/* ============================================
   birdwing technologies - Corporate Site
   ============================================ */

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: "Helvetica Neue", Arial, "Hiragino Kaku Gothic ProN", "Hiragino Sans", Meiryo, sans-serif;
  color: #333;
  line-height: 1.8;
  font-size: 16px;
  background: #fff;
}

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

ul {
  list-style: none;
}

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

.container {
  max-width: 1080px;
  margin: 0 auto;
  padding: 0 24px;
}

.sp-only {
  display: none;
}

/* --- Header --- */
.header {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  background: rgba(255, 255, 255, 0.97);
  backdrop-filter: blur(8px);
  z-index: 1000;
  border-bottom: 1px solid #e8e8e8;
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 64px;
}

.logo {
  font-size: 1.2rem;
  font-weight: 700;
  color: #1a5276;
  letter-spacing: 0.02em;
}

.nav-toggle {
  display: none;
  background: none;
  border: none;
  font-size: 1.5rem;
  cursor: pointer;
  color: #333;
}

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

.nav-list a {
  font-size: 0.9rem;
  font-weight: 500;
  color: #555;
  transition: color 0.2s;
}

.nav-list a:hover {
  color: #1a5276;
}

/* --- Hero --- */
.hero {
  position: relative;
  display: flex;
  align-items: center;
  min-height: 600px;
  padding: 120px 0 80px;
  background: linear-gradient(135deg, #1a5276 0%, #2e86c1 50%, #48b4e0 100%);
  overflow: hidden;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse at 20% 50%, rgba(255,255,255,0.08) 0%, transparent 60%),
    radial-gradient(ellipse at 80% 20%, rgba(255,255,255,0.05) 0%, transparent 50%);
}

.hero-content {
  position: relative;
  z-index: 1;
  color: #fff;
}

.hero-content h1 {
  font-size: 2.5rem;
  font-weight: 700;
  line-height: 1.5;
  margin-bottom: 24px;
  letter-spacing: 0.02em;
}

.hero-content p {
  font-size: 1.15rem;
  margin-bottom: 40px;
  opacity: 0.92;
  line-height: 1.9;
}

/* --- Buttons --- */
.btn {
  display: inline-block;
  padding: 14px 40px;
  border-radius: 4px;
  font-size: 1rem;
  font-weight: 600;
  cursor: pointer;
  border: none;
  transition: background 0.2s, transform 0.15s;
}

.btn-primary {
  background: #fff;
  color: #1a5276;
}

.btn-primary:hover {
  background: #e8f4fd;
  transform: translateY(-1px);
}

/* --- Section Common --- */
.section {
  padding: 96px 0;
}

.section-alt {
  background: #f7f9fb;
}

.section-title {
  font-size: 1.8rem;
  font-weight: 700;
  text-align: center;
  margin-bottom: 16px;
  color: #1a5276;
  letter-spacing: 0.02em;
}

.section-title::after {
  content: "";
  display: block;
  width: 48px;
  height: 3px;
  background: #2e86c1;
  margin: 16px auto 0;
  border-radius: 2px;
}

.section-lead {
  text-align: center;
  max-width: 700px;
  margin: 24px auto 48px;
  color: #555;
  line-height: 1.9;
}

/* --- About --- */
.about-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 32px;
}

.about-card {
  text-align: center;
  padding: 40px 24px;
  border-radius: 8px;
  background: #f7f9fb;
  transition: box-shadow 0.2s;
}

.about-card:hover {
  box-shadow: 0 4px 20px rgba(0, 0, 0, 0.06);
}

.about-icon {
  font-size: 2.2rem;
  margin-bottom: 16px;
  color: #2e86c1;
}

.about-card h3 {
  font-size: 1.1rem;
  margin-bottom: 12px;
  color: #1a5276;
}

.about-card p {
  font-size: 0.95rem;
  color: #666;
}

/* --- Services --- */
.services-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 40px;
}

.service-card {
  background: #fff;
  padding: 48px 36px;
  border-radius: 8px;
  box-shadow: 0 2px 12px rgba(0, 0, 0, 0.04);
  border: 1px solid #eef2f5;
}

.service-number {
  font-size: 2rem;
  font-weight: 700;
  color: #2e86c1;
  opacity: 0.5;
  margin-bottom: 12px;
}

.service-card h3 {
  font-size: 1.25rem;
  color: #1a5276;
  margin-bottom: 16px;
}

.service-card p {
  font-size: 0.95rem;
  color: #555;
  margin-bottom: 20px;
}

.service-list {
  padding-left: 0;
}

.service-list li {
  position: relative;
  padding-left: 20px;
  margin-bottom: 8px;
  font-size: 0.93rem;
  color: #555;
}

.service-list li::before {
  content: "";
  position: absolute;
  left: 0;
  top: 10px;
  width: 8px;
  height: 8px;
  background: #2e86c1;
  border-radius: 50%;
}

/* --- Company Table --- */
.company-table {
  width: 100%;
  max-width: 760px;
  margin: 48px auto 0;
  border-collapse: collapse;
}

.company-table tr {
  border-bottom: 1px solid #e8e8e8;
}

.company-table th,
.company-table td {
  padding: 20px 16px;
  text-align: left;
  vertical-align: top;
  font-size: 0.95rem;
}

.company-table th {
  width: 160px;
  font-weight: 600;
  color: #1a5276;
  background: #f7f9fb;
}

.placeholder {
  color: #b0b0b0;
  font-style: italic;
}

/* --- Contact Form --- */
.contact-form {
  max-width: 640px;
  margin: 0 auto;
}

.form-group {
  margin-bottom: 24px;
}

.form-group label {
  display: block;
  font-size: 0.93rem;
  font-weight: 600;
  margin-bottom: 8px;
  color: #333;
}

.required {
  color: #e74c3c;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  border: 1px solid #d0d0d0;
  border-radius: 4px;
  font-size: 1rem;
  font-family: inherit;
  transition: border-color 0.2s;
  background: #fff;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: #2e86c1;
  box-shadow: 0 0 0 3px rgba(46, 134, 193, 0.12);
}

.form-submit {
  text-align: center;
  margin-top: 32px;
}

.form-submit .btn-primary {
  background: #1a5276;
  color: #fff;
  padding: 16px 56px;
}

.form-submit .btn-primary:hover {
  background: #2e86c1;
}

/* --- Footer --- */
.footer {
  background: #1a2634;
  color: #ccc;
  padding: 48px 0 32px;
}

.footer-inner {
  display: flex;
  justify-content: space-between;
  align-items: flex-start;
  margin-bottom: 32px;
}

.footer-logo {
  font-size: 1rem;
  font-weight: 600;
  color: #fff;
  margin-bottom: 8px;
}

.footer-address {
  font-size: 0.85rem;
}

.footer-nav {
  display: flex;
  gap: 24px;
}

.footer-nav a {
  font-size: 0.85rem;
  color: #aaa;
  transition: color 0.2s;
}

.footer-nav a:hover {
  color: #fff;
}

.copyright {
  text-align: center;
  font-size: 0.8rem;
  color: #777;
  border-top: 1px solid #2a3a4a;
  padding-top: 24px;
}

/* ============================================
   Responsive
   ============================================ */
@media (max-width: 768px) {
  .sp-only {
    display: inline;
  }

  /* Header */
  .nav-toggle {
    display: block;
  }

  .nav-list {
    display: none;
    flex-direction: column;
    position: absolute;
    top: 64px;
    left: 0;
    width: 100%;
    background: #fff;
    border-bottom: 1px solid #e8e8e8;
    padding: 16px 24px;
    gap: 0;
  }

  .nav-list.open {
    display: flex;
  }

  .nav-list li {
    padding: 12px 0;
    border-bottom: 1px solid #f0f0f0;
  }

  .nav-list li:last-child {
    border-bottom: none;
  }

  /* Hero */
  .hero {
    min-height: 480px;
    padding: 100px 0 60px;
  }

  .hero-content h1 {
    font-size: 1.7rem;
  }

  .hero-content p {
    font-size: 1rem;
  }

  /* Sections */
  .section {
    padding: 64px 0;
  }

  .section-title {
    font-size: 1.5rem;
  }

  /* About */
  .about-grid {
    grid-template-columns: 1fr;
    gap: 20px;
  }

  /* Services */
  .services-grid {
    grid-template-columns: 1fr;
    gap: 24px;
  }

  .service-card {
    padding: 32px 24px;
  }

  /* Company Table */
  .company-table th {
    width: 120px;
    font-size: 0.85rem;
  }

  .company-table td {
    font-size: 0.9rem;
  }

  /* Footer */
  .footer-inner {
    flex-direction: column;
    gap: 24px;
  }

  .footer-nav {
    flex-direction: column;
    gap: 12px;
  }
}