:root {
    --primary-color: #13ec6a;
    --primary-dark: #0fae4e;
    --secondary-color: #4cc9f0;
    --accent-color: #f72585;
    --background-color: #102217;
    --text-main: #f6f8f7;
    --text-secondary: #a0a0a0;
    --card-bg: #162b20;
    --border-color: #234832;
    --card-shadow: 0 10px 30px -5px rgba(0, 0, 0, 0.5);
    --hover-shadow: 0 20px 40px -5px rgba(0, 0, 0, 0.6);
    --gradient-header: linear-gradient(135deg, #13ec6a 0%, #0fae4e 100%);
    --gradient-icon: linear-gradient(135deg, #234832 0%, #162b20 100%);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Inter', sans-serif;
    background-color: var(--background-color);
    color: var(--text-main);
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    background-image:
        radial-gradient(at 0% 0%, rgba(19, 236, 106, 0.1) 0px, transparent 50%),
        radial-gradient(at 100% 0%, rgba(247, 37, 133, 0.05) 0px, transparent 50%);
    /* Subtle texture or pattern if preferred */
}

/* Header Styling */
header {
    background: var(--card-bg);
    color: var(--text-main);
    padding: 1.5rem 2rem;
    text-align: center;
    box-shadow: 0 4px 20px rgba(0, 0, 0, 0.05);
    position: relative;
    z-index: 10;
}

header h1 {
    font-family: 'Poppins', sans-serif;
    font-weight: 700;
    font-size: 2.5rem;
    margin-bottom: 0.25rem;
    color: var(--primary-color);
    background: var(--gradient-header);
    background-clip: text;
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    display: inline-block;
}

header p {
    font-size: 1.125rem;
    color: var(--text-secondary);
    font-weight: 500;
}

/* Main Content */
main {
    flex: 1;
    padding: 4rem 2rem;
    max-width: 1400px;
    margin: 0 auto;
    width: 100%;
}

.systems-grid {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
    gap: 2.5rem;
}

/* Card Styling */
.system-card {
    background-color: var(--card-bg);
    border-radius: 20px;
    padding: 2.5rem 2rem;
    text-align: center;
    text-decoration: none;
    color: var(--text-main);
    box-shadow: var(--card-shadow);
    transition: all 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
    border: 1px solid var(--border-color);
    display: flex;
    flex-direction: column;
    align-items: center;
    justify-content: flex-start;
    position: relative;
    overflow: hidden;
}

.system-card::before {
    content: '';
    position: absolute;
    top: 0;
    left: 0;
    width: 100%;
    height: 6px;
    background: var(--gradient-header);
    opacity: 0;
    transition: opacity 0.3s ease;
}

.system-card:hover {
    transform: translateY(-8px);
    box-shadow: var(--hover-shadow);
}

.system-card:hover::before {
    opacity: 1;
}

/* Icon Styling */
.system-icon {
    width: 80px;
    height: 80px;
    background: var(--gradient-icon);
    border-radius: 50%;
    display: flex;
    align-items: center;
    justify-content: center;
    margin-bottom: 1.5rem;
    transition: transform 0.3s ease, background 0.3s ease;
    color: var(--primary-color);
    font-size: 2rem;
}

.system-card:hover .system-icon {
    transform: scale(1.1) rotate(5deg);
    background: var(--gradient-header);
    color: white;
}

/* Typography in Cards */
.system-card h2 {
    font-family: 'Poppins', sans-serif;
    font-size: 1.5rem;
    font-weight: 600;
    margin-bottom: 0.75rem;
    color: var(--text-main);
    transition: color 0.3s ease;
}

.system-card:hover h2 {
    color: var(--primary-color);
}

.system-card p {
    font-size: 0.95rem;
    color: var(--text-secondary);
    line-height: 1.5;
}

/* Em Breve Card */
.system-card[href="#"] {
    opacity: 0.8;
    background-color: rgba(255, 255, 255, 0.03);
    border: 2px dashed var(--border-color);
    box-shadow: none;
}

.system-card[href="#"]:hover {
    transform: translateY(-3px);
    border-color: var(--primary-color);
    background-color: var(--card-bg);
}

.system-card[href="#"] .system-icon {
    background: rgba(255, 255, 255, 0.05);
    color: var(--text-secondary);
}

.system-card[href="#"] h2 {
    color: var(--text-secondary);
}

/* Footer */
footer {
    background-color: var(--card-bg);
    border-top: 1px solid var(--border-color);
    color: var(--text-secondary);
    text-align: center;
    padding: 2rem;
    margin-top: auto;
}

footer p {
    font-size: 0.9rem;
    opacity: 0.8;
}

/* Responsive */
@media (max-width: 768px) {
    header {
        padding: 2rem 1rem;
    }

    header h1 {
        font-size: 2rem;
    }

    main {
        padding: 2rem 1rem;
    }

    .systems-grid {
        grid-template-columns: 1fr;
    }
}

.footer-link {
    text-decoration: none;
    color: var(--text-secondary);
    transition: color 0.3s ease;
    font-weight: 500;
}

.footer-link:hover {
    color: var(--primary-color);
}