@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

:root {
    --primary: #4f46e5;
    --primary-hover: #4338ca;
    --secondary: #64748b;
    --success: #10b981;
    --danger: #ef4444;
    --warning: #f59e0b;
    
    /* Variables for Dark/Light mode */
    --bg-main: #0f172a;
    --bg-card: #1e293b;
    --bg-nav: rgba(15, 23, 42, 0.9);
    --text-main: #f1f5f9;
    --text-dim: #94a3b8;
    --text-inverse: #ffffff;
    --border: #334155;
    --shadow: 0 10px 15px -3px rgba(0, 0, 0, 0.3);
    --radius: 12px;
}

[data-theme="light"] {
    --bg-main: #ffffff;
    --bg-card: #f8fafc;
    --bg-nav: rgba(255, 255, 255, 0.95);
    --text-main: #0f172a;
    --text-dim: #64748b;
    --text-inverse: #0f172a;
    --border: #e2e8f0;
    --shadow: 0 4px 6px -1px rgba(0, 0, 0, 0.1);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    transition: background-color 0.2s, color 0.2s, border-color 0.2s;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--bg-main);
    color: var(--text-main);
    line-height: 1.5;
    -webkit-font-smoothing: antialiased;
    overflow-x: hidden;
}

.container {
    max-width: 1280px;
    margin: 0 auto;
    padding: 0 1.5rem;
}

/* Typography */
h1, h2, h3, h4 {
    font-weight: 700;
    line-height: 1.2;
    margin-bottom: 1rem;
}

a {
    color: inherit;
    text-decoration: none;
    transition: color 0.2s;
}

/* Navigation */
nav {
    position: fixed;
    top: 0;
    left: 0;
    right: 0;
    z-index: 1000;
    background-color: var(--bg-nav);
    backdrop-filter: blur(10px);
    border-bottom: 1px solid var(--border);
    height: 72px;
    display: flex;
    align-items: center;
}

.nav-inner {
    display: flex;
    justify-content: space-between;
    align-items: center;
    width: 100%;
}

.logo {
    font-size: 1.25rem;
    font-weight: 800;
    letter-spacing: -0.5px;
    color: var(--primary);
}

.nav-links {
    display: flex;
    gap: 2rem;
    align-items: center;
}

.nav-links a {
    font-size: 0.875rem;
    font-weight: 500;
    color: var(--text-dim);
}

.nav-links a:hover, .nav-links a.active {
    color: var(--primary);
}

.mobile-toggle {
    display: none;
    cursor: pointer;
}

/* Buttons */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.625rem 1.25rem;
    border-radius: var(--radius);
    font-weight: 600;
    font-size: 0.875rem;
    cursor: pointer;
    border: 1px solid transparent;
    transition: transform 0.1s, box-shadow 0.2s;
}

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

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

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

.btn-outline:hover {
    background: var(--bg-card);
}

/* Footer */
footer {
    padding: 4rem 0 2rem;
    background: var(--bg-card);
    border-top: 1px solid var(--border);
    margin-top: 4rem;
}

/* Responsive Overrides */
@media (max-width: 768px) {
    .nav-links {
        display: none; /* Will be toggled by JS */
    }
    
    .mobile-toggle {
        display: block;
    }
    
    .nav-links.active {
        display: flex;
        flex-direction: column;
        position: absolute;
        top: 72px;
        left: 0;
        right: 0;
        background: var(--bg-card);
        padding: 2rem;
        border-bottom: 1px solid var(--border);
        gap: 1.5rem;
    }
}

/* Utils */
.sr-only {
    position: absolute;
    width: 1px;
    height: 1px;
    padding: 0;
    margin: -1px;
    overflow: hidden;
    clip: rect(0, 0, 0, 0);
    white-space: nowrap;
    border-width: 0;
}