/* 
 * ----------------------------------------------------------------------------
 * 1. VARIABLES
 * ----------------------------------------------------------------------------
 */
:root {
  /* Colors: Soft Blue, Medium Gray, Teal Accents */
  --color-primary: #3d5a80;       /* Professional Soft Blue */
  --color-primary-dark: #293241;  /* Darker Navy for contrast */
  --color-accent: #2a9d8f;        /* Teal Accent */
  --color-accent-hover: #21867a;
  
  --color-text: #2d3748;          /* Dark Gray for readability */
  --color-text-light: #718096;    /* Medium Gray for metadata */
  --color-background: #f7fafc;    /* Very light gray/blue tint background */
  --color-surface: #ffffff;       /* White surface */
  --color-border: #e2e8f0;

  --color-success: #38a169;
  --color-warning: #ecc94b;
  --color-danger: #e53e3e;

  /* Typography */
  --font-family-base: 'Inter', system-ui, -apple-system, sans-serif;
  --font-family-heading: 'Inter', system-ui, sans-serif;
  
  --font-size-sm: 0.875rem;
  --font-size-base: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 1.875rem;
  --font-size-4xl: 2.25rem;

  --line-height-base: 1.6;
  --line-height-heading: 1.2;

  /* Spacing Scale */
  --space-1: 0.25rem;  /* 4px */
  --space-2: 0.5rem;   /* 8px */
  --space-3: 0.75rem;  /* 12px */
  --space-4: 1rem;     /* 16px */
  --space-6: 1.5rem;   /* 24px */
  --space-8: 2rem;     /* 32px */
  --space-12: 3rem;    /* 48px */
  --space-16: 4rem;    /* 64px */
  --space-24: 6rem;    /* 96px */

  /* UI Helpers */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.1), 0 2px 4px -1px rgba(0, 0, 0, 0.06);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1), 0 4px 6px -2px rgba(0, 0, 0, 0.05);

  --transition-base: 200ms ease-in-out;
}

/* 
 * ----------------------------------------------------------------------------
 * 2. RESET & NORMALIZE
 * ----------------------------------------------------------------------------
 */
*, *::before, *::after {
  box-sizing: border-box;
}

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

body, h1, h2, h3, h4, h5, h6, p, figure, blockquote, dl, dd {
  margin: 0;
}

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

input, button, textarea, select {
  font: inherit;
}

/* 
 * ----------------------------------------------------------------------------
 * 3. BASE STYLES
 * ----------------------------------------------------------------------------
 */
body {
  font-family: var(--font-family-base);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text);
  background-color: var(--color-background);
  -webkit-font-smoothing: antialiased;
}

h1, h2, h3, h4, h5, h6 {
  font-family: var(--font-family-heading);
  font-weight: 700;
  line-height: var(--line-height-heading);
  color: var(--color-primary-dark);
  margin-bottom: var(--space-4);
}

h1 { font-size: var(--font-size-4xl); }
h2 { font-size: var(--font-size-3xl); }
h3 { font-size: var(--font-size-2xl); }
h4 { font-size: var(--font-size-xl); }
h5 { font-size: var(--font-size-lg); }

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

a {
  color: var(--color-primary);
  text-decoration: none;
  transition: color var(--transition-base);
}

a:hover {
  color: var(--color-accent);
  text-decoration: underline;
}

/* 
 * ----------------------------------------------------------------------------
 * 4. UTILITIES
 * ----------------------------------------------------------------------------
 */
.container {
  width: 100%;
  max-width: 1200px;
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--space-4);
  padding-right: var(--space-4);
}

.flex {
  display: flex;
}

.grid {
  display: grid;
}

.items-center { align-items: center; }
.justify-between { justify-content: space-between; }
.gap-4 { gap: var(--space-4); }
.gap-6 { gap: var(--space-6); }
.gap-8 { gap: var(--space-8); }

.text-center { text-align: center; }
.text-muted { color: var(--color-text-light); }
.mt-4 { margin-top: var(--space-4); }
.mb-4 { margin-bottom: var(--space-4); }

.text-white {
  color: #fff;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  padding: 0;
  margin: -1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
}

/* 
 * ----------------------------------------------------------------------------
 * 5. COMPONENTS
 * ----------------------------------------------------------------------------
 */

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-3) var(--space-6);
  font-weight: 600;
  font-size: var(--font-size-base);
  border-radius: var(--radius-md);
  border: 2px solid transparent;
  cursor: pointer;
  transition: all var(--transition-base);
  text-decoration: none;
}

.btn-primary {
  background-color: var(--color-primary);
  color: #fff;
}

.btn-primary:hover,
.btn-primary:focus {
  background-color: var(--color-primary-dark);
  color: #fff;
  text-decoration: none;
  transform: translateY(-1px);
  box-shadow: var(--shadow-md);
}

.btn-accent {
  background-color: var(--color-accent);
  color: #fff;
}

.btn-accent:hover,
.btn-accent:focus {
  background-color: var(--color-accent-hover);
  color: #fff;
  text-decoration: none;
}

.btn:disabled {
  opacity: 0.65;
  cursor: not-allowed;
  transform: none;
}

/* Inputs */
.form-control {
  display: block;
  width: 100%;
  padding: var(--space-3) var(--space-4);
  font-size: var(--font-size-base);
  line-height: var(--line-height-base);
  color: var(--color-text);
  background-color: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: border-color var(--transition-base), box-shadow var(--transition-base);
}

.form-control:focus {
  outline: 0;
  border-color: var(--color-accent);
  box-shadow: 0 0 0 3px rgba(42, 157, 143, 0.2);
}

/* Cards */
.card {
  background-color: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  padding: var(--space-6);
  border: 1px solid var(--color-border);
  transition: box-shadow var(--transition-base);
}

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

/* 
 * ----------------------------------------------------------------------------
 * 6. ACCESSIBILITY
 * ----------------------------------------------------------------------------
 */
:focus-visible {
  outline: 2px solid var(--color-accent);
  outline-offset: 2px;
}

@media (prefers-reduced-motion: reduce) {
  html {
    scroll-behavior: auto;
  }
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
    scroll-behavior: auto !important;
  }
}