:root {
  color-scheme: light dark;
  --bg: #fbf7f2;
  --fg: #1d1a17;
  --card: #ffffff;
  --line: #e4dccf;
  --accent: #0b5d73;
  --accent-fg: #ffffff;
  --warn-bg: #fff4d6;
  --warn-line: #e0b84a;
  --banner-bg: #7a1f00;
  --banner-fg: #fff7e8;
}

@media (prefers-color-scheme: dark) {
  :root {
    --bg: #14110f;
    --fg: #f1ebe3;
    --card: #1f1b18;
    --line: #3a332d;
    --accent: #5cc3dc;
    --accent-fg: #06222b;
    --warn-bg: #3b2f0d;
    --warn-line: #8c6d12;
  }
}

* { box-sizing: border-box; }

body {
  margin: 0;
  background: var(--bg);
  color: var(--fg);
  font: 16px/1.5 -apple-system, BlinkMacSystemFont, "Segoe UI", "Noto Sans Thai", sans-serif;
  padding-bottom: env(safe-area-inset-bottom);
}

.banner {
  position: sticky;
  top: 0;
  z-index: 5;
  display: flex;
  flex-direction: column;
  gap: 2px;
  padding: calc(10px + env(safe-area-inset-top)) 16px 10px;
  background: var(--banner-bg);
  color: var(--banner-fg);
  border-bottom: 4px solid #ffb703;
  font-size: 14px;
}

.banner strong { font-size: 15px; letter-spacing: 0.02em; }

main { max-width: 34rem; margin: 0 auto; padding: 16px; }

h1 { font-size: 1.5rem; margin: 8px 0; }
h2 { font-size: 1.05rem; margin: 0 0 8px; }
.lede { margin-top: 0; }

.card {
  background: var(--card);
  border: 1px solid var(--line);
  border-radius: 14px;
  padding: 14px 16px;
  margin: 14px 0;
}

.card.warn { background: var(--warn-bg); border-color: var(--warn-line); }
.small, .small li { font-size: 14px; }

label { display: block; font-weight: 600; margin: 8px 0 4px; }

input {
  width: 100%;
  min-height: 44px;
  padding: 8px 12px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: var(--bg);
  color: var(--fg);
  font: inherit;
  letter-spacing: 0.08em;
}

button {
  min-height: 44px;
  margin-top: 10px;
  padding: 10px 18px;
  border: 0;
  border-radius: 10px;
  background: var(--accent);
  color: var(--accent-fg);
  font: inherit;
  font-weight: 600;
}

button.secondary { background: transparent; color: var(--fg); border: 1px solid var(--line); }
button:disabled { opacity: 0.45; }
button:focus-visible, input:focus-visible { outline: 3px solid #ffb703; outline-offset: 2px; }

.msg { min-height: 1.4em; margin: 8px 0 0; font-size: 14px; }
.msg.bad { color: #b3261e; }
.msg.good { color: #1b7a3e; }

@media (prefers-color-scheme: dark) {
  .msg.bad { color: #ff8a80; }
  .msg.good { color: #7bd88f; }
}

[hidden] { display: none !important; }