:root {
    /* Color Palette - HSL (Hue, Saturation, Lightness) */
    /* Primary (Aurora Cyan) */
    --primary-h: 180;
    --primary-s: 100%;
    --primary-l: 50%;
    --primary: hsl(var(--primary-h), var(--primary-s), var(--primary-l));

    /* Secondary (Aurora Purple) */
    --secondary-h: 270;
    --secondary-s: 100%;
    --secondary-l: 65%;
    --secondary: hsl(var(--secondary-h), var(--secondary-s), var(--secondary-l));

    /* Backgrounds (Dark Slate) */
    --bg-h: 222;
    --bg-s: 47%;
    --bg-l: 7%;
    /* Very Dark */
    --bg-color: hsl(var(--bg-h), var(--bg-s), var(--bg-l));

    --card-bg-h: 217;
    --card-bg-s: 33%;
    --card-bg-l: 15%;
    --card-bg: hsl(var(--card-bg-h), var(--card-bg-s), var(--card-bg-l));

    /* Text */
    --text-main: hsl(210, 40%, 98%);
    --text-muted: hsl(215, 20%, 65%);
    --text-accent: var(--primary);

    /* Borders */
    --border-color: hsl(215, 25%, 25%);

    /* Typography */
    --font-heading: 'Outfit', system-ui, sans-serif;
    --font-body: 'Inter', system-ui, sans-serif;

    /* Spacing & Radii */
    --radius-md: 0.75rem;
    --radius-lg: 1rem;
    --header-height: 4rem;

    /* Effects */
    --shadow-sm: 0 1px 2px 0 rgb(0 0 0 / 0.05);
    --shadow-md: 0 4px 6px -1px rgb(0 0 0 / 0.2), 0 2px 4px -2px rgb(0 0 0 / 0.1);
    --shadow-glow: 0 0 15px hsla(var(--primary-h), var(--primary-s), 50%, 0.15);
}

*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    background-color: var(--bg-color);
    color: var(--text-main);
    font-family: var(--font-body);
    margin: 0;
    line-height: 1.6;
    display: flex;
    flex-direction: column;
    min-height: 100vh;
    -webkit-font-smoothing: antialiased;
}

h1,
h2,
h3,
h4,
h5,
h6 {
    font-family: var(--font-heading);
    margin-top: 0;
    line-height: 1.2;
    color: var(--text-main);
}

h1 {
    font-weight: 700;
}

/* Header */
header {
    background: rgba(15, 23, 42, 0.8);
    /* Semi-transparent */
    backdrop-filter: blur(12px);
    -webkit-backdrop-filter: blur(12px);
    border-bottom: 1px solid var(--border-color);
    height: var(--header-height);
    padding: 0 2rem;
    display: flex;
    justify-content: space-between;
    align-items: center;
    position: sticky;
    top: 0;
    z-index: 50;
}

header h1 {
    font-size: 1.5rem;
    margin: 0;
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
    letter-spacing: -0.02em;
}

header nav a {
    color: var(--text-muted);
    text-decoration: none;
    font-weight: 500;
    margin-left: 1.5rem;
    transition: color 0.15s ease;
    font-size: 0.95rem;
}

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

/* Main Layout */
main {
    flex: 1;
    padding: 2rem;
    max-width: 1200px;
    margin: 0 auto;
    width: 100%;
}

/* Card Component */
.card {
    background-color: var(--card-bg);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-lg);
    padding: 2rem;
    margin-bottom: 1.5rem;
    box-shadow: var(--shadow-md);
    position: relative;
    overflow: hidden;
    transition: transform 0.2s ease, box-shadow 0.2s ease, border-color 0.2s ease;
}

.card:hover {
    transform: translateY(-2px);
    box-shadow: var(--shadow-glow), var(--shadow-md);
    border-color: hsla(var(--primary-h), var(--primary-s), 50%, 0.3);
}

.card h2 {
    font-size: 1.25rem;
    margin-bottom: 1rem;
    color: var(--text-main);
    display: flex;
    align-items: center;
    gap: 0.5rem;
}

.card p {
    color: var(--text-muted);
    margin-bottom: 0;
    font-size: 0.95rem;
}

/* Links */
a {
    color: var(--primary);
    text-decoration: none;
    transition: opacity 0.2s;
}

a:hover {
    opacity: 0.8;
}

/* Buttons (Future Proofing) */
.btn {
    display: inline-flex;
    align-items: center;
    justify-content: center;
    padding: 0.5rem 1rem;
    border-radius: var(--radius-md);
    font-weight: 600;
    font-family: var(--font-heading);
    cursor: pointer;
    transition: all 0.2s ease;
    border: none;
    font-size: 0.9rem;
    text-decoration: none;
}

.btn-primary {
    background: linear-gradient(135deg, var(--primary), hsl(var(--primary-h), 90%, 45%));
    color: #000;
    /* Contrast text on Cyan */
    box-shadow: 0 4px 6px -1px hsla(var(--primary-h), var(--primary-s), 50%, 0.2);
}

.btn-primary:hover {
    filter: brightness(1.1);
    box-shadow: 0 6px 8px -1px hsla(var(--primary-h), var(--primary-s), 50%, 0.3);
}

/* Forms & Inputs */
input[type="text"],
input[type="email"],
input[type="password"],
textarea,
select {
    width: 100%;
    padding: 0.75rem 1rem;
    background-color: rgba(15, 23, 42, 0.5);
    border: 1px solid var(--border-color);
    border-radius: var(--radius-md);
    color: var(--text-main);
    font-family: var(--font-body);
    font-size: 0.95rem;
    transition: all 0.2s;
}

input:focus,
textarea:focus,
select:focus {
    outline: none;
    border-color: var(--primary);
    box-shadow: 0 0 0 2px hsla(var(--primary-h), var(--primary-s), 50%, 0.2);
    background-color: rgba(15, 23, 42, 0.8);
}

/* Tables */
table {
    width: 100%;
    border-collapse: collapse;
    margin: 1rem 0;
}

th {
    text-align: left;
    padding: 1rem;
    background-color: rgba(15, 23, 42, 0.5);
    color: var(--text-muted);
    font-weight: 600;
    font-size: 0.85rem;
    text-transform: uppercase;
    letter-spacing: 0.05em;
    border-bottom: 1px solid var(--border-color);
}

td {
    padding: 1rem;
    border-bottom: 1px solid #1e293b;
    /* Fallback or specific border */
    border-bottom: 1px solid rgba(255, 255, 255, 0.05);
    color: var(--text-main);
}

tr:last-child td {
    border-bottom: none;
}

tr:hover td {
    background-color: rgba(255, 255, 255, 0.02);
}

/* Footer */
footer {
    padding: 2rem;
    text-align: center;
    color: var(--text-muted);
    font-size: 0.875rem;
    border-top: 1px solid var(--border-color);
    background: var(--bg-color);
}

/* Utilities */
.text-gradient {
    background: linear-gradient(135deg, var(--primary), var(--secondary));
    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

/* Animations & Micro-Interactions */
@keyframes fadeIn {
    from {
        opacity: 0;
        transform: translateY(10px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

@keyframes slideUp {
    from {
        opacity: 0;
        transform: translateY(20px);
    }

    to {
        opacity: 1;
        transform: translateY(0);
    }
}

/* Entry Animations */
.fade-in {
    animation: fadeIn 0.4s ease-out forwards;
}

/* Stagger animations for children using nth-child */
main>* {
    opacity: 0;
    /* Initially hidden */
    animation: slideUp 0.5s ease-out forwards;
}

main>*:nth-child(1) {
    animation-delay: 0.1s;
}

main>*:nth-child(2) {
    animation-delay: 0.2s;
}

main>*:nth-child(3) {
    animation-delay: 0.3s;
}

main>*:nth-child(4) {
    animation-delay: 0.4s;
}

/* Dynamic Background */
body::before {
    content: '';
    position: fixed;
    top: 0;
    left: 0;
    width: 100vw;
    height: 100vh;
    background:
        radial-gradient(circle at 15% 50%, hsla(var(--primary-h), var(--primary-s), var(--primary-l), 0.08), transparent 25%),
        radial-gradient(circle at 85% 30%, hsla(var(--secondary-h), var(--secondary-s), var(--secondary-l), 0.08), transparent 25%);
    z-index: -1;
    pointer-events: none;
}

/* Link Interactions */
a {
    position: relative;
    transition: color 0.2s ease, opacity 0.2s ease;
}

header nav a::after {
    content: '';
    position: absolute;
    bottom: -4px;
    left: 0;
    width: 0%;
    height: 2px;
    background: var(--primary);
    transition: width 0.3s cubic-bezier(0.4, 0, 0.2, 1);
}

header nav a:hover::after {
    width: 100%;
}

/* Accessibility: Reduced Motion */
@media (prefers-reduced-motion: reduce) {

    *,
    *::before,
    *::after {
        animation-duration: 0.01ms !important;
        animation-iteration-count: 1 !important;
        transition-duration: 0.01ms !important;
        scroll-behavior: auto !important;
    }
}

/* Mobile Responsiveness */
@media (max-width: 768px) {
    :root {
        --header-height: 3.5rem;
        /* Compact header on mobile */
    }

    body {
        font-size: 14px;
        /* Slightly smaller base font */
    }

    /* Layout Adjustments */
    header {
        padding: 0 1rem;
    }

    header nav a {
        margin-left: 1rem;
        font-size: 0.9rem;
    }

    main {
        padding: 1rem;
        width: 100%;
        max-width: 100%;
    }

    /* Typography Scaling */
    h1 {
        font-size: 1.75rem;
    }

    h2 {
        font-size: 1.5rem;
    }

    h3 {
        font-size: 1.25rem;
    }

    /* Card Adjustments */
    .card {
        padding: 1.25rem;
        border-radius: var(--radius-md);
        /* Slightly smaller radius */
    }

    /* Stack flex containers if needed (general util) */
    .flex-col-mobile {
        flex-direction: column !important;
    }

    /* Touch Targets */
    .btn,
    a,
    input,
    select {
        min-height: 44px;
        /* Compliance with touch target guidelines */
    }

    /* Horizontal scroll for wide tables */
    .table-container {
        overflow-x: auto;
        -webkit-overflow-scrolling: touch;
        margin-left: -1rem;
        margin-right: -1rem;
        padding-left: 1rem;
        padding-right: 1rem;
    }
}