:root {
    /* Cyber Dark Palette */
    --bg-dark: #121212;
    --bg-card: #1e1e1e;
    --bg-input: #2a2a2a;
    
    /* Neons */
    --neon-cyan: #00e5ff;
    --neon-purple: #bb86fc;
    --neon-error: #cf6679;
    
    /* Text */
    --text-primary: #ffffff;
    --text-secondary: #a0a0a0;
    
    /* Spacing */
    --radius: 12px;
    --gap: 16px;
}

* {
    box-sizing: border-box;
    margin: 0;
    padding: 0;
    -webkit-tap-highlight-color: transparent;
}

body {
    background-color: var(--bg-dark);
    color: var(--text-primary);
    font-family: 'Inter', -apple-system, BlinkMacSystemFont, sans-serif;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
    overflow-x: hidden;
}

/* Typography */
h1, h2, h3 {
    font-weight: 700;
    letter-spacing: -0.5px;
}

a {
    text-decoration: none;
    color: var(--neon-cyan);
}

/* Utilities */
.container {
    width: 100%;
    max-width: 480px; /* Mobile First logic */
    margin: 0 auto;
    padding: 20px;
    flex: 1;
    display: flex;
    flex-direction: column;
}

.center-xy {
    justify-content: center;
    align-items: center;
    text-align: center;
}

/* Forms & Inputs */
input {
    width: 100%;
    padding: 16px;
    background: var(--bg-input);
    border: 2px solid transparent;
    border-radius: var(--radius);
    color: white;
    font-size: 16px;
    outline: none;
    transition: 0.3s ease;
}

input:focus {
    border-color: var(--neon-cyan);
    box-shadow: 0 0 15px rgba(0, 229, 255, 0.2);
}

/* Buttons */
.btn {
    width: 100%;
    padding: 16px;
    background: var(--neon-cyan);
    color: #000;
    font-weight: 800;
    font-size: 16px;
    border: none;
    border-radius: var(--radius);
    cursor: pointer;
    text-transform: uppercase;
    letter-spacing: 1px;
    transition: transform 0.2s, box-shadow 0.2s;
}

.btn:active {
    transform: scale(0.96);
}

.btn:hover {
    box-shadow: 0 0 20px rgba(0, 229, 255, 0.4);
}

/* Cards */
.card {
    background: var(--bg-card);
    border-radius: var(--radius);
    padding: 16px;
    box-shadow: 0 4px 6px rgba(0,0,0,0.3);
    border: 1px solid rgba(255,255,255,0.05);
}

/* Loader */
.spinner {
    width: 50px;
    height: 50px;
    border: 3px solid rgba(255,255,255,0.1);
    border-top-color: var(--neon-cyan);
    border-radius: 50%;
    animation: spin 1s linear infinite;
    margin-bottom: 20px;
}

@keyframes spin { to { transform: rotate(360deg); } }

/* Logo Text */
.logo {
    font-size: 2rem;
    background: linear-gradient(45deg, var(--neon-cyan), var(--neon-purple));
    -webkit-background-clip: text;
    -webkit-text-fill-color: transparent;
    margin-bottom: 40px;
}