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

:root {
  --bg: #0a0a0a;
  --surface: #141414;
  --border: rgba(255,255,255,0.08);
  --text: #f0f0f0;
  --text-sub: rgba(240,240,240,0.5);
  --accent: #e8e8e8;
  --red: #c82000;
  --font-mono: 'Space Mono', 'JetBrains Mono', monospace;
  --font-sans: 'Inter', 'Noto Sans JP', sans-serif;
}

html, body {
  height: 100%;
  background: var(--bg);
  color: var(--text);
  font-family: var(--font-sans);
}

.gate-screen {
  min-height: 100vh;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}

.gate-card {
  width: 100%;
  max-width: 400px;
  background: var(--surface);
  border: 1px solid var(--border);
  border-radius: 4px;
  padding: 40px 32px 32px;
  display: flex;
  flex-direction: column;
  gap: 20px;
}

.gate-logo {
  font-family: var(--font-mono);
  font-size: 10px;
  letter-spacing: 0.3em;
  color: var(--text-sub);
  text-transform: uppercase;
}

.gate-title {
  font-family: var(--font-mono);
  font-size: 20px;
  font-weight: 700;
  color: var(--text);
  letter-spacing: 0.04em;
}

.gate-sub {
  font-size: 13px;
  color: var(--text-sub);
  line-height: 1.6;
}

.gate-field {
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.gate-label {
  font-family: var(--font-mono);
  font-size: 9px;
  letter-spacing: 0.2em;
  text-transform: uppercase;
  color: var(--text-sub);
}

.gate-select,
.gate-input {
  width: 100%;
  background: #0a0a0a;
  border: 1px solid var(--border);
  border-radius: 2px;
  color: var(--text);
  font-family: var(--font-mono);
  font-size: 13px;
  padding: 10px 12px;
  outline: none;
  transition: border-color 0.15s;
  appearance: none;
}

.gate-select:focus,
.gate-input:focus {
  border-color: rgba(255,255,255,0.3);
}

.gate-input::placeholder {
  color: rgba(240,240,240,0.2);
}

.gate-error {
  font-size: 12px;
  color: var(--red);
  min-height: 16px;
  line-height: 1.5;
}

.gate-btn {
  width: 100%;
  background: var(--text);
  color: var(--bg);
  border: none;
  border-radius: 2px;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 700;
  letter-spacing: 0.1em;
  padding: 14px;
  cursor: pointer;
  transition: opacity 0.15s;
}

.gate-btn:hover:not(:disabled) {
  opacity: 0.85;
}

.gate-btn:disabled {
  opacity: 0.4;
  cursor: not-allowed;
}

.gate-hint {
  font-size: 11px;
  color: var(--text-sub);
  line-height: 1.7;
  text-align: center;
}