/* ============================================
   平成システム株式会社 — style.css
   ============================================ */

/* --- CSS Variables --- */
:root {
  --color-teal:       #1a454c;
  --color-teal-sub:   #4a7a80;
  --color-teal-light: #d0e8ea;
  --color-teal-bg:    #f5fafb;
  --color-text:       #1a1a18;
  --color-text-sub:   #555555;
  --color-bg:         #ffffff;
}

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

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

body {
  font-family: "DM Sans", "Noto Sans JP", sans-serif;
  font-size: 13px;
  font-weight: 300;
  line-height: 1.9;
  color: var(--color-text);
  background: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

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

ul, ol {
  list-style: none;
}

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

/* --- Container --- */
.container {
  max-width: 1060px;
  margin: 0 auto;
  padding: 0 24px;
}

/* ============================================
   Navigation
   ============================================ */
.nav {
  position: sticky;
  top: 0;
  z-index: 100;
  border-bottom: 1px solid var(--color-teal);
  background: var(--color-bg);
  transition: background .3s, box-shadow .3s;
}

.nav.scrolled {
  background: rgba(255, 255, 255, .97);
  box-shadow: 0 1px 8px rgba(0, 0, 0, .06);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 56px;
}

.nav-logo {
  font-family: "Noto Sans JP", sans-serif;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text);
  white-space: nowrap;
}

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

.nav-links a {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--color-teal);
  transition: color .2s;
}

.nav-links a:hover {
  color: var(--color-text);
}

.nav-links a.active {
  color: var(--color-text);
  font-weight: 500;
}

/* Hamburger */
.nav-hamburger {
  display: none;
  flex-direction: column;
  gap: 5px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 4px;
}

.nav-hamburger span {
  display: block;
  width: 20px;
  height: 1.5px;
  background: var(--color-teal);
  transition: transform .3s, opacity .3s;
}

.nav-hamburger.open span:nth-child(1) {
  transform: translateY(6.5px) rotate(45deg);
}

.nav-hamburger.open span:nth-child(2) {
  opacity: 0;
}

.nav-hamburger.open span:nth-child(3) {
  transform: translateY(-6.5px) rotate(-45deg);
}

/* ============================================
   Page Header (breadcrumb + title)
   ============================================ */
.page-header {
  padding: 32px 0 28px;
  border-bottom: 1px solid var(--color-teal);
}

.breadcrumb {
  font-size: 11px;
  color: var(--color-text-sub);
  margin-bottom: 12px;
}

.breadcrumb a {
  color: var(--color-teal);
}

.breadcrumb span {
  margin: 0 6px;
  color: var(--color-teal-light);
}

.page-title {
  font-size: 28px;
  font-weight: 500;
  color: var(--color-text);
  line-height: 1.4;
}

/* ============================================
   Hero Section (index.html)
   ============================================ */
.hero {
  position: relative;
  padding: 80px 0 64px;
  overflow: hidden;
}

.hero-eyebrow {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--color-teal);
  margin-bottom: 20px;
}

.hero-heading {
  font-family: "Noto Sans JP", sans-serif;
  font-size: 32px;
  font-weight: 300;
  line-height: 1.6;
  margin-bottom: 16px;
  max-width: 600px;
}

.hero-heading strong {
  font-weight: 500;
}

.hero-heading .ai-text {
  color: var(--color-teal-sub);
}

.hero-sub {
  font-size: 12px;
  color: var(--color-teal);
  margin-bottom: 20px;
  letter-spacing: .04em;
}

.hero-body {
  max-width: 520px;
  margin-bottom: 32px;
  color: var(--color-text-sub);
}

.hero-cta {
  display: flex;
  align-items: center;
  gap: 24px;
}

.hero-year {
  position: absolute;
  right: 24px;
  bottom: 24px;
  font-family: "Bebas Neue", sans-serif;
  font-size: 110px;
  color: var(--color-teal-light);
  line-height: 1;
  pointer-events: none;
  user-select: none;
}

/* ============================================
   Buttons
   ============================================ */
.btn-outline {
  display: inline-block;
  padding: 10px 28px;
  border: 1px solid var(--color-teal);
  color: var(--color-teal);
  font-size: 13px;
  font-weight: 400;
  transition: background .2s, color .2s;
}

.btn-outline:hover {
  background: var(--color-teal);
  color: #fff;
}

.btn-solid {
  display: inline-block;
  padding: 10px 28px;
  background: var(--color-teal);
  color: #fff;
  font-size: 13px;
  font-weight: 400;
  border: 1px solid var(--color-teal);
  transition: background .2s, color .2s;
}

.btn-solid:hover {
  background: #153a40;
}

.btn-white {
  display: inline-block;
  padding: 10px 28px;
  background: #fff;
  color: var(--color-teal);
  font-size: 13px;
  font-weight: 400;
  border: none;
  transition: background .2s;
}

.btn-white:hover {
  background: var(--color-teal-bg);
}

.text-link {
  font-size: 13px;
  color: var(--color-teal);
  border-bottom: 1px solid transparent;
  transition: border-color .2s;
}

.text-link:hover {
  border-bottom-color: var(--color-teal);
}

/* ============================================
   Stats Bar
   ============================================ */
.stats {
  border-top: 1px solid var(--color-teal);
  border-bottom: 1px solid var(--color-teal);
}

.stats-inner {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
}

.stat-item {
  text-align: center;
  padding: 28px 16px;
}

.stat-item:not(:last-child) {
  border-right: 1px solid var(--color-teal);
}

.stat-number {
  font-family: "Bebas Neue", sans-serif;
  font-size: 44px;
  line-height: 1;
  color: var(--color-teal);
  margin-bottom: 4px;
}

.stat-label {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .08em;
  color: var(--color-text-sub);
}

/* ============================================
   Section Common
   ============================================ */
.section {
  padding: 64px 0;
}

.section-label {
  display: flex;
  align-items: center;
  gap: 16px;
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .12em;
  color: var(--color-teal);
  margin-bottom: 40px;
}

.section-label::after {
  content: "";
  flex: 1;
  height: 1px;
  background: var(--color-teal-light);
}

.section-heading {
  font-size: 20px;
  font-weight: 500;
  padding-bottom: 12px;
  border-bottom: 2px solid var(--color-teal);
  margin-bottom: 28px;
}

.section-heading-plain {
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 28px;
}

/* ============================================
   Service Cards (index.html)
   ============================================ */
.services-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 1px;
  background: var(--color-teal);
}

.service-card {
  background: var(--color-bg);
  padding: 32px 24px;
  border-top: 2px solid var(--color-teal);
}

.service-card.sub {
  border-top-width: 1px;
}

.service-card .badge {
  display: inline-block;
  font-size: 10px;
  text-transform: uppercase;
  letter-spacing: .08em;
  padding: 3px 10px;
  margin-bottom: 16px;
}

.badge-core {
  background: var(--color-teal);
  color: #fff;
}

.badge-ai {
  background: var(--color-teal-bg);
  color: var(--color-teal-sub);
  border: 1px solid var(--color-teal-light);
}

.service-card h3 {
  font-size: 15px;
  font-weight: 500;
  margin-bottom: 12px;
}

.service-card p {
  color: var(--color-text-sub);
}

/* ============================================
   About Strip (index.html)
   ============================================ */
.about-strip {
  padding: 64px 0;
  border-top: 1px solid var(--color-teal-light);
}

.about-strip-inner {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 48px;
  align-items: start;
}

.about-strip-catch {
  font-family: "Noto Sans JP", sans-serif;
  font-size: 20px;
  font-weight: 500;
  margin-bottom: 16px;
  line-height: 1.6;
}

.about-strip-body {
  color: var(--color-text-sub);
}

/* ============================================
   Tables
   ============================================ */
.info-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
}

.info-table th,
.info-table td {
  padding: 12px 16px;
  border: 1px solid var(--color-teal-light);
  text-align: left;
  vertical-align: top;
}

.info-table th {
  background: var(--color-teal-bg);
  color: var(--color-teal);
  font-weight: 500;
  white-space: nowrap;
  width: 140px;
}

.info-table thead th {
  background: var(--color-teal);
  color: #fff;
  font-weight: 500;
  width: auto;
}

/* ============================================
   Problem Box (service.html)
   ============================================ */
.problem-box {
  background: var(--color-teal-bg);
  border-left: 3px solid var(--color-teal);
  padding: 24px 28px;
  margin: 24px 0;
}

.problem-box h4 {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 12px;
  color: var(--color-teal);
}

.problem-box li {
  padding: 4px 0;
  padding-left: 1em;
  text-indent: -1em;
  color: var(--color-text-sub);
}

.problem-box li::before {
  content: "\30FB";
}

/* ============================================
   Sub Heading (left border)
   ============================================ */
.sub-heading {
  font-size: 13px;
  font-weight: 500;
  padding-left: 12px;
  border-left: 3px solid var(--color-teal);
  margin: 28px 0 12px;
}

/* ============================================
   Content List
   ============================================ */
.content-list li {
  padding: 4px 0;
  padding-left: 1.5em;
  text-indent: -1.5em;
  color: var(--color-text-sub);
}

.content-list li::before {
  content: "\25B6\0020";
  color: var(--color-teal);
  font-size: 10px;
}

/* ============================================
   Tech Tags
   ============================================ */
.tech-tags {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 16px;
  margin: 28px 0;
}

.tech-tag-group {
  border: 1px solid var(--color-teal-light);
  border-top: 2px solid var(--color-teal);
  padding: 16px;
}

.tech-tag-group h4 {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--color-teal);
  margin-bottom: 8px;
  font-weight: 500;
}

.tech-tag-group span {
  display: inline-block;
  font-size: 12px;
  color: var(--color-text-sub);
  margin-right: 4px;
}

.tech-tag-group span:not(:last-child)::after {
  content: " / ";
  color: var(--color-teal-light);
}

/* ============================================
   AI Service Cards (service.html)
   ============================================ */
.ai-cards {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 20px;
  margin: 28px 0;
}

.ai-card {
  border: 1px solid var(--color-teal-light);
  border-top: 2px solid var(--color-teal);
  padding: 24px;
}

.ai-card h4 {
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 10px;
}

.ai-card p {
  color: var(--color-text-sub);
}

/* ============================================
   Note Box
   ============================================ */
.note-box {
  border: 1px solid var(--color-teal-light);
  padding: 16px 20px;
  font-size: 12px;
  color: var(--color-text-sub);
  margin-top: 20px;
}

/* ============================================
   CTA Banner
   ============================================ */
.cta-banner {
  background: var(--color-teal);
  color: #fff;
  padding: 48px 0;
}

.cta-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.cta-text {
  font-size: 15px;
  font-weight: 400;
}

/* ============================================
   Strength Table (about.html)
   ============================================ */
.strength-table {
  width: 100%;
  border-collapse: collapse;
  font-size: 13px;
  margin-bottom: 48px;
}

.strength-table thead th {
  background: var(--color-teal);
  color: #fff;
  font-weight: 500;
  padding: 12px 16px;
  text-align: left;
  border: 1px solid var(--color-teal);
}

.strength-table td {
  padding: 14px 16px;
  border: 1px solid var(--color-teal-light);
  vertical-align: top;
}

.strength-table td:first-child {
  background: var(--color-teal-bg);
  color: var(--color-teal);
  font-weight: 500;
  white-space: nowrap;
  width: 200px;
}

/* ============================================
   Contact Form
   ============================================ */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 340px;
  gap: 0;
  margin: 48px 0;
}

.contact-form-area {
  padding-right: 48px;
}

.contact-info-area {
  padding-left: 48px;
  border-left: 1px solid var(--color-teal);
}

.form-group {
  margin-bottom: 20px;
}

.form-group label {
  display: block;
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 6px;
}

.form-group label .required {
  font-size: 10px;
  color: #c0392b;
  margin-left: 6px;
  font-weight: 400;
}

.form-group label .optional {
  font-size: 10px;
  color: var(--color-text-sub);
  margin-left: 6px;
  font-weight: 400;
}

.form-group input,
.form-group select,
.form-group textarea {
  width: 100%;
  padding: 10px 14px;
  border: 1px solid var(--color-teal);
  font-family: "DM Sans", "Noto Sans JP", sans-serif;
  font-size: 13px;
  font-weight: 300;
  color: var(--color-text);
  background: var(--color-bg);
  outline: none;
  transition: border-color .2s, box-shadow .2s;
}

.form-group input:focus,
.form-group select:focus,
.form-group textarea:focus {
  border-color: var(--color-teal);
  box-shadow: 0 0 0 2px rgba(26, 69, 76, .1);
}

.form-group textarea {
  min-height: 120px;
  resize: vertical;
}

.btn-submit {
  display: block;
  width: 100%;
  padding: 14px;
  background: var(--color-teal);
  color: #fff;
  font-family: "DM Sans", "Noto Sans JP", sans-serif;
  font-size: 13px;
  font-weight: 400;
  border: none;
  cursor: pointer;
  transition: background .2s;
}

.btn-submit:hover {
  background: #153a40;
}

/* Contact info */
.contact-info h3 {
  font-size: 14px;
  font-weight: 500;
  margin-bottom: 16px;
}

.contact-info dl {
  margin-bottom: 20px;
}

.contact-info dt {
  font-size: 11px;
  text-transform: uppercase;
  letter-spacing: .06em;
  color: var(--color-teal);
  margin-bottom: 4px;
  font-weight: 500;
}

.contact-info dd {
  color: var(--color-text-sub);
  margin-bottom: 14px;
}

.map-placeholder {
  width: 100%;
  height: 180px;
  background: var(--color-teal-bg);
  border: 1px solid var(--color-teal-light);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 12px;
  color: var(--color-text-sub);
}

/* Form messages */
.form-message {
  padding: 14px 20px;
  margin-bottom: 20px;
  font-size: 13px;
}

.form-message.success {
  background: var(--color-teal-bg);
  border-left: 3px solid var(--color-teal);
  color: var(--color-teal);
}

.form-message.error {
  background: #fdf2f2;
  border-left: 3px solid #c0392b;
  color: #c0392b;
}

/* Honeypot */
.hp-field {
  position: absolute;
  left: -9999px;
  opacity: 0;
  height: 0;
  width: 0;
  overflow: hidden;
}

/* ============================================
   Footer
   ============================================ */
.footer {
  border-top: 1px solid var(--color-teal);
  padding: 24px 0;
}

.footer-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.footer-copy {
  font-size: 11px;
  color: var(--color-text-sub);
}

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

.footer-links a {
  font-size: 11px;
  color: var(--color-teal);
  transition: color .2s;
}

.footer-links a:hover {
  color: var(--color-text);
}

/* ============================================
   Scroll Animation
   ============================================ */
.fade-in {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity .6s ease, transform .6s ease;
}

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

/* ============================================
   Service block spacing
   ============================================ */
.service-block {
  margin-bottom: 64px;
}

.service-catch {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 16px;
  line-height: 1.8;
}

.service-lead {
  color: var(--color-text-sub);
  margin-bottom: 20px;
}

/* ============================================
   Company philosophy
   ============================================ */
.company-name-block {
  margin-bottom: 48px;
}

.company-name {
  font-size: 20px;
  font-weight: 500;
  color: var(--color-teal);
  margin-bottom: 8px;
}

.company-philosophy {
  font-size: 13px;
  font-weight: 500;
  margin-bottom: 16px;
}

.company-lead {
  color: var(--color-text-sub);
  max-width: 640px;
}

/* ============================================
   Page lead text
   ============================================ */
.page-lead {
  font-size: 13px;
  color: var(--color-text-sub);
  margin-top: 8px;
}

/* ============================================
   Responsive — Tablet (max-width: 768px)
   ============================================ */
@media (max-width: 768px) {
  .hero-heading {
    font-size: 24px;
  }

  .hero-year {
    font-size: 70px;
    right: 16px;
    bottom: 16px;
  }

  .stats-inner {
    grid-template-columns: repeat(3, 1fr);
  }

  .stat-number {
    font-size: 32px;
  }

  .services-grid {
    grid-template-columns: 1fr;
    gap: 0;
    background: var(--color-bg);
  }

  .service-card {
    border-top: 1px solid var(--color-teal);
  }

  .service-card:first-child {
    border-top-width: 2px;
  }

  .about-strip-inner {
    grid-template-columns: 1fr;
    gap: 32px;
  }

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

  .ai-cards {
    grid-template-columns: 1fr;
  }

  .contact-layout {
    grid-template-columns: 1fr;
  }

  .contact-form-area {
    padding-right: 0;
    padding-bottom: 40px;
  }

  .contact-info-area {
    padding-left: 0;
    padding-top: 40px;
    border-left: none;
    border-top: 1px solid var(--color-teal);
  }

  .cta-inner {
    flex-direction: column;
    text-align: center;
  }

  .nav-links {
    display: none;
    position: absolute;
    top: 56px;
    left: 0;
    right: 0;
    background: var(--color-bg);
    flex-direction: column;
    padding: 16px 24px;
    gap: 16px;
    border-bottom: 1px solid var(--color-teal);
  }

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

  .nav-hamburger {
    display: flex;
  }

  .footer-inner {
    flex-direction: column;
    gap: 12px;
    text-align: center;
  }

  .strength-table td:first-child {
    width: auto;
    white-space: normal;
  }
}

/* ============================================
   Responsive — Mobile (max-width: 480px)
   ============================================ */
@media (max-width: 480px) {
  .container {
    padding: 0 16px;
  }

  .hero {
    padding: 48px 0 40px;
  }

  .hero-heading {
    font-size: 20px;
  }

  .hero-year {
    font-size: 50px;
  }

  .hero-cta {
    flex-direction: column;
    align-items: flex-start;
    gap: 12px;
  }

  .stat-number {
    font-size: 28px;
  }

  .stat-label {
    font-size: 10px;
  }

  .section {
    padding: 40px 0;
  }

  .page-title {
    font-size: 22px;
  }

  .tech-tags {
    grid-template-columns: 1fr;
  }
}