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

:root {
    --bg: #000000;
    --bg-subtle: #0a0a0a;
    --surface: rgba(255, 255, 255, 0.05);
    --border: rgba(255, 255, 255, 0.12);
    --border-focus: rgba(255, 255, 255, 0.4);
    --text: #ffffff;
    --text-muted: #888888;
}

body {
    font-family: 'Inter', -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;
    overflow: hidden;
    position: relative;
}

/* Starfield */
.stars {
    position: fixed;
    inset: 0;
    pointer-events: none;
    z-index: 0;
}

.star {
    position: absolute;
    background: #ffffff;
    border-radius: 50%;
    opacity: 0;
    animation: twinkle ease-in-out infinite alternate;
}

@keyframes twinkle {
    from { opacity: 0.05; }
    to { opacity: 0.5; }
}

/* Layout */
.container {
    position: relative;
    z-index: 1;
    text-align: center;
    padding: 40px 24px;
    max-width: 440px;
    width: 100%;
}

/* Logo */
.logo-img {
    width: 96px;
    height: 96px;
    margin-bottom: 20px;
    border-radius: 20px;
}

/* Branding */
.logo-text {
    font-size: 3rem;
    font-weight: 800;
    letter-spacing: 0.18em;
    color: var(--text);
    margin-bottom: 14px;
}

.tagline {
    font-size: 1.1rem;
    font-weight: 400;
    color: var(--text-muted);
    margin-bottom: 24px;
}

.divider {
    width: 48px;
    height: 1px;
    background: var(--border-focus);
    margin: 0 auto 24px;
}

.subtitle {
    font-size: 0.95rem;
    font-weight: 500;
    color: var(--text);
    margin-bottom: 28px;
}

/* Toggle */
.toggle-group {
    display: flex;
    background: var(--surface);
    border: 1px solid var(--border);
    border-radius: 10px;
    overflow: hidden;
}

.toggle-btn {
    flex: 1;
    padding: 10px;
    font-size: 0.9rem;
    font-weight: 600;
    font-family: inherit;
    border: none;
    background: transparent;
    color: var(--text-muted);
    cursor: pointer;
    transition: background 0.2s, color 0.2s;
}

.toggle-btn.active {
    background: #ffffff;
    color: #000000;
}

/* Form */
.signup-form {
    display: flex;
    flex-direction: column;
    gap: 12px;
}

.form-group input {
    width: 100%;
    padding: 14px 16px;
    font-size: 1rem;
    font-family: inherit;
    border: 1px solid var(--border);
    border-radius: 10px;
    background: var(--surface);
    color: var(--text);
    outline: none;
    transition: border-color 0.2s, box-shadow 0.2s;
}

.form-group input::placeholder {
    color: var(--text-muted);
}

.form-group input:focus {
    border-color: var(--border-focus);
    box-shadow: 0 0 0 3px rgba(255, 255, 255, 0.06);
}

button[type="submit"] {
    width: 100%;
    padding: 14px;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    border: none;
    border-radius: 10px;
    background: #ffffff;
    color: #000000;
    cursor: pointer;
    transition: background 0.2s, transform 0.15s, box-shadow 0.2s;
    margin-top: 2px;
}

button[type="submit"]:hover {
    background: #e0e0e0;
    transform: translateY(-1px);
    box-shadow: 0 4px 16px rgba(255, 255, 255, 0.08);
}

button[type="submit"]:active {
    transform: translateY(0);
}

button[type="submit"]:disabled {
    opacity: 0.5;
    cursor: not-allowed;
    transform: none;
}

/* Messages */
.success-message {
    margin-top: 24px;
    padding: 16px;
    border-radius: 10px;
    background: rgba(255, 255, 255, 0.06);
    border: 1px solid rgba(255, 255, 255, 0.2);
    color: var(--text);
    font-weight: 500;
}

.error-message {
    margin-top: 14px;
    padding: 12px;
    border-radius: 10px;
    background: rgba(255, 68, 68, 0.1);
    border: 1px solid rgba(255, 68, 68, 0.25);
    color: #ff6b6b;
    font-size: 0.9rem;
}

.hidden {
    display: none !important;
}

/* Footer */
footer {
    margin-top: 48px;
}

.company-name {
    font-size: 0.75rem;
    color: var(--text-muted);
    letter-spacing: 0.06em;
}

/* Responsive */
@media (max-width: 480px) {
    .logo-text {
        font-size: 2.2rem;
    }

    .logo-img {
        width: 72px;
        height: 72px;
    }

    .tagline {
        font-size: 1rem;
    }

    .container {
        padding: 32px 20px;
    }
}