:root {
  --bg: #f4f7fb;
  --card: #ffffff;
  --text: #14213d;
  --muted: #5f6b7a;
  --primary: #0b6e4f;
  --primary-soft: #dff6ee;
  --border: #d9e2ec;
  --danger: #9b1c1c;
}

* {
  box-sizing: border-box;
}

body {
  margin: 0;
  font-family: "PingFang SC", "Noto Sans SC", "Segoe UI", sans-serif;
  background: radial-gradient(circle at top left, #fef7ea, var(--bg) 35%);
  color: var(--text);
}

.app {
  width: min(960px, 100%);
  margin: 0 auto;
  padding: 16px;
}

.hero h1 {
  margin: 6px 0;
  font-size: clamp(24px, 6vw, 36px);
}

.hero p {
  margin: 0 0 12px;
  color: var(--muted);
}

.card {
  background: var(--card);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 14px;
  margin-bottom: 12px;
  box-shadow: 0 2px 8px rgba(20, 33, 61, 0.06);
}

.card h2 {
  margin: 0 0 12px;
  font-size: 17px;
}

.grid {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
}

label {
  display: grid;
  gap: 6px;
  font-size: 13px;
  color: var(--muted);
}

input {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 16px;
  color: var(--text);
  background: #fff;
}

input:focus {
  outline: 2px solid #4cae8c;
  border-color: #4cae8c;
}

.actions {
  display: flex;
  gap: 8px;
  margin-top: 12px;
  flex-wrap: wrap;
}

button {
  border: 0;
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 14px;
  color: #fff;
  background: var(--primary);
}

button.ghost {
  color: var(--text);
  background: var(--primary-soft);
}

.result-main {
  display: grid;
  grid-template-columns: 1fr;
  gap: 10px;
  margin-bottom: 10px;
}

.k {
  margin: 0;
  color: var(--muted);
  font-size: 12px;
}

.v {
  margin: 6px 0 0;
  font-size: 28px;
  font-weight: 700;
  letter-spacing: 0.2px;
}

.lines p {
  margin: 8px 0;
  font-size: 14px;
}

.history {
  list-style: none;
  padding: 0;
  margin: 10px 0 0;
  display: grid;
  gap: 8px;
}

.history li {
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 8px 10px;
  background: #fcfdff;
  font-size: 13px;
}

.note {
  color: var(--muted);
  font-size: 12px;
  padding: 0 2px 10px;
}

.error {
  color: var(--danger);
  font-size: 12px;
  margin-top: 6px;
}

@media (min-width: 760px) {
  .app {
    padding: 20px;
  }

  .grid {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }

  .result-main {
    grid-template-columns: repeat(2, minmax(0, 1fr));
  }
}

.meta {
  margin: 10px 2px 0;
  font-size: 12px;
  color: var(--muted);
}

select {
  width: 100%;
  border: 1px solid var(--border);
  border-radius: 10px;
  padding: 10px 12px;
  font-size: 16px;
  color: var(--text);
  background: #fff;
}

select:focus {
  outline: 2px solid #4cae8c;
  border-color: #4cae8c;
}

.mode-switch {
  display: flex;
  gap: 16px;
  margin-bottom: 12px;
}

.mode-switch label {
  display: flex;
  align-items: center;
  gap: 6px;
  color: var(--text);
}

.hidden {
  display: none;
}

.section-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 10px;
}

.entry-actions {
  display: grid;
  gap: 10px;
}

.entry-actions button {
  text-align: left;
  padding: 14px;
}