/* css/shared.css */
/* Inter loaded via <link> in HTML for non-blocking font delivery */

*, *::before, *::after { box-sizing: border-box; margin: 0; padding: 0; }
html { scroll-behavior: smooth; }
img { display: block; max-width: 100%; }
a { color: inherit; text-decoration: none; }
button { cursor: pointer; border: none; background: none; font: inherit; }
ul { list-style: none; }

:root {
  --bg:         #0D0D0D;
  --surface:    #161616;
  --surface2:   #1E1E1E;
  --border:     #252525;
  --blue:       #2563EB;
  --blue-hover: #3B7BFF;
  --white:      #FFFFFF;
  --muted:      #9CA3AF;
  --font:       'Inter', sans-serif;
  --radius:     12px;
  --transition: 0.25s ease;
}

body {
  font-family: var(--font);
  background: var(--bg);
  color: var(--white);
  line-height: 1.6;
  overflow-x: hidden;
}

.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 20px;
}

.btn-primary {
  display: inline-block;
  background: var(--blue);
  color: var(--white);
  padding: 16px 36px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: 1rem;
  letter-spacing: 0.02em;
  transition: background var(--transition), transform var(--transition);
}
.btn-primary:hover { background: var(--blue-hover); transform: translateY(-2px); }
.btn-primary:active { transform: translateY(0); }

/* Fade-in animation triggered by IntersectionObserver */
.fade-in { opacity: 0; transform: translateY(24px); transition: opacity 0.6s ease, transform 0.6s ease; }
.fade-in.visible { opacity: 1; transform: none; }

/* Section padding */
.section { padding: 80px 0; }
.section-title {
  font-size: clamp(1.75rem, 4vw, 2.5rem);
  font-weight: 900;
  margin-bottom: 48px;
  line-height: 1.2;
}
.section-title span { color: var(--blue); }

/* Form */
.form-group { display: flex; flex-direction: column; gap: 16px; }
.form-group input {
  background: var(--surface2);
  border: 1px solid var(--border);
  border-radius: var(--radius);
  color: var(--white);
  font-family: var(--font);
  font-size: 1rem;
  padding: 16px 20px;
  outline: none;
  transition: border-color var(--transition);
}
.form-group input:focus { border-color: var(--blue); }
.form-group input::placeholder { color: var(--muted); }

.form-message { font-size: 0.9rem; margin-top: 8px; min-height: 20px; }
.form-message.success { color: #34D399; }
.form-message.error { color: #F87171; }

/* Scrollbar */
::-webkit-scrollbar { width: 6px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--border); border-radius: 3px; }

/* Accessibility: Focus visible for keyboard users */
.btn-primary:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
}
.form-group input:focus-visible {
  outline: 2px solid var(--blue);
  outline-offset: 2px;
}

/* Accessibility: Respect prefers-reduced-motion */
@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* Accessibility: Text selection styling */
::selection {
  background: var(--blue);
  color: var(--white);
}