:root {
    --primary: #4f46e5;
    --primary-hover: #6366f1;
    --secondary: #06b6d4;
    --accent: #8b5cf6;

    --bg-dark: #050816;
    --bg-secondary: #0f172a;

    --glass-bg: rgba(15, 23, 42, 0.75);
    --glass-border: rgba(255, 255, 255, 0.08);

    --text-main: #f8fafc;
    --text-muted: #94a3b8;

    --success: #22c55e;
    --danger: #ef4444;

    --shadow-lg: 0 20px 40px rgba(0, 0, 0, 0.35);
    --shadow-sm: 0 8px 20px rgba(0, 0, 0, 0.2);

    --radius: 18px;
}

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

html {
    scroll-behavior: smooth;
}

body {
    font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    color: var(--text-main);

    background:
        radial-gradient(circle at top left,
            rgba(79, 70, 229, 0.25),
            transparent 35%),
        radial-gradient(circle at bottom right,
            rgba(6, 182, 212, 0.18),
            transparent 35%),
        linear-gradient(135deg,
            #050816 0%,
            #0b1120 40%,
            #111827 100%);
}

/* ==========================
   GLOBAL GLASS CARD
========================== */

.glass-card {
    background: var(--glass-bg);
    backdrop-filter: blur(18px);
    -webkit-backdrop-filter: blur(18px);

    border: 1px solid var(--glass-border);
    border-radius: var(--radius);

    box-shadow: var(--shadow-lg);

    transition: all 0.3s ease;
}

.glass-card:hover {
    transform: translateY(-4px);
    border-color: rgba(99, 102, 241, 0.25);
}

/* ==========================
   NAVBAR
========================== */

nav {
    position: sticky;
    top: 0;
    z-index: 1000;

    display: flex;
    justify-content: space-between;
    align-items: center;

    padding: 1.25rem 2rem;

    background: rgba(5, 8, 22, 0.8);
    backdrop-filter: blur(14px);
    -webkit-backdrop-filter: blur(14px);

    border-bottom: 1px solid rgba(255, 255, 255, 0.06);
}

.logo {
    display: flex;
    align-items: center;
    gap: 12px;

    font-size: 1.6rem;
    font-weight: 800;
    letter-spacing: -0.5px;
}

.logo img {
    width: 42px;
    height: 42px;
    object-fit: cover;
    border-radius: 10px;

    border: 1px solid rgba(255,255,255,0.08);
}

.logo span {
    background: linear-gradient(
        135deg,
        var(--primary),
        var(--secondary),
        var(--accent)
    );

    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

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

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

    margin-left: 2rem;

    font-weight: 600;
    transition: all 0.3s ease;
}

.nav-links a:hover {
    color: white;
}

/* ==========================
   MAIN
========================== */

main {
    flex: 1;

    width: 100%;
    max-width: 1200px;

    margin: 0 auto;
    padding: 5rem 2rem;
}

/* ==========================
   HERO
========================== */

.hero {
    text-align: center;
    margin-bottom: 5rem;
}

.hero h1 {
    font-size: clamp(3rem, 7vw, 5.5rem);
    font-weight: 900;
    line-height: 1.1;
    margin-bottom: 1.5rem;

    background: linear-gradient(
        135deg,
        #ffffff,
        #cbd5e1,
        #60a5fa
    );

    -webkit-background-clip: text;
    background-clip: text;
    -webkit-text-fill-color: transparent;
}

.hero p {
    color: var(--text-muted);
    max-width: 700px;

    margin: 0 auto;

    font-size: 1.15rem;
    line-height: 1.8;
}

/* ==========================
   FORMS
========================== */

.form-container {
    max-width: 450px;
    margin: auto;
    padding: 2.5rem;
}

.form-group {
    margin-bottom: 1.5rem;
}

.form-group label {
    display: block;

    margin-bottom: 0.6rem;

    color: #cbd5e1;
    font-size: 0.9rem;
    font-weight: 500;
}

input {
    width: 100%;

    padding: 0.95rem 1rem;

    border-radius: 12px;
    border: 1px solid rgba(255,255,255,0.08);

    background: rgba(255,255,255,0.04);
    color: white;

    outline: none;

    transition: all 0.3s ease;
}

input::placeholder {
    color: #64748b;
}

input:focus {
    border-color: var(--primary);
    box-shadow: 0 0 0 4px rgba(79,70,229,0.2);
}

/* ==========================
   BUTTONS
========================== */

.btn {
    width: 100%;

    border: none;
    cursor: pointer;

    text-decoration: none;
    text-align: center;

    padding: 0.95rem 1.5rem;

    border-radius: 12px;

    font-weight: 700;

    transition: all 0.3s ease;
}

.btn-primary {
    color: white;

    background: linear-gradient(
        135deg,
        var(--primary),
        var(--secondary)
    );

    box-shadow:
        0 10px 30px rgba(79,70,229,0.35);
}

.btn-primary:hover {
    transform: translateY(-3px);

    box-shadow:
        0 18px 35px rgba(79,70,229,0.45);
}

.btn-primary:active {
    transform: translateY(0);
}

/* ==========================
   FOOTER
========================== */

footer {
    padding: 2rem;

    text-align: center;

    color: var(--text-muted);

    border-top: 1px solid rgba(255,255,255,0.06);

    background: rgba(255,255,255,0.02);
}

/* ==========================
   TEST SUITE
========================== */

.test-suite-container {
    margin-top: 3rem;
}

.test-case-block {
    margin-bottom: 2rem;
    padding: 1.75rem;
}

.test-case-header {
    display: flex;
    justify-content: space-between;
    align-items: center;

    margin-bottom: 1rem;
}

pre {
    background: #020617;

    color: #67e8f9;

    padding: 1rem;

    border-radius: 12px;

    overflow-x: auto;

    border: 1px solid rgba(255,255,255,0.05);

    font-size: 0.92rem;
    line-height: 1.6;
}

/* ==========================
   BADGES
========================== */

.badge {
    display: inline-flex;
    align-items: center;

    padding: 0.4rem 0.85rem;

    border-radius: 999px;

    font-size: 0.75rem;
    font-weight: 700;
}

.badge-l1 {
    background: rgba(79,70,229,0.15);
    color: #a5b4fc;
}

.badge-l6 {
    background: rgba(34,197,94,0.15);
    color: #86efac;
}

/* ==========================
   SCROLLBAR
========================== */

::-webkit-scrollbar {
    width: 10px;
}

::-webkit-scrollbar-track {
    background: #0b1120;
}

::-webkit-scrollbar-thumb {
    background: linear-gradient(
        var(--primary),
        var(--secondary)
    );
    border-radius: 50px;
}

/* ==========================
   MOBILE
========================== */

@media (max-width: 768px) {

    nav {
        padding: 1rem;
    }

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

    main {
        padding: 3rem 1.25rem;
    }

    .hero h1 {
        font-size: 2.8rem;
    }

    .hero p {
        font-size: 1rem;
    }

    .form-container {
        padding: 1.5rem;
    }

    .test-case-header {
        flex-direction: column;
        gap: 0.75rem;
        align-items: flex-start;
    }
}