/* ============================================
   Hands & Code Studio - Design System
   ============================================ */

/* ============================================
   1. CSS Reset & Base Styles
   ============================================ */

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

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

body {
  font-family: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
  line-height: 1.6;
  color: var(--color-craft-black);
  background-color: var(--color-white);
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  transition: background-color 0.3s ease, color 0.3s ease;
}

/* Smooth transitions for theme changes */
*,
*::before,
*::after {
  transition-property: background-color, border-color, color, fill, stroke;
  transition-duration: 0.3s;
  transition-timing-function: ease;
}

/* Respect user's motion preferences */
@media (prefers-reduced-motion: reduce) {

  *,
  *::before,
  *::after {
    transition: none !important;
    animation: none !important;
  }
}

/* ============================================
   2. Design Tokens - Color System
   ============================================ */

:root {
  /* Primary Colors */
  --color-craft-black: #1A1A1A;
  --color-digital-blue: #2A6DF4;

  /* Secondary Colors */
  --color-warm-wood: #C7A279;
  --color-soft-grey: #E5E5E5;
  --color-electric-mint: #64FFD6;
  --color-hands-green: #4CAF50;
  /* Legacy support */
  --color-hands-primary: #2E7D32;
  --color-hands-secondary: #4CAF50;
  --color-hands-accent: #69F0AE;
  --color-hands-dark: #2E7D32;
  /* Legacy support */
  --color-hands-light: #69F0AE;
  /* Legacy support */
  --color-code-primary: #3366ff;
  --color-code-secondary: #5588ff;
  --color-code-accent: #77aaff;
  --color-code-dark: #3366ff;
  --color-code-light: #bbeeff;
  --color-code-beige: #E6D6A2;
  --color-code-brown: #CBB684;
  --color-about-primary: #84629E;
  --color-about-secondary: #A18AC1;
  --color-about-light: #D8BAD4;
  --color-about-accent: #CD9BC3;
  --color-about-pink-light: #F3CDE6;
  --color-about-pink-medium: #CD9BC3;
  --color-hands-accent: #7DB360;
  --color-notes-primary: #00897B;
  --color-notes-secondary: #26A69A;
  --color-notes-secondary: #26A69A;
  --color-notes-accent: #64FFD6;

  /* Brand Colors */
  --color-youtube-red: #FF0000;
  --color-youtube-black: #0F0F0F;

  /* Neutral Colors */
  --color-white: #FFFFFF;
  --color-grey-100: #F5F5F5;
  --color-grey-200: #E0E0E0;
  --color-grey-300: #BDBDBD;
  --color-grey-700: #616161;
  --color-grey-900: #212121;

  /* Semantic Colors */
  --color-text-primary: var(--color-craft-black);
  --color-text-secondary: var(--color-grey-700);
  --color-background: var(--color-white);
  --color-background-alt: var(--color-grey-100);
  --color-accent: var(--color-digital-blue);
  --color-accent-secondary: var(--color-electric-mint);
}

/* ============================================
   Dark Mode Color System
   ============================================ */

[data-theme="dark"] {
  /* Primary Colors - Adjusted for dark backgrounds */
  --color-craft-black: #E8E8E8;
  --color-digital-blue: #5B9FFF;

  /* Secondary Colors - Brightened for visibility */
  --color-warm-wood: #D4B896;
  --color-soft-grey: #2A2A2A;
  --color-electric-mint: #7DFFE0;
  --color-hands-green: #4CAF50;
  --color-hands-primary: #2E7D32;
  --color-hands-secondary: #4CAF50;
  --color-hands-accent: #69F0AE;
  --color-hands-dark: #2E7D32;
  --color-hands-light: #69F0AE;
  --color-code-primary: #3366ff;
  --color-code-secondary: #5588ff;
  --color-code-accent: #77aaff;
  --color-code-dark: #3366ff;
  --color-code-light: #bbeeff;
  /* Legacy support */
  --color-code-beige: #E6D6A2;
  --color-code-brown: #CBB684;
  --color-about-primary: #84629E;
  --color-about-secondary: #A18AC1;
  --color-about-light: #D8BAD4;
  --color-about-accent: #CD9BC3;
  --color-about-pink-light: #F3CDE6;
  --color-about-pink-medium: #CD9BC3;
  --color-hands-accent: #7DB360;

  /* Neutral Colors - Dark theme palette */
  --color-white: #121212;
  --color-grey-100: #1E1E1E;
  --color-grey-200: #2A2A2A;
  --color-grey-300: #404040;
  --color-grey-700: #A0A0A0;
  --color-grey-900: #E8E8E8;

  /* Semantic Colors - Dark mode */
  --color-text-primary: #E8E8E8;
  --color-text-secondary: #A0A0A0;
  --color-text-tertiary: #707070;
  --color-background: #121212;
  --color-background-alt: #1E1E1E;
  --color-background-elevated: #2A2A2A;
  --color-accent: var(--color-digital-blue);
  --color-accent-secondary: var(--color-electric-mint);

  /* Borders & Dividers */
  --color-border: #2A2A2A;
  --color-border-subtle: #1E1E1E;

  /* Shadows - Darker for dark mode */
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.5);
  --shadow-md: 0 4px 6px -1px rgba(0, 0, 0, 0.6);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.7);
  --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.8);
}

/* ============================================
   3. Typography System
   ============================================ */

/* Google Fonts Import */
@import url('https://fonts.googleapis.com/css2?family=Space+Grotesk:wght@400;500;600;700&display=swap');
@import url('https://cdn.jsdelivr.net/gh/orioncactus/pretendard@v1.3.9/dist/web/static/pretendard.min.css');

:root {
  /* Font Families */
  --font-heading: 'Space Grotesk', -apple-system, BlinkMacSystemFont, sans-serif;
  --font-body: 'Pretendard', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;

  /* Font Sizes */
  --font-size-xs: 0.75rem;
  /* 12px */
  --font-size-sm: 0.875rem;
  /* 14px */
  --font-size-base: 1rem;
  /* 16px */
  --font-size-lg: 1.125rem;
  /* 18px */
  --font-size-xl: 1.25rem;
  /* 20px */
  --font-size-2xl: 1.5rem;
  /* 24px */
  --font-size-3xl: 1.875rem;
  /* 30px */
  --font-size-4xl: 2.25rem;
  /* 36px */
  --font-size-5xl: 3rem;
  /* 48px */
  --font-size-6xl: 3.75rem;
  /* 60px */
  --font-size-7xl: 4.5rem;
  /* 72px */

  /* Font Weights */
  --font-weight-normal: 400;
  --font-weight-medium: 500;
  --font-weight-semibold: 600;
  --font-weight-bold: 700;

  /* Line Heights */
  --line-height-tight: 1.2;
  --line-height-normal: 1.6;
  --line-height-relaxed: 1.8;
}

/* Heading Styles */
h1,
h2,
h3,
h4,
h5,
h6 {
  font-family: var(--font-heading);
  font-weight: var(--font-weight-bold);
  line-height: var(--line-height-tight);
  color: var(--color-craft-black);
  margin-bottom: 1rem;
}

/* Fluid Typography with clamp() */
h1 {
  font-size: clamp(2rem, 5vw + 1rem, 3.75rem);
  /* 32px - 60px */
  letter-spacing: -0.02em;
}

h2 {
  font-size: clamp(1.75rem, 3vw + 1rem, 2.25rem);
  /* 28px - 36px */
  letter-spacing: -0.01em;
}

h3 {
  font-size: clamp(1.5rem, 2vw + 0.5rem, 1.875rem);
  /* 24px - 30px */
}

h4 {
  font-size: clamp(1.25rem, 1.5vw + 0.5rem, 1.5rem);
  /* 20px - 24px */
}

h5 {
  font-size: clamp(1.125rem, 1vw + 0.5rem, 1.25rem);
  /* 18px - 20px */
}

h6 {
  font-size: clamp(1rem, 0.5vw + 0.5rem, 1.125rem);
  /* 16px - 18px */
}

/* Body Text */
p {
  margin-bottom: 1rem;
  line-height: var(--line-height-normal);
  font-size: clamp(1rem, 0.5vw + 0.875rem, 1.125rem);
  /* 16px - 18px */
}

/* ============================================
   4. Spacing System (8px base)
   ============================================ */

:root {
  --spacing-xs: 0.25rem;
  /* 4px */
  --spacing-sm: 0.5rem;
  /* 8px */
  --spacing-md: 1rem;
  /* 16px */
  --spacing-lg: 1.5rem;
  /* 24px */
  --spacing-xl: 2rem;
  /* 32px */
  --spacing-2xl: 3rem;
  /* 48px */
  --spacing-3xl: 4rem;
  /* 64px */
  --spacing-4xl: 6rem;
  /* 96px */
  --spacing-5xl: 8rem;
  /* 128px */
  --spacing-6xl: 12rem;
  /* 192px */
}

/* ============================================
   5. Layout Tokens
   ============================================ */

:root {
  /* Responsive Breakpoints */
  --breakpoint-sm: 640px;
  /* Small tablets */
  --breakpoint-md: 768px;
  /* Tablets */
  --breakpoint-lg: 1024px;
  /* Small desktops */
  --breakpoint-xl: 1280px;
  /* Large desktops */
  --breakpoint-2xl: 1536px;
  /* Extra large screens */

  /* Container Widths */
  --container-sm: 640px;
  --container-md: 768px;
  --container-lg: 1024px;
  --container-xl: 1280px;
  --container-2xl: 1536px;

  /* Border Radius */
  --radius-sm: 0.25rem;
  /* 4px */
  --radius-md: 0.5rem;
  /* 8px */
  --radius-lg: 1rem;
  /* 16px */
  --radius-xl: 1.5rem;
  /* 24px */
  --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 ease-out;
  --transition-base: 300ms ease-out;
  --transition-slow: 500ms ease-out;

  /* Z-index */
  --z-base: 1;
  --z-dropdown: 100;
  --z-sticky: 200;
  --z-fixed: 300;
  --z-modal: 400;
  --z-popover: 500;
  --z-tooltip: 600;
}

/* ============================================
   6. Container & Layout Utilities
   ============================================ */

.container {
  width: 100%;
  max-width: var(--container-xl);
  margin-left: auto;
  margin-right: auto;
  padding-left: var(--spacing-md);
  /* 16px on mobile */
  padding-right: var(--spacing-md);
}

/* Responsive container padding */
@media (min-width: 640px) {
  .container {
    padding-left: var(--spacing-lg);
    /* 24px on tablet */
    padding-right: var(--spacing-lg);
  }
}

@media (min-width: 1024px) {
  .container {
    padding-left: var(--spacing-xl);
    /* 32px on desktop */
    padding-right: var(--spacing-xl);
  }
}

.container-wide {
  max-width: var(--container-2xl);
}

.container-narrow {
  max-width: var(--container-lg);
}

/* Section Spacing */
.section {
  padding-top: var(--spacing-5xl);
  padding-bottom: var(--spacing-5xl);
}

.section-sm {
  padding-top: var(--spacing-4xl);
  padding-bottom: var(--spacing-4xl);
}

.section-lg {
  padding-top: var(--spacing-6xl);
  padding-bottom: var(--spacing-6xl);
}

/* ============================================
   7. Utility Classes
   ============================================ */

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

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

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

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

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

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

.font-heading {
  font-family: var(--font-heading);
}

.font-body {
  font-family: var(--font-body);
}

/* Background Utilities */
.bg-white {
  background-color: var(--color-white);
}

.bg-grey {
  background-color: var(--color-grey-100);
}

.bg-craft-black {
  background-color: var(--color-craft-black);
}

.bg-digital-blue {
  background-color: var(--color-digital-blue);
}

/* Flex Utilities */
.flex {
  display: flex;
}

.flex-col {
  flex-direction: column;
}

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

.justify-center {
  justify-content: center;
}

.justify-between {
  justify-content: space-between;
}

.gap-sm {
  gap: var(--spacing-sm);
}

.gap-md {
  gap: var(--spacing-md);
}

.gap-lg {
  gap: var(--spacing-lg);
}

.gap-xl {
  gap: var(--spacing-xl);
}

/* Grid Utilities - Mobile First */
.grid {
  display: grid;
  gap: var(--spacing-lg);
  /* 24px on mobile */
}

/* Responsive grid gaps */
@media (min-width: 640px) {
  .grid {
    gap: var(--spacing-xl);
    /* 32px on tablet */
  }
}

@media (min-width: 1024px) {
  .grid {
    gap: var(--spacing-2xl);
    /* 48px on desktop */
  }
}

/* Grid columns - Mobile first (all start as 1 column) */
.grid-cols-1 {
  grid-template-columns: 1fr;
}

.grid-cols-2 {
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .grid-cols-2 {
    grid-template-columns: repeat(2, 1fr);
  }
}

.grid-cols-3 {
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .grid-cols-3 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .grid-cols-3 {
    grid-template-columns: repeat(3, 1fr);
  }
}

.grid-cols-4 {
  grid-template-columns: 1fr;
}

@media (min-width: 640px) {
  .grid-cols-4 {
    grid-template-columns: repeat(2, 1fr);
  }
}

@media (min-width: 1024px) {
  .grid-cols-4 {
    grid-template-columns: repeat(3, 1fr);
  }
}

@media (min-width: 1280px) {
  .grid-cols-4 {
    grid-template-columns: repeat(4, 1fr);
  }
}

/* ============================================
   8. Responsive Section Spacing
   ============================================ */

@media (max-width: 768px) {
  .section {
    padding-top: var(--spacing-4xl);
    padding-bottom: var(--spacing-4xl);
  }
}

@media (max-width: 480px) {
  .section {
    padding-top: var(--spacing-3xl);
    padding-bottom: var(--spacing-3xl);
  }
}

/* ============================================
   9. Links & Interactive Elements
   ============================================ */

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

a:hover {
  color: var(--color-craft-black);
}

/* ============================================
   10. Selection & Focus States
   ============================================ */

::selection {
  background-color: var(--color-electric-mint);
  color: var(--color-craft-black);
}

:focus-visible {
  outline: 2px solid var(--color-digital-blue);
  outline-offset: 2px;
}

/* ============================================
   11. Smooth Animations
   ============================================ */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(20px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

@keyframes slideInLeft {
  from {
    opacity: 0;
    transform: translateX(-30px);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

@keyframes slideInRight {
  from {
    opacity: 0;
    transform: translateX(30px);
  }

  to {
    opacity: 1;
    transform: translateX(0);
  }
}

.fade-in {
  animation: fadeIn 0.6s ease-out;
}

.slide-in-left {
  animation: slideInLeft 0.6s ease-out;
}

.slide-in-right {
  animation: slideInRight 0.6s ease-out;
}