/* ================================================
   Ubden® Base — reset, typography, utilities
   ================================================ */

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

html {
  scroll-behavior: smooth;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-body);
  font-size: var(--fs-base);
  line-height: 1.65;
  color: var(--text);
  background: var(--bg);
  overflow-x: hidden;
  transition: background-color 0.4s ease, color 0.4s ease;
}

img, svg, video, canvas { display: block; max-width: 100%; }
img { height: auto; }

a { color: var(--accent); text-decoration: none; }
a:hover { text-decoration: none; }

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

ul, ol { list-style: none; }

h1, h2, h3, h4, h5 {
  font-family: var(--font-heading);
  font-weight: 700;
  line-height: 1.15;
  letter-spacing: -0.02em;
}

::selection { background: var(--brand-purple); color: #fff; }

/* Scrollbar */
::-webkit-scrollbar { width: 10px; }
::-webkit-scrollbar-track { background: var(--bg); }
::-webkit-scrollbar-thumb { background: var(--scrollbar-thumb); border-radius: 5px; }

:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
  border-radius: 4px;
}

/* Layout */
.container {
  width: 100%;
  max-width: var(--container);
  margin-inline: auto;
  padding-inline: clamp(1.25rem, 4vw, 2.5rem);
}

.section { padding-block: var(--space-section); position: relative; }
.section-alt { background: var(--bg-alt); }

.section-header { text-align: center; max-width: 820px; margin: 0 auto var(--space-5); }
.section-title {
  font-family: var(--font-display);
  font-weight: 800;
  font-size: var(--fs-h2);
  letter-spacing: -0.01em;
  margin-bottom: var(--space-2);
}
.section-subtitle {
  font-size: var(--fs-sm);
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.18em;
  color: var(--accent);
  margin-bottom: var(--space-2);
}
.section-intro { color: var(--text-muted); font-size: var(--fs-lead); }

.gradient-text {
  background: var(--gradient-brand);
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
}
.gradient-text-animated {
  background: linear-gradient(120deg, var(--brand-cyan), var(--brand-purple), var(--brand-green), var(--brand-cyan));
  background-size: 300% 100%;
  -webkit-background-clip: text;
  background-clip: text;
  -webkit-text-fill-color: transparent;
  color: transparent;
  animation: gradientShift 6s ease-in-out infinite;
}

.text-muted { color: var(--text-muted); }
.text-center { text-align: center; }

.visually-hidden {
  position: absolute;
  width: 1px; height: 1px;
  clip-path: inset(50%);
  overflow: hidden;
  white-space: nowrap;
}

.skip-link {
  position: fixed;
  top: -100px;
  left: 1rem;
  z-index: calc(var(--z-loader) + 1);
  padding: 0.6rem 1.2rem;
  background: var(--accent);
  color: var(--accent-contrast);
  border-radius: var(--radius-sm);
  font-weight: 600;
  transition: top 0.2s ease;
}
.skip-link:focus { top: 1rem; }