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

:root {
    --bg-dark: #0a0a0f;
    --text-primary: #f8fafc;
    --text-secondary: #94a3b8;
    --accent-blue: #3b82f6;
    --accent-red: #ef4444;
    --border: #1e293b;
}

body {
    font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    background: var(--bg-dark);
    color: var(--text-primary);
    line-height: 1.6;
    -webkit-font-smoothing: antialiased;
    -moz-osx-font-smoothing: grayscale;
}

/* Hero Background */
.hero-background {
    position: fixed;
    top: 0;
    left: 0;
    width: 100%;
    height: 100vh;
    background:
        linear-gradient(
            180deg,
            rgba(10, 10, 15, 0.7) 0%,
            rgba(10, 10, 15, 0.9) 50%,
            rgba(10, 10, 15, 1) 100%
        ),
        url('https://images.unsplash.com/photo-1555991855-1f3319bc8e8a?auto=format&fit=crop&w=2000&q=80');
    background-size: cover;
    background-position: center;
    z-index: 0;
    opacity: 0.4;
}

/* Container */
.container {
    max-width: 900px;
    margin: 0 auto;
    padding: 3rem 2rem;
    position: relative;
    z-index: 1;
    min-height: 100vh;
    display: flex;
    flex-direction: column;
}

main {
    flex: 1;
    display: flex;
    flex-direction: column;
    justify-content: center;
    padding: 4rem 0;
}

/* Hero Content */
.hero-content {
    margin-bottom: 6rem;
    text-align: center;
}

.site-title {
    font-family: 'IBM Plex Serif', Georgia, serif;
    font-size: clamp(3.5rem, 10vw, 6rem);
    font-weight: 600;
    line-height: 1;
    margin-bottom: 2rem;
    color: var(--text-primary);
    letter-spacing: -0.03em;
}

.tagline {
    font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: clamp(1.25rem, 3vw, 1.5rem);
    font-weight: 400;
    line-height: 1.5;
    color: var(--text-secondary);
    margin-bottom: 2rem;
    max-width: 700px;
    margin-left: auto;
    margin-right: auto;
}

.description {
    font-size: clamp(1rem, 2vw, 1.1rem);
    line-height: 1.7;
    color: var(--text-secondary);
    max-width: 600px;
    margin: 0 auto;
}

/* Form Section */
.form-section {
    max-width: 600px;
    margin: 0 auto;
}

.form-title {
    font-family: 'IBM Plex Sans', -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
    font-size: clamp(1.5rem, 4vw, 1.75rem);
    font-weight: 600;
    margin-bottom: 2rem;
    text-align: center;
    color: var(--text-primary);
    letter-spacing: -0.01em;
}

.signup-form {
    display: flex;
    flex-direction: column;
    gap: 1rem;
}

.form-row {
    display: flex;
    gap: 0.75rem;
}

.form-row input {
    flex: 1;
    padding: 1rem 1.25rem;
    font-size: 1rem;
    font-family: inherit;
    background: rgba(255, 255, 255, 0.05);
    border: 1px solid var(--border);
    border-radius: 8px;
    color: var(--text-primary);
    transition: all 0.2s ease;
}

.form-row input:focus {
    outline: none;
    border-color: var(--accent-blue);
    background: rgba(255, 255, 255, 0.08);
    box-shadow: 0 0 0 3px rgba(59, 130, 246, 0.1);
}

.form-row input::placeholder {
    color: #64748b;
}

.submit-btn {
    padding: 1rem 3rem;
    font-size: 1rem;
    font-weight: 600;
    font-family: inherit;
    background: linear-gradient(135deg, var(--accent-blue) 0%, var(--accent-red) 100%);
    color: white;
    border: none;
    border-radius: 8px;
    cursor: pointer;
    transition: all 0.2s ease;
    align-self: center;
    margin-top: 0.5rem;
}

.submit-btn:hover {
    transform: translateY(-2px);
    box-shadow: 0 10px 30px -5px rgba(59, 130, 246, 0.4);
}

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

.submit-btn:disabled {
    opacity: 0.6;
    cursor: not-allowed;
}

.form-message {
    padding: 1rem;
    border-radius: 8px;
    text-align: center;
    font-size: 0.95rem;
    display: none;
    margin-top: 0.5rem;
}

.form-message.success {
    display: block;
    background: rgba(34, 197, 94, 0.1);
    border: 1px solid rgba(34, 197, 94, 0.3);
    color: #86efac;
}

.form-message.error {
    display: block;
    background: rgba(239, 68, 68, 0.1);
    border: 1px solid rgba(239, 68, 68, 0.3);
    color: #fca5a5;
}

/* Footer */
footer {
    text-align: center;
    padding: 3rem 0 2rem;
    margin-top: auto;
    color: var(--text-secondary);
    font-size: 0.85rem;
}

/* Responsive Design */
@media (max-width: 768px) {
    .container {
        padding: 2rem 1.5rem;
    }

    main {
        padding: 2rem 0;
    }

    .hero-content {
        margin-bottom: 4rem;
    }

    .form-row {
        flex-direction: column;
        gap: 0.75rem;
    }
}

@media (max-width: 480px) {
    .container {
        padding: 1.5rem 1rem;
    }

    .hero-content {
        margin-bottom: 3rem;
    }

    .submit-btn {
        width: 100%;
    }
}

/* Selection */
::selection {
    background: var(--accent-blue);
    color: white;
}

::-moz-selection {
    background: var(--accent-blue);
    color: white;
}