/* ============================================
   Cipher Hayes Books - KDP Tools
   Design System & Styles
   ============================================ */

/* CSS Variables */
:root {
  /* Colors - Dark Theme */
  --color-bg-primary: #0a0a0f;
  --color-bg-secondary: #12121a;
  --color-bg-tertiary: #1a1a24;
  --color-bg-card: #16161f;
  --color-bg-hover: #1e1e2a;

  /* Accent Colors */
  --color-accent-primary: #6366f1;
  --color-accent-secondary: #8b5cf6;
  --color-accent-gradient: linear-gradient(135deg, #6366f1 0%, #8b5cf6 100%);

  /* Text Colors */
  --color-text-primary: #f8fafc;
  --color-text-secondary: #94a3b8;
  --color-text-muted: #64748b;

  /* Status Colors */
  --color-success: #10b981;
  --color-warning: #f59e0b;
  --color-error: #ef4444;

  /* Border */
  --color-border: #2a2a3a;
  --color-border-hover: #3a3a4a;

  /* Spacing */
  --spacing-xs: 0.25rem;
  --spacing-sm: 0.5rem;
  --spacing-md: 1rem;
  --spacing-lg: 1.5rem;
  --spacing-xl: 2rem;
  --spacing-2xl: 3rem;

  /* Typography */
  --font-family: 'Inter', -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
  --font-size-xs: 0.75rem;
  --font-size-sm: 0.875rem;
  --font-size-md: 1rem;
  --font-size-lg: 1.125rem;
  --font-size-xl: 1.25rem;
  --font-size-2xl: 1.5rem;
  --font-size-3xl: 2rem;
  --font-size-4xl: 2.5rem;

  /* Border Radius */
  --radius-sm: 0.375rem;
  --radius-md: 0.5rem;
  --radius-lg: 0.75rem;
  --radius-xl: 1rem;

  /* Shadows */
  --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
  --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.1);
  --shadow-lg: 0 10px 15px -3px rgb(0 0 0 / 0.1);
  --shadow-glow: 0 0 20px rgba(99, 102, 241, 0.3);

  /* Transitions */
  --transition-fast: 150ms ease;
  --transition-normal: 250ms ease;
  --transition-slow: 350ms ease;
}

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

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-family);
  font-size: var(--font-size-md);
  line-height: 1.6;
  color: var(--color-text-primary);
  background-color: var(--color-bg-primary);
  min-height: 100vh;
}

/* Typography */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-weight: 600;
  line-height: 1.3;
  color: var(--color-text-primary);
}

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);
}

p {
  color: var(--color-text-secondary);
  margin-bottom: var(--spacing-md);
}

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

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

/* Layout */
.container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 0 var(--spacing-lg);
}

.section {
  padding: var(--spacing-2xl) 0;
}

/* Header */
.header {
  background: var(--color-bg-secondary);
  border-bottom: 1px solid var(--color-border);
  position: sticky;
  top: 0;
  z-index: 100;
}

.header-content {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding: var(--spacing-md) 0;
}

.logo {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-xl);
  font-weight: 700;
  color: var(--color-text-primary);
}

.logo-icon {
  width: 32px;
  height: 32px;
  background: var(--color-accent-gradient);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.logo-icon svg {
  width: 20px;
  height: 20px;
  color: white;
}

/* Navigation */
.nav {
  display: flex;
  align-items: center;
  gap: var(--spacing-lg);
}

.nav-link {
  display: flex;
  align-items: center;
  gap: var(--spacing-xs);
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  padding: var(--spacing-sm) var(--spacing-md);
  border-radius: var(--radius-md);
  transition: all var(--transition-fast);
}

.nav-link:hover {
  color: var(--color-text-primary);
  background: var(--color-bg-hover);
}

.nav-link.active {
  color: var(--color-accent-primary);
  background: rgba(99, 102, 241, 0.1);
}

.nav-link svg {
  width: 18px;
  height: 18px;
}

/* Mobile Menu */
.mobile-menu-btn {
  display: none;
  padding: var(--spacing-sm);
  background: transparent;
  border: none;
  color: var(--color-text-primary);
  cursor: pointer;
}

.mobile-menu-btn svg {
  width: 24px;
  height: 24px;
}

@media (max-width: 768px) {
  .nav {
    display: none;
    position: absolute;
    top: 100%;
    left: 0;
    right: 0;
    flex-direction: column;
    background: var(--color-bg-secondary);
    border-bottom: 1px solid var(--color-border);
    padding: var(--spacing-md);
    gap: var(--spacing-sm);
  }

  .nav.active {
    display: flex;
  }

  .nav-link {
    width: 100%;
    justify-content: flex-start;
  }

  .mobile-menu-btn {
    display: block;
  }
}

/* Hero Section */
.hero {
  text-align: center;
  padding: var(--spacing-2xl) 0;
  background: linear-gradient(180deg, var(--color-bg-secondary) 0%, var(--color-bg-primary) 100%);
}

.hero h1 {
  margin-bottom: var(--spacing-md);
}

.hero-highlight {
  background: var(--color-accent-gradient);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.hero-description {
  font-size: var(--font-size-lg);
  max-width: 600px;
  margin: 0 auto var(--spacing-xl);
}

/* Tool Cards Grid */
.tools-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.tool-card {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
  text-decoration: none;
  transition: all var(--transition-normal);
  display: flex;
  flex-direction: column;
  gap: var(--spacing-md);
}

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

.tool-icon {
  width: 48px;
  height: 48px;
  background: var(--color-accent-gradient);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
}

.tool-icon svg {
  width: 24px;
  height: 24px;
  color: white;
}

.tool-card h3 {
  font-size: var(--font-size-xl);
  color: var(--color-text-primary);
}

.tool-card p {
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
  margin: 0;
  flex-grow: 1;
}

.tool-card-footer {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: var(--color-accent-primary);
  font-size: var(--font-size-sm);
  font-weight: 500;
  margin-top: var(--spacing-sm);
}

.tool-card-footer svg {
  width: 16px;
  height: 16px;
}

/* Calculator Page */
.calculator-page {
  padding: var(--spacing-xl) 0;
}

.calculator-header {
  margin-bottom: var(--spacing-xl);
}

.calculator-header h1 {
  margin-bottom: var(--spacing-sm);
}

.breadcrumb {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-sm);
  color: var(--color-text-muted);
  margin-bottom: var(--spacing-md);
}

.breadcrumb a {
  color: var(--color-text-muted);
}

.breadcrumb a:hover {
  color: var(--color-accent-primary);
}

.breadcrumb svg {
  width: 14px;
  height: 14px;
}

/* Calculator Form */
.calculator-container {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: var(--spacing-xl);
}

@media (max-width: 900px) {
  .calculator-container {
    grid-template-columns: 1fr;
  }
}

.calculator-form {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
}

.form-group {
  margin-bottom: var(--spacing-lg);
}

.form-label {
  display: block;
  font-size: var(--font-size-sm);
  font-weight: 500;
  color: var(--color-text-primary);
  margin-bottom: var(--spacing-sm);
}

.form-label-hint {
  font-weight: 400;
  color: var(--color-text-muted);
  margin-left: var(--spacing-sm);
}

.form-input,
.form-select {
  width: 100%;
  padding: var(--spacing-md);
  background: var(--color-bg-tertiary);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  color: var(--color-text-primary);
  font-size: var(--font-size-md);
  font-family: inherit;
  transition: all var(--transition-fast);
}

.form-input:focus,
.form-select:focus {
  outline: none;
  border-color: var(--color-accent-primary);
  box-shadow: 0 0 0 3px rgba(99, 102, 241, 0.2);
}

.form-input::placeholder {
  color: var(--color-text-muted);
}

.form-select {
  cursor: pointer;
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='24' height='24' viewBox='0 0 24 24' fill='none' stroke='%2394a3b8' stroke-width='2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='m6 9 6 6 6-6'/%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right var(--spacing-md) center;
  background-size: 20px;
  padding-right: calc(var(--spacing-md) * 3);
}

/* Button */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: var(--spacing-sm);
  padding: var(--spacing-md) var(--spacing-xl);
  font-size: var(--font-size-md);
  font-weight: 600;
  border-radius: var(--radius-md);
  border: none;
  cursor: pointer;
  transition: all var(--transition-fast);
  font-family: inherit;
}

.btn-primary {
  background: var(--color-accent-gradient);
  color: white;
}

.btn-primary:hover {
  opacity: 0.9;
  box-shadow: var(--shadow-glow);
}

.btn-secondary {
  background: var(--color-bg-tertiary);
  color: var(--color-text-primary);
  border: 1px solid var(--color-border);
}

.btn-secondary:hover {
  background: var(--color-bg-hover);
  border-color: var(--color-border-hover);
}

.btn-block {
  width: 100%;
}

.btn svg {
  width: 18px;
  height: 18px;
}

/* Results Panel */
.results-panel {
  background: var(--color-bg-card);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--spacing-xl);
}

.results-title {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-lg);
  margin-bottom: var(--spacing-lg);
}

.results-title svg {
  width: 20px;
  height: 20px;
  color: var(--color-accent-primary);
}

.result-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--spacing-md) 0;
  border-bottom: 1px solid var(--color-border);
}

.result-item:last-child {
  border-bottom: none;
}

.result-label {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  color: var(--color-text-secondary);
  font-size: var(--font-size-sm);
}

.result-label svg {
  width: 16px;
  height: 16px;
}

.result-value {
  font-size: var(--font-size-xl);
  font-weight: 600;
  color: var(--color-text-primary);
}

.result-value.highlight {
  color: var(--color-success);
}

.result-value.warning {
  color: var(--color-warning);
}

.result-value.error {
  color: var(--color-error);
}

/* Empty Results */
.results-empty {
  text-align: center;
  padding: var(--spacing-2xl);
  color: var(--color-text-muted);
}

.results-empty svg {
  width: 48px;
  height: 48px;
  margin-bottom: var(--spacing-md);
  opacity: 0.5;
}

/* Ad Container - Hidden until real ads are added */
/* When you add AdSense code, remove 'display: none' or add 'has-ad' class */
.ad-container {
  /* Hidden by default - no visible placeholder */
  display: none;
  background: transparent;
  border-radius: var(--radius-md);
  text-align: center;
  margin: var(--spacing-xl) 0;
}

/* Show container when it has real ad content */
.ad-container:has(ins),
.ad-container:has(iframe),
.ad-container.has-ad {
  display: block;
}

.ad-container.horizontal {
  min-height: 90px;
}

.ad-container.sidebar {
  min-height: 250px;
}

/* Footer */
.footer {
  background: var(--color-bg-secondary);
  border-top: 1px solid var(--color-border);
  padding: var(--spacing-xl) 0;
  margin-top: var(--spacing-2xl);
}

.footer-content {
  display: flex;
  justify-content: space-between;
  align-items: center;
  flex-wrap: wrap;
  gap: var(--spacing-md);
}

.footer-text {
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

.footer-links {
  display: flex;
  gap: var(--spacing-lg);
}

.footer-links a {
  color: var(--color-text-muted);
  font-size: var(--font-size-sm);
}

.footer-links a:hover {
  color: var(--color-accent-primary);
}

/* Utilities */
.text-center {
  text-align: center;
}

.text-muted {
  color: var(--color-text-muted);
}

.mt-md {
  margin-top: var(--spacing-md);
}

.mt-lg {
  margin-top: var(--spacing-lg);
}

.mb-md {
  margin-bottom: var(--spacing-md);
}

.mb-lg {
  margin-bottom: var(--spacing-lg);
}

/* Info Box */
.info-box {
  display: flex;
  gap: var(--spacing-md);
  padding: var(--spacing-lg);
  background: rgba(99, 102, 241, 0.1);
  border: 1px solid rgba(99, 102, 241, 0.3);
  border-radius: var(--radius-md);
  margin-top: var(--spacing-lg);
}

.info-box svg {
  width: 20px;
  height: 20px;
  color: var(--color-accent-primary);
  flex-shrink: 0;
}

.info-box-content {
  font-size: var(--font-size-sm);
  color: var(--color-text-secondary);
}

.info-box-content strong {
  color: var(--color-text-primary);
}

/* Section Title */
.section-title {
  display: flex;
  align-items: center;
  gap: var(--spacing-sm);
  font-size: var(--font-size-2xl);
  margin-bottom: var(--spacing-lg);
}

.section-title svg {
  width: 24px;
  height: 24px;
  color: var(--color-accent-primary);
}

/* Features List */
.features-list {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
  gap: var(--spacing-lg);
  margin-top: var(--spacing-xl);
}

.feature-item {
  display: flex;
  gap: var(--spacing-md);
}

.feature-icon {
  width: 40px;
  height: 40px;
  background: rgba(99, 102, 241, 0.1);
  border-radius: var(--radius-md);
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}

.feature-icon svg {
  width: 20px;
  height: 20px;
  color: var(--color-accent-primary);
}

.feature-content h4 {
  font-size: var(--font-size-md);
  margin-bottom: var(--spacing-xs);
}

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