacity 0.3s;
}

.header.solid .hamburger span {
  background: var(--black);
}

.hamburger span:first-child { top: 16px; }
.hamburger span:last-child { top: 24px; }

.hamburger.active span:first-child {
  transform: translateY(4px) rotate(45deg);
}

.hamburger.active span:last-child {
  transform: translateY(-4px) rotate(-45deg);
}

/* ── Hero ── */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--dark);
  overflow: hidden;
  padding: 0 40px;
}

.hero-bg {
  position: absolute;
  inset: 0;
  z-index: 0;
}

.hero-orb {
  position: absolute;
  border-radius: 50%;
  filter: blur(100px);
}

.hero-orb-1 {
  width: 500px;
  height: 500px;
  background: var(--purple);
  top: -10%;
  right: -5%;
  opacity: 0.25;
}

.hero-orb-2 {
  width: 400px;
  height: 400px;
  background: var(--violet);
  bottom: -15%;
  left: 10%;
  opacity: 0.15;
}

.hero-orb-3 {
  width: 300px;
  height: 300px;
  background: var(--pink);
  top: 40%;
  left: -10%;
  opacity: 0.1;
}

.hero-content {
  position: relative;
  z-index: 1;
  text-align: center;
}

.hero-copy {
  margin-bottom: 32px;
}

.hero-line {
  font-size: clamp(36px, 6vw, 72px);
  font-weight: 700;
  line-height: 1.3;
  letter-spacing: -0.03em;
  color: var(--white);
  overflow: hidden;
}

.reveal {
  display: inline-block;
  overflow: hidden;
}

.reveal-inner {
  display: inline-block;
  transform: translateY(110%);
  animation: revealUp 1s var(--ease) forwards;
}

.hero-line-1 .reveal-inner { animation-delay: 0.3s; }
.hero-line-2 .reveal-inner { animation-delay: 0.6s; }

@keyframes revealUp {
  to { transform: translateY(0); }
}

.hero-sub {
  font-size: clamp(14px, 1.8vw, 17px);
  font-weight: 300;
  color: rgba(255,255,255,0.45);
  letter-spacing: 0.04em;
  opacity: 0;
  animation: fadeIn 1s ease 1.2s forwards;
}

@keyframes fadeIn {
  to { opacity: 1; }
}

/* Scroll indicator */
.hero-scroll {
  position: absolute;
  bottom: 40px;
  left: 50%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 12px;
  z-index: 1;
}

.hero-scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, rgba(255,255,255,0.4), transparent);
  animation: scrollPulse 2s ease-in-out infinite;
}

@keyframes scrollPulse {
  0%, 100% { opacity: 1; transform: scaleY(1); }
  50% { opacity: 0.3; transform: scaleY(0.6); }
}

.hero-scroll-text {
  font-family: var(--font-en);
  font-size: 11px;
  letter-spacing: 0.15em;
  color: rgba(255,255,255,0.3);
}

/* ── Section Common ── */
.section {
  padding: 140px 0;
}

.section-gray {
  background: var(--gray-50);
}

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

.section-header {
  margin-bottom: 80px;
}

.section-label {
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--purple);
  margin-bottom: 20px;
}

.section-label-light {
  color: var(--purple-light);
}

.section-title-lg {
  font-size: clamp(28px, 4.5vw, 48px);
  font-weight: 700;
  line-height: 1.4;
  letter-spacing: -0.02em;
}

.section-title-light {
  color: var(--white);
}

.section-desc {
  margin-top: 20px;
  font-size: 15px;
  color: var(--gray-600);
  line-height: 2;
}

/* ── Mission ── */
.mission-content {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 40px;
}

.mission-block {
  padding: 48px 40px;
  border: 1px solid var(--gray-100);
  border-radius: 4px;
  transition: border-color 0.4s, box-shadow 0.4s;
}

.mission-block:hover {
  border-color: var(--gray-300);
  box-shadow: 0 8px 40px rgba(0,0,0,0.04);
}

.mission-tag {
  font-family: var(--font-en);
  font-size: 11px;
  font-weight: 700;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--purple);
  display: block;
  margin-bottom: 20px;
}

.mission-text {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 2.2;
}

/* ── Business (Dark) ── */
.biz-list {
  display: flex;
  flex-direction: column;
  gap: 0;
}

.biz-item {
  display: flex;
  gap: 48px;
  padding: 56px 0;
  border-bottom: 1px solid rgba(255,255,255,0.08);
  transition: background 0.4s;
}

.biz-item:first-child {
  border-top: 1px solid rgba(255,255,255,0.08);
}

.biz-item:hover {
  background: rgba(255,255,255,0.02);
}

.biz-num {
  font-family: var(--font-en);
  font-size: 56px;
  font-weight: 700;
  line-height: 1;
  color: var(--purple-light);
  opacity: 0.4;
  flex-shrink: 0;
  width: 100px;
}

.biz-body {
  flex: 1;
}

.biz-title {
  font-size: 22px;
  font-weight: 700;
  margin-bottom: 16px;
  letter-spacing: -0.01em;
}

.biz-desc {
  font-size: 14px;
  color: rgba(255,255,255,0.5);
  line-height: 2;
  margin-bottom: 24px;
}

.biz-tags {
  display: flex;
  flex-wrap: wrap;
  gap: 8px;
}

.biz-tags span {
  font-size: 12px;
  padding: 5px 16px;
  border: 1px solid rgba(255,255,255,0.12);
  border-radius: 100px;
  color: rgba(255,255,255,0.5);
  transition: border-color 0.3s, color 0.3s;
}

.biz-tags span:hover {
  border-color: var(--purple-light);
  color: var(--purple-light);
}

/* ── Message ── */
.msg-wrap {
  max-width: 720px;
  margin: 0 auto;
}

.msg-body p {
  font-size: 15px;
  color: var(--gray-600);
  line-height: 2.4;
  margin-bottom: 24px;
}

.msg-body p:last-child {
  margin-bottom: 0;
}

.msg-author {
  margin-top: 48px;
  padding-top: 32px;
  border-top: 1px solid var(--gray-100);
  display: flex;
  align-items: baseline;
  gap: 16px;
  justify-content: flex-end;
}

.msg-author-role {
  font-size: 13px;
  color: var(--gray-400);
}

.msg-author-name {
  font-size: 20px;
  font-weight: 700;
  letter-spacing: 0.06em;
}

/* ── Company ── */
.company-wrap {
  max-width: 720px;
  margin: 0 auto;
}

.company-table {
  width: 100%;
  border-collapse: collapse;
}

.company-table tr {
  border-bottom: 1px solid var(--gray-100);
}

.company-table th,
.company-table td {
  padding: 24px 0;
  font-size: 14px;
  text-align: left;
  vertical-align: top;
}

.company-table th {
  width: 120px;
  color: var(--gray-400);
  font-weight: 500;
  letter-spacing: 0.04em;
}

.company-table td {
  color: var(--black);
  font-weight: 400;
}

.company-table td a {
  color: var(--purple);
  transition: opacity 0.3s;
}

.company-table td a:hover {
  opacity: 0.7;
}

/* Access */
.access {
  max-width: 720px;
  margin: 64px auto 0;
}

.access-label {
  font-family: var(--font-en);
  font-size: 12px;
  font-weight: 600;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--purple);
  margin-bottom: 24px;
}

.access-map {
  overflow: hidden;
  border-radius: 4px;
  margin-bottom: 16px;
  border: 1px solid var(--gray-100);
}

.access-text {
  font-size: 14px;
  color: var(--gray-600);
}

.access-sub {
  font-size: 13px;
  color: var(--gray-400);
  margin-top: 4px;
}

/* ── Contact ── */
.form {
  max-width: 720px;
  margin: 0 auto;
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 24px;
}

.form-group {
  margin-bottom: 28px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  color: var(--gray-600);
  margin-bottom: 10px;
  letter-spacing: 0.02em;
}

.req {
  color: var(--purple);
}

.form-group input,
.form-group textarea,
.form-group select {
  width: 100%;
  padding: 14px 0;
  background: transparent;
  border: none;
  border-bottom: 1px solid var(--gray-300);
  color: var(--black);
  font-family: var(--font-ja);
  font-size: 15px;
  outline: none;
  transition: border-color 0.3s;
  border-radius: 0;
}

.form-group select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='12' height='12' viewBox='0 0 12 12'%3E%3Cpath d='M2 4l4 4 4-4' fill='none' stroke='%23aaafb6' stroke-width='1.5'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 0 center;
  cursor: pointer;
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--gray-300);
}

.form-group input:focus,
.form-group textarea:focus,
.form-group select:focus {
  border-color: var(--purple);
}

.form-group textarea {
  resize: vertical;
  min-height: 100px;
}

.form-btn {
  display: inline-flex;
  align-items: center;
  gap: 12px;
  padding: 18px 48px;
  background: var(--purple);
  color: var(--white);
  font-family: var(--font-ja);
  font-size: 14px;
  font-weight: 500;
  letter-spacing: 0.06em;
  border: none;
  border-radius: 0;
  cursor: pointer;
  transition: background 0.3s, transform 0.2s;
  margin-top: 8px;
}

.form-btn:hover {
  background: var(--purple-light);
  transform: translateY(-1px);
}

.form-btn svg {
  transition: transform 0.3s;
}

.form-btn:hover svg {
  transform: translateX(4px);
}

.form-status {
  margin-top: 20px;
  font-size: 14px;
}

.form-status.success { color: #16a34a; }
.form-status.error { color: #dc2626; }

/* ── Footer ── */
.footer {
  background: var(--black);
  color: var(--white);
  padding: 64px 0 40px;
}

.footer-top {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  padding-bottom: 48px;
  border-bottom: 1px solid rgba(255,255,255,0.08);
}

.footer-logo {
  font-family: var(--font-en);
  font-weight: 700;
  font-size: 20px;
  letter-spacing: 0.08em;
  margin-bottom: 8px;
}

.footer-tagline {
  font-size: 13px;
  color: rgba(255,255,255,0.3);
}

.footer-nav {
  display: flex;
  gap: 28px;
}

.footer-nav a {
  font-family: var(--font-en);
  font-size: 13px;
  color: rgba(255,255,255,0.35);
  letter-spacing: 0.04em;
  transition: color 0.3s;
}

.footer-nav a:hover {
  color: var(--white);
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding-top: 24px;
}

.footer-info {
  font-size: 12px;
  color: rgba(255,255,255,0.2);
}

.footer-copy {
  font-family: var(--font-en);
  font-size: 12px;
  color: rgba(255,255,255,0.2);
}

/* ── Animations ── */
.fade-up {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.9s var(--ease), transform 0.9s var(--ease);
}

.fade-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .container { padding: 0 24px; }
  .header-inner { padding: 0 24px; }

  .nav {
    display: none;
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background: rgba(26,26,46,0.97);
    backdrop-filter: blur(20px);
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: 28px;
    z-index: 99;
  }

  .nav.open {
    display: flex;
  }

  .nav.open .nav-link {
    font-size: 18px;
    color: rgba(255,255,255,0.7);
  }

  .hamburger {
    display: block;
    z-index: 101;
  }

  .hero {
    min-height: 100vh;
    min-height: 100dvh;
    padding: 0 24px;
  }

  .hero-line {
    font-size: 32px;
  }

  .section {
    padding: 100px 0;
  }

  .section-header {
    margin-bottom: 56px;
  }

  .mission-content {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .mission-block {
    padding: 32px 24px;
  }

  .biz-item {
    flex-direction: column;
    gap: 16px;
    padding: 40px 0;
  }

  .biz-num {
    font-size: 40px;
    width: auto;
  }

  .form-row {
    grid-template-columns: 1fr;
    gap: 0;
  }

  .msg-author {
    flex-direction: column;
    gap: 4px;
    align-items: flex-end;
  }

  .footer-top {
    flex-direction: column;
    gap: 32px;
  }

  .footer-nav {
    flex-wrap: wrap;
    gap: 16px;
  }

  .footer-bottom {
    flex-direction: column;
    gap: 8px;
    text-align: center;
  }

  .company-table th {
    width: 90px;
    font-size: 13px;
  }

  .hero-orb-1 { width: 300px; height: 300px; }
  .hero-orb-2 { width: 250px; height: 250px; }
  .hero-orb-3 { width: 200px; height: 200px; }
}