/* ============================================================
   GST COMPLIANCE PRO - MASTER DESIGN SYSTEM V3
   Modern Bharat Fintech Aesthetic
   Built for: mygstindia.in relaunch
   Version: 3.0 Production (February 2026)
   ============================================================ */

/* ============================================================
   DESIGN TOKENS - THE SOURCE OF TRUTH
   ============================================================ */

:root {
  /* Brand Colors - Modern Bharat Fintech */
  --indigo-primary: #4f46e5;
  --indigo-hover: #4338ca;
  --indigo-light: #818cf8;
  --indigo-bg: #eef2ff;
  
  --green-success: #10b981;
  --green-hover: #059669;
  --green-light: #34d399;
  --green-bg: #d1fae5;
  
  --slate-900: #0f172a;
  --slate-800: #1e293b;
  --slate-700: #334155;
  --slate-600: #475569;
  --slate-500: #64748b;
  --slate-400: #94a3b8;
  --slate-300: #cbd5e1;
  --slate-200: #e2e8f0;
  --slate-100: #f1f5f9;
  --slate-50: #f8fafc;
  
  /* Semantic Colors */
  --color-background: #f8fafc;
  --color-surface: #ffffff;
  --color-primary: var(--indigo-primary);
  --color-success: var(--green-success);
  --color-text: var(--slate-900);
  --color-text-secondary: var(--slate-600);
  --color-text-muted: var(--slate-500);
  --color-border: var(--slate-200);
  --color-border-light: var(--slate-100);
  
  /* Typography - 3 Weights Only */
  --font-primary: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --font-display: 'Poppins', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  --weight-normal: 400;
  --weight-semibold: 600;
  --weight-bold: 700;
  
  /* Type Scale - Fluid & Responsive */
  --text-xs: clamp(0.75rem, 0.7rem + 0.2vw, 0.8125rem);
  --text-sm: clamp(0.875rem, 0.825rem + 0.25vw, 0.9375rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.0625rem);
  --text-lg: clamp(1.125rem, 1.05rem + 0.375vw, 1.25rem);
  --text-xl: clamp(1.25rem, 1.15rem + 0.5vw, 1.5rem);
  --text-2xl: clamp(1.5rem, 1.35rem + 0.75vw, 1.875rem);
  --text-3xl: clamp(1.875rem, 1.65rem + 1.125vw, 2.25rem);
  --text-4xl: clamp(2.25rem, 1.95rem + 1.5vw, 3rem);
  
  /* Spacing System - 4px Base Unit */
  --space-1: 0.25rem;   /* 4px */
  --space-2: 0.5rem;    /* 8px */
  --space-3: 0.75rem;   /* 12px */
  --space-4: 1rem;      /* 16px */
  --space-5: 1.25rem;   /* 20px */
  --space-6: 1.5rem;    /* 24px */
  --space-8: 2rem;      /* 32px */
  --space-10: 2.5rem;   /* 40px */
  --space-12: 3rem;     /* 48px */
  --space-16: 4rem;     /* 64px */
  --space-20: 5rem;     /* 80px */
  
  /* Touch Targets */
  --touch-min: 48px;
  
  /* Layout */
  --container-max: 1280px;
  --container-padding: var(--space-6);
  
  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;
  --radius-2xl: 1.5rem;
  --radius-full: 9999px;
  
  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1);
  
  /* Transitions */
  --transition-fast: 150ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-base: 250ms cubic-bezier(0.4, 0, 0.2, 1);
  --transition-slow: 350ms cubic-bezier(0.4, 0, 0.2, 1);
}

/* ============================================================
   SCOPED RESET - NO NUCLEAR !IMPORTANT
   ============================================================ */

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

html {
  font-size: 16px;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  text-rendering: optimizeLegibility;
  scroll-behavior: smooth;
}

body {
  margin: 0;
  padding: 0;
  font-family: var(--font-primary);
  font-size: var(--text-base);
  font-weight: var(--weight-normal);
  line-height: 1.6;
  color: var(--color-text);
  background: var(--color-background);
  min-height: 100vh;
}

/* Reset margins on key elements */
h1, h2, h3, h4, h5, h6,
p, ul, ol, dl,
blockquote, pre,
figure, hr {
  margin: 0;
  padding: 0;
}

/* Lists */
ul, ol {
  list-style: none;
}

/* Links */
a {
  color: inherit;
  text-decoration: none;
}

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

/* Forms */
button, input, textarea, select {
  font: inherit;
  color: inherit;
}

/* ============================================================
   TYPOGRAPHY SYSTEM
   ============================================================ */

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-display);
  font-weight: var(--weight-bold);
  line-height: 1.2;
  letter-spacing: -0.02em;
  color: var(--slate-900);
}

h1 {
  font-size: var(--text-4xl);
  margin-bottom: var(--space-6);
}

h2 {
  font-size: var(--text-3xl);
  margin-bottom: var(--space-5);
}

h3 {
  font-size: var(--text-2xl);
  margin-bottom: var(--space-4);
}

h4 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-3);
}

p {
  margin-bottom: var(--space-4);
  color: var(--color-text-secondary);
  line-height: 1.7;
}

/* Gradient Text */
.text-gradient {
  background: linear-gradient(135deg, var(--indigo-primary), var(--indigo-light));
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

/* ============================================================
   LAYOUT CONTAINERS
   ============================================================ */

.container {
  max-width: var(--container-max);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
  width: 100%;
}

.container-narrow {
  max-width: 900px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--container-padding);
  padding-right: var(--container-padding);
}

/* ============================================================
   COMPONENT: BUTTONS
   ============================================================ */

.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--space-2);
  min-height: var(--touch-min);
  padding: 0 var(--space-6);
  font-size: var(--text-base);
  font-weight: var(--weight-semibold);
  font-family: var(--font-primary);
  color: white;
  background: linear-gradient(135deg, var(--indigo-primary) 0%, var(--indigo-hover) 100%);
  border: none;
  border-radius: var(--radius-lg);
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
  white-space: nowrap;
}

.btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.btn:active {
  transform: translateY(0);
}

.btn-secondary {
  background: var(--slate-100);
  color: var(--slate-900);
}

.btn-secondary:hover {
  background: var(--slate-200);
}

.btn-success {
  background: linear-gradient(135deg, var(--green-success) 0%, var(--green-hover) 100%);
}

.btn-sm {
  min-height: 40px;
  padding: 0 var(--space-4);
  font-size: var(--text-sm);
}

/* ============================================================
   COMPONENT: CARDS
   ============================================================ */

.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-2xl);
  padding: var(--space-8);
  box-shadow: var(--shadow-sm);
  transition: all var(--transition-base);
}

.card:hover {
  box-shadow: var(--shadow-md);
}

.card-body {
  padding: 0;
}

/* Tool Card - Clickable */
.tool-card {
  display: block;
  background: var(--color-surface);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-2xl);
  padding: var(--space-6);
  text-decoration: none;
  transition: all var(--transition-base);
  position: relative;
  overflow: hidden;
}

.tool-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--indigo-primary), var(--green-success));
  transform: scaleX(0);
  transition: transform var(--transition-base);
}

.tool-card:hover::before {
  transform: scaleX(1);
}

.tool-card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-xl);
  border-color: var(--indigo-primary);
}

.tool-icon {
  font-size: 3rem;
  margin-bottom: var(--space-3);
  display: block;
}

/* ============================================================
   COMPONENT: FORMS
   ============================================================ */

.form-group {
  margin-bottom: var(--space-5);
}

.form-group label {
  display: block;
  font-size: var(--text-sm);
  font-weight: var(--weight-semibold);
  color: var(--slate-700);
  margin-bottom: var(--space-2);
}

input[type="text"],
input[type="email"],
input[type="number"],
input[type="tel"],
input[type="search"],
select,
textarea {
  width: 100%;
  min-height: var(--touch-min);
  padding: var(--space-3) var(--space-4);
  font-size: var(--text-base);
  font-family: var(--font-primary);
  color: var(--color-text);
  background: var(--color-surface);
  border: 2px solid var(--color-border);
  border-radius: var(--radius-lg);
  transition: all var(--transition-base);
  outline: none;
}

input:focus,
select:focus,
textarea:focus {
  border-color: var(--indigo-primary);
  box-shadow: 0 0 0 4px var(--indigo-bg);
}

input::placeholder,
textarea::placeholder {
  color: var(--color-text-muted);
}

/* ============================================================
   COMPONENT: INFO BOXES
   ============================================================ */

.info-box {
  display: flex;
  gap: var(--space-4);
  padding: var(--space-5);
  border-radius: var(--radius-xl);
  border-left: 4px solid;
  margin: var(--space-6) 0;
}

.info-box-icon {
  font-size: var(--text-2xl);
  flex-shrink: 0;
}

.info-box-content {
  flex: 1;
}

.info-box-content h4 {
  margin: 0 0 var(--space-2);
  font-size: var(--text-lg);
}

.info-box-content p {
  margin: 0;
  font-size: var(--text-sm);
}

.info-box.blue {
  background: var(--indigo-bg);
  border-color: var(--indigo-primary);
}

.info-box.blue .info-box-icon {
  color: var(--indigo-primary);
}

.info-box.green {
  background: var(--green-bg);
  border-color: var(--green-success);
}

.info-box.green .info-box-icon {
  color: var(--green-success);
}

/* ============================================================
   COMPONENT: NAVBAR
   ============================================================ */

.navbar {
  background: rgba(255, 255, 255, 0.8);
  backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar-container {
  max-width: var(--container-max);
  margin: 0 auto;
  padding: var(--space-4) var(--container-padding);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-8);
}

.nav-logo {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  font-size: var(--text-xl);
  font-weight: var(--weight-bold);
  font-family: var(--font-display);
  color: var(--slate-900);
  text-decoration: none;
}

.logo-mark {
  width: 40px;
  height: 40px;
  background: linear-gradient(135deg, var(--indigo-primary), var(--indigo-light));
  border-radius: var(--radius-lg);
  display: flex;
  align-items: center;
  justify-content: center;
  color: white;
  font-weight: var(--weight-bold);
  font-size: var(--text-lg);
}

.nav-links {
  display: flex;
  gap: var(--space-6);
  margin: 0;
  padding: 0;
  list-style: none;
}

.nav-links a {
  min-height: var(--touch-min);
  display: flex;
  align-items: center;
  padding: 0 var(--space-3);
  color: var(--slate-700);
  font-weight: var(--weight-semibold);
  font-size: var(--text-sm);
  border-radius: var(--radius-md);
  transition: all var(--transition-base);
}

.nav-links a:hover,
.nav-links a.active {
  color: var(--indigo-primary);
  background: var(--indigo-bg);
}

.mobile-menu-toggle {
  display: none;
  flex-direction: column;
  gap: 4px;
  background: none;
  border: none;
  cursor: pointer;
  padding: var(--space-2);
  min-height: var(--touch-min);
  min-width: var(--touch-min);
}

.mobile-menu-toggle span {
  width: 24px;
  height: 2px;
  background: var(--slate-900);
  border-radius: var(--radius-full);
  transition: all var(--transition-base);
}

/* ============================================================
   COMPONENT: FOOTER
   ============================================================ */

.footer {
  background: var(--slate-900);
  color: var(--slate-400);
  padding: var(--space-16) var(--container-padding) var(--space-8);
  margin-top: var(--space-20);
}

.footer-grid {
  max-width: var(--container-max);
  margin: 0 auto var(--space-12);
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: var(--space-8);
}

.footer h4 {
  color: white;
  font-size: var(--text-lg);
  margin-bottom: var(--space-4);
}

.footer ul {
  padding: 0;
  margin: 0;
}

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

.footer a {
  color: var(--slate-400);
  transition: color var(--transition-base);
}

.footer a:hover {
  color: var(--indigo-light);
}

.footer-bottom {
  max-width: var(--container-max);
  margin: 0 auto;
  padding-top: var(--space-8);
  border-top: 1px solid var(--slate-700);
  text-align: center;
  font-size: var(--text-sm);
  color: var(--slate-500);
}

/* ============================================================
   UTILITY CLASSES
   ============================================================ */

.text-center {
  text-align: center;
}

.text-left {
  text-align: left;
}

.mt-8 {
  margin-top: var(--space-8);
}

.mb-8 {
  margin-bottom: var(--space-8);
}

.hidden {
  display: none;
}

/* ============================================================
   SCROLLBAR
   ============================================================ */

::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}

::-webkit-scrollbar-track {
  background: var(--slate-100);
}

::-webkit-scrollbar-thumb {
  background: var(--slate-300);
  border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--indigo-primary);
}

/* ============================================================
   PHASE 2: ENTERPRISE ENHANCEMENTS
   ============================================================ */

/* Ash's Enterprise Scoped Reset */
.tool-engine-centered {
  max-width: 900px;
  margin: var(--space-12) auto;
  display: flex;
  flex-direction: column;
  align-items: center;
  text-align: center;
}

/* Success Glow for Calculator Results */
.result-display-glow {
  background: linear-gradient(135deg, var(--indigo-bg) 0%, #ffffff 100%);
  border: 3px solid var(--indigo-primary);
  box-shadow: 0 0 30px rgba(79, 70, 229, 0.2);
  padding: var(--space-8);
  border-radius: var(--radius-2xl);
  animation: resultEntrance 0.3s ease-out;
}

@keyframes resultEntrance {
  from { 
    opacity: 0; 
    transform: scale(0.95); 
  }
  to { 
    opacity: 1; 
    transform: scale(1); 
  }
}

/* Pulse animation for special elements */
@keyframes pulseGlow {
  0%, 100% {
    box-shadow: 0 0 20px rgba(79, 70, 229, 0.3);
  }
  50% {
    box-shadow: 0 0 40px rgba(79, 70, 229, 0.6);
  }
}

.pulse-glow {
  animation: pulseGlow 2s ease-in-out infinite;
}

/* Reading Progress Bar */
.reading-progress-bar {
  position: fixed;
  top: 0;
  left: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--indigo-primary), var(--green-success));
  z-index: 1001;
  width: 0%;
  transition: width 0.1s ease-out;
}

/* ============================================================
   MOBILE BREAKPOINTS
   ============================================================ */

/* Mobile Edge Protection */
@media (max-width: 480px) {
  body {
    padding-left: 2px;
    padding-right: 2px;
  }
}

@media (max-width: 768px) {
  .mobile-menu-toggle {
    display: flex;
  }
  
  .nav-links {
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    background: white;
    flex-direction: column;
    padding: var(--space-4);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-lg);
    display: none;
  }
  
  .nav-links.active {
    display: flex;
  }
}