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

:root {
  --bg: #0a0a0f;
  --surface: #13131a;
  --surface2: #1c1c27;
  --border: rgba(255,255,255,0.08);
  --border2: rgba(255,255,255,0.14);
  --accent-btc: #f7931a;
  --accent-eth: #627eea;
  --accent-btc-dim: rgba(247,147,26,0.12);
  --accent-eth-dim: rgba(98,126,234,0.12);
  --text: #e8e8f0;
  --text2: #888899;
  --text3: #555566;
  --success: #3dd68c;
  --danger: #f05d5d;
  --mono: 'Space Mono', monospace;
  --display: 'Syne', sans-serif;
}

body.light-theme {
  --bg: #f5f5f7;
  --surface: #ffffff;
  --surface2: #f0f0f2;
  --border: rgba(0,0,0,0.08);
  --border2: rgba(0,0,0,0.14);
  --text: #1a1a2e;
  --text2: #666677;
  --text3: #aaaaaa;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: var(--mono);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding: 2rem 1rem 4rem;
}

.noise {
  position: fixed; inset: 0; z-index: 0; pointer-events: none; opacity: 0.03;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='n'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23n)'/%3E%3C/svg%3E");
}

.wrap { position: relative; z-index: 1; width: 100%; max-width: 680px; }

header { margin-bottom: 2.5rem; }

.logo {
  display: flex; align-items: center; gap: 10px; margin-bottom: 0.5rem;
}
.logo-icon {
  width: 36px; height: 36px; border-radius: 8px;
  background: linear-gradient(135deg, var(--accent-btc), var(--accent-eth));
  display: flex; align-items: center; justify-content: center;
  font-size: 18px;
}
h1 {
  font-family: var(--display);
  font-size: clamp(1.6rem, 5vw, 2.2rem);
  font-weight: 800;
  letter-spacing: -0.02em;
  background: linear-gradient(90deg, #fff 40%, var(--text2));
  -webkit-background-clip: text; -webkit-text-fill-color: transparent;
}
.subtitle {
  font-size: 0.78rem; color: var(--text3); letter-spacing: 0.04em;
  text-transform: uppercase; margin-top: 0.25rem;
}

.input-card {
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 14px;
  padding: 1.25rem;
  margin-bottom: 1.5rem;
  transition: border-color 0.2s;
}
.input-card.btc { border-color: rgba(247,147,26,0.3); }
.input-card.eth { border-color: rgba(98,126,234,0.3); }

.input-label {
  font-size: 0.72rem; color: var(--text3); letter-spacing: 0.06em;
  text-transform: uppercase; margin-bottom: 0.6rem;
  display: flex; align-items: center; gap: 8px;
}
.chain-badge {
  padding: 2px 8px; border-radius: 4px; font-size: 0.65rem;
  font-weight: 700; letter-spacing: 0.08em; transition: all 0.2s;
  display: none;
}
.chain-badge.btc { background: var(--accent-btc-dim); color: var(--accent-btc); display: inline-block; }
.chain-badge.eth { background: var(--accent-eth-dim); color: var(--accent-eth); display: inline-block; }

textarea {
  width: 100%; background: var(--surface2);
  border: 1px solid var(--border); border-radius: 8px;
  color: var(--text); font-family: var(--mono); font-size: 0.82rem;
  padding: 0.8rem 1rem; padding-right: 2.5rem; resize: none; outline: none;
  transition: border-color 0.2s; line-height: 1.5;
  height: 80px;
}
textarea:focus { border-color: var(--border2); }
textarea::placeholder { color: var(--text3); }

.textarea-container {
  position: relative; width: 100%;
}

.btn-clear-x {
  position: absolute; right: 0.5rem; top: 50%; transform: translateY(-50%);
  background: none; border: none; color: var(--text2); font-size: 1.5rem;
  padding: 0; width: 2rem; height: 2rem; display: flex; align-items: center;
  justify-content: center; cursor: pointer; transition: all 0.15s;
  font-family: var(--mono); font-weight: 700;
}
.btn-clear-x:hover { color: var(--text); }
.btn-clear-x:active { transform: translateY(-50%) scale(0.95); }

.btn-row { display: flex; gap: 10px; margin-top: 1rem; }

button {
  font-family: var(--mono); cursor: pointer; border: none; outline: none;
  border-radius: 8px; font-size: 0.82rem; font-weight: 700;
  transition: all 0.15s; letter-spacing: 0.02em;
}
.btn-decode {
  flex: 1; padding: 0.75rem 1rem;
  background: #8ac98d;
  color: #fff;
}
.btn-decode.eth-mode {
  background: #8ac98d;
}
.btn-decode:hover { opacity: 0.88; transform: translateY(-1px); }
.btn-decode:active { transform: translateY(0); opacity: 1; }
.btn-decode:disabled { opacity: 0.35; cursor: not-allowed; transform: none; }

.btn-theme-toggle {
  padding: 0.4rem 0.9rem; font-size: 0.72rem;
  background: var(--surface2); color: var(--text2);
  border: 1px solid var(--border);
  cursor: pointer; font-family: var(--mono);
}
.btn-theme-toggle:hover { color: var(--text); border-color: var(--border2); background: var(--border); }

.status {
  font-size: 0.78rem; color: var(--text3);
  margin-top: 0.75rem; min-height: 1.2em;
  display: flex; align-items: center; gap: 8px;
}
.spinner {
  width: 12px; height: 12px; border-radius: 50%;
  border: 2px solid var(--border); border-top-color: var(--accent-eth);
  animation: spin 0.7s linear infinite; display: none;
}
.spinner.btc { border-top-color: var(--accent-btc); }
@keyframes spin { to { transform: rotate(360deg); } }

.result-card {
  background: var(--surface); border: 1px solid var(--border);
  border-radius: 14px; overflow: hidden;
  animation: fadeUp 0.3s ease both;
}
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(8px); }
  to   { opacity: 1; transform: translateY(0); }
}

.result-header {
  padding: 0.9rem 1.25rem; border-bottom: 1px solid var(--border);
  display: flex; align-items: center; justify-content: space-between;
  background: var(--surface2);
}
.result-title {
  font-size: 0.72rem; text-transform: uppercase; letter-spacing: 0.08em;
  color: var(--text3);
}
.btn-copy {
  padding: 0.4rem 0.9rem; font-size: 0.72rem;
  background: var(--surface); color: var(--text2);
  border: 1px solid var(--border2); letter-spacing: 0.04em;
}
.btn-copy:hover { color: var(--text); border-color: var(--border2); background: var(--border); }
.btn-copy.copied { color: var(--success); border-color: rgba(61,214,140,0.3); background: rgba(61,214,140,0.05); }

.message-body {
  padding: 1.25rem;
  font-family: var(--mono);
  font-size: 0.85rem;
  line-height: 1.7;
  color: var(--text);
  white-space: pre-wrap;
  word-break: break-word;
}

.truncated-indicator {
  padding: 0 1.25rem 1rem;
  font-size: 0.75rem; color: var(--text3);
}

.btn-expand {
  padding: 0.35rem 0.8rem; font-size: 0.72rem;
  background: transparent; color: var(--text2);
  border: 1px solid var(--border); margin-left: 8px;
  display: inline-block;
}
.btn-expand:hover { color: var(--text); border-color: var(--border2); }

.explorer-links {
  padding: 0.9rem 1.25rem; border-top: 1px solid var(--border);
  display: flex; flex-wrap: wrap; gap: 8px;
}
.explorer-link {
  font-size: 0.72rem; color: var(--text3); text-decoration: none;
  padding: 0.4rem 0.85rem; border: 1px solid var(--border);
  border-radius: 6px; transition: all 0.15s; letter-spacing: 0.03em;
  font-family: var(--mono);
}
.explorer-link:hover { color: var(--text); border-color: var(--border2); background: var(--surface2); }
.explorer-link.btc:hover { color: var(--accent-btc); border-color: rgba(247,147,26,0.3); }
.explorer-link.eth:hover { color: var(--accent-eth); border-color: rgba(98,126,234,0.3); }

.err-card {
  background: rgba(240,93,93,0.07); border: 1px solid rgba(240,93,93,0.2);
  border-radius: 14px; padding: 1rem 1.25rem;
  font-size: 0.82rem; color: var(--danger);
  animation: fadeUp 0.3s ease both;
}

.empty-state {
  text-align: center; padding: 2rem 0;
  color: var(--text3); font-size: 0.8rem; line-height: 2;
}