:root {
    --bg: #F7FAFF;
    --card: #FFFFFF;
    --ink: #0F172A;
    --ink-weak: #475569;
    --line: #DCE7FF;
    --primary: #3A7BFF;
    --primary-hover: #2C63D6;
    --accent: #00B3FF;
    --shadow: 0 6px 20px rgba(16, 24, 40, .10);
    --radius: 16px;
}

/* ===== Reset (minimal) ===== */
* {
    box-sizing: border-box
}

html,
body {
    height: 100%
}

body {
    margin: 0;
    color: var(--ink);
    background: var(--bg);
    font-family: system-ui, -apple-system, "Segoe UI", Roboto, "Noto Sans JP", "Hiragino Kaku Gothic ProN", "Yu Gothic", "Helvetica Neue", Arial, sans-serif;
    line-height: 1.6;
}

img {
    max-width: 100%;
    display: block
}

h1,
h2,
h3 {
    margin: 0 0 .5rem 0;
    line-height: 1.25
}

p {
    margin: .25rem 0
}


.header {
    max-width: 1200px;
    margin: 24px auto 20px;
    padding: 20px 24px;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
}

.header h1 {
    font-size: 28px
}

.header p {
    color: var(--ink-weak);
    font-size: 14px
}

/* ===== Main layout ===== */
main {
    max-width: 1200px;
    margin: 0 auto;
    padding: 8px 12px 48px;
    gap: 20px;
}

div.tool-list {
    display: grid;
    grid-template-columns: repeat(auto-fill, minmax(200px, 1fr));
    gap: 20px;
}

div.tool-item {
    padding: 12px;
    background: var(--card);
    border: 1px solid var(--line);
    border-radius: var(--radius);
    box-shadow: var(--shadow);
    text-align: center
}

div.tool-item:hover {
    border-color: var(--primary-hover);
    border: 1px solid var(--primary);
}

p.tool-item-title {
    font-size: 18px;
    margin: 0 0 8px;
    border-bottom: 1px solid #00B3FF;
}

p.tool-item-discription {
    font-size: 14px;
}