/* ============================================
   FlowChart Academy - Global Styles
   ============================================ */

/* --- CSS Variables --- */
:root {
    /* Colors */
    --color-primary: #2563eb;
    --color-primary-light: #dbeafe;
    --color-primary-dark: #1d4ed8;
    --color-secondary: #7c3aed;
    --color-success: #16a34a;
    --color-warning: #d97706;
    --color-danger: #dc2626;

    /* Neutrals */
    --color-bg: #f8fafc;
    --color-surface: #ffffff;
    --color-border: #e2e8f0;
    --color-text: #1e293b;
    --color-text-light: #64748b;
    --color-text-lighter: #94a3b8;

    /* Flowchart shape colors */
    --fc-terminal: #7c3aed;
    --fc-terminal-bg: #f5f3ff;
    --fc-process: #2563eb;
    --fc-process-bg: #eff6ff;
    --fc-decision: #d97706;
    --fc-decision-bg: #fffbeb;
    --fc-io: #16a34a;
    --fc-io-bg: #f0fdf4;
    --fc-arrow: #475569;
    --fc-active: #2563eb;
    --fc-active-glow: rgba(37, 99, 235, 0.4);
    --fc-visited: #cbd5e1;

    /* Typography */
    --font-body: 'Segoe UI', system-ui, -apple-system, sans-serif;
    --font-mono: 'Cascadia Code', 'Fira Code', 'Consolas', monospace;
    --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;

    /* Spacing */
    --space-xs: 0.25rem;
    --space-sm: 0.5rem;
    --space-md: 1rem;
    --space-lg: 1.5rem;
    --space-xl: 2rem;
    --space-2xl: 3rem;
    --space-3xl: 4rem;

    /* Layout */
    --max-width: 1200px;
    --nav-height: 64px;
    --sidebar-width: 260px;
    --border-radius: 8px;
    --border-radius-lg: 12px;

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

    /* Transitions */
    --transition-fast: 150ms ease;
    --transition-base: 250ms ease;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: var(--font-body);
    font-size: var(--font-size-base);
    line-height: 1.6;
    color: var(--color-text);
    background-color: var(--color-bg);
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

img, svg {
    max-width: 100%;
    display: block;
}

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

a:hover {
    color: var(--color-primary-dark);
}

h1, h2, h3, h4, h5, h6 {
    line-height: 1.3;
    font-weight: 600;
}

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

code {
    font-family: var(--font-mono);
    font-size: 0.9em;
    background-color: var(--color-primary-light);
    padding: 0.15em 0.4em;
    border-radius: 4px;
}

pre code {
    background: none;
    padding: 0;
}

/* --- Navigation --- */
.site-header {
    position: sticky;
    top: 0;
    z-index: 100;
    background: var(--color-surface);
    border-bottom: 1px solid var(--color-border);
    box-shadow: var(--shadow-sm);
}

.main-nav {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-lg);
    height: var(--nav-height);
    display: flex;
    align-items: center;
    justify-content: space-between;
}

.nav-logo {
    display: flex;
    align-items: center;
    gap: var(--space-sm);
    font-weight: 700;
    font-size: var(--font-size-lg);
    color: var(--color-text);
}

.nav-logo:hover {
    color: var(--color-primary);
}

.logo-icon {
    color: var(--color-primary);
}

.nav-links {
    display: flex;
    list-style: none;
    gap: var(--space-xs);
}

.nav-links a {
    display: block;
    padding: var(--space-sm) var(--space-md);
    border-radius: var(--border-radius);
    color: var(--color-text-light);
    font-weight: 500;
    transition: all var(--transition-fast);
}

.nav-links a:hover {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
}

.nav-links a.active {
    color: var(--color-primary);
    background-color: var(--color-primary-light);
}

/* Mobile nav toggle */
.nav-toggle {
    display: none;
    flex-direction: column;
    gap: 5px;
    background: none;
    border: none;
    cursor: pointer;
    padding: var(--space-sm);
}

.nav-toggle span {
    display: block;
    width: 24px;
    height: 2px;
    background: var(--color-text);
    transition: all var(--transition-fast);
}

/* --- Container --- */
.container {
    max-width: var(--max-width);
    margin: 0 auto;
    padding: 0 var(--space-lg);
}

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

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

.btn-primary:hover {
    background: var(--color-primary-dark);
    color: white;
}

.btn-outline {
    background: transparent;
    color: var(--color-primary);
    border-color: var(--color-primary);
}

.btn-outline:hover {
    background: var(--color-primary);
    color: white;
}

.btn-lg {
    padding: var(--space-md) var(--space-xl);
    font-size: var(--font-size-lg);
}

/* --- Footer --- */
.site-footer {
    margin-top: auto;
    background: var(--color-surface);
    border-top: 1px solid var(--color-border);
    padding: var(--space-xl) var(--space-lg);
    text-align: center;
    color: var(--color-text-light);
    font-size: var(--font-size-sm);
}

/* --- Responsive --- */
@media (max-width: 768px) {
    .nav-toggle {
        display: flex;
    }

    .nav-links {
        display: none;
        position: absolute;
        top: var(--nav-height);
        left: 0;
        right: 0;
        background: var(--color-surface);
        flex-direction: column;
        padding: var(--space-md);
        border-bottom: 1px solid var(--color-border);
        box-shadow: var(--shadow-md);
    }

    .nav-links.open {
        display: flex;
    }

    h1 { font-size: var(--font-size-2xl); }
    h2 { font-size: var(--font-size-xl); }
}