:root {
      --bg: #e9edf4;
      --card: #ffffff;
      --text: #171d2c;
      --line: #dde3eb;
      --accent: #2563eb;
      --danger: #e11d48;
      --shadow: 0 22px 60px rgba(20, 32, 52, 0.14);
      --soft-shadow: 0 8px 24px rgba(20, 32, 52, 0.08);
      --radius: 24px;
    }

    * {
      box-sizing: border-box;
    }

    html,
    body {
      margin: 0;
      min-height: 100%;
      font-family: system-ui, -apple-system, BlinkMacSystemFont, "Hiragino Sans", "Yu Gothic", "Segoe UI", sans-serif;
      background: var(--bg);
      color: var(--text);
    }

    body {
      min-height: 100svh;
      display: grid;
      place-items: center;
      padding: max(16px, env(safe-area-inset-top)) max(14px, env(safe-area-inset-right)) max(16px, env(safe-area-inset-bottom)) max(14px, env(safe-area-inset-left));
    }

    .phone-card {
      width: min(100%, 460px);
      background: var(--card);
      border-radius: var(--radius);
      box-shadow: var(--shadow);
      padding: clamp(20px, 5.4vw, 28px);
    }

    h1 {
      margin: 0 0 20px;
      font-size: clamp(2rem, 8vw, 2.8rem);
      line-height: 1.15;
      letter-spacing: -0.05em;
      font-weight: 800;
    }

    .number-input {
      width: 100%;
      height: 72px;
      border: 1px solid var(--line);
      border-radius: 18px;
      background: #fff;
      color: var(--text);
      font-size: clamp(1.6rem, 8vw, 2.15rem);
      letter-spacing: 0.035em;
      padding: 10px 16px;
      outline: none;
    }

    .number-input:focus {
      border-color: rgba(37, 99, 235, 0.48);
      box-shadow: 0 0 0 4px rgba(37, 99, 235, 0.11);
    }

    .top-actions {
      display: grid;
      grid-template-columns: 1fr 1fr;
      gap: 12px;
      margin: 12px 0 18px;
    }

    .action-button {
      min-height: 56px;
      border-radius: 17px;
      font-size: clamp(1rem, 4vw, 1.08rem);
      font-weight: 800;
      cursor: pointer;
      touch-action: manipulation;
      transition: transform 0.08s ease, filter 0.12s ease, background 0.12s ease;
      -webkit-tap-highlight-color: transparent;
    }

    .action-button:active {
      transform: translateY(2px) scale(0.985);
    }

    .clear-button,
    .delete-button {
      background: #fff;
      border: 1px solid var(--line);
      box-shadow: var(--soft-shadow);
    }

    .clear-button {
      color: var(--danger);
    }

    .delete-button {
      color: var(--text);
    }

    .dial-button {
      width: 100%;
      min-height: 66px;
      border: 0;
      background: var(--accent);
      color: #fff;
      box-shadow: 0 10px 22px rgba(37, 99, 235, 0.28);
    }

    .dial-button:hover {
      filter: brightness(0.96);
    }

    @media (max-width: 360px) {
      .phone-card {
        padding: 18px;
        border-radius: 20px;
      }

      .top-actions {
        gap: 10px;
      }

      .action-button {
        font-size: 0.95rem;
      }
    }

/* ===== 共通固定フッター ===== */
:root {
  --sakurayama-footer-height: 56px;
}

html {
  min-height: 100%;
}

body {
  min-height: 100vh;
  min-height: 100dvh;
  padding-bottom: calc(var(--sakurayama-footer-height) + 14px) !important;
  box-sizing: border-box;
}

.site-footer {
  position: fixed !important;
  left: 0 !important;
  right: 0 !important;
  bottom: 0 !important;
  z-index: 2147483000 !important;
  width: 100% !important;
  min-height: var(--sakurayama-footer-height) !important;
  margin: 0 !important;
  padding: 6px 12px !important;
  display: flex !important;
  align-items: center !important;
  justify-content: center !important;
  box-sizing: border-box !important;
  text-align: center !important;
  background: rgba(248, 251, 255, 0.97) !important;
  border-top: 1px solid rgba(21, 101, 192, 0.28) !important;
  box-shadow: 0 -4px 14px rgba(15, 23, 42, 0.10) !important;
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
}

.site-footer .sakurayama-copyright {
  margin: 0 !important;
  color: #1565c0 !important;
  font-size: 1.02rem !important;
  font-weight: 700 !important;
  line-height: 1.35 !important;
}

.site-footer .sakurayama-copyright a {
  color: #1565c0 !important;
  text-decoration: none !important;
  font-weight: 700 !important;
}

.site-footer .sakurayama-copyright a:hover,
.site-footer .sakurayama-copyright a:focus-visible {
  color: #0d47a1 !important;
  text-decoration: underline !important;
}

@media (max-width: 480px) {
  :root {
    --sakurayama-footer-height: 52px;
  }
  .site-footer .sakurayama-copyright {
    font-size: 0.94rem !important;
  }
}

@media print {
  body {
    padding-bottom: 0 !important;
  }
  .site-footer {
    display: none !important;
  }
}