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

body {
    font-family: "Microsoft YaHei", Arial, sans-serif;
    line-height: 1.6;
    color: #333;
    background: #f8f9fb;
}

header {
    background: linear-gradient(135deg, #2563eb, #22c55e);
    color: white;
    padding: 32px 20px;
    text-align: center;
}

header h1 {
    margin-bottom: 12px;
    font-size: 2.4rem;
}

header p {
    font-size: 1rem;
    max-width: 660px;
    margin: 0 auto;
}

nav {
    display: flex;
    justify-content: center;
    gap: 12px;
    flex-wrap: wrap;
    margin-top: 20px;
}

nav a {
    color: white;
    text-decoration: none;
    padding: 10px 18px;
    border: 1px solid rgba(255,255,255,0.5);
    border-radius: 999px;
    transition: background 0.2s ease;
}

nav a:hover {
    background: rgba(255,255,255,0.18);
}

main {
    max-width: 1080px;
    margin: 0 auto;
    padding: 28px 20px 60px;
}

.banner {
    display: grid;
    grid-template-columns: 1.2fr 0.8fr;
    gap: 24px;
    align-items: center;
    margin-bottom: 32px;
}

.banner img {
    width: 100%;
    border-radius: 20px;
    box-shadow: 0 18px 40px rgba(16, 24, 40, 0.12);
}

section {
    margin-bottom: 36px;
}

section h2 {
    margin-bottom: 18px;
    color: #111827;
}

.cards {
    display: grid;
    grid-template-columns: repeat(3, minmax(0, 1fr));
    gap: 18px;
}

.card {
    background: white;
    border-radius: 18px;
    padding: 20px;
    box-shadow: 0 10px 25px rgba(15, 23, 42, 0.08);
}

.card h3 {
    margin-bottom: 12px;
    font-size: 1.1rem;
}

.card p {
    color: #4b5563;
}

footer {
    background: #ffffff;
    border-top: 1px solid #e5e7eb;
    padding: 20px;
    text-align: center;
    color: #6b7280;
}

footer a {
    color: #2563eb;
    text-decoration: none;
}

main a {
    color: #1d4ed8;
    text-decoration: none;
    transition: color 0.2s ease;
}

main a:hover,
footer a:hover {
    color: #0f172a;
    text-decoration: underline;
}

.tool-list {
    display: grid;
    gap: 16px;
    grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
    list-style: none;
    padding: 0;
    margin: 0;
}

.tool-list li {
    background: #ffffff;
    border: 1px solid #e2e8f0;
    border-radius: 18px;
    box-shadow: 0 8px 20px rgba(15, 23, 42, 0.06);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.tool-list li:hover {
    transform: translateY(-2px);
    box-shadow: 0 16px 30px rgba(15, 23, 42, 0.1);
}

.tool-list a {
    display: block;
    padding: 24px;
    color: #111827;
    font-weight: 600;
    text-decoration: none;
}

.tool-list a:hover {
    color: #1d4ed8;
    background: transparent;
}

.card {
    background: white;
    border-radius: 18px;
    padding: 20px;
    box-shadow: 0 8px 18px rgba(15, 23, 42, 0.07);
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-3px);
    box-shadow: 0 16px 30px rgba(15, 23, 42, 0.1);
}

img.inline {
    width: 100%;
    border-radius: 16px;
    margin-top: 20px;
}

@media (max-width: 880px) {
    .banner {
        grid-template-columns: 1fr;
    }

    .cards {
        grid-template-columns: 1fr;
    }
}