/* =========================================================
   Bis Tree Inc. Website
   Shared stylesheet for English and Japanese pages
   ========================================================= */

:root {
  --bg: #0b1020;
  --bg-deep: #071024;
  --card: rgba(255, 255, 255, 0.065);
  --card-strong: rgba(14, 23, 45, 0.72);
  --text: #eef3ff;
  --muted: #b7c2e0;
  --line: rgba(255, 255, 255, 0.14);
  --accent: #73e0a9;
  --accent-2: #79b8ff;
  --warn: #ffd166;
  --shadow: 0 24px 60px rgba(0, 0, 0, 0.35);
  --radius: 22px;
  --max: 1180px;
}

* {
  box-sizing: border-box;
}

html {
  scroll-behavior: smooth;
}

body {
  margin: 0;
  font-family:
    Inter,
    ui-sans-serif,
    system-ui,
    -apple-system,
    BlinkMacSystemFont,
    "Segoe UI",
    sans-serif;
  background:
    radial-gradient(circle at top left, rgba(121, 184, 255, 0.16), transparent 28%),
    radial-gradient(circle at top right, rgba(115, 224, 169, 0.10), transparent 24%),
    linear-gradient(180deg, #0a1022 0%, #0b1020 100%);
  color: var(--text);
  line-height: 1.6;
}

body.ja {
  font-family:
    "Noto Sans JP",
    "Hiragino Sans",
    "Yu Gothic",
    Inter,
    system-ui,
    sans-serif;
  line-height: 1.75;
}

img {
  max-width: 100%;
}

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

.container {
  width: min(var(--max), calc(100% - 32px));
  margin: 0 auto;
}

/* Navigation */

.nav {
  position: sticky;
  top: 0;
  z-index: 30;
  backdrop-filter: blur(16px);
  background: rgba(11, 16, 32, 0.82);
  border-bottom: 1px solid var(--line);
}

.nav-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 22px;
  padding: 14px 0;
}

.brand {
  display: flex;
  align-items: center;
  gap: 14px;
  min-width: 0;
}

.brand-logo {
  display: block;
  width: auto;
  height: 54px;
  object-fit: contain;
  flex: 0 0 auto;
}

.brand-text {
  color: #ffffff;
  font-size: 1.35rem;
  font-weight: 800;
  letter-spacing: -0.02em;
  white-space: nowrap;
}

body.ja .brand-text {
  font-size: 1.16rem;
  letter-spacing: 0.02em;
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 18px;
  flex-wrap: wrap;
  color: var(--muted);
  font-size: 0.94rem;
}

.nav-links a {
  transition: color 0.2s ease;
}

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

.language-link {
  padding: 8px 11px;
  border: 1px solid var(--line);
  border-radius: 999px;
  color: var(--text);
}

/* Hero */

.hero {
  padding: 42px 0 34px;
}

.hero-shell {
  position: relative;
  overflow: hidden;
  min-height: 560px;
  display: grid;
  grid-template-columns: minmax(0, 1.34fr) minmax(300px, 0.66fr);
  gap: 26px;
  align-items: stretch;
  padding: 28px;
  border: 1px solid var(--line);
  border-radius: 26px;
  background:
    linear-gradient(90deg, rgba(8, 14, 30, 0.91) 0%, rgba(8, 14, 30, 0.69) 45%, rgba(8, 14, 30, 0.43) 100%),
    url("assets/hero-tokyo-skyline.jpg") center center / cover no-repeat;
  box-shadow: var(--shadow);
}

.hero-main,
.hero-side {
  position: relative;
  z-index: 1;
}

.hero-main {
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  min-width: 0;
}

.hero-copy {
  max-width: 760px;
}

.eyebrow {
  display: inline-flex;
  align-items: center;
  max-width: 100%;
  gap: 10px;
  padding: 8px 13px;
  margin-bottom: 18px;
  border: 1px solid rgba(121, 184, 255, 0.30);
  border-radius: 999px;
  background: rgba(121, 184, 255, 0.10);
  color: #d9e8ff;
  font-size: 0.9rem;
  line-height: 1.2;
}

h1,
h2,
h3,
p {
  margin-top: 0;
}

h1 {
  max-width: 760px;
  margin-bottom: 18px;
  font-size: clamp(2.45rem, 4.6vw, 4.35rem);
  line-height: 1.08;
  letter-spacing: -0.045em;
}

body.ja h1 {
  max-width: 780px;
  font-size: clamp(2.25rem, 4.2vw, 4rem);
  line-height: 1.18;
  letter-spacing: -0.035em;
}

.lead {
  max-width: 66ch;
  margin-bottom: 26px;
  color: #d7e3ff;
  font-size: 1.04rem;
}

body.ja .lead {
  max-width: 70ch;
  font-size: 1.02rem;
}

.hero-actions {
  display: flex;
  gap: 14px;
  flex-wrap: wrap;
  margin-bottom: 24px;
}

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  min-height: 46px;
  padding: 13px 18px;
  border: 1px solid var(--line);
  border-radius: 14px;
  font-size: 0.92rem;
  font-weight: 700;
  transition: 0.2s ease;
}

.btn:hover {
  transform: translateY(-1px);
}

.btn-primary {
  border: none;
  background: linear-gradient(135deg, var(--accent), var(--accent-2));
  color: #0b1020;
}

.btn-secondary {
  background: rgba(255, 255, 255, 0.045);
  color: var(--text);
}

.hero-mini-grid {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 14px;
  margin-top: 22px;
}

.hero-mini {
  min-height: 125px;
  padding: 17px;
  border: 1px solid var(--line);
  border-radius: 17px;
  background: rgba(17, 26, 50, 0.62);
  backdrop-filter: blur(8px);
}

.hero-mini strong {
  display: block;
  margin-bottom: 8px;
  font-size: 0.96rem;
  line-height: 1.35;
}

.hero-mini span {
  color: #d3ddf7;
  font-size: 0.9rem;
  line-height: 1.55;
}

.hero-side {
  display: grid;
  grid-template-rows: repeat(3, 1fr);
  gap: 16px;
}

.hero-info {
  padding: 20px;
  border: 1px solid rgba(255, 255, 255, 0.16);
  border-radius: 18px;
  background: rgba(14, 24, 50, 0.52);
  backdrop-filter: blur(9px);
}

.hero-info-label {
  margin-bottom: 10px;
  color: #9fbcff;
  font-size: 0.76rem;
  font-weight: 700;
  letter-spacing: 0.08em;
  text-transform: uppercase;
}

.hero-info h3 {
  margin-bottom: 8px;
  font-size: 1.02rem;
  line-height: 1.35;
}

.hero-info p {
  margin-bottom: 0;
  color: #d7e3ff;
  font-size: 0.88rem;
  line-height: 1.62;
}

/* Sections */

section {
  padding: 34px 0;
}

.section-head {
  max-width: 760px;
  margin-bottom: 20px;
}

.section-head h2 {
  margin-bottom: 8px;
  font-size: clamp(1.65rem, 2.5vw, 2.3rem);
  line-height: 1.18;
  letter-spacing: -0.03em;
}

.section-head p {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 1rem;
}

.grid-3,
.grid-2,
.process-grid {
  display: grid;
  gap: 18px;
}

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

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

.card,
.step {
  padding: 24px;
  border: 1px solid var(--line);
  border-radius: var(--radius);
  background: var(--card);
  box-shadow: var(--shadow);
}

.card h3,
.step h3 {
  margin-bottom: 12px;
  font-size: 1.12rem;
  line-height: 1.35;
}

.card p,
.card li,
.step p {
  color: var(--muted);
}

.card p:last-child,
.step p:last-child {
  margin-bottom: 0;
}

.card-image {
  width: 100%;
  height: 158px;
  margin-bottom: 18px;
  object-fit: cover;
  border-radius: 16px;
  border: 1px solid var(--line);
}

ul {
  padding-left: 18px;
  margin: 12px 0 0;
}

li + li {
  margin-top: 6px;
}

/* Visual sections */

.tech-visual,
.process-visual {
  margin-bottom: 18px;
  overflow: hidden;
  border: 1px solid var(--line);
  border-radius: 20px;
  background: rgba(255, 255, 255, 0.035);
}

.tech-visual img,
.process-visual img {
  display: block;
  width: 100%;
  height: auto;
  object-fit: contain;
}

.process-grid {
  grid-template-columns: repeat(4, 1fr);
}

.step-num {
  width: 34px;
  height: 34px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 14px;
  border-radius: 999px;
  background: rgba(115, 224, 169, 0.18);
  color: var(--accent);
  font-weight: 800;
}

/* Disclaimer and footer */

.disclaimer-banner {
  padding: 20px;
  border: 1px solid rgba(255, 209, 102, 0.35);
  border-radius: 18px;
  background: rgba(255, 209, 102, 0.08);
  color: #fff5d6;
}

.disclaimer-banner strong {
  display: block;
  margin-bottom: 8px;
  color: var(--warn);
}

.footer {
  padding: 36px 0 56px;
  color: var(--muted);
}

.footer-box {
  display: grid;
  grid-template-columns: 260px 1fr;
  gap: 30px;
  align-items: stretch;
  padding: 26px;
  border: 1px solid var(--line);
  border-radius: 22px;
  background: rgba(255, 255, 255, 0.045);
}

.footer-logo {
  min-height: 220px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: #0b1020;
  border: 1px solid var(--line);
  border-radius: 18px;
  overflow: hidden;
}

.footer-logo img {
  width: 100%;
  height: 100%;
  object-fit: contain;
}

.footer-content h2 {
  margin-bottom: 10px;
  color: var(--text);
}

.footer small {
  display: block;
  margin-top: 14px;
  color: #9ba8cc;
  line-height: 1.6;
}

/* Responsive */

@media (max-width: 1040px) {
  .hero-shell {
    grid-template-columns: 1fr;
    min-height: auto;
  }

  .hero-side {
    grid-template-columns: 1fr;
    grid-template-rows: auto;
  }

  .grid-3,
  .grid-2,
  .process-grid {
    grid-template-columns: 1fr;
  }

  .hero-mini-grid {
    grid-template-columns: 1fr;
  }

  .footer-box {
    grid-template-columns: 1fr;
  }

  .footer-logo {
    justify-content: flex-start;
  }

  .footer-logo img {
    width: auto;
    height: 180px;
  }
}

@media (max-width: 720px) {
  .nav-inner {
    align-items: flex-start;
    flex-direction: column;
  }

  .brand-logo {
    height: 46px;
  }

  .brand-text {
    font-size: 1.15rem;
  }

  body.ja .brand-text {
    font-size: 1rem;
  }

  .hero {
    padding-top: 24px;
  }

  .hero-shell {
    padding: 20px;
    border-radius: 20px;
  }

  h1,
  body.ja h1 {
    font-size: clamp(2.05rem, 10vw, 3.1rem);
  }

  .card,
  .step {
    padding: 20px;
  }

  .card-image {
    height: 180px;
  }
}

/* Contact form */

.contact-toggle {
  margin: 8px 0 18px;
}

.contact-form {
  display: grid;
  gap: 14px;
  max-width: 640px;
  margin: 18px 0 20px;
  padding: 18px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(14, 23, 45, 0.56);
}

.contact-form[hidden] {
  display: none;
}

.form-field {
  display: grid;
  gap: 7px;
}

.form-field label {
  color: var(--text);
  font-size: 0.92rem;
  font-weight: 700;
}

.form-field input,
.form-field textarea {
  width: 100%;
  padding: 12px 13px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.075);
  color: var(--text);
  font: inherit;
  outline: none;
}

.form-field input:focus,
.form-field textarea:focus {
  border-color: rgba(121, 184, 255, 0.65);
  box-shadow: 0 0 0 3px rgba(121, 184, 255, 0.12);
}

.form-field textarea {
  resize: vertical;
  min-height: 130px;
}

.form-note {
  margin-bottom: 0;
  color: var(--muted);
  font-size: 0.9rem;
}

.form-message {
  max-width: 640px;
  margin: 12px 0 18px;
  padding: 12px 14px;
  border-radius: 12px;
  font-size: 0.94rem;
}

.form-message.success {
  border: 1px solid rgba(115, 224, 169, 0.45);
  background: rgba(115, 224, 169, 0.12);
  color: #dfffe9;
}

.form-message.error {
  border: 1px solid rgba(255, 209, 102, 0.45);
  background: rgba(255, 209, 102, 0.10);
  color: #fff5d6;
}

.form-honeypot {
  position: absolute !important;
  left: -9999px !important;
  opacity: 0 !important;
}


/* Contact form production hardening */
.footer-content {
  min-width: 0;
}

.contact-form {
  display: grid;
  grid-template-columns: 1fr;
  gap: 14px;
  width: min(100%, 640px);
  margin: 18px 0 20px;
  padding: 20px;
  border: 1px solid var(--line);
  border-radius: 18px;
  background: rgba(14, 23, 45, 0.72);
}

.contact-form[hidden] {
  display: none !important;
}

.form-field {
  display: grid;
  grid-template-columns: 1fr;
  gap: 7px;
}

.form-field label {
  display: block;
  color: var(--text);
  font-size: 0.92rem;
  font-weight: 700;
}

.form-field input,
.form-field textarea {
  display: block;
  width: 100%;
  min-width: 0;
  padding: 12px 13px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: rgba(255, 255, 255, 0.08);
  color: var(--text);
  font: inherit;
  outline: none;
}

.form-field input:focus,
.form-field textarea:focus {
  border-color: rgba(121, 184, 255, 0.65);
  box-shadow: 0 0 0 3px rgba(121, 184, 255, 0.12);
}

.form-field textarea {
  resize: vertical;
  min-height: 130px;
}

.form-note {
  margin: 0;
  color: var(--muted);
  font-size: 0.9rem;
}