/* ============================================
   Silver Birch Capital – Premium Design System
   World-class PE firm aesthetic
   ============================================ */

@import url('https://fonts.googleapis.com/css2?family=Playfair+Display:ital,wght@0,400;0,700;1,400;1,700&display=swap');

:root {
  --navy: #0B2545;
  --navy-light: #0f3060;
  --navy-hover: #132f54;
  --navy-deep: #081c36;
  --text-primary: #29303D;
  --text-secondary: #6B7280;
  --text-muted: #9CA3AF;
  --white: #ffffff;
  --bg-warm: #fafaf8;
  --bg-card: #f9fafb;
  --border: #e5e7eb;
  --border-light: #f3f4f6;
  --shadow-sm: 0 1px 3px rgba(0,0,0,0.04);
  --shadow-md: 0 4px 24px rgba(0,0,0,0.06);
  --shadow-lg: 0 12px 48px rgba(0,0,0,0.08);
  --shadow-xl: 0 20px 60px rgba(11,37,69,0.12);
  --ease-out: cubic-bezier(0.16, 1, 0.3, 1);
  --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
}

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

html { scroll-behavior: smooth; }

body {
  font-family: ui-sans-serif, system-ui, -apple-system, BlinkMacSystemFont,
    "Segoe UI", Roboto, "Helvetica Neue", Arial, sans-serif;
  color: var(--text-primary);
  background: var(--white);
  line-height: 1.6;
  -webkit-font-smoothing: antialiased;
  overflow-x: hidden;
}

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

*:focus-visible {
  outline: 2px solid var(--navy);
  outline-offset: 3px;
  border-radius: 3px;
}

::selection {
  background: rgba(11, 37, 69, 0.12);
  color: var(--navy);
}

/* ============================================
   Scroll Progress Bar
   ============================================ */

.scroll-progress {
  position: fixed;
  top: 0;
  left: 0;
  height: 2px;
  background: var(--navy);
  z-index: 200;
  width: 0%;
  transition: width 0.1s linear;
}

/* ============================================
   Entrance Animations
   ============================================ */

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

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

.animate-fade-up {
  opacity: 0;
  animation: fadeUp 0.8s var(--ease-out) forwards;
}

.animate-fade-up.delay-1 { animation-delay: 0.1s; }
.animate-fade-up.delay-2 { animation-delay: 0.2s; }
.animate-fade-up.delay-3 { animation-delay: 0.3s; }
.animate-fade-up.delay-4 { animation-delay: 0.4s; }
.animate-fade-up.delay-5 { animation-delay: 0.5s; }

.reveal {
  opacity: 0;
  transform: translateY(32px);
  transition: opacity 0.7s var(--ease-out), transform 0.7s var(--ease-out);
}

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

.reveal.delay-1 { transition-delay: 0.15s; }
.reveal.delay-2 { transition-delay: 0.3s; }
.reveal.delay-3 { transition-delay: 0.45s; }

/* ============================================
   Header / Navigation
   ============================================ */

.header {
  position: fixed;
  top: 0; left: 0; right: 0;
  z-index: 100;
  background: var(--white);
  border-bottom: 1px solid rgba(0, 0, 0, 0.06);
  transition: background 0.3s ease, box-shadow 0.3s ease;
}

.header.scrolled {
  background: var(--white);
  box-shadow: 0 2px 16px rgba(0, 0, 0, 0.08);
  border-bottom-color: transparent;
}

.header-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  height: 80px;
}

.logo {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  transition: opacity 0.2s ease;
}

.logo:hover { opacity: 0.8; }
.logo img {
  height: 54px;
  width: auto;
  object-fit: contain;
}

.logo-text {
  font-size: 1.15rem;
  font-weight: 700;
  color: var(--navy);
}

.logo-text span {
  font-weight: 400;
  color: var(--text-secondary);
}

.nav-links {
  display: flex;
  align-items: center;
  gap: 2.5rem;
  list-style: none;
}

.nav-links a {
  font-size: 14px;
  font-weight: 400;
  color: var(--text-secondary);
  transition: color 0.25s ease;
  position: relative;
}

.nav-links a::after {
  content: '';
  position: absolute;
  bottom: -4px;
  left: 0;
  width: 0;
  height: 1.5px;
  background: var(--navy);
  transition: width 0.3s var(--ease-out);
}

.nav-links a:hover { color: var(--navy); }
.nav-links a:hover::after { width: 100%; }

.nav-links a.active {
  color: var(--navy);
  font-weight: 600;
}

.nav-links a.active::after { width: 100%; }

.menu-toggle {
  display: none;
  background: none;
  border: none;
  cursor: pointer;
  padding: 0.5rem;
}

.menu-toggle svg {
  width: 24px; height: 24px;
  stroke: var(--navy);
}

/* ============================================
   Birch Tree Background (shared)
   ============================================ */

.birch-section {
  position: relative;
  overflow: hidden;
}

.birch-bg {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background-image: url('images/birch-bg.png');
  background-size: cover;
  background-position: center center;
  background-repeat: no-repeat;
  opacity: 0.7;
  z-index: 0;
}

.birch-overlay {
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(
    rgba(255, 255, 255, 0.15),
    rgba(255, 255, 255, 0.05),
    rgba(255, 255, 255, 0.25)
  );
  z-index: 1;
}

/* ============================================
   Hero Section (Homepage)
   ============================================ */

.hero {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 8rem 2rem 4rem;
  text-align: center;
}

.hero-inner {
  position: relative;
  z-index: 2;
  max-width: 780px;
  margin: 0 auto;
  width: 100%;
}

.hero-tag {
  font-size: 13px;
  font-weight: 500;
  color: rgba(11, 37, 69, 0.5);
  letter-spacing: 2.8px;
  text-transform: uppercase;
  margin-bottom: 32px;
  line-height: 1.6;
}

.hero h1 {
  font-family: 'Playfair Display', serif;
  font-size: 48px;
  font-weight: 700;
  font-style: italic;
  color: var(--navy);
  line-height: 1.15;
  margin-bottom: 28px;
}

.hero-subtitle {
  font-size: 20px;
  font-weight: 400;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 12px;
}

.hero-body {
  font-size: 16px;
  font-weight: 400;
  color: var(--text-muted);
  line-height: 1.65;
  margin-bottom: 40px;
  max-width: 620px;
  margin-left: auto;
  margin-right: auto;
}

.hero-buttons {
  display: flex;
  gap: 16px;
  flex-wrap: wrap;
  justify-content: center;
}

/* ============================================
   Subpage Hero (Approach / Contact)
   ============================================ */

.subpage-hero {
  padding: 10rem 2rem 5rem;
  background: var(--navy);
  text-align: center;
  position: relative;
  overflow: hidden;
}

/* Subtle gradient overlay for depth */
.subpage-hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: radial-gradient(ellipse at 50% 0%, rgba(255,255,255,0.05) 0%, transparent 70%);
  pointer-events: none;
}

.subpage-hero-inner {
  position: relative;
  z-index: 1;
  max-width: 700px;
  margin: 0 auto;
}

.subpage-tag {
  font-size: 12px;
  font-weight: 500;
  color: rgba(255, 255, 255, 0.55);
  letter-spacing: 3px;
  text-transform: uppercase;
  margin-bottom: 20px;
}

.subpage-hero h1 {
  font-family: 'Playfair Display', serif;
  font-size: 48px;
  font-weight: 700;
  font-style: italic;
  color: var(--white);
  margin-bottom: 20px;
  line-height: 1.15;
}

.subpage-desc {
  font-size: 18px;
  color: rgba(255, 255, 255, 0.65);
  line-height: 1.7;
}

.hide-mobile { display: inline; }

/* ============================================
   Buttons
   ============================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 14px 32px;
  font-size: 14px;
  font-weight: 500;
  font-family: inherit;
  border-radius: 6px;
  cursor: pointer;
  border: none;
  text-decoration: none;
  transition: all 0.25s var(--ease-smooth);
}

.btn:active { transform: scale(0.97); }

.btn-primary {
  background: var(--navy);
  color: var(--white);
}

.btn-primary:hover {
  background: var(--navy-hover);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(11, 37, 69, 0.25);
}

.btn-primary:active {
  transform: translateY(0) scale(0.98);
  box-shadow: 0 2px 8px rgba(11, 37, 69, 0.2);
}

.btn-arrow {
  display: inline-block;
  transition: transform 0.3s var(--ease-out);
  font-size: 16px;
}

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

.btn-outline {
  background: transparent;
  color: var(--navy);
  border: 1px solid rgba(11, 37, 69, 0.2);
}

.btn-outline:hover {
  border-color: var(--navy);
  background: var(--navy);
  color: var(--white);
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(11, 37, 69, 0.15);
}

/* ============================================
   Pillars (Approach Page Cards)
   ============================================ */

.pillars-section {
  padding: 5rem 2rem 6rem;
  background: var(--bg-warm);
}

.pillars-intro {
  max-width: 1100px;
  margin: 0 auto 3rem;
  text-align: center;
  font-size: 17px;
  line-height: 1.7;
  color: var(--text-secondary);
}

.pillars-grid {
  max-width: 1100px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 24px;
}

.pillar {
  padding: 36px 32px;
  border-radius: 14px;
  background: var(--white);
  border: 1px solid var(--border-light);
  transition: transform 0.4s var(--ease-out), box-shadow 0.4s var(--ease-out);
  position: relative;
}

.pillar:hover {
  transform: translateY(-6px);
  box-shadow: var(--shadow-xl);
}

/* Navy accent line on top of each card */
.pillar::before {
  content: '';
  position: absolute;
  top: 0;
  left: 32px;
  right: 32px;
  height: 3px;
  background: var(--navy);
  border-radius: 0 0 3px 3px;
  opacity: 0.15;
  transition: opacity 0.3s ease;
}

.pillar:hover::before {
  opacity: 0.4;
}

/* Pillar icon */
.pillar-icon {
  width: 52px;
  height: 52px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: 28px;
  background: rgba(11, 37, 69, 0.06);
  transition: transform 0.3s var(--ease-out);
}

.pillar:hover .pillar-icon { transform: scale(1.05); }

.pillar-icon svg {
  width: 24px; height: 24px;
  stroke: var(--navy);
  fill: none;
  stroke-width: 1.5;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.pillar h3 {
  font-family: 'Playfair Display', serif;
  font-size: 20px;
  font-weight: 700;
  margin-bottom: 14px;
  color: var(--navy);
  line-height: 1.3;
}

.pillar p {
  font-size: 14.5px;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 24px;
}

/* Checkmark list */
.pillar-checks { list-style: none; padding: 0; }

.pillar-checks li {
  padding: 6px 0;
  font-size: 14px;
  color: var(--text-secondary);
  display: flex;
  align-items: flex-start;
  gap: 10px;
  line-height: 1.5;
}

.pillar-checks li svg {
  width: 17px; height: 17px;
  flex-shrink: 0;
  margin-top: 2px;
  stroke: var(--text-muted);
  fill: none;
  stroke-width: 1.5;
}

/* ============================================
   Approach CTA Section
   ============================================ */

.approach-cta {
  padding: 6rem 2rem;
  text-align: center;
}

.approach-cta-inner {
  position: relative;
  z-index: 2;
  max-width: 560px;
  margin: 0 auto;
}

.approach-cta h2 {
  font-family: 'Playfair Display', serif;
  font-size: 32px;
  font-weight: 700;
  font-style: italic;
  color: var(--navy);
  margin-bottom: 14px;
}

.approach-cta p {
  font-size: 16px;
  color: var(--text-secondary);
  margin-bottom: 32px;
  line-height: 1.6;
}

/* ============================================
   Contact Page
   ============================================ */

.contact-body {
  padding: 5rem 2rem 6rem;
  background: var(--bg-warm);
}

.contact-grid {
  max-width: 960px;
  margin: 0 auto;
  display: grid;
  grid-template-columns: 1fr 1.15fr;
  gap: 4rem;
  align-items: start;
}

.contact-info h2 {
  font-family: 'Playfair Display', serif;
  font-size: 28px;
  font-weight: 700;
  color: var(--navy);
  margin-bottom: 16px;
  line-height: 1.25;
}

.contact-info > p {
  font-size: 15px;
  line-height: 1.7;
  color: var(--text-secondary);
  margin-bottom: 40px;
}

.contact-detail {
  display: flex;
  align-items: flex-start;
  gap: 16px;
  margin-bottom: 24px;
}

.contact-detail-icon {
  width: 44px;
  height: 44px;
  border-radius: 10px;
  background: rgba(11, 37, 69, 0.06);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.contact-detail-icon svg {
  width: 20px;
  height: 20px;
  color: var(--navy);
}

.contact-detail-label {
  display: block;
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 1px;
  text-transform: uppercase;
  color: var(--text-muted);
  margin-bottom: 4px;
}

.contact-detail-value {
  font-size: 15px;
  color: var(--navy);
  font-weight: 500;
}

a.contact-detail-value {
  transition: opacity 0.2s ease;
}

a.contact-detail-value:hover {
  opacity: 0.7;
}

/* Contact Form Card */
.contact-card {
  background: var(--white);
  border-radius: 14px;
  padding: 40px;
  box-shadow: var(--shadow-lg);
  border: 1px solid var(--border-light);
}

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

.form-group label {
  display: block;
  font-size: 12px;
  font-weight: 600;
  color: var(--text-primary);
  letter-spacing: 1px;
  text-transform: uppercase;
  margin-bottom: 8px;
}

.form-group label .optional {
  font-weight: 400;
  color: var(--text-muted);
  text-transform: uppercase;
  letter-spacing: 0.5px;
}

.form-group input,
.form-group textarea {
  width: 100%;
  padding: 12px 16px;
  font-size: 14px;
  font-family: inherit;
  border: 1px solid var(--border);
  border-radius: 8px;
  background: var(--white);
  color: var(--navy);
  transition: border-color 0.25s ease, box-shadow 0.25s ease;
}

.form-group input:hover,
.form-group textarea:hover {
  border-color: #d1d5db;
}

.form-group input:focus,
.form-group textarea:focus {
  outline: none;
  border-color: var(--navy);
  box-shadow: 0 0 0 3px rgba(11, 37, 69, 0.08);
}

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

.form-group textarea {
  min-height: 130px;
  max-height: 300px;
  resize: vertical;
}

.form-group input:invalid:not(:placeholder-shown),
.form-group textarea:invalid:not(:placeholder-shown) {
  border-color: #ef4444;
  box-shadow: 0 0 0 3px rgba(239, 68, 68, 0.08);
}

.form-submit { margin-top: 8px; }
.form-submit .btn { width: 100%; }

/* Form success state */
.form-success {
  text-align: center;
  padding: 3rem 1rem;
}

.form-success svg {
  margin: 0 auto 16px;
}

.form-success h2 {
  font-family: 'Playfair Display', serif;
  font-size: 24px;
  color: var(--navy);
  margin-bottom: 8px;
  font-style: italic;
}

.form-success p {
  color: var(--text-secondary);
  font-size: 15px;
  line-height: 1.6;
}

/* ============================================
   Footer
   ============================================ */

.footer {
  background: var(--navy);
  color: rgba(255, 255, 255, 0.5);
  font-size: 13px;
}

.footer-inner {
  max-width: 1200px;
  margin: 0 auto;
  padding: 1.25rem 2rem;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 1.5rem;
}

.footer-logo {
  font-family: 'Playfair Display', serif;
  font-size: 14px;
  font-weight: 700;
  color: rgba(255, 255, 255, 0.85);
  letter-spacing: 0.02em;
  white-space: nowrap;
}

.footer-nav {
  display: flex;
  gap: 1.5rem;
}

.footer-nav a {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.45);
  transition: color 0.2s ease;
}

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

.footer-right {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  white-space: nowrap;
}

.footer-right a {
  font-size: 13px;
  color: rgba(255, 255, 255, 0.45);
  transition: color 0.2s ease;
}

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

.footer-divider {
  color: rgba(255, 255, 255, 0.2);
}

.footer-right span {
  color: rgba(255, 255, 255, 0.3);
}

/* ============================================
   Mobile Responsive
   ============================================ */

@media (max-width: 768px) {
  .header-inner { padding: 0 1.25rem; }

  .nav-links {
    display: none;
    position: absolute;
    top: 80px;
    left: 0; right: 0;
    background: var(--white);
    flex-direction: column;
    padding: 1.5rem;
    gap: 1rem;
    border-bottom: 1px solid var(--border);
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
  }

  .nav-links.open { display: flex; }
  .menu-toggle { display: block; }

  .hero {
    min-height: auto;
    padding: 7rem 1.25rem 3rem;
  }

  .hero h1 { font-size: 32px; }
  .hero-subtitle { font-size: 17px; }

  .subpage-hero { padding: 7rem 1.25rem 3.5rem; }
  .subpage-hero h1 { font-size: 32px; }
  .subpage-desc { font-size: 16px; }
  .hide-mobile { display: none; }

  .pillars-section { padding: 3rem 1.25rem 4rem; }
  .pillars-grid { grid-template-columns: 1fr; gap: 20px; }
  .pillar { padding: 28px 24px; }

  .contact-body { padding: 2.5rem 1.25rem 4rem; }
  .contact-grid {
    grid-template-columns: 1fr;
    gap: 2.5rem;
  }
  .contact-card { padding: 28px 24px; }

  .approach-cta { padding: 4rem 1.25rem; }
  .approach-cta h2 { font-size: 26px; }

  .footer-inner {
    flex-direction: column;
    text-align: center;
    gap: 0.75rem;
    padding: 1.25rem;
  }

  .footer-right {
    flex-direction: column;
    gap: 0.25rem;
  }

  .footer-divider { display: none; }
}

@media (max-width: 1024px) and (min-width: 769px) {
  .pillars-grid { grid-template-columns: 1fr 1fr; }

  .contact-grid { gap: 2.5rem; }
}