/**
 * ============================================
 * DOCSEN  - Base CSS
 * Reset + CSS Variables + Typography
 * ============================================
 */

/* ============================================
   CSS CUSTOM PROPERTIES (Variables)
   ============================================ */
:root {
    /* Primary Colors - Blue/White theme */
    --color-primary: #1b10b9;
    --color-primary-light: #e6e8ff;
    --color-primary-dark: #032b7a;
    --color-primary-subtle: #eef0ff;

    /* Secondary Colors (cool blues) */
    --color-secondary: #043796;
    --color-secondary-light: #e6e8ff;
    --color-secondary-dark: #021f57;
    
    /* Accent Colors (blue-only) */
    --color-accent: #2563eb;
    --color-accent-light: #dbeafe;
    --color-accent-dark: #1e3a8a;
    
    /* Neutral Colors */
    --color-white: #FFFFFF;
    --color-off-white: #FAFBFC;
    --color-gray-50: #F8F9FA;
    --color-gray-100: #F1F3F4;
    --color-gray-200: #E8EAED;
    --color-gray-300: #DADCE0;
    --color-gray-400: #BDC1C6;
    --color-gray-500: #9AA0A6;
    --color-gray-600: #80868B;
    --color-gray-700: #5F6368;
    --color-gray-800: #3C4043;
    --color-gray-900: #202124;
    --color-black: #1A1A1A;
    
    /* Semantic Colors (kept in blue spectrum for harmony) */
    --color-success: #1e40af;
    --color-success-light: #e0e7ff;
    --color-warning: #2563eb;
    --color-warning-light: #dbeafe;
    --color-error: #0f172a;
    --color-error-light: #e5e7eb;
    --color-info: #1d4ed8;
    --color-info-light: #e0e7ff;
    
    /* Background Colors */
    --bg-primary: var(--color-white);
    --bg-secondary: var(--color-gray-50);
    --bg-tertiary: var(--color-gray-100);
    --bg-overlay: rgba(0, 0, 0, 0.5);
    
    /* Text Colors */
    --text-primary: var(--color-gray-900);
    --text-secondary: var(--color-gray-700);
    --text-tertiary: var(--color-gray-600);
    --text-muted: var(--color-gray-500);
    --text-inverse: var(--color-white);
    
    /* Typography */
    --font-family-primary: 'Nunito Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    --font-family-heading: 'DM Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    
    /* Font Sizes - Mobile First */
    --font-size-xs: 0.75rem;     /* 12px */
    --font-size-sm: 0.875rem;    /* 14px */
    --font-size-base: 1rem;      /* 16px */
    --font-size-md: 1.125rem;    /* 18px */
    --font-size-lg: 1.25rem;     /* 20px */
    --font-size-xl: 1.5rem;      /* 24px */
    --font-size-2xl: 1.875rem;   /* 30px */
    --font-size-3xl: 2.25rem;    /* 36px */
    --font-size-4xl: 3rem;       /* 48px */
    
    /* Font Weights */
    --font-weight-normal: 400;
    --font-weight-medium: 500;
    --font-weight-semibold: 600;
    --font-weight-bold: 700;
    
    /* Line Heights */
    --line-height-tight: 1.25;
    --line-height-normal: 1.5;
    --line-height-relaxed: 1.75;
    
    /* Spacing Scale */
    --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 */
    
    /* Border Radius */
    --radius-sm: 0.25rem;   /* 4px */
    --radius-md: 0.5rem;    /* 8px */
    --radius-lg: 0.75rem;   /* 12px */
    --radius-xl: 1rem;      /* 16px */
    --radius-2xl: 1.5rem;   /* 24px */
    --radius-full: 9999px;
    
    /* Shadows */
    --shadow-xs: 0 1px 2px rgba(0, 0, 0, 0.05);
    --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.1), 0 1px 2px rgba(0, 0, 0, 0.06);
    --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);
    --shadow-xl: 0 20px 25px -5px rgba(0, 0, 0, 0.1), 0 10px 10px -5px rgba(0, 0, 0, 0.04);
    --shadow-focus: 0 0 0 3px rgba(45, 43, 114, 0.3);
    
    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 200ms ease;
    --transition-slow: 300ms ease;
    --transition-bounce: 300ms cubic-bezier(0.68, -0.55, 0.265, 1.55);
    
    /* Z-Index Scale */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal-backdrop: 300;
    --z-modal: 400;
    --z-toast: 500;
    
    /* Container Widths */
    --container-sm: 640px;
    --container-md: 768px;
    --container-lg: 1024px;
    --container-xl: 1200px;
    
    /* Touch Target Size (minimum 44px for accessibility) */
    --touch-target: 48px;
}

/* ============================================
   CSS RESET (Modern)
   ============================================ */
*,
*::before,
*::after {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
}
::selection {
    background-color: var(--color-accent);
    color: var(--color-white);
}

html {
    font-size: 16px;
    -webkit-text-size-adjust: 100%;
    -webkit-tap-highlight-color: transparent;
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-family-primary);
    font-size: var(--font-size-base);
    font-weight: var(--font-weight-normal);
    line-height: var(--line-height-normal);
    color: var(--text-primary);
    background-color: var(--bg-primary);
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
    min-height: 100vh;
    overflow-x: hidden;
}

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

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

button {
    cursor: pointer;
    border: none;
    background: none;
}

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

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

/* Tables */
table {
    border-collapse: collapse;
    border-spacing: 0;
}

/* Headings */
h1, h2, h3, h4, h5, h6 {
    font-family: var(--font-family-heading);
    font-weight: var(--font-weight-bold);
    line-height: var(--line-height-tight);
    color: var(--text-primary);
}

h1 {
    font-size: var(--font-size-2xl);
}

h2 {
    font-size: var(--font-size-xl);
}

h3 {
    font-size: var(--font-size-lg);
}

h4 {
    font-size: var(--font-size-md);
}

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

p:last-child {
    margin-bottom: 0;
}

/* Focus Styles (Accessibility) */
:focus-visible {
    outline: 2px solid var(--color-primary);
    outline-offset: 2px;
}

/* Remove default focus for mouse users */
:focus:not(:focus-visible) {
    outline: none;
}

/* Selection */
::selection {
    background-color: var(--color-primary);
    color: var(--color-white);
}

/* Scrollbar Styling */
::-webkit-scrollbar {
    width: 6px;
    height: 6px;
}

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

::-webkit-scrollbar-thumb {
    background: var(--color-gray-400);
    border-radius: var(--radius-full);
}

::-webkit-scrollbar-thumb:hover {
    background: var(--color-gray-500);
}

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

/* Screen Reader Only */
.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;
}

/* Hide visually but keep for screen readers */
.visually-hidden {
    clip: rect(0 0 0 0);
    clip-path: inset(50%);
    height: 1px;
    overflow: hidden;
    position: absolute;
    white-space: nowrap;
    width: 1px;
}

/* Text utilities */
.text-center { text-align: center; }
.text-left { text-align: left; }
.text-right { text-align: right; }

.text-primary { color: var(--color-primary); }
.text-secondary { color: var(--text-secondary); }
.text-muted { color: var(--text-muted); }
.text-success { color: var(--color-success); }
.text-error { color: var(--color-error); }

/* Font weights */
.font-normal { font-weight: var(--font-weight-normal); }
.font-medium { font-weight: var(--font-weight-medium); }
.font-semibold { font-weight: var(--font-weight-semibold); }
.font-bold { font-weight: var(--font-weight-bold); }

/* Display utilities */
.hidden { display: none !important; }
.block { display: block; }
.inline-block { display: inline-block; }
.flex { display: flex; }
.inline-flex { display: inline-flex; }
.grid { display: grid; }

/* Loading State */
.loading {
    pointer-events: none;
    opacity: 0.7;
}

/* Fade animations */
.fade-in {
    animation: fadeIn var(--transition-base) ease-out;
}

.fade-out {
    animation: fadeOut var(--transition-base) ease-out;
}

@keyframes fadeIn {
    from { opacity: 0; }
    to { opacity: 1; }
}

@keyframes fadeOut {
    from { opacity: 1; }
    to { opacity: 0; }
}

/* Slide animations */
.slide-up {
    animation: slideUp var(--transition-slow) ease-out;
}

.slide-down {
    animation: slideDown var(--transition-slow) ease-out;
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideDown {
    from {
        opacity: 0;
        transform: translateY(-20px);
    }
    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Pulse animation for loading states */
@keyframes pulse {
    0%, 100% { opacity: 1; }
    50% { opacity: 0.5; }
}

.animate-pulse {
    animation: pulse 2s cubic-bezier(0.4, 0, 0.6, 1) infinite;
}

/* Spin animation for loaders */
@keyframes spin {
    from { transform: rotate(0deg); }
    to { transform: rotate(360deg); }
}

.animate-spin {
    animation: spin 1s linear infinite;
}

/* Shake animation for errors */
@keyframes shake {
    0%, 100% { transform: translateX(0); }
    10%, 30%, 50%, 70%, 90% { transform: translateX(-4px); }
    20%, 40%, 60%, 80% { transform: translateX(4px); }
}

.animate-shake {
    animation: shake 0.5s ease-in-out;
}