If the current state of the stock market is making you antsy, you're not alone. Investors are taking note of warning signs that a stock market correction or even crash could be imminent.

Rather than fret about what the market may have in store, it's a smart strategy to use this time to focus on building your nest egg and fortifying your portfolio for the future. Market fluctuations are a normal part of investing, and the reality for long-term investors is that these ups and downs can have a short-term effect on your portfolio's performance.

By focusing on quality stocks with a history of stable returns and promising growth runways, you can minimize the potential effect of volatility on your holdings while locking in long-term returns. On that note, if you want your portfolio to both survive and thrive through the next stock market crash or correction, here are two top-notch companies to consider buying right now.

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1. Amazon

It's an oldie but a goodie. Over the past year, Amazon (AMZN 0.83%) has built on its track record of stellar balance sheet growth. The company keeps expanding its vast collection of businesses that span from e-commerce to cloud computing and artificial intelligence all the way to healthcare. The behemoth's shares have shot up 35% over the past year alone.

In 2020, Amazon grew its net sales by a whopping 38%. Its net income surged to $21.3 billion, a nearly 84% spike from the $11.6 billion in net income the company reported in 2019. Amazon continued to grow its impressive cash position in 2020, with operating cash flow spiking 72% over the 12-month period.

Amazon started 2021 on an equally high note. Its first-quarter net sales represented a 44% increase from the year-ago period, and its net income shot up more than 220% year over year. The company's Amazon Web Services (AWS) business is a key catalyst for its ongoing balance sheet growth -- generating 32% year-over-year sales growth in the first quarter. During the first quarter, Amazon also launched "the next generation of Echo Buds," opened new Amazon Fresh locations in the U.S. and London, and hit 200 million Amazon Prime members.

Amazon's continued resilience in the face of volatility can be attributed to its optionality and the uninterrupted demand its businesses attract. Case in point: AWS has become the world's top cloud infrastructure provider. According to Statista, "Amazon's market share in the worldwide cloud infrastructure market amounted to 32 percent in the fourth quarter of 2020, still exceeding the combined market share of its two largest competitors, Microsoft and Google."

Amazon also continues to dominate in e-commerce, with Statista estimating that the company "will account for 50 percent of the entire e-commerce retail market's gross merchandise volume" as of this year.

Amazon's run as a compelling growth play is far from over, and this has proven to be truer than ever throughout the past year. If you want to stabilize your portfolio for whatever market headwinds lie around the corner, Amazon is a gem to buy and hold for decades to come.

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2. Innovative Industrial Properties

The U.S. cannabis industry is known for experiencing a mixture of headwinds and tailwinds, but plenty of top stocks in this sector have capitalized on expanding market opportunities and new waves of state by state legalization. Innovative Industrial Properties (IIPR 0.23%) is one of my favorite high-caliber pot plays that you can buy and hold for long-term sustainable returns.

Innovative Industrial Properties is a real estate investment trust (REIT) that operates solely in the medical-use cannabis space. How exactly does this work? Innovative Industrial Properties owns a broad portfolio of greenhouses and industrial properties in states like Arizona, California, Florida, Illinois, and Massachusetts. The company leases these facilities to licensed growers of medical cannabis.

Another way Innovative Industrial Properties differentiates itself from the average pot stock is that it pays a dividend -- and a robust dividend to boot. Its dividend yields 3% based on current share prices, and the company just announced a 32% year-over-year boost to its quarterly payout on March 15.

Innovative Industrial Properties saw its revenue shoot up 162% in the full-year 2020. In addition to its impressive top-line growth, the company's net income rose by an incredible 191% year over year. And in the first quarter of 2021, its revenue and net income spiked by 103% and 122% respectively.

As medical-use cannabis legalization expands nationwide, Innovative Industrial Properties has plenty of market share left to pursue in this highly profitable side of the marijuana industry. In fact, Alabama passed a law this week to open up a medical cannabis market. With this pot REIT, investors can reap the benefits of this growing market in the form of continued dividend growth and share price gains.