/* ==========================================================================
   Dineshkumar S - Cybersecurity Portfolio Design System
   ========================================================================== */

@import url('https://fonts.googleapis.com/css2?family=Fira+Code:wght@400;500;600&family=Plus+Jakarta+Sans:wght@300;400;500;600;700;800&display=swap');

:root {
  /* Dark Cyber Theme (Default) */
  --bg-base: #080c14;
  --bg-surface: #0e1524;
  --bg-card: rgba(16, 24, 40, 0.75);
  --bg-card-hover: rgba(22, 33, 56, 0.9);
  --bg-glass: rgba(14, 21, 36, 0.75);
  --bg-elevated: #162035;

  --border-subtle: rgba(148, 163, 184, 0.12);
  --border-glow: rgba(16, 185, 129, 0.35);
  --border-highlight: rgba(6, 182, 212, 0.35);

  --accent-primary: #10b981;       /* Emerald / SOC Safe */
  --accent-primary-hover: #059669;
  --accent-primary-glow: rgba(16, 185, 129, 0.2);

  --accent-cyan: #06b6d4;          /* Network / Packet Stream */
  --accent-cyan-glow: rgba(6, 182, 212, 0.2);

  --accent-purple: #a855f7;        /* Pentesting / CEH */
  --accent-amber: #f59e0b;         /* Alerts / Warnings */
  --accent-red: #ef4444;           /* Threat Detection */

  --text-primary: #f8fafc;
  --text-secondary: #94a3b8;
  --text-muted: #64748b;
  --text-accent: #34d399;

  --font-main: 'Plus Jakarta Sans', system-ui, -apple-system, sans-serif;
  --font-mono: 'Fira Code', monospace, Consolas;

  --radius-sm: 8px;
  --radius-md: 14px;
  --radius-lg: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.25);
  --shadow-md: 0 10px 30px -10px rgba(0, 0, 0, 0.5);
  --shadow-glow: 0 0 25px rgba(16, 185, 129, 0.2);
  --shadow-cyan-glow: 0 0 25px rgba(6, 182, 212, 0.2);

  --transition-fast: 0.2s ease;
  --transition-normal: 0.3s cubic-bezier(0.16, 1, 0.3, 1);
  --container-max: 1200px;
}

[data-theme="light"] {
  --bg-base: #f8fafc;
  --bg-surface: #ffffff;
  --bg-card: rgba(255, 255, 255, 0.92);
  --bg-card-hover: rgba(241, 245, 249, 0.98);
  --bg-glass: rgba(255, 255, 255, 0.9);
  --bg-elevated: #f1f5f9;

  --border-subtle: rgba(203, 213, 225, 0.8);
  --border-glow: rgba(16, 185, 129, 0.4);
  --border-highlight: rgba(6, 182, 212, 0.4);

  --accent-primary: #059669;
  --accent-primary-hover: #047857;
  --accent-primary-glow: rgba(5, 150, 105, 0.15);

  --accent-cyan: #0891b2;
  --accent-cyan-glow: rgba(8, 145, 178, 0.15);

  --accent-purple: #7e22ce;
  --accent-amber: #d97706;
  --accent-red: #dc2626;

  --text-primary: #0f172a;
  --text-secondary: #475569;
  --text-muted: #64748b;
  --text-accent: #059669;

  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 12px 30px -10px rgba(0, 0, 0, 0.08);
  --shadow-glow: 0 0 25px rgba(5, 150, 105, 0.15);
  --shadow-cyan-glow: 0 0 25px rgba(8, 145, 178, 0.15);
}

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

html {
  scroll-behavior: smooth;
  scroll-padding-top: 85px;
}

body {
  font-family: var(--font-main);
  background-color: var(--bg-base);
  color: var(--text-primary);
  line-height: 1.65;
  overflow-x: hidden;
  position: relative;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

/* Background Cyber Grid */
.cyber-background-grid {
  position: fixed;
  top: 0;
  left: 0;
  width: 100vw;
  height: 100vh;
  pointer-events: none;
  z-index: 0;
  opacity: 0.45;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(16, 185, 129, 0.12) 0%, transparent 40%),
    radial-gradient(circle at 85% 65%, rgba(6, 182, 212, 0.12) 0%, transparent 45%),
    linear-gradient(to right, rgba(148, 163, 184, 0.05) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(148, 163, 184, 0.05) 1px, transparent 1px);
  background-size: 100% 100%, 100% 100%, 48px 48px, 48px 48px;
}

[data-theme="light"] .cyber-background-grid {
  opacity: 0.65;
  background-image: 
    radial-gradient(circle at 15% 15%, rgba(16, 185, 129, 0.06) 0%, transparent 40%),
    radial-gradient(circle at 85% 65%, rgba(6, 182, 212, 0.06) 0%, transparent 45%),
    linear-gradient(to right, rgba(0, 0, 0, 0.04) 1px, transparent 1px),
    linear-gradient(to bottom, rgba(0, 0, 0, 0.04) 1px, transparent 1px);
}

.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;
}

h1, h2, h3, h4, h5, h6 {
  color: var(--text-primary);
  font-weight: 700;
  line-height: 1.25;
}

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

code, pre, .mono {
  font-family: var(--font-mono);
}

section {
  padding: 5.5rem 0;
  position: relative;
}

.section-header {
  text-align: center;
  margin-bottom: 3.5rem;
  position: relative;
}

.section-tag {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  font-family: var(--font-mono);
  font-size: 0.8rem;
  font-weight: 600;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: var(--accent-primary);
  background: var(--accent-primary-glow);
  border: 1px solid var(--border-glow);
  padding: 0.35rem 1.1rem;
  border-radius: var(--radius-full);
  margin-bottom: 1rem;
}

.section-title {
  font-size: clamp(2rem, 3.5vw, 2.75rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  margin-bottom: 0.75rem;
}

.section-subtitle {
  font-size: 1.05rem;
  color: var(--text-secondary);
  max-width: 650px;
  margin: 0 auto;
}

.gradient-text {
  background: linear-gradient(135deg, var(--accent-primary) 0%, var(--accent-cyan) 50%, var(--accent-purple) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

/* Custom Scrollbar */
::-webkit-scrollbar {
  width: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg-base);
}
::-webkit-scrollbar-thumb {
  background: var(--bg-elevated);
  border-radius: var(--radius-full);
  border: 2px solid var(--bg-base);
}
::-webkit-scrollbar-thumb:hover {
  background: var(--accent-primary);
}