:root {
    --primary: #6366f1;
    --primary-dark: #4f46e5;
    --bg: #f4f4f5;
    --card-bg: #ffffff;
    --text: #18181b;
    --text-muted: #71717a;
    --text-light: #a1a1aa;
    --success: #22c55e;
    --error: #ef4444;
    --warning: #f59e0b;
    --border: #e4e4e7;
    --header-bg: #1a1a2e;
}

@media (prefers-color-scheme: dark) {
    :root {
        --bg: #09090b;
        --card-bg: #18181b;
        --text: #fafafa;
        --text-muted: #a1a1aa;
        --text-light: #71717a;
        --border: #27272a;
        --header-bg: #0f0f23;
    }
}

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

body {
    font-family: -apple-system, BlinkMacSystemFont, 'Segoe UI', Roboto, sans-serif;
    background: var(--bg);
    color: var(--text);
    min-height: 100vh;
    display: flex;
    align-items: center;
    justify-content: center;
    padding: 20px;
}

.container {
    width: 100%;
    max-width: 480px;
}

.card {
    background: var(--card-bg);
    border-radius: 16px;
    overflow: hidden;
    box-shadow: 0 4px 24px rgba(0,0,0,0.08);
}

.card-header {
    background: var(--header-bg);
    padding: 32px;
    text-align: center;
}

.card-header h1 {
    color: #ffffff;
    font-size: 22px;
    font-weight: 600;
}

.card-body {
    padding: 40px 32px;
}

.card-footer {
    padding: 20px 32px;
    text-align: center;
    border-top: 1px solid var(--border);
}

.card-footer p {
    color: var(--text-light);
    font-size: 12px;
}

/* States */
.state { display: none; text-align: center; }
.state.active { display: block; }

.icon {
    font-size: 64px;
    margin-bottom: 16px;
}

.state h2 {
    font-size: 20px;
    margin-bottom: 12px;
    color: var(--text);
}

.state p {
    color: var(--text-muted);
    font-size: 15px;
    line-height: 1.6;
    margin-bottom: 16px;
}

/* Loading spinner */
.spinner {
    width: 48px;
    height: 48px;
    border: 4px solid var(--border);
    border-top-color: var(--primary);
    border-radius: 50%;
    animation: spin 0.8s linear infinite;
    margin: 0 auto 16px;
}

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

/* Buttons */
.btn {
    display: inline-block;
    padding: 12px 28px;
    border-radius: 8px;
    font-size: 15px;
    font-weight: 600;
    text-decoration: none;
    cursor: pointer;
    border: none;
    transition: background 0.2s;
}

.btn-primary {
    background: var(--primary);
    color: #ffffff;
}

.btn-primary:hover {
    background: var(--primary-dark);
}

.btn-outline {
    background: transparent;
    color: var(--primary);
    border: 2px solid var(--primary);
}

.btn-outline:hover {
    background: var(--primary);
    color: #ffffff;
}

/* Form */
.form-group {
    margin-bottom: 20px;
    text-align: left;
}

.form-group label {
    display: block;
    font-size: 14px;
    font-weight: 500;
    margin-bottom: 6px;
    color: var(--text);
}

.form-group input {
    width: 100%;
    padding: 12px 16px;
    border: 2px solid var(--border);
    border-radius: 8px;
    font-size: 15px;
    background: var(--card-bg);
    color: var(--text);
    transition: border-color 0.2s;
}

.form-group input:focus {
    outline: none;
    border-color: var(--primary);
}

.requirements {
    text-align: left;
    margin-bottom: 20px;
}

.requirements p {
    font-size: 13px;
    color: var(--text-muted);
    margin-bottom: 4px;
}

.requirements .met { color: var(--success); }
.requirements .unmet { color: var(--text-light); }

.error-text {
    color: var(--error);
    font-size: 13px;
    margin-top: 4px;
}

.success-text {
    color: var(--success);
}