/* =========================================================
   Delta Company SRL — Design System
   ========================================================= */
:root {
  --delta-dark: #0F0E0C;
  --delta-ink: #141312;
  --delta-charcoal: #1C1917;
  --delta-fire: #A02121;        /* Rosso brand (lettere logo) - toned down */
  --delta-red-deep: #7A1818;    /* Rosso scuro */
  --delta-amber: #C9884A;       /* Terracotta più sobrio */
  --delta-gold: #C9A961;        /* Oro editoriale (meno saturo) */
  --delta-cream: #FAFAF9;
  --delta-paper: #F1ECE2;       /* NEW: Paper beige editoriale */
  --delta-paper-warm: #E8E1D3;  /* NEW: Paper più caldo */
  --delta-stone: #78716C;
  --delta-slate: #57534E;       /* NEW: Grigio istituzionale */
  --delta-light: #F5F5F4;
  --delta-border: #E7E5E4;
  --delta-hairline: rgba(20,19,18,0.12);
}

* { -webkit-font-smoothing: antialiased; -moz-osx-font-smoothing: grayscale; }

html { scroll-behavior: smooth; }

body {
  font-family: 'Inter', system-ui, sans-serif;
  color: var(--delta-charcoal);
  background-color: var(--delta-cream);
  overflow-x: hidden;
}

h1, h2, h3, h4, h5, h6, .font-display {
  font-family: 'Plus Jakarta Sans', system-ui, sans-serif;
  letter-spacing: -0.025em;
}

/* Serif editoriale per numeri e citazioni istituzionali */
.font-serif {
  font-family: 'Fraunces', 'Times New Roman', Georgia, serif;
  font-optical-sizing: auto;
  font-variation-settings: "SOFT" 30, "WONK" 0;
  letter-spacing: -0.02em;
}

.institutional-num {
  font-family: 'Plus Jakarta Sans', system-ui, sans-serif;
  font-feature-settings: "tnum", "lnum";
  font-variant-numeric: tabular-nums lining-nums;
  font-weight: 800;
  letter-spacing: -0.04em;
}

/* Institutional badge - sharp, sober, no gradient */
.badge-inst {
  display: inline-flex;
  align-items: center;
  gap: 0.6rem;
  padding: 0.45rem 0.85rem;
  border: 1px solid currentColor;
  font-size: 0.7rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  line-height: 1;
}

/* Editorial paper section */
.section-paper { background: var(--delta-paper); }
.section-paper-warm { background: var(--delta-paper-warm); }

/* Thin hairline */
.hairline { height: 1px; background: var(--delta-hairline); }
.hairline-white { height: 1px; background: rgba(255,255,255,0.15); }

/* Institutional caption */
.caption {
  font-size: 0.72rem;
  font-weight: 600;
  letter-spacing: 0.22em;
  text-transform: uppercase;
  color: var(--delta-slate);
}
.caption-red { color: var(--delta-fire); }

/* ----- Hero gradient overlay ----- */
.hero-overlay {
  background: linear-gradient(115deg, rgba(15,14,12,0.92) 0%, rgba(28,25,23,0.75) 55%, rgba(234,88,12,0.25) 100%);
}

.hero-grid {
  background-image:
    linear-gradient(rgba(255,255,255,0.04) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255,255,255,0.04) 1px, transparent 1px);
  background-size: 60px 60px;
}

/* ----- Buttons ----- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  padding: 0.95rem 1.75rem;
  border-radius: 0.5rem;
  font-weight: 600;
  font-size: 0.95rem;
  letter-spacing: -0.01em;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  white-space: nowrap;
  cursor: pointer;
}
.btn-primary {
  background: var(--delta-fire);
  color: white;
  box-shadow: 0 4px 14px rgba(178,41,41,0.35);
}
.btn-primary:hover {
  background: var(--delta-red-deep);
  transform: translateY(-2px);
  box-shadow: 0 8px 24px rgba(178,41,41,0.45);
}
.btn-secondary {
  background: white;
  color: var(--delta-dark);
  border: 1px solid var(--delta-border);
}
.btn-secondary:hover {
  background: var(--delta-light);
  border-color: var(--delta-stone);
}
.btn-dark {
  background: var(--delta-dark);
  color: white;
}
.btn-dark:hover {
  background: var(--delta-charcoal);
  transform: translateY(-2px);
}
.btn-ghost {
  background: transparent;
  color: white;
  border: 1px solid rgba(255,255,255,0.25);
}
.btn-ghost:hover {
  background: rgba(255,255,255,0.08);
  border-color: rgba(255,255,255,0.5);
}

/* ----- Section helpers ----- */
.section { padding: 6rem 0; }
.section-sm { padding: 4rem 0; }
.container-x { max-width: 1280px; margin: 0 auto; padding: 0 1.5rem; }

.eyebrow {
  display: inline-flex;
  align-items: center;
  gap: 0.75rem;
  font-size: 0.72rem;
  font-weight: 700;
  letter-spacing: 0.28em;
  text-transform: uppercase;
  color: var(--delta-fire);
}
.eyebrow::before {
  content: '';
  width: 44px;
  height: 1px;
  background: var(--delta-fire);
}

.heading-xl { font-size: clamp(2.5rem, 5.5vw, 4.5rem); line-height: 1.02; font-weight: 800; }
.heading-lg { font-size: clamp(2rem, 4vw, 3.25rem); line-height: 1.05; font-weight: 700; }
.heading-md { font-size: clamp(1.5rem, 2.5vw, 2.25rem); line-height: 1.15; font-weight: 700; }

/* ----- Card hover ----- */
.card-hover {
  transition: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}
.card-hover:hover {
  transform: translateY(-6px);
  box-shadow: 0 24px 50px -12px rgba(15,14,12,0.18);
}

/* ----- Number animation ----- */
.stat-number {
  font-feature-settings: "tnum";
  font-variant-numeric: tabular-nums;
}

/* ----- Marquee ----- */
@keyframes marquee {
  0% { transform: translateX(0); }
  100% { transform: translateX(-50%); }
}
.marquee {
  display: flex;
  gap: 4rem;
  animation: marquee 30s linear infinite;
  width: max-content;
}

/* ----- Reveal on scroll ----- */
.reveal {
  opacity: 0;
  transform: translateY(24px);
  transition: all 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}
.reveal.is-visible {
  opacity: 1;
  transform: translateY(0);
}

/* ----- Nav ----- */
.nav-link {
  position: relative;
  font-size: 0.92rem;
  font-weight: 500;
  color: var(--delta-charcoal);
  transition: color 0.2s ease;
}
.nav-link::after {
  content: '';
  position: absolute;
  left: 0; bottom: -6px;
  width: 0; height: 2px;
  background: var(--delta-fire);
  transition: width 0.25s ease;
}
.nav-link:hover { color: var(--delta-fire); }
.nav-link:hover::after,
.nav-link.active::after { width: 100%; }
.nav-link.active { color: var(--delta-fire); }

/* ----- Form ----- */
.form-input {
  width: 100%;
  padding: 0.85rem 1rem;
  background: white;
  border: 1px solid var(--delta-border);
  border-radius: 0.5rem;
  font-size: 0.95rem;
  transition: all 0.2s ease;
  font-family: inherit;
}
.form-input:focus {
  outline: none;
  border-color: var(--delta-fire);
  box-shadow: 0 0 0 4px rgba(178,41,41,0.12);
}
.form-label {
  display: block;
  font-size: 0.85rem;
  font-weight: 600;
  margin-bottom: 0.4rem;
  color: var(--delta-charcoal);
}

/* ----- Mobile menu ----- */
.mobile-menu {
  position: fixed;
  inset: 0;
  background: var(--delta-dark);
  z-index: 100;
  transform: translateX(100%);
  transition: transform 0.4s cubic-bezier(0.65, 0, 0.35, 1);
}
.mobile-menu.open { transform: translateX(0); }

/* ----- Decorative flame icon ----- */
.flame-bg {
  position: absolute;
  opacity: 0.04;
  pointer-events: none;
  user-select: none;
}

/* ----- Specs grid ----- */
.spec-row {
  display: flex;
  justify-content: space-between;
  padding: 0.85rem 0;
  border-bottom: 1px solid var(--delta-border);
  font-size: 0.92rem;
}
.spec-row:last-child { border-bottom: none; }
.spec-row span:first-child { color: var(--delta-stone); }
.spec-row span:last-child { font-weight: 600; color: var(--delta-dark); }

/* ----- Footer ----- */
.footer-link {
  color: rgba(250,250,249,0.65);
  font-size: 0.9rem;
  transition: color 0.2s ease;
}
.footer-link:hover { color: var(--delta-fire); }

/* Scrollbar */
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--delta-light); }
::-webkit-scrollbar-thumb { background: var(--delta-stone); border-radius: 5px; }
::-webkit-scrollbar-thumb:hover { background: var(--delta-fire); }