/* Reset & Base Styles */
* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Inter', sans-serif;
}

body {
    background-color: #0b1120;
    color: #e2e8f0;
    line-height: 1.6;
}

/* Header & Nav Styling */
header {
    background: #0f172a;
    padding: 18px 40px;
    border-bottom: 1px solid #1e293b;
}

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

nav .logo {
    font-size: 1.5rem;
    font-weight: 800;
    color: #38bdf8;
    letter-spacing: 0.5px;
}

nav a {
    color: #94a3b8;
    text-decoration: none;
    margin-left: 20px;
    font-weight: 600;
    transition: color 0.3s ease;
}

nav a:hover {
    color: #38bdf8;
}

/* Main Container */
.container {
    max-width: 1000px;
    margin: 40px auto;
    padding: 0 20px;
}

.page-title {
    text-align: center;
    font-size: 2.5rem;
    font-weight: 800;
    color: #ffffff;
    margin-bottom: 8px;
}

.page-subtitle {
    text-align: center;
    color: #94a3b8;
    margin-bottom: 40px;
    font-size: 1rem;
}

/* Card Sections */
.roadmap-card {
    background: #1e293b;
    border: 1px solid #334155;
    border-radius: 12px;
    padding: 30px;
    margin-bottom: 30px;
    box-shadow: 0 10px 25px -5px rgba(0, 0, 0, 0.3);
}

.roadmap-card h2 {
    color: #38bdf8;
    font-size: 1.6rem;
    margin-bottom: 15px;
    padding-bottom: 10px;
    border-bottom: 2px solid #334155;
}

.sub-section {
    margin-top: 20px;
    background: #0f172a;
    padding: 20px;
    border-radius: 8px;
    border-left: 4px solid #38bdf8;
}

.sub-section h3 {
    color: #facc15;
    font-size: 1.2rem;
    margin-bottom: 10px;
}

.sub-section p {
    color: #cbd5e1;
    font-size: 0.95rem;
    margin-bottom: 12px;
}

/* Roadmap Item Lists */
.roadmap-list {
    list-style: none;
    padding-left: 5px;
}

.roadmap-list li {
    position: relative;
    padding-left: 25px;
    margin-bottom: 10px;
    color: #e2e8f0;
}

.roadmap-list li::before {
    content: "✔";
    position: absolute;
    left: 0;
    color: #38bdf8;
    font-weight: bold;
}

/* Back Button Styling */
.btn-container {
    text-align: center;
    margin-top: 40px;
    margin-bottom: 20px;
}

.back-btn {
    background: #2563eb;
    color: #ffffff;
    text-decoration: none;
    padding: 12px 28px;
    border-radius: 8px;
    font-weight: 700;
    display: inline-block;
    transition: background 0.3s ease, transform 0.2s ease;
}

.back-btn:hover {
    background: #1d4ed8;
    transform: translateY(-2px);
}