/* 登入卡片縮放比例：0.7 = 縮小 30% */
:root {
  --scale: 0.7;
}

.page-login {
  display: flex;
  justify-content: center;
  align-items: center;
  padding:
    calc(64px + env(safe-area-inset-top)) calc(16px + env(safe-area-inset-right)) calc(24px + env(safe-area-inset-bottom)) calc(16px + env(safe-area-inset-left));
  background:
    radial-gradient(circle at 20% 10%, var(--color-primary-soft), transparent 40%),
    radial-gradient(circle at 80% 90%, var(--color-primary-soft), transparent 40%),
    var(--color-bg);
}

/* ========== 登入卡片 ========== */
.app {
  width: 100%;
  max-width: calc(440px * var(--scale));
  padding: calc(48px * var(--scale)) calc(40px * var(--scale));
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-card);
  transition: background-color var(--transition);
}

/* ========== 品牌區 ========== */
.brand {
  text-align: center;
  margin-bottom: calc(32px * var(--scale));
}

.brand__logo {
  width: calc(64px * var(--scale));
  height: calc(64px * var(--scale));
  margin: 0 auto calc(20px * var(--scale));
  border-radius: calc(18px * var(--scale));
  display: grid;
  place-items: center;
  color: #fff;
  background: linear-gradient(135deg, #6366f1, #8b5cf6);
  box-shadow: 0 6px 18px rgba(99, 102, 241, 0.35);
}

.brand__logo svg {
  width: calc(32px * var(--scale));
  height: calc(32px * var(--scale));
}

.brand__title {
  font-size: max(18px, calc(1.75rem * var(--scale)));
  font-weight: 700;
  letter-spacing: 0.02em;
}

.brand__subtitle {
  margin-top: 4px;
  color: var(--color-text-muted);
  font-size: max(12px, calc(0.95rem * var(--scale)));
}

/* ========== 表單 ========== */
.form {
  display: flex;
  flex-direction: column;
  gap: calc(18px * var(--scale));
}

.field__label {
  display: block;
  font-size: max(12px, calc(0.875rem * var(--scale)));
  font-weight: 600;
  margin-bottom: calc(8px * var(--scale));
}

.input-wrap {
  position: relative;
  display: flex;
  align-items: center;
}

.input-wrap__icon {
  position: absolute;
  left: calc(14px * var(--scale));
  width: max(14px, calc(20px * var(--scale)));
  height: max(14px, calc(20px * var(--scale)));
  color: var(--color-text-muted);
  pointer-events: none;
  transition: color var(--transition);
}

.input-wrap input {
  width: 100%;
  height: calc(52px * var(--scale));
  padding: 0 calc(48px * var(--scale)) 0 calc(44px * var(--scale));
  font-size: 16px;
  /* 保持 16px，避免 iOS 自動縮放 */
  background: var(--color-input-bg);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-md);
  outline: none;
  transition: border-color var(--transition), box-shadow var(--transition), background var(--transition);
}

.input-wrap input::placeholder {
  color: var(--color-text-muted);
  opacity: 0.7;
  font-size: 14px;
}

.input-wrap input:focus {
  border-color: var(--color-primary);
  background: var(--color-surface);
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.input-wrap:focus-within .input-wrap__icon {
  color: var(--color-primary);
}

.input-wrap__toggle {
  position: absolute;
  right: 4px;
  width: calc(40px * var(--scale));
  height: calc(40px * var(--scale));
  display: grid;
  place-items: center;
  border: none;
  background: transparent;
  border-radius: var(--radius-sm);
  color: var(--color-text-muted);
  cursor: pointer;
}

.input-wrap__toggle:hover {
  color: var(--color-text);
}

.input-wrap__toggle svg {
  width: max(14px, calc(20px * var(--scale)));
  height: max(14px, calc(20px * var(--scale)));
}

.input-wrap__toggle .icon-eye-off {
  display: none;
}

.input-wrap__toggle[aria-pressed="true"] .icon-eye {
  display: none;
}

.input-wrap__toggle[aria-pressed="true"] .icon-eye-off {
  display: block;
}

.field__error {
  display: none;
  margin-top: 4px;
  font-size: 12px;
  color: var(--color-danger);
}

.field.is-invalid .field__error {
  display: block;
}

.field.is-invalid input {
  border-color: var(--color-danger);
}

.field.is-invalid input:focus {
  box-shadow: 0 0 0 3px rgba(225, 29, 72, 0.15);
}

.field.is-invalid .input-wrap__icon {
  color: var(--color-danger);
}

.form__row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 8px;
  font-size: max(12px, calc(0.9rem * var(--scale)));
}

.checkbox {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  cursor: pointer;
  user-select: none;
  color: var(--color-text-muted);
}

.checkbox input {
  position: absolute;
  opacity: 0;
  pointer-events: none;
}

.checkbox__box {
  width: 15px;
  height: 15px;
  border: 1.5px solid var(--color-border);
  border-radius: 4px;
  background: var(--color-input-bg);
  display: grid;
  place-items: center;
  transition: all var(--transition);
}

.checkbox__box::after {
  content: "";
  width: 4px;
  height: 8px;
  border: solid #fff;
  border-width: 0 2px 2px 0;
  transform: rotate(45deg) scale(0);
  margin-top: -2px;
  transition: transform var(--transition);
}

.checkbox input:checked+.checkbox__box {
  background: var(--color-primary);
  border-color: var(--color-primary);
}

.checkbox input:checked+.checkbox__box::after {
  transform: rotate(45deg) scale(1);
}

.checkbox input:focus-visible+.checkbox__box {
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.link {
  color: var(--color-primary);
  font-weight: 500;
}

.link:hover {
  text-decoration: underline;
}

.link--strong {
  font-weight: 700;
}

/* ========== 按鈕 ========== */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  border: none;
  cursor: pointer;
  border-radius: var(--radius-md);
  font-weight: 600;
  transition: background var(--transition), transform 0.1s ease,
    box-shadow var(--transition), opacity var(--transition);
}

.btn:active {
  transform: scale(0.98);
}

.btn--primary {
  width: 100%;
  height: calc(52px * var(--scale));
  margin-top: 4px;
  font-size: 14px;
  color: #fff;
  background: var(--color-primary);
  box-shadow: 0 4px 14px rgba(79, 70, 229, 0.35);
}

.btn--primary:hover {
  background: var(--color-primary-hover);
}

.btn--primary:focus-visible {
  outline: none;
  box-shadow: 0 0 0 3px var(--color-primary-soft);
}

.btn__spinner {
  display: none;
  width: 16px;
  height: 16px;
  border: 2px solid rgba(255, 255, 255, 0.4);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.btn.is-loading {
  pointer-events: none;
  opacity: 0.85;
}

.btn.is-loading .btn__text {
  display: none;
}

.btn.is-loading .btn__spinner {
  display: block;
}

@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

.signup {
  text-align: center;
  margin-top: calc(28px * var(--scale));
  font-size: max(12px, calc(0.9rem * var(--scale)));
  color: var(--color-text-muted);
}