:root {
    --bg-gradient: linear-gradient(135deg, #1a1a2e 0%, #16213e 100%);
    --container-bg: rgba(255, 255, 255, 0.05);
    --secondary-bg: rgba(0, 0, 0, 0.2);
    --text-color: #e0e0e0;
    --text-muted: #b0b0b0;
    --accent-color: #007bff;
    --accent-hover: #0056b3;
    --circle-bg: rgba(255, 255, 255, 0.1);
    --header-bg: rgba(26, 26, 46, 0.9);
}

[data-theme="light"] {
    --bg-gradient: linear-gradient(135deg, #f8f9fa 0%, #e9ecef 100%);
    --container-bg: white;
    --secondary-bg: #f1f3f5;
    --text-color: #212529;
    --text-muted: #6c757d;
    --accent-color: #007bff;
    --accent-hover: #0056b3;
    --circle-bg: #dee2e6;
    --header-bg: rgba(255, 255, 255, 0.9);
}

* {
    box-sizing: border-box;
    scroll-behavior: smooth;
}

body {
    font-family: 'Roboto', sans-serif;
    line-height: 1.6;
    color: var(--text-color);
    background: var(--bg-gradient);
    margin: 0;
    transition: background 0.3s ease, color 0.3s ease;
    min-height: 100vh;
}

.container {
    max-width: 1000px;
    margin: 0 auto;
    padding: 0 20px;
}

/* Header & Nav */
header {
    background: var(--header-bg);
    backdrop-filter: blur(10px);
    position: sticky;
    top: 0;
    z-index: 1000;
    box-shadow: 0 2px 10px rgba(0,0,0,0.1);
}

nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 15px 20px;
    max-width: 1200px;
    margin: 0 auto;
}

.logo {
    font-size: 24px;
    font-weight: bold;
    color: var(--accent-color);
}

nav ul {
    display: flex;
    list-style: none;
    margin: 0;
    padding: 0;
}

nav ul li {
    margin: 0 15px;
}

nav ul li a {
    text-decoration: none;
    color: var(--text-color);
    font-weight: 500;
    transition: color 0.3s;
}

nav ul li a:hover {
    color: var(--accent-color);
}

/* Hero Section */
.hero-section {
    padding: 80px 0;
    text-align: center;
}

h1 {
    font-size: 3rem;
    margin-bottom: 10px;
}

.subtitle {
    font-size: 1.2rem;
    color: var(--text-muted);
    margin-bottom: 40px;
}

/* Lotto Container */
.numbers-container {
    display: flex;
    justify-content: center;
    gap: 15px;
    margin-bottom: 40px;
    flex-wrap: wrap;
}

.number-circle {
    width: 65px;
    height: 65px;
    border-radius: 50%;
    display: flex;
    justify-content: center;
    align-items: center;
    font-size: 1.5rem;
    font-weight: bold;
    color: white;
    background-color: var(--circle-bg);
    box-shadow: 0 4px 15px rgba(0, 0, 0, 0.1);
    transition: transform 0.3s ease, background-color 0.3s ease;
}

.number-circle:hover {
    transform: scale(1.1);
}

#generate-btn {
    padding: 15px 40px;
    font-size: 1.2rem;
    font-weight: bold;
    color: white;
    background-color: var(--accent-color);
    border: none;
    border-radius: 30px;
    cursor: pointer;
    transition: background-color 0.3s, transform 0.2s, box-shadow 0.3s;
    box-shadow: 0 4px 15px rgba(0, 123, 255, 0.3);
}

#generate-btn:hover {
    background-color: var(--accent-hover);
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(0, 123, 255, 0.4);
}

/* Content Sections */
.content-section {
    padding: 60px 0;
}

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

.text-content {
    max-width: 800px;
}

h2 {
    font-size: 2rem;
    margin-bottom: 20px;
}

.features-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(250px, 1fr));
    gap: 30px;
    margin-top: 40px;
}

.feature-card {
    background: var(--container-bg);
    padding: 30px;
    border-radius: 15px;
    box-shadow: 0 4px 15px rgba(0,0,0,0.05);
}

.feature-card h3 {
    margin-top: 0;
    color: var(--accent-color);
}

/* Footer */
footer {
    padding: 40px 0;
    text-align: center;
    border-top: 1px solid var(--circle-bg);
}

.footer-links {
    list-style: none;
    padding: 0;
    display: flex;
    justify-content: center;
    gap: 20px;
    margin-top: 20px;
}

.footer-links a {
    text-decoration: none;
    color: var(--text-muted);
}

/* Theme Toggle */
#theme-btn {
    background: none;
    border: none;
    font-size: 20px;
    cursor: pointer;
    padding: 8px;
    border-radius: 50%;
    transition: background 0.3s;
}

#theme-btn:hover {
    background: var(--circle-bg);
}

@media (max-width: 600px) {
    h1 { font-size: 2rem; }
    .number-circle { width: 50px; height: 50px; font-size: 1.2rem; }
}