* { box-sizing: border-box; margin: 0; padding: 0; }
:root { --ink: #1c2733; --ink2: #5b6b7c; --line: #e3e8ee; --accent: #2563eb; --bg: #f7f9fb; }
body { font-family: -apple-system, "Segoe UI", "Microsoft YaHei", "PingFang SC", sans-serif; color: var(--ink); background: var(--bg); font-size: 15px; line-height: 1.7; overflow-x: hidden; }
a { color: var(--accent); text-decoration: none; }

.site-head { display: flex; align-items: center; justify-content: space-between; flex-wrap: wrap; gap: 10px; padding: 16px 24px; background: #fff; border-bottom: 1px solid var(--line); position: sticky; top: 0; z-index: 10; }
.brand { font-size: 18px; font-weight: 800; color: var(--ink); }
.brand small { color: var(--ink2); font-weight: 400; margin-left: 8px; font-size: 12px; }
.site-nav { display: flex; gap: 4px; flex-wrap: wrap; }
.site-nav a { padding: 6px 12px; border-radius: 8px; color: var(--ink2); font-size: 13.5px; }
.site-nav a:hover { background: #eef3fb; color: var(--accent); }

main { max-width: 860px; margin: 0 auto; padding: 28px 20px 60px; }
.hero { text-align: center; padding: 46px 10px 34px; }
.hero h1 { font-size: 34px; letter-spacing: 1px; }
.hero p { color: var(--ink2); margin-top: 10px; }

.tool-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(230px, 1fr)); gap: 14px; }
.tool-card { display: flex; gap: 12px; align-items: flex-start; background: #fff; border: 1.5px solid var(--line); border-radius: 14px; padding: 18px; transition: all .15s; color: var(--ink); }
.tool-card:hover { border-color: var(--accent); box-shadow: 0 6px 22px rgba(37,99,235,.10); transform: translateY(-2px); }
.tc-icon { font-size: 24px; }
.tool-card h3 { font-size: 15px; margin-bottom: 3px; }
.tool-card p { font-size: 12.5px; color: var(--ink2); }

.tool-page h1 { font-size: 26px; }
.intro { color: var(--ink2); margin: 8px 0 18px; font-size: 14px; }
.card { background: #fff; border: 1.5px solid var(--line); border-radius: 14px; padding: 22px; }
.howto, .related { margin-top: 26px; }
.howto h2, .related h2, .sub { font-size: 17px; margin: 18px 0 10px; }
.howto p { color: var(--ink2); font-size: 14px; }
.howto code { background: #eef2f7; padding: 1px 6px; border-radius: 5px; font-size: 13px; }

textarea, .txt { width: 100%; border: 1.5px solid var(--line); border-radius: 10px; padding: 11px 13px; font-size: 14px; font-family: inherit; background: #fff; resize: vertical; }
textarea:focus, .txt:focus { outline: none; border-color: var(--accent); }
.btn-row { display: flex; gap: 10px; margin: 12px 0; flex-wrap: wrap; align-items: center; }
.btn { border: 1.5px solid var(--accent); background: var(--accent); color: #fff; border-radius: 9px; padding: 9px 20px; font-size: 14px; font-weight: 600; cursor: pointer; font-family: inherit; }
.btn:hover { opacity: .9; }
.btn.primary { background: var(--accent); }
.btn.ghost { background: #fff; color: var(--accent); border-color: #c4d5f7; }
.btn.mini { padding: 3px 12px; font-size: 12px; border-radius: 7px; }
.sel { border: 1.5px solid var(--line); border-radius: 9px; padding: 8px 10px; font-size: 13.5px; background: #fff; }
.radio { display: inline-flex; align-items: center; gap: 6px; font-size: 13.5px; color: var(--ink2); cursor: pointer; }
.radio input { width: auto; accent-color: var(--accent); }
.btn-row.wrap { row-gap: 6px; }

.error { background: #fdecec; color: #a12622; border: 1px solid #f6c9c7; border-radius: 9px; padding: 10px 14px; margin: 10px 0; font-size: 13.5px; }
.code { background: #f4f6f9; border: 1.5px solid var(--line); border-radius: 10px; padding: 16px; min-height: 60px; font-family: Consolas, monospace; font-size: 13px; white-space: pre-wrap; word-break: break-all; }
.stats-grid { display: grid; grid-template-columns: repeat(auto-fill, minmax(150px, 1fr)); gap: 10px; margin-top: 14px; }
.stat { background: #f4f7fc; border-radius: 10px; padding: 12px 14px; text-align: center; }
.stat b { display: block; font-size: 20px; color: var(--accent); }
.stat span { font-size: 11.5px; color: var(--ink2); }

.result-stat { font-size: 13px; color: var(--accent); font-weight: 600; }
.now-box { display: flex; gap: 24px; flex-wrap: wrap; background: #f4f7fc; border-radius: 10px; padding: 14px 18px; font-size: 13.5px; color: var(--ink2); }
.now-box b { display: block; font-size: 16px; color: var(--ink); font-family: Consolas, monospace; }
.result-box table, .kv { margin-top: 10px; border-collapse: collapse; width: 100%; }
.kv td { padding: 8px 12px; border-bottom: 1px solid var(--line); font-size: 14px; }
.kv td:first-child { color: var(--ink2); width: 120px; }
.err-t { color: #c0392b; font-size: 13.5px; }

.drop-box { border: 2px dashed #b9c8de; border-radius: 14px; padding: 44px 20px; text-align: center; cursor: pointer; transition: all .15s; }
.drop-box:hover, .drop-box.over { border-color: var(--accent); background: #f0f5ff; }
.drop-box .muted { color: var(--ink2); font-size: 12.5px; margin-top: 6px; }
.img-cols { display: grid; grid-template-columns: 1fr 1fr; gap: 14px; }
.img-cols h3 { font-size: 14px; margin-bottom: 6px; }
.preview { width: 100%; border: 1.5px solid var(--line); border-radius: 10px; background: repeating-conic-gradient(#f0f0f0 0 25%, #fff 0 50%) 0 0/16px 16px; }
.size-tag { font-size: 12px; color: var(--ink2); font-weight: 400; }
.size-tag.ok { color: #16a34a; font-weight: 600; }
.btn-row label { font-size: 13.5px; color: var(--ink2); display: inline-flex; align-items: center; gap: 8px; }
input[type=range] { accent-color: var(--accent); }
.txt.sm { width: 100px; }

.swatch { height: 90px; border-radius: 12px; border: 1.5px solid var(--line); margin: 14px 0; transition: background .15s; }
.c-row { display: flex; align-items: center; gap: 12px; padding: 9px 0; border-bottom: 1px solid var(--line); }
.c-row span { width: 44px; color: var(--ink2); font-size: 13px; font-weight: 600; }
.c-row code { flex: 1; font-family: Consolas, monospace; font-size: 14px; }

.about { margin-top: 40px; color: var(--ink2); font-size: 14px; }
.about h2 { color: var(--ink); font-size: 18px; margin-bottom: 10px; }
.site-foot { text-align: center; color: #93a3b5; font-size: 12.5px; padding: 26px 16px; border-top: 1px solid var(--line); }
@media (max-width: 640px) { .img-cols { grid-template-columns: 1fr; } .hero h1 { font-size: 26px; } }