body {
    margin: 0;
    font-family: "Inter", Arial, sans-serif;
    line-height: 1.7;
    color: #222;
    background: #fff;
}

.container {
    max-width: 880px;
    margin: 0 auto;
    padding: 40px 20px;
}

h1, h2, h3, h4 {
    margin-top: 0;
    font-weight: 600;
}

p {
    max-width: 800px;
}

.hero {
    background: #f7f9fb;
    padding: 100px 20px;
    text-align: center;
    border-bottom: 1px solid #e5e5e5;
}

.hero h1 {
    font-size: 34px;
    margin-bottom: 10px;
}

.hero h2 {
    font-size: 24px;
    margin-bottom: 20px;
    color: #444;
}

.tagline {
    max-width: 760px;
    margin: 0 auto 30px;
    font-size: 18px;
    color: #555;
}

.btn {
    display: inline-block;
    padding: 12px 26px;
    margin: 5px;
    text-decoration: none;
    border-radius: 6px;
    font-weight: 500;
    transition: 0.25s ease;
}

.btn.primary {
    background: #1a73e8;
    color: #fff;
}

.btn.primary:hover {
    background: #166ad1;
}

.btn.secondary {
    background: #e6e6e6;
    color: #333;
}

.btn.large {
    padding: 16px 32px;
    font-size: 18px;
}

.section {
    padding: 60px 20px;
}

.section.light {
    background: #fafafa;
    border-top: 1px solid #eee;
    border-bottom: 1px solid #eee;
}

.service-challenge, .service-box {
    background: #ffffff;
    padding: 30px;
    border-radius: 8px;
    margin-top: 30px;
    transition: 0.25s ease;
}

.service-challenge:hover,
.service-box:hover {
    box-shadow: 0 4px 14px rgba(0,0,0,0.04);
}

.credentials-list {
    list-style: none;
    padding-left: 0;
}

.credentials-list li {
    margin-bottom: 25px;
    line-height: 1.6;
}

.contact-info {
    line-height: 1.7;

}

#contact p {
    max-width: 880px;  /* ขยายให้กว้างขึ้น */
}

.text-center {
    text-align: center;
}

.footer {
    text-align: center;
    padding: 20px;
    background: #f7f9fb;
    color: #666;
    font-size: 14px;
}

.center {
    display: block;
    text-align: center;
    margin: 30px auto 0;
    max-width: 600px; /* ให้อ่านง่าย */
}