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

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

body {
  font-family: var(--font-body);
  font-size: var(--text-base);
  line-height: 1.7;
  color: var(--color-text);
  background-color: var(--color-bg);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  overflow-x: hidden;
}

/* Subtle noise grain overlay on body */
body::before {
  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 256px;
}

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

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

a:hover {
  color: var(--color-link-hover);
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-heading);
  font-weight: 400;
  line-height: 1.2;
  color: var(--color-white);
  letter-spacing: -0.01em;
}

h1 {
  font-size: var(--text-3xl);
  letter-spacing: -0.02em;
}

h2 {
  font-size: var(--text-2xl);
  letter-spacing: -0.015em;
}

h3 { font-size: var(--text-xl); }
h4 { font-size: var(--text-lg); }

p {
  margin-bottom: var(--space-4);
}

p:last-child {
  margin-bottom: 0;
}

ul, ol {
  padding-left: var(--space-6);
  margin-bottom: var(--space-4);
}

li {
  margin-bottom: var(--space-2);
}

li:last-child {
  margin-bottom: 0;
}

code {
  font-family: var(--font-mono);
  font-size: 0.88em;
  background-color: rgba(110, 193, 228, 0.1);
  color: var(--color-sky-bright);
  padding: 0.15em 0.45em;
  border-radius: var(--radius-sm);
  border: 1px solid rgba(110, 193, 228, 0.12);
}

pre {
  background-color: var(--color-bg-raised);
  border: 1px solid var(--color-border);
  padding: var(--space-5);
  border-radius: var(--radius-md);
  overflow-x: auto;
  margin-bottom: var(--space-4);
}

pre code {
  background: none;
  padding: 0;
  border: none;
  color: var(--color-text);
}

blockquote {
  border-left: 3px solid var(--color-sky);
  padding-left: var(--space-4);
  margin: var(--space-6) 0;
  color: var(--color-text-muted);
  font-style: italic;
}

strong {
  font-weight: 700;
  color: var(--color-white);
}

::selection {
  background-color: rgba(110, 193, 228, 0.3);
  color: var(--color-white);
}

/* Scroll-triggered reveal animation */
@keyframes fadeInUp {
  from {
    opacity: 0;
    transform: translateY(24px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

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

@keyframes shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-20px);
  }
  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes pulse-glow {
  0%, 100% { opacity: 0.6; }
  50% { opacity: 1; }
}

@keyframes progress-shimmer {
  0% { background-position: -200% 0; }
  100% { background-position: 200% 0; }
}

.animate-in {
  animation: fadeInUp 0.7s cubic-bezier(0.22, 1, 0.36, 1) both;
}

/* Reading progress bar (article/post pages) */
.reading-progress {
  position: fixed;
  top: 0;
  left: 0;
  width: 0%;
  height: 3px;
  z-index: 200;
  background: linear-gradient(90deg, var(--color-sky), var(--color-green), var(--color-sky));
  background-size: 200% 100%;
  animation: progress-shimmer 3s ease-in-out infinite;
  box-shadow: 0 0 10px rgba(110, 193, 228, 0.5), 0 0 30px rgba(110, 193, 228, 0.2);
  transition: width 50ms linear;
  pointer-events: none;
}

/* Back to top button */
.back-to-top {
  position: fixed;
  bottom: var(--space-8);
  right: var(--space-6);
  z-index: 90;
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: rgba(13, 17, 23, 0.85);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-muted);
  cursor: pointer;
  opacity: 0;
  visibility: hidden;
  transform: translateY(12px);
  transition: opacity var(--transition-base), visibility var(--transition-base),
    transform var(--transition-base), color var(--transition-fast),
    border-color var(--transition-fast), box-shadow var(--transition-fast);
}

.back-to-top.is-visible {
  opacity: 1;
  visibility: visible;
  transform: translateY(0);
}

.back-to-top:hover {
  color: var(--color-sky);
  border-color: rgba(110, 193, 228, 0.3);
  box-shadow: var(--shadow-md), 0 0 20px rgba(110, 193, 228, 0.15);
  transform: translateY(-2px);
}

.back-to-top svg {
  width: 20px;
  height: 20px;
  fill: currentColor;
}