/* ===================================
   Contact セクション (index.html 内)
   =================================== */

section#contact {
  padding-bottom: 2.5rem;
}

/* --- contact form --- */
.contact-form {
  display: grid;
  gap: 1.25rem;
  max-width: 480px;
  position: relative;
}

.contact-form label {
  display: grid;
  gap: 0.4rem;
  font-size: 0.875rem;
  color: var(--color-text-muted);
}

.contact-form input,
.contact-form textarea {
  font-family: var(--font-body);
  /* 16px (1rem) 未満にすると iOS Safari でフォーカス時に強制ズームが発火して画面がぼやけるため 1rem を指定 */
  font-size: 1rem;
  padding: 0.65rem 0.875rem;
  border: 1px solid var(--color-line);
  border-radius: var(--radius-sm);
  background: var(--color-surface);
  color: var(--color-text);
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.contact-form input::placeholder,
.contact-form textarea::placeholder {
  color: var(--color-text-muted);
  opacity: 0.5;
}

.contact-form input:focus-visible,
.contact-form textarea:focus-visible {
  outline: none;
  border-color: var(--color-matcha);
  box-shadow: 0 0 0 3px color-mix(in srgb, var(--color-matcha) 15%, transparent);
}

.contact-form button {
  justify-self: start;
  padding: 0.7rem 1.75rem;
  background: var(--color-matcha);
  color: var(--color-bg);
  border: none;
  border-radius: var(--radius-sm);
  font-family: var(--font-display);
  font-weight: 500;
  cursor: pointer;
  font-size: 0.9rem;
  transition: background 0.2s var(--ease-wa), transform 0.15s var(--ease-wa), box-shadow 0.2s var(--ease-wa);
}

.contact-form button:hover,
.contact-form button:focus-visible {
  background: var(--color-matcha-light);
  transform: translateY(-1px);
  box-shadow: 0 4px 14px rgba(122, 184, 122, 0.3);
}

.contact-form button:active {
  transform: translateY(0);
}

.contact-form button:disabled {
  opacity: 0.5;
  cursor: not-allowed;
}

.contact-status {
  font-family: var(--font-mono);
  font-size: 0.82rem;
  color: var(--color-matcha);
  min-height: 1.2em;
  margin: 0;
  transition: color 0.2s ease;
}

.contact-status--success {
  color: var(--color-matcha);
}

.contact-status--error {
  color: hsl(0 70% 65%);
}

/* --- Honeypot（ボット対策の隠しフィールド） --- */
.contact-form__honeypot {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip: rect(0, 0, 0, 0);
  white-space: nowrap;
  border: 0;
  pointer-events: none;
}

/* --- mathematical background: massive offscreen Math D (Complex Logarithmic Spiral) --- */
.contact__bg-math {
  position: absolute;
  bottom: 0;
  left: -240px;
  width: min(720px, 85vw);
  height: min(720px, 85vw);
  pointer-events: none;
  z-index: -1;
  opacity: 0.15;
}

.log-svg {
  width: 100%;
  height: 100%;
  overflow: visible;
}

.log-path {
  fill: none;
  stroke: var(--color-matcha);
  stroke-width: 0.5px;
  stroke-linecap: round;
  opacity: 0.75;
  vector-effect: non-scaling-stroke;
}