/**
 * Base styles - Reset, variables, and typography
 */

/* CSS Custom Properties */
:root {
    /* Colors */
    --color-primary: #6366f1;
    --color-primary-dark: #d8c4ff;
    --color-primary-light: #818cf8;

    --color-secondary: #ec4899;
    --color-secondary-dark: #db2777;

    --color-success: #10b981;
    --color-warning: #f59e0b;
    --color-error: #ef4444;

    --color-gray-50: #f9fafb;
    --color-gray-100: #f3f4f6;
    --color-gray-200: #e5e7eb;
    --color-gray-300: #d1d5db;
    --color-gray-400: #9ca3af;
    --color-gray-500: #6b7280;
    --color-gray-600: #4b5563;
    --color-gray-700: #374151;
    --color-gray-800: #1f2937;
    --color-gray-900: #111827;

    --color-white: #ffffff;
    --color-black: #000000;

    /* Background */
    --bg-primary: var(--color-gray-900);
    --bg-secondary: var(--color-gray-800);
    --bg-card: rgba(31, 41, 55, 0.95);
    --bg-overlay: rgba(0, 0, 0, 0.7);

    /* Text */
    --text-primary: var(--color-primary-dark);
    --text-secondary: var(--color-gray-400);
    --text-muted: var(--color-gray-500);

    /* Borders */
    --border-color: var(--color-gray-700);
    --border-radius: 8px;
    --border-radius-lg: 12px;
    --border-radius-sm: 4px;

    /* Shadows */
    --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.3);
    --shadow: 0 4px 6px rgba(0, 0, 0, 0.3);
    --shadow-lg: 0 10px 25px rgba(0, 0, 0, 0.4);

    /* 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: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, 'Helvetica Neue', Arial, sans-serif;
    --font-size-xs: 0.75rem;
    --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: 2rem;

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition: 200ms ease;
    --transition-slow: 300ms ease;

    /* Z-index layers */
    --z-dropdown: 100;
    --z-sticky: 200;
    --z-modal-backdrop: 300;
    --z-modal: 400;
    --z-toast: 500;

    /* Layout heights */
    --nav-height: 50px;
    --nav-height-mobile: 149px;
}

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

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

body {
    font-family: var(--font-family);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--text-primary);
    background-color: var(--bg-primary);
    background-image: url('../notes3.jpg');
    background-size: cover;
    background-position: center;
    background-attachment: fixed;
    min-height: 100vh;
    overscroll-behavior-x: none;
}

/* Typography */
h1, h2, h3, h4, h5, h6 {
    font-weight: 600;
    line-height: 1.3;
    margin-bottom: var(--spacing-sm);
}

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

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

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

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

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

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

/* Form elements */
button,
input,
select,
textarea {
    font-family: inherit;
    font-size: inherit;
    line-height: inherit;
}

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

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

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

/* Scrollbar */
::-webkit-scrollbar {
    width: 8px;
    height: 8px;
}

::-webkit-scrollbar-track {
    background: var(--color-gray-800);
}

::-webkit-scrollbar-thumb {
    background: var(--color-gray-600);
    border-radius: 4px;
}

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

/* Utility classes */
.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;
}

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

/* Loading spinner */
.loading {
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: center;
    gap: var(--spacing-md);
    padding: var(--spacing-2xl);
    color: var(--text-secondary);
    font-size: var(--font-size-lg);
}

.loading i {
    font-size: var(--font-size-3xl);
    color: var(--color-primary);
}

/* Error message */
.error-message {
    background: var(--bg-card);
    border: 1px solid var(--color-error);
    border-radius: var(--border-radius);
    padding: var(--spacing-xl);
    margin: var(--spacing-xl);
    text-align: center;
}

.error-message h2 {
    color: var(--color-error);
}

.error-message pre {
    background: var(--color-gray-800);
    padding: var(--spacing-md);
    border-radius: var(--border-radius-sm);
    overflow-x: auto;
    font-size: var(--font-size-sm);
    margin-top: var(--spacing-md);
}