/* ==========================================================================
   PALAKURLA SHIVAKUMAR - CYBERSECURITY PORTFOLIO
   Core Design System & Tokens
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Plus+Jakarta+Sans:ital,wght@0,300;0,400;0,500;0,600;0,700;0,800;1,400;1,600&family=Space+Grotesk:wght@400;500;600;700&family=JetBrains+Mono:wght@400;500;600&display=swap');

:root {
  /* Refined executive white theme */
  --bg-primary: #f4f7fb;
  --bg-secondary: #edf3ff;
  --bg-tertiary: #f7faff;
  --bg-card: rgba(255, 255, 255, 0.96);
  --bg-card-hover: rgba(250, 252, 255, 1);
  --bg-glass: rgba(255, 255, 255, 0.82);
  --bg-glass-elevated: rgba(255, 255, 255, 0.98);

  /* Borders & Dividers */
  --border-subtle: rgba(15, 23, 42, 0.08);
  --border-medium: rgba(37, 99, 235, 0.18);
  --border-active: rgba(30, 64, 175, 0.32);
  --border-glow: rgba(37, 99, 235, 0.18);

  /* Primary Accent & Corporate Glows */
  --accent-cyan: #1f5ae5;
  --accent-blue: #183ec9;
  --accent-sky: #3d7af7;
  --accent-navy: #111827;
  --accent-emerald: #10b981;
  --accent-amber: #f59e0b;
  --accent-purple: #6855d8;

  /* Gradients */
  --grad-cyan-blue: linear-gradient(135deg, #0f172a 0%, #1d4ed8 52%, #3b82f6 100%);
  --grad-surface: linear-gradient(180deg, rgba(255, 255, 255, 0.98) 0%, rgba(246, 249, 254, 0.96) 100%);
  --grad-glow: radial-gradient(circle at 50% 0%, rgba(59, 130, 246, 0.10) 0%, transparent 70%);
  --grad-badge: linear-gradient(135deg, rgba(37, 99, 235, 0.08), rgba(148, 163, 184, 0.06));

  /* Typography */
  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-accent: #1d4ed8;
  --text-highlight: #1f5ae5;

  --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Space Grotesk', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Shadows & Glows */
  --shadow-sm: 0 8px 22px rgba(15, 23, 42, 0.06);
  --shadow-md: 0 18px 40px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 30px 65px rgba(15, 23, 42, 0.1);
  --glow-cyan-sm: 0 0 12px rgba(37, 99, 235, 0.08);
  --glow-cyan-md: 0 0 20px rgba(37, 99, 235, 0.1);
  --glow-cyan-lg: 0 0 26px rgba(37, 99, 235, 0.12);

  --font-sans: 'Plus Jakarta Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-display: 'Space Grotesk', sans-serif;
  --font-mono: 'JetBrains Mono', monospace;

  /* Shadows & Glows */
  --shadow-sm: 0 2px 8px rgba(15, 23, 42, 0.05);
  --shadow-md: 0 10px 24px rgba(15, 23, 42, 0.08);
  --shadow-lg: 0 18px 40px rgba(15, 23, 42, 0.12);
  --glow-cyan-sm: 0 0 16px rgba(37, 99, 235, 0.10);
  --glow-cyan-md: 0 0 30px rgba(37, 99, 235, 0.12);
  --glow-cyan-lg: 0 0 50px rgba(37, 99, 235, 0.14);

  /* Transitions & Radii */
  --radius-xs: 4px;
  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 18px;
  --radius-full: 9999px;

  --transition-fast: 0.2s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-normal: 0.35s cubic-bezier(0.16, 1, 0.3, 1);
  --transition-smooth: 0.5s cubic-bezier(0.16, 1, 0.3, 1);

  /* Layout */
  --container-max: 1200px;
  --header-height: 76px;
}

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

html {
  scroll-behavior: smooth;
  font-size: 16px;
  color-scheme: light;
}

body {
  font-family: var(--font-sans);
  background: #ffffff;
  color: var(--text-primary);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  letter-spacing: -0.01em;
}

/* Clean minimal background */
#cyber-canvas {
  display: none;
}

.ambient-grid {
  display: none;
}

.ambient-glow-top {
  display: none;
}

/* Layout Utilities */
.container {
  width: 100%;
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: 1.5rem;
  padding-right: 1.5rem;
  position: relative;
  z-index: 1;
}

.section {
  padding-top: 6.5rem;
  padding-bottom: 6.5rem;
  position: relative;
}

.section-tight {
  padding-top: 4.5rem;
  padding-bottom: 4.5rem;
}

/* Section Header Structure */
.section-header {
  text-align: center;
  max-width: 760px;
  margin-left: auto;
  margin-right: auto;
  margin-bottom: 4rem;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  padding: 0.35rem 0.9rem;
  border-radius: var(--radius-full);
  background: rgba(37, 99, 235, 0.06);
  border: 1px solid rgba(37, 99, 235, 0.15);
  color: var(--accent-cyan);
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  margin-bottom: 1.25rem;
}

.section-tag svg {
  width: 14px;
  height: 14px;
}

.section-title {
  font-family: var(--font-display);
  font-size: clamp(2rem, 3.8vw, 2.75rem);
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.2;
  margin-bottom: 1rem;
  letter-spacing: -0.02em;
}

.section-title .text-gradient {
  background: var(--grad-cyan-blue);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.section-subtitle {
  color: var(--text-secondary);
  font-size: 1.05rem;
  line-height: 1.6;
}

/* Typography Hierarchy */
h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  color: var(--text-primary);
  line-height: 1.25;
}

p {
  color: var(--text-secondary);
}

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

a:hover {
  color: var(--accent-cyan);
}

ul {
  list-style: none;
}

/* Common Animations */
.fade-in-up {
  opacity: 0;
  transform: translateY(24px);
  transition: opacity 0.7s cubic-bezier(0.16, 1, 0.3, 1), transform 0.7s cubic-bezier(0.16, 1, 0.3, 1);
}

.fade-in-up.visible {
  opacity: 1;
  transform: translateY(0);
}

/* Selection */
::selection {
  background: rgba(37, 99, 235, 0.18);
  color: var(--text-primary);
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}

::-webkit-scrollbar-track {
  background: var(--bg-primary);
}

::-webkit-scrollbar-thumb {
  background: var(--bg-tertiary);
  border-radius: 4px;
  border: 1px solid var(--border-subtle);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--accent-blue);
}