/* ============ 小文卡片 · 设计令牌 ============ */
:root {
  --ink: #141210;
  --paper: #F1F1EF;
  --red: #CE1432;
  --cream: #EDEAE3;
  --sub: #5A544C;
  --faint: #9A948C;
  --hair: #D8D6D1;
  --ink-bright: #DCD7CE;
  --ink-note: #A39D93;
  --ink-line: #3A3530;
  --serif: "Noto Serif SC", "Songti SC", "STSong", "SimSun", serif;
  --sans: "PingFang SC", "Hiragino Sans GB", "Microsoft YaHei", sans-serif;
}

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

html { scroll-behavior: smooth; }

body {
  background: var(--paper);
  color: var(--ink);
  font-family: var(--sans);
  font-size: 16px;
  line-height: 1.8;
  -webkit-font-smoothing: antialiased;
}

::selection { background: var(--red); color: var(--cream); }

/* ============ 导航 ============ */
.nav {
  position: sticky; top: 0; z-index: 50;
  background: rgba(241, 241, 239, .88);
  backdrop-filter: blur(10px);
  border-bottom: 1px solid var(--hair);
}
.nav-inner {
  max-width: 1120px; margin: 0 auto; padding: 14px 24px;
  display: flex; align-items: center; justify-content: space-between;
}
.brand { display: flex; align-items: center; gap: 10px; }
.brand-seal {
  display: inline-flex; align-items: center; justify-content: center;
  width: 34px; height: 34px; border-radius: 7px;
  background: var(--red); color: var(--cream);
  font-family: var(--serif); font-weight: 600; font-size: 18px;
}
.brand-seal.small { width: 26px; height: 26px; font-size: 14px; border-radius: 6px; }
.brand-name { font-family: var(--serif); font-weight: 600; font-size: 18px; letter-spacing: .1em; }
.nav-links { display: flex; gap: 28px; }
.nav-links a {
  color: var(--sub); text-decoration: none; font-size: 14px; letter-spacing: .12em;
  transition: color .2s;
}
.nav-links a:hover { color: var(--red); }

/* ============ 按钮 ============ */
.btn {
  display: inline-block; padding: 13px 30px; border-radius: 4px;
  font-size: 15px; letter-spacing: .18em; text-decoration: none;
  cursor: pointer; border: 1px solid transparent; transition: all .2s;
  font-family: var(--sans);
}
.btn-primary { background: var(--ink); color: var(--cream); }
.btn-primary:hover { background: var(--red); }
.btn-ghost { background: transparent; color: var(--ink); border-color: var(--ink); }
.btn-ghost:hover { color: var(--red); border-color: var(--red); }

/* ============ HERO ============ */
.hero {
  max-width: 1120px; margin: 0 auto; padding: 110px 24px 90px;
  text-align: center;
}
.hero-kicker {
  font-size: 12px; letter-spacing: .5em; color: var(--faint); margin-bottom: 26px;
}
.hero-title {
  font-family: var(--serif); font-weight: 900;
  font-size: clamp(38px, 6vw, 68px); line-height: 1.35; letter-spacing: .04em;
}
.hero-title .accent { color: var(--red); }
.hero-sub { margin-top: 26px; color: var(--sub); font-size: 17px; }
.hero-actions { margin-top: 40px; display: flex; gap: 16px; justify-content: center; flex-wrap: wrap; }

.hero-sample { margin-top: 80px; display: flex; justify-content: center; }
.sample-card {
  width: min(420px, 88vw); background: var(--ink); color: var(--cream);
  border-radius: 10px; padding: 34px 34px 30px; text-align: left;
  box-shadow: 0 30px 60px -20px rgba(20, 18, 16, .45);
  transform: rotate(-1.2deg);
}
.sample-head { font-size: 12px; letter-spacing: .3em; color: var(--ink-note); display: flex; align-items: center; gap: 8px; }
.sample-head .dot { width: 8px; height: 8px; background: var(--red); border-radius: 2px; display: inline-block; }
.sample-rule { height: 1px; background: var(--ink-line); margin: 18px 0 26px; }
.sample-quote {
  font-family: var(--serif); font-weight: 600;
  font-size: 26px; line-height: 1.9; letter-spacing: .08em;
}
.sample-foot { margin-top: 28px; display: flex; align-items: flex-end; justify-content: space-between; }
.sample-sign { font-family: var(--serif); color: var(--ink-bright); font-size: 15px; letter-spacing: .1em; }
.sample-seal {
  width: 40px; height: 40px; border-radius: 6px; background: var(--red); color: var(--cream);
  display: inline-flex; align-items: center; justify-content: center;
  font-family: var(--serif); font-size: 20px;
}

/* ============ 区块头 ============ */
.section-head { text-align: center; margin-bottom: 56px; }
.section-kicker { font-size: 12px; letter-spacing: .5em; color: var(--faint); margin-bottom: 14px; }
.section-head h2 {
  font-family: var(--serif); font-weight: 900; font-size: clamp(28px, 4vw, 40px); letter-spacing: .06em;
}

/* ============ STUDIO ============ */
.studio { max-width: 1120px; margin: 0 auto; padding: 100px 24px; border-top: 1px solid var(--hair); }
.studio-grid {
  display: grid; grid-template-columns: 400px 1fr; gap: 48px; align-items: start;
}
@media (max-width: 900px) { .studio-grid { grid-template-columns: 1fr; } }

.panel { display: flex; flex-direction: column; gap: 22px; }
.field { display: flex; flex-direction: column; gap: 8px; flex: 1; }
.field-row { display: flex; gap: 16px; flex-wrap: wrap; }
.field label { font-size: 13px; letter-spacing: .15em; color: var(--sub); }
.field output { color: var(--red); font-weight: 600; }

textarea, input[type="text"], select {
  width: 100%; padding: 12px 14px; border: 1px solid var(--hair); border-radius: 4px;
  background: #fff; color: var(--ink); font-size: 15px; font-family: var(--sans);
  outline: none; transition: border-color .2s; resize: vertical;
}
textarea:focus, input[type="text"]:focus, select:focus { border-color: var(--ink); }

input[type="range"] { width: 100%; accent-color: var(--red); }

.seg { display: flex; border: 1px solid var(--hair); border-radius: 4px; overflow: hidden; }
.seg-btn {
  flex: 1; padding: 11px 0; background: #fff; border: none; cursor: pointer;
  font-size: 14px; letter-spacing: .15em; color: var(--sub); transition: all .2s;
}
.seg-btn.active { background: var(--ink); color: var(--cream); }

.style-row { display: grid; grid-template-columns: repeat(2, 1fr); gap: 10px; }
.style-chip {
  display: flex; align-items: center; gap: 10px; padding: 10px 14px;
  background: #fff; border: 1px solid var(--hair); border-radius: 4px;
  font-size: 14px; letter-spacing: .1em; color: var(--sub); cursor: pointer; transition: all .2s;
}
.style-chip.active { border-color: var(--ink); color: var(--ink); box-shadow: inset 0 0 0 1px var(--ink); }
.sw { width: 22px; height: 22px; border-radius: 4px; border: 1px solid var(--hair); flex: none; }
.sw-paper { background: var(--paper); }
.sw-ink { background: var(--ink); }
.sw-cinnabar { background: linear-gradient(90deg, var(--red) 3px, var(--paper) 3px); }
.sw-vertical { background: repeating-linear-gradient(90deg, var(--ink) 0 2px, transparent 2px 7px), var(--ink); background-color: var(--ink); }

.logo-row { display: flex; align-items: center; gap: 12px; flex-wrap: wrap; }
.logo-btn {
  padding: 10px 18px; border: 1px dashed var(--faint); border-radius: 4px;
  font-size: 13px; letter-spacing: .15em; color: var(--sub); cursor: pointer; transition: all .2s;
}
.logo-btn:hover { border-color: var(--ink); color: var(--ink); }
.logo-clear {
  background: none; border: none; color: var(--red); font-size: 13px; cursor: pointer; letter-spacing: .1em;
}
.logo-name { font-size: 12px; color: var(--faint); max-width: 160px; overflow: hidden; text-overflow: ellipsis; white-space: nowrap; }

.actions { display: flex; gap: 14px; margin-top: 6px; flex-wrap: wrap; }
.hint { font-size: 13px; color: var(--faint); min-height: 20px; }
.hint.ok { color: #2e7d4f; }
.hint.err { color: var(--red); }

.preview-frame {
  background: #fff; border: 1px solid var(--hair); border-radius: 8px;
  padding: 28px; display: flex; justify-content: center;
  background-image:
    linear-gradient(45deg, #fafafa 25%, transparent 25%, transparent 75%, #fafafa 75%),
    linear-gradient(45deg, #fafafa 25%, transparent 25%, transparent 75%, #fafafa 75%);
  background-size: 24px 24px; background-position: 0 0, 12px 12px;
}
#cardCanvas { max-width: 100%; height: auto; border-radius: 4px; box-shadow: 0 16px 40px -18px rgba(20,18,16,.35); }
.preview-note { text-align: center; margin-top: 14px; font-size: 12px; letter-spacing: .2em; color: var(--faint); }

/* ============ CHANNELS ============ */
.channels { max-width: 1120px; margin: 0 auto; padding: 100px 24px; border-top: 1px solid var(--hair); }
.channel-grid { display: grid; grid-template-columns: 1fr 1fr; gap: 28px; }
@media (max-width: 800px) { .channel-grid { grid-template-columns: 1fr; } }
.channel-card {
  border: 1px solid var(--hair); border-radius: 8px; padding: 40px 36px;
  display: flex; flex-direction: column; gap: 14px; align-items: flex-start;
}
.channel-card h3 { font-family: var(--serif); font-size: 26px; font-weight: 600; letter-spacing: .1em; }
.channel-card p { color: var(--sub); font-size: 15px; }
.channel-card code { background: rgba(20,18,16,.06); padding: 2px 6px; border-radius: 3px; font-size: 13px; }
.channel-tag { font-size: 11px; letter-spacing: .4em; color: var(--red); }
.channel-card.dark { background: var(--ink); border-color: var(--ink); }
.channel-card.dark h3 { color: var(--cream); }
.channel-card.dark p { color: var(--ink-note); }
.channel-card.dark code { background: rgba(237,234,227,.1); color: var(--ink-bright); }
.qr-placeholder {
  margin-top: 8px; width: 120px; height: 120px; border: 1px dashed var(--ink-line); border-radius: 6px;
  display: flex; align-items: center; justify-content: center; text-align: center;
  font-size: 11px; color: var(--ink-note); letter-spacing: .1em; line-height: 1.7;
}

/* ============ FEATURES ============ */
.features { max-width: 1120px; margin: 0 auto; padding: 100px 24px; border-top: 1px solid var(--hair); }
.feature-list {
  list-style: none; display: grid; grid-template-columns: repeat(3, 1fr); gap: 1px;
  background: var(--hair); border: 1px solid var(--hair);
}
@media (max-width: 800px) { .feature-list { grid-template-columns: 1fr; } }
.feature-list li {
  background: var(--paper); padding: 32px 28px; display: flex; flex-direction: column; gap: 10px;
}
.feature-list b {
  font-family: var(--serif); font-size: 18px; font-weight: 600; letter-spacing: .12em;
}
.feature-list b::before {
  content: ""; display: block; width: 18px; height: 3px; background: var(--red); margin-bottom: 14px;
}
.feature-list span { font-size: 14px; color: var(--sub); }

/* ============ FOOTER ============ */
.footer { border-top: 1px solid var(--hair); }
.footer-inner {
  max-width: 1120px; margin: 0 auto; padding: 30px 24px;
  display: flex; align-items: center; gap: 12px; flex-wrap: wrap;
  font-size: 13px; color: var(--sub); letter-spacing: .1em;
}
.footer-dim { margin-left: auto; color: var(--faint); font-size: 12px; }

@media (max-width: 640px) {
  .br-pc { display: none; }
  .nav-links { gap: 16px; }
  .hero { padding-top: 70px; }
}