:root {
    --color-primary: #6366f1;
    --color-primary-hover: #5558e6;
    --color-primary-light: rgba(99, 102, 241, 0.12);
    --color-primary-glow: rgba(99, 102, 241, 0.25);
    --color-dark: #0a0a0b;
    --color-dark-elevated: #111113;
    --color-dark-card: #161618;
    --color-dark-border: #232326;
    --color-dark-border-hover: #3a3a3f;
    --color-text-primary: #fafafa;
    --color-text-secondary: #a1a1aa;
    --color-text-muted: #52525b;
    --font-family: 'Cairo', -apple-system, BlinkMacSystemFont, sans-serif;
    --radius-sm: 8px;
    --radius-md: 12px;
    --radius-lg: 16px;
    --duration-normal: 250ms;
    --ease-spring: cubic-bezier(0.34, 1.56, 0.64, 1);
    --ease-smooth: cubic-bezier(0.4, 0, 0.2, 1);
}

.landing-header {
    background: rgba(10, 10, 11, 0.85);
    backdrop-filter: blur(24px);
    -webkit-backdrop-filter: blur(24px);
    padding: 12px 24px;
    width: 100%;
    display: flex;
    justify-content: space-between;
    align-items: center;
    border-bottom: 1px solid rgba(255, 255, 255, 0.04);
    position: fixed;
    top: 0;
    z-index: 1000;
    transition: all var(--duration-normal) var(--ease-smooth);
}

.landing-header.scrolled {
    background: rgba(10, 10, 11, 0.95);
    border-bottom-color: var(--color-dark-border);
}

.logo-link {
    display: flex;
    align-items: center;
    text-decoration: none;
    color: inherit;
    cursor: pointer;
}

.logo-link:hover {
    opacity: 0.9;
}

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

.logo-img {
    width: 36px;
    height: 36px;
    object-fit: contain;
    border-radius: var(--radius-sm);
    transition: transform var(--duration-normal) var(--ease-spring);
}

.logo-link:hover .logo-img {
    transform: scale(1.08);
}

.logo-text {
    font-size: 1.125rem;
    font-weight: 700;
    color: var(--color-text-primary);
    letter-spacing: -0.01em;
}

.auth-buttons {
    display: flex;
    gap: 10px;
}

.btn {
    padding: 8px 18px;
    border-radius: var(--radius-md);
    text-decoration: none;
    font-weight: 600;
    transition: all var(--duration-normal) var(--ease-spring);
    font-size: 0.85rem;
    cursor: pointer;
    font-family: var(--font-family);
    display: inline-flex;
    align-items: center;
    justify-content: center;
    gap: 8px;
    white-space: nowrap;
    border: none;
}

.btn-primary {
    background: linear-gradient(135deg, #6366f1 0%, #8b5cf6 50%, #a78bfa 100%);
    color: white;
    box-shadow: 0 4px 15px rgba(99, 102, 241, 0.3);
}

.btn-primary:hover {
    transform: translateY(-2px);
    box-shadow: 0 6px 20px rgba(99, 102, 241, 0.4);
}

.btn-ghost {
    background: transparent;
    color: var(--color-text-secondary);
    border: 1px solid var(--color-dark-border);
}

.btn-ghost:hover {
    background: var(--color-dark-elevated);
    border-color: var(--color-dark-border-hover);
    color: var(--color-text-primary);
    transform: translateY(-2px);
}

@media (max-width: 768px) {
    .landing-header {
        padding: 10px 16px;
    }
    .logo-container {
        gap: 8px;
    }
    .logo-img {
        width: 30px;
        height: 30px;
    }
    .logo-text {
        font-size: 1rem;
    }
    .auth-buttons {
        gap: 8px;
    }
    .btn {
        padding: 6px 12px;
        font-size: 0.8rem;
    }
}

@media (max-width: 400px) {
    .landing-header {
        padding: 8px 12px;
    }
    .logo-img {
        width: 26px;
        height: 26px;
    }
    .logo-text {
        font-size: 0.875rem;
    }
    .btn {
        padding: 5px 8px;
        font-size: 0.75rem;
        border-radius: 6px;
    }
}