/* ========================================
   XS Autoparts — Base / Reset
   ======================================== */

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

html {
  scroll-behavior: smooth;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  background-color: var(--color-bg);
}

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

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

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

ul, ol { list-style: none; }

button {
  font-family: inherit;
  cursor: pointer;
  border: none;
  background: none;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: var(--fw-bold);
  line-height: 1.15;
  letter-spacing: -0.01em;
}

/* Container */
.container {
  max-width: var(--container-width);
  margin: 0 auto;
  padding: var(--container-padding);
}

/* Section Titles — distinctive treatment */
.section-title {
  font-family: var(--font-heading);
  font-size: var(--fs-4xl);
  font-weight: var(--fw-bold);
  text-align: center;
  margin-bottom: 8px;
  color: var(--color-primary);
  text-transform: uppercase;
  letter-spacing: 0.02em;
}

.section-subtitle {
  font-size: var(--fs-lg);
  text-align: center;
  color: var(--color-text-light);
  margin-bottom: 56px;
  font-weight: var(--fw-normal);
}

/* ─── Buttons — bold, confident ─── */
.btn {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: var(--radius-sm);
  font-family: var(--font-heading);
  font-size: var(--fs-base);
  font-weight: var(--fw-semibold);
  letter-spacing: 0.03em;
  text-transform: uppercase;
  transition: all var(--transition-base);
  cursor: pointer;
  border: none;
  white-space: nowrap;
  position: relative;
  overflow: hidden;
}

.btn::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(180deg, rgba(255,255,255,0.12) 0%, transparent 60%);
  pointer-events: none;
}

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

.btn-primary:hover {
  background: var(--color-accent-hover);
  transform: translateY(-2px);
  box-shadow: var(--shadow-accent);
}

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

.btn-whatsapp:hover {
  background: var(--color-whatsapp-hover);
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(37, 211, 102, 0.3);
}

.btn-outline {
  background: transparent;
  color: var(--color-white);
  border: 2px solid rgba(255, 255, 255, 0.3);
}

.btn-outline:hover {
  background: var(--color-white);
  color: var(--color-primary);
  border-color: var(--color-white);
  transform: translateY(-2px);
}

/* ─── Staggered Scroll Reveal ─── */
.reveal {
  opacity: 0;
  transform: translateY(40px);
  transition: opacity 0.7s cubic-bezier(0.4, 0, 0.2, 1),
              transform 0.7s cubic-bezier(0.4, 0, 0.2, 1);
}

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

/* Stagger children */
.reveal.visible .stagger { opacity: 0; animation: staggerIn 0.6s ease forwards; }
.reveal.visible .stagger:nth-child(1) { animation-delay: 0.05s; }
.reveal.visible .stagger:nth-child(2) { animation-delay: 0.1s; }
.reveal.visible .stagger:nth-child(3) { animation-delay: 0.15s; }
.reveal.visible .stagger:nth-child(4) { animation-delay: 0.2s; }
.reveal.visible .stagger:nth-child(5) { animation-delay: 0.25s; }
.reveal.visible .stagger:nth-child(6) { animation-delay: 0.3s; }
.reveal.visible .stagger:nth-child(7) { animation-delay: 0.35s; }
.reveal.visible .stagger:nth-child(8) { animation-delay: 0.4s; }
.reveal.visible .stagger:nth-child(n+9) { animation-delay: 0.45s; }

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

/* ─── Grain Texture Overlay ─── */
body::after {
  content: '';
  position: fixed;
  inset: 0;
  z-index: 9999;
  pointer-events: none;
  opacity: 0.025;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  background-repeat: repeat;
  background-size: 256px;
}

/* ─── Responsive ─── */
@media (max-width: 768px) {
  .section-title { font-size: var(--fs-2xl); margin-bottom: 4px; }
  .section-subtitle { font-size: var(--fs-sm); margin-bottom: 28px; }
  :root { --section-padding: 48px 0; }
  .btn { padding: 12px 24px; font-size: var(--fs-sm); }
}