/* ========================================
   Simpson Biomedical — Herbal Premium Style
   Palette: Sage Green + Warm Bronze + Natural Cream
   ======================================== */

:root {
  /* Brand Colors — Herbal & Trustworthy */
  --green: #3d6b4f;
  --green-deep: #2a4e38;
  --green-light: #5a8f6e;
  --green-muted: #8bab93;
  --green-pale: #d4e4d8;

  --bronze: #a6875a;
  --bronze-light: #c4a876;
  --bronze-dark: #8a6d42;

  --cream: #faf8f4;
  --cream-warm: #f5f1ea;
  --cream-dark: #ece6db;
  --ivory: #fffdf9;

  /* Neutrals */
  --white: #ffffff;
  --text-dark: #2c3529;
  --text-body: #5a6356;
  --text-light: #8a9185;
  --text-muted: #b0b7ab;
  --border: #e2ddd4;
  --border-light: #eeebe5;

  /* Typography */
  --font-display: 'Cormorant Garamond', 'Georgia', serif;
  --font-body: 'Noto Sans TC', 'Inter', -apple-system, sans-serif;
  --font-en: 'Inter', 'Noto Sans TC', sans-serif;

  /* Spacing */
  --section-padding: 130px;

  /* Effects */
  --shadow-soft: 0 2px 16px rgba(44, 53, 41, 0.04);
  --shadow-medium: 0 8px 32px rgba(44, 53, 41, 0.06);
  --shadow-elevated: 0 16px 48px rgba(44, 53, 41, 0.08);
  --radius: 14px;
  --radius-sm: 8px;
  --transition: 0.4s cubic-bezier(0.25, 0.46, 0.45, 0.94);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 100px;
  font-size: 16px;
}

body {
  font-family: var(--font-body);
  font-size: 1rem;
  line-height: 1.8;
  color: var(--text-body);
  background: var(--ivory);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

::selection {
  background: var(--green-muted);
  color: var(--white);
}

a {
  color: inherit;
  text-decoration: none;
  transition: color var(--transition);
}

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

.container {
  max-width: 1240px;
  margin: 0 auto;
  padding: 0 40px;
}

/* ========================================
   Navigation
   ======================================== */
.navbar {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 1000;
  background: transparent;
  transition: all 0.5s ease;
}

.navbar.scrolled {
  background: rgba(255, 253, 249, 0.95);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  box-shadow: 0 1px 0 var(--border-light);
}

.nav-container {
  display: flex;
  align-items: center;
  height: 84px;
}

/* Logo */
.logo {
  display: flex;
  align-items: center;
  gap: 14px;
}

.logo-mark {
  width: 40px; height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--green);
  color: var(--white);
  font-family: var(--font-display);
  font-size: 1.2rem;
  font-weight: 600;
  border-radius: 8px;
}

.logo-group {
  display: flex;
  flex-direction: column;
  line-height: 1;
}

.logo-text {
  font-family: var(--font-en);
  font-size: 0.9rem;
  font-weight: 600;
  letter-spacing: 3px;
  color: var(--text-dark);
  transition: color var(--transition);
}

.logo-sub {
  font-family: var(--font-en);
  font-size: 0.58rem;
  font-weight: 400;
  letter-spacing: 4px;
  color: var(--text-muted);
  margin-top: 3px;
}

/* Hero state: logo light on dark image */
.navbar:not(.scrolled) .logo-text { color: var(--white); }
.navbar:not(.scrolled) .logo-sub { color: rgba(255,255,255,0.5); }
.navbar:not(.scrolled) .logo-mark { background: rgba(255,255,255,0.15); backdrop-filter: blur(8px); }
.navbar:not(.scrolled) .nav-toggle span { background: var(--white); }

/* Nav Links */
.nav-links {
  display: flex;
  list-style: none;
  gap: 4px;
  align-items: center;
  margin-left: auto;
}

/* Language Switch */
.lang-switch {
  display: flex;
  align-items: center;
  gap: 2px;
  margin-left: 18px;
}

.lang-btn {
  background: none;
  border: none;
  padding: 6px 8px;
  font-size: 0.72rem;
  font-weight: 500;
  letter-spacing: 1px;
  cursor: pointer;
  color: var(--text-muted);
  border-radius: 4px;
  transition: all var(--transition);
  font-family: var(--font-en);
}

.lang-btn.active {
  color: var(--green);
  font-weight: 600;
}

.lang-btn:hover { color: var(--green-light); }

.lang-sep {
  font-size: 0.65rem;
  color: var(--text-muted);
  opacity: 0.3;
  user-select: none;
}

/* Hero state — lang switch */
.navbar:not(.scrolled) .lang-btn { color: rgba(255,255,255,0.4); }
.navbar:not(.scrolled) .lang-btn.active { color: var(--white); }
.navbar:not(.scrolled) .lang-btn:hover { color: rgba(255,255,255,0.8); }
.navbar:not(.scrolled) .lang-sep { color: rgba(255,255,255,0.2); }

.nav-links a {
  display: block;
  padding: 10px 20px;
  font-size: 0.84rem;
  font-weight: 400;
  letter-spacing: 1px;
  color: var(--text-light);
  border-radius: 8px;
  transition: all var(--transition);
}

.nav-links a:hover {
  color: var(--green);
  background: rgba(61, 107, 79, 0.04);
}

.nav-cta {
  background: var(--green) !important;
  color: var(--white) !important;
  font-weight: 500 !important;
}

.nav-cta:hover {
  background: var(--green-deep) !important;
  color: var(--white) !important;
}

/* Nav hero state — white text on dark image */
.navbar:not(.scrolled) .nav-links a {
  color: rgba(255,255,255,0.7);
}
.navbar:not(.scrolled) .nav-links a:hover {
  color: var(--white);
  background: rgba(255,255,255,0.08);
}
.navbar:not(.scrolled) .nav-cta {
  background: rgba(255,255,255,0.12) !important;
  color: var(--white) !important;
  border: 1px solid rgba(255,255,255,0.2);
}
.navbar:not(.scrolled) .nav-cta:hover {
  background: rgba(255,255,255,0.2) !important;
}

/* Nav Toggle */
.nav-toggle {
  display: none;
  flex-direction: column;
  gap: 6px;
  background: none;
  border: none;
  cursor: pointer;
  padding: 8px;
}

.nav-toggle span {
  display: block;
  width: 26px;
  height: 1.5px;
  background: var(--text-dark);
  border-radius: 2px;
  transition: all var(--transition);
}

/* ========================================
   Hero Section — Full Background Image
   ======================================== */
.hero {
  position: relative;
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  background: var(--green-deep);
}

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

.hero-bg-img {
  width: 100%;
  height: 100%;
  object-fit: cover;
  object-position: center;
  display: block;
}

.hero-overlay {
  position: absolute;
  inset: 0;
  background:
    linear-gradient(180deg,
      rgba(42, 78, 56, 0.55) 0%,
      rgba(42, 78, 56, 0.40) 40%,
      rgba(42, 78, 56, 0.60) 100%
    );
  backdrop-filter: blur(1px);
}

.hero-content {
  position: relative;
  z-index: 2;
  text-align: center;
  padding: 120px 0 80px;
}

.hero-eyebrow {
  font-family: var(--font-en);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 4px;
  text-transform: uppercase;
  color: var(--bronze-light);
  margin-bottom: 40px;
  opacity: 0;
  animation: fadeUp 1s ease 0.3s forwards;
}

.hero-title {
  margin-bottom: 32px;
  opacity: 0;
  animation: fadeUp 1s ease 0.5s forwards;
}

.hero-title-zh {
  display: block;
  font-size: clamp(2.4rem, 5.5vw, 4rem);
  font-weight: 700;
  color: var(--white);
  letter-spacing: 8px;
  margin-bottom: 12px;
  text-shadow: 0 2px 20px rgba(0,0,0,0.15);
}

.hero-title-en {
  display: block;
  font-family: var(--font-display);
  font-size: clamp(1.3rem, 2.8vw, 2.2rem);
  font-weight: 400;
  color: rgba(255,255,255,0.5);
  letter-spacing: 5px;
  font-style: italic;
}

.hero-line {
  width: 50px;
  height: 1px;
  background: rgba(255,255,255,0.4);
  margin: 0 auto 32px;
  opacity: 0;
  animation: fadeUp 1s ease 0.7s forwards;
}

.hero-subtitle {
  font-size: 1.05rem;
  font-weight: 300;
  color: rgba(255,255,255,0.85);
  letter-spacing: 3px;
  margin-bottom: 14px;
  opacity: 0;
  animation: fadeUp 1s ease 0.8s forwards;
}

.hero-desc {
  font-size: 0.92rem;
  color: rgba(255,255,255,0.55);
  margin-bottom: 48px;
  line-height: 2;
  opacity: 0;
  animation: fadeUp 1s ease 0.9s forwards;
}

.hero-actions {
  display: flex;
  gap: 16px;
  justify-content: center;
  flex-wrap: wrap;
  opacity: 0;
  animation: fadeUp 1s ease 1s forwards;
}

/* Scroll indicator — minimal line */
.hero-scroll {
  position: relative;
  z-index: 2;
  display: flex;
  justify-content: center;
  margin-top: 56px;
  opacity: 0;
  animation: fadeUp 1s ease 1.2s forwards;
  cursor: pointer;
}

.hero-scroll-line {
  width: 1px;
  height: 48px;
  background: linear-gradient(to bottom, rgba(255,255,255,0.35), transparent);
  animation: linePulse 2.5s ease-in-out infinite;
}

.hero-scroll:hover .hero-scroll-line {
  background: linear-gradient(to bottom, rgba(255,255,255,0.6), transparent);
}

@keyframes linePulse {
  0% { opacity: 0.4; transform: scaleY(0.6); transform-origin: top; }
  50% { opacity: 1; transform: scaleY(1); transform-origin: top; }
  100% { opacity: 0.4; transform: scaleY(0.6); transform-origin: top; }
}

@keyframes fadeUp {
  from { opacity: 0; transform: translateY(24px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ========================================
   Buttons
   ======================================== */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 10px;
  padding: 15px 38px;
  font-family: var(--font-body);
  font-size: 0.86rem;
  font-weight: 500;
  letter-spacing: 2px;
  border: 1px solid transparent;
  border-radius: 4px;
  cursor: pointer;
  transition: all var(--transition);
}

.btn-gold {
  background: var(--green);
  color: var(--white);
  border-color: var(--green);
}

.btn-gold:hover {
  background: var(--green-deep);
  border-color: var(--green-deep);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(61, 107, 79, 0.2);
}

.btn-ghost {
  background: transparent;
  color: rgba(255,255,255,0.8);
  border-color: rgba(255,255,255,0.3);
}

.btn-ghost:hover {
  color: var(--white);
  border-color: rgba(255,255,255,0.6);
  background: rgba(255,255,255,0.08);
}

.btn-dark {
  background: var(--green);
  color: var(--white);
  border-color: var(--green);
}

.btn-dark:hover {
  background: var(--green-deep);
  transform: translateY(-2px);
  box-shadow: 0 8px 28px rgba(61, 107, 79, 0.18);
  color: var(--white);
}

.btn-full { width: 100%; justify-content: center; }

/* ========================================
   Section Shared
   ======================================== */
.section {
  padding: var(--section-padding) 0;
  position: relative;
}

.section-cream { background: var(--cream-warm); }

.section-dark {
  background: var(--green-deep);
  position: relative;
  overflow: hidden;
}

.section-dark-bg {
  position: absolute;
  inset: 0;
  opacity: 0.04;
  background-image:
    radial-gradient(circle at 20% 50%, var(--white) 1px, transparent 1px),
    radial-gradient(circle at 80% 50%, var(--white) 1px, transparent 1px);
  background-size: 80px 80px;
}

.section-header {
  margin-bottom: 72px;
}

.section-number {
  display: block;
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--bronze);
  letter-spacing: 2px;
  margin-bottom: 10px;
  font-style: italic;
}

.section-en {
  font-family: var(--font-en);
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 4px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 10px;
}

.section-title {
  font-size: clamp(1.8rem, 3.5vw, 2.5rem);
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: 3px;
  line-height: 1.3;
}

.section-header--light .section-en { color: rgba(255,255,255,0.35); }
.section-header--light .section-title { color: var(--white); }

/* ========================================
   About Section
   ======================================== */
.about-layout {
  display: grid;
  grid-template-columns: 1fr 380px;
  gap: 80px;
  align-items: start;
}

.about-lead {
  margin-bottom: 36px;
  padding-bottom: 36px;
  border-bottom: 1px solid var(--border-light);
}

.about-lead p {
  font-size: 1.25rem;
  font-weight: 300;
  line-height: 2.1;
  color: var(--text-dark);
  letter-spacing: 1px;
}

.about-body p {
  margin-bottom: 22px;
  font-size: 0.95rem;
  line-height: 2;
  color: var(--text-light);
}

.about-body strong {
  color: var(--green);
  font-weight: 600;
}

/* Cert Cards */
.about-certs {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.cert-card {
  display: flex;
  align-items: center;
  gap: 18px;
  padding: 26px 24px;
  background: var(--cream);
  border-radius: var(--radius-sm);
  border: 1px solid var(--border-light);
  transition: all var(--transition);
}

.cert-card:hover {
  background: var(--white);
  border-color: var(--green-pale);
  box-shadow: var(--shadow-medium);
  transform: translateX(4px);
}

.cert-badge {
  flex-shrink: 0;
  width: 48px; height: 48px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--green);
}

.cert-badge svg { width: 34px; height: 34px; }

.cert-card h4 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: 1px;
  margin-bottom: 2px;
}

.cert-card p {
  font-size: 0.76rem;
  color: var(--text-muted);
  line-height: 1.5;
}

/* ========================================
   Philosophy Section
   ======================================== */
.philosophy-grid {
  display: grid;
  grid-template-columns: repeat(4, 1fr);
  gap: 1px;
  background: rgba(255,255,255,0.08);
  position: relative;
  z-index: 1;
}

.philosophy-card {
  padding: 48px 32px;
  background: var(--green-deep);
  transition: all var(--transition);
}

.philosophy-card:hover {
  background: rgba(255,255,255,0.04);
}

.philosophy-num {
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--bronze-light);
  font-style: italic;
  margin-bottom: 18px;
}

.philosophy-line {
  width: 28px;
  height: 1px;
  background: var(--bronze-light);
  opacity: 0.3;
  margin-bottom: 22px;
  transition: all var(--transition);
}

.philosophy-card:hover .philosophy-line {
  width: 48px;
  opacity: 0.7;
}

.philosophy-card h3 {
  font-size: 1.1rem;
  font-weight: 700;
  color: var(--white);
  letter-spacing: 2px;
  margin-bottom: 14px;
}

.philosophy-card p {
  font-size: 0.84rem;
  line-height: 1.9;
  color: rgba(255,255,255,0.42);
}

/* ========================================
   Services Section — Style G: Side Index + Cards
   ======================================== */
.services-index-layout {
  display: grid;
  grid-template-columns: 200px 1fr;
  gap: 64px;
}

.services-side-index {
  position: sticky;
  top: 100px;
  align-self: start;
}

.services-idx-label {
  font-family: var(--font-en);
  font-size: 0.6rem;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 20px;
}

.services-idx-item {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 10px 0;
  cursor: pointer;
  transition: all var(--transition);
  border-left: 2px solid transparent;
  padding-left: 16px;
  margin-left: -16px;
  color: var(--text-light);
}

.services-idx-item:hover { color: var(--green); }

.services-idx-item.active {
  border-left-color: var(--green);
  color: var(--green);
}

.services-idx-num {
  font-family: var(--font-display);
  font-size: 0.85rem;
  color: var(--bronze);
  min-width: 24px;
}

.services-idx-text {
  font-size: 0.82rem;
  letter-spacing: 1px;
}

.services-cards {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.services-card {
  display: grid;
  grid-template-columns: 72px 1fr;
  gap: 32px;
  padding: 40px;
  background: var(--white);
  border: 1px solid var(--border-light);
  border-radius: 4px;
  transition: all var(--transition);
  scroll-margin-top: 100px;
}

.services-card:hover {
  border-color: var(--green-pale);
  box-shadow: 0 8px 32px rgba(61,107,79,0.06);
}

.services-card-num {
  font-family: var(--font-display);
  font-size: 2.8rem;
  font-weight: 300;
  color: var(--green-pale);
  line-height: 1;
  transition: color var(--transition);
}

.services-card:hover .services-card-num { color: var(--green-muted); }

.services-card-en {
  font-family: var(--font-en);
  font-size: 0.62rem;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 6px;
}

html[lang="en"] .services-card-en { display: none; }

.services-card-title {
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--text-dark);
  letter-spacing: 2px;
  margin-bottom: 12px;
}

.services-card-line {
  width: 28px;
  height: 1px;
  background: var(--bronze);
  margin-bottom: 14px;
}

.services-card-desc {
  font-size: 0.85rem;
  color: var(--text-light);
  line-height: 1.8;
}

/* ========================================
   Features Section
   ======================================== */
.features-grid {
  display: grid;
  grid-template-columns: repeat(5, 1fr);
  gap: 0;
  border: 1px solid var(--border);
  border-radius: var(--radius);
  overflow: hidden;
}

.feature-card {
  padding: 40px 28px;
  background: var(--white);
  border-right: 1px solid var(--border);
  transition: all var(--transition);
  display: flex;
  flex-direction: column;
}

.feature-card:last-child { border-right: none; }

.feature-card:hover {
  background: var(--green-deep);
}

.feature-card:hover .feature-num { color: var(--bronze-light); }
.feature-card:hover h3 { color: var(--white); }
.feature-card:hover p { color: rgba(255,255,255,0.5); }
.feature-card:hover .feature-arrow { color: var(--bronze-light); opacity: 1; }

.feature-num {
  font-family: var(--font-display);
  font-size: 1.8rem;
  font-weight: 400;
  color: var(--border);
  margin-bottom: 22px;
  font-style: italic;
  transition: color var(--transition);
}

.feature-card h3 {
  font-size: 0.95rem;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: 1px;
  margin-bottom: 12px;
  transition: color var(--transition);
}

.feature-card p {
  font-size: 0.8rem;
  line-height: 1.8;
  color: var(--text-muted);
  flex: 1;
  transition: color var(--transition);
}

.feature-arrow {
  margin-top: 22px;
  color: var(--border);
  opacity: 0.5;
  transition: all var(--transition);
}

.feature-arrow svg { width: 18px; height: 18px; }

/* ========================================
   Contact Section
   ======================================== */
.contact-layout {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 80px;
  align-items: start;
}

.contact-info h3 {
  font-size: 1.5rem;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: 2px;
  margin-bottom: 14px;
}

.contact-lead {
  font-size: 0.92rem;
  line-height: 2;
  color: var(--text-muted);
  margin-bottom: 44px;
}

.contact-details {
  display: flex;
  flex-direction: column;
  gap: 24px;
}

.contact-item {
  display: flex;
  align-items: flex-start;
  gap: 16px;
}

.contact-item-icon {
  flex-shrink: 0;
  width: 42px; height: 42px;
  display: flex;
  align-items: center;
  justify-content: center;
  color: var(--green);
  background: var(--green-pale);
  border-radius: 10px;
}

.contact-item-icon svg { width: 18px; height: 18px; }

.contact-item-label {
  display: block;
  font-size: 0.7rem;
  font-weight: 500;
  letter-spacing: 2px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 3px;
}

.contact-item-value {
  font-size: 0.95rem;
  font-weight: 500;
  color: var(--text-dark);
}

a.contact-item-value:hover { color: var(--green); }

/* Contact Form */
.contact-form-card {
  background: var(--cream);
  border: 1px solid var(--border-light);
  border-radius: var(--radius);
  padding: 44px;
}

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

.form-header h4 {
  font-size: 1.05rem;
  font-weight: 700;
  color: var(--text-dark);
  letter-spacing: 1px;
  margin-bottom: 4px;
}

.form-header p {
  font-size: 0.82rem;
  color: var(--text-muted);
}

.form-row {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 14px;
}

.form-group { margin-bottom: 18px; }

.form-group label {
  display: block;
  font-size: 0.76rem;
  font-weight: 600;
  letter-spacing: 1px;
  color: var(--text-body);
  margin-bottom: 7px;
}

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

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 13px 16px;
  font-size: 0.88rem;
  font-family: var(--font-body);
  color: var(--text-dark);
  background: var(--white);
  border: 1px solid var(--border);
  border-radius: var(--radius-sm);
  outline: none;
  transition: all var(--transition);
}

.form-group input:focus,
.form-group textarea:focus {
  border-color: var(--green-muted);
  box-shadow: 0 0 0 3px rgba(61, 107, 79, 0.08);
}

.form-group input::placeholder,
.form-group textarea::placeholder {
  color: var(--text-muted);
  font-size: 0.84rem;
}

.form-group textarea {
  resize: vertical;
  min-height: 105px;
}

/* ========================================
   Footer
   ======================================== */
.footer {
  background: var(--text-dark);
  color: rgba(255,255,255,0.45);
  padding-top: 72px;
}

.footer-top {
  display: grid;
  grid-template-columns: 1.5fr 1fr 1fr 1fr;
  gap: 56px;
  padding-bottom: 56px;
  border-bottom: 1px solid rgba(255,255,255,0.06);
}

.footer-brand .logo { margin-bottom: 18px; }

.footer .logo-text { color: var(--white); }
.footer .logo-sub { color: rgba(255,255,255,0.3); }
.footer .logo-mark {
  background: rgba(61, 107, 79, 0.4);
  color: var(--green-pale);
}

.footer-desc {
  font-size: 0.82rem;
  line-height: 1.9;
  color: rgba(255,255,255,0.3);
}

.footer-nav h5 {
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 3px;
  text-transform: uppercase;
  color: rgba(255,255,255,0.5);
  margin-bottom: 22px;
}

.footer-nav a {
  display: block;
  font-size: 0.82rem;
  color: rgba(255,255,255,0.3);
  padding: 5px 0;
  transition: all var(--transition);
}

.footer-nav a:hover {
  color: var(--green-pale);
  padding-left: 4px;
}

.footer-bottom {
  display: flex;
  justify-content: space-between;
  padding: 24px 0;
}

.footer-bottom p {
  font-size: 0.72rem;
  color: rgba(255,255,255,0.15);
  letter-spacing: 1px;
}

/* ========================================
   Toast Notification
   ======================================== */
.site-toast {
  position: fixed;
  top: 100px;
  left: 50%;
  transform: translateX(-50%) translateY(-20px);
  padding: 14px 32px;
  border-radius: var(--radius-sm);
  font-size: 0.88rem;
  font-weight: 500;
  letter-spacing: 0.5px;
  opacity: 0;
  pointer-events: none;
  z-index: 9000;
  transition: opacity 0.4s ease, transform 0.4s ease;
  box-shadow: var(--shadow-elevated);
}

.site-toast.show {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

.site-toast--success {
  background: var(--green-deep);
  color: var(--white);
}

.site-toast--error {
  background: #c0392b;
  color: var(--white);
}

/* ========================================
   Scroll Animations
   ======================================== */
.reveal {
  opacity: 0;
  transform: translateY(36px);
  transition: opacity 0.8s ease, transform 0.8s ease;
}

.reveal.visible {
  opacity: 1;
  transform: translateY(0);
}

.reveal-delay-1 { transition-delay: 0.1s; }
.reveal-delay-2 { transition-delay: 0.2s; }
.reveal-delay-3 { transition-delay: 0.3s; }
.reveal-delay-4 { transition-delay: 0.4s; }

/* ========================================
   Responsive Design
   ======================================== */
@media (max-width: 1100px) {
  :root { --section-padding: 100px; }

  .features-grid { grid-template-columns: repeat(3, 1fr); }
  .feature-card:nth-child(4),
  .feature-card:nth-child(5) { border-top: 1px solid var(--border); }
  .feature-card:nth-child(3) { border-right: none; }

  .footer-top { grid-template-columns: 1fr 1fr; gap: 40px; }
}

@media (max-width: 900px) {
  .container { padding: 0 28px; }

  .philosophy-grid { grid-template-columns: repeat(2, 1fr); }
  .services-index-layout { grid-template-columns: 1fr; gap: 32px; }
  .services-side-index {
    position: static;
    display: flex; gap: 8px; flex-wrap: wrap;
  }
  .services-idx-label { display: none; }
  .services-idx-item {
    border-left: none; padding-left: 0; margin-left: 0;
    border-bottom: 2px solid transparent; padding-bottom: 4px;
  }
  .services-idx-item.active {
    border-bottom-color: var(--green); border-left-color: transparent;
  }

  .about-layout { grid-template-columns: 1fr; gap: 44px; }
  .about-certs { flex-direction: row; flex-wrap: wrap; }
  .cert-card { flex: 1; min-width: 200px; }

  .contact-layout { grid-template-columns: 1fr; gap: 44px; }

  .features-grid { grid-template-columns: 1fr 1fr; }
  .feature-card { border-right: none !important; border-bottom: 1px solid var(--border); }
  .feature-card:nth-child(odd) { border-right: 1px solid var(--border) !important; }
  .feature-card:last-child { border-bottom: none; }
}

@media (max-width: 768px) {
  :root { --section-padding: 76px; }

  .nav-toggle { display: flex; }

  .lang-switch { margin-left: auto; }
  .nav-toggle { margin-left: 12px; }

  .nav-links {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    z-index: 5;
    background: var(--ivory);
    flex-direction: column;
    justify-content: center;
    align-items: center;
    gap: 6px;
  }

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

  .nav-links a {
    color: var(--text-body) !important;
    font-size: 1.05rem;
    padding: 14px 24px;
    letter-spacing: 3px;
    background: transparent !important;
    border: none !important;
    transition: none !important;
  }

  .nav-links a:hover { color: var(--green) !important; }

  .nav-links .nav-cta {
    background: var(--green) !important;
    color: var(--white) !important;
    margin-top: 12px;
  }

  .nav-toggle.active span:nth-child(1) {
    transform: rotate(45deg) translate(5px, 5px);
  }
  .nav-toggle.active span:nth-child(2) { opacity: 0; }
  .nav-toggle.active span:nth-child(3) {
    transform: rotate(-45deg) translate(5px, -5px);
  }

  .nav-container { position: relative; z-index: 10; }

  /* Keep logo, toggle, lang-switch above the full-screen nav overlay */
  .logo { position: relative; z-index: 20; }
  .nav-toggle { position: relative; z-index: 20; }
  .lang-switch { position: relative; z-index: 20; }

  /* Force dark lines when menu is open (X icon visible on ivory bg) */
  .nav-toggle.active span { background: var(--text-dark) !important; }

  /* Give navbar a solid bg when menu is open, disable blur */
  .navbar.menu-open {
    background: var(--ivory) !important;
    backdrop-filter: none !important;
    -webkit-backdrop-filter: none !important;
    box-shadow: none !important;
  }
  .navbar.menu-open .logo-text { color: var(--text-dark) !important; }
  .navbar.menu-open .logo-sub { color: var(--text-muted) !important; }
  .navbar.menu-open .logo-mark { background: var(--green) !important; backdrop-filter: none !important; }
  .navbar.menu-open .lang-btn { color: var(--text-muted) !important; }
  .navbar.menu-open .lang-btn.active { color: var(--green) !important; }

  .hero-content { padding: 140px 0 60px; }
  .hero-eyebrow { margin-bottom: 28px; }
  .hero-desc { margin-bottom: 36px; }
  .hero-scroll { margin-top: 40px; }
  .section-header { margin-bottom: 44px; }

  .philosophy-grid { grid-template-columns: 1fr; gap: 0; background: rgba(255,255,255,0.05); }
  .philosophy-card { padding: 32px 26px; }

  .services-card { grid-template-columns: 1fr; gap: 16px; padding: 32px 24px; }
  .services-card-num { font-size: 2rem; }

  .features-grid { grid-template-columns: 1fr; }
  .feature-card {
    border-right: none !important;
    border-bottom: 1px solid var(--border);
    padding: 30px 26px;
  }

  .contact-form-card { padding: 30px 22px; }
  .form-row { grid-template-columns: 1fr; }

  .footer-top { grid-template-columns: 1fr; gap: 32px; }
  .footer-bottom { flex-direction: column; align-items: center; gap: 4px; text-align: center; }

  .about-certs { flex-direction: column; }
  .cert-card { min-width: auto; }
}

@media (max-width: 480px) {
  .container { padding: 0 18px; }
  .hero-content { padding: 130px 0 48px; }
  .hero-title-zh { letter-spacing: 4px; }
  .hero-title-en { font-size: clamp(1rem, 2.5vw, 1.5rem); }
  .hero-actions { flex-direction: column; align-items: stretch; }
  .btn { justify-content: center; padding: 13px 28px; }
  .about-lead p { font-size: 1.08rem; }
}