/* ============================================
   iOS OTA Distribution - Main Stylesheet
   ============================================ */

:root {
  --color-primary: #007aff;
  --color-primary-hover: #0066d6;
  --color-primary-light: rgba(0, 122, 255, 0.12);
  --color-success: #34c759;
  --color-warning: #ff9500;
  --color-error: #ff3b30;

  --color-bg: #f5f5f7;
  --color-surface: #ffffff;
  --color-surface-secondary: #f2f2f7;
  --color-text: #1d1d1f;
  --color-text-secondary: #6e6e73;
  --color-text-tertiary: #aeaeb2;
  --color-border: #d2d2d7;
  --color-divider: rgba(60, 60, 67, 0.08);

  --radius-sm: 8px;
  --radius-md: 12px;
  --radius-lg: 16px;
  --radius-xl: 20px;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 3px rgba(0, 0, 0, 0.08);
  --shadow-md: 0 4px 12px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 8px 30px rgba(0, 0, 0, 0.12);

  --font-sans: -apple-system, BlinkMacSystemFont, "SF Pro Display", "SF Pro Text", "Helvetica Neue", Arial, sans-serif;
  --font-mono: "SF Mono", "Menlo", "Monaco", "Consolas", monospace;

  --max-width: 480px;

  --transition-fast: 0.2s ease;
  --transition-normal: 0.35s ease;
}

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

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

body {
  font-family: var(--font-sans);
  background-color: var(--color-bg);
  color: var(--color-text);
  line-height: 1.6;
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  transition: background-color var(--transition-normal), color var(--transition-normal);
}

.container {
  width: 100%;
  max-width: var(--max-width);
  padding: 24px 20px;
  margin: 0 auto;
}

/* ========== Header ========== */

.app-header {
  text-align: center;
  padding: 40px 0 24px;
}

.app-icon {
  width: 96px;
  height: 96px;
  border-radius: var(--radius-xl);
  background: var(--color-surface);
  box-shadow: var(--shadow-md);
  margin: 0 auto 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  overflow: hidden;
  transition: background-color var(--transition-normal);
}

.app-icon img {
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.app-icon-placeholder {
  width: 100%;
  height: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  background: linear-gradient(135deg, #007aff, #5856d6);
  color: #fff;
  font-size: 36px;
  font-weight: 700;
}

.app-name {
  font-size: 24px;
  font-weight: 700;
  letter-spacing: -0.02em;
  margin-bottom: 4px;
}

.app-version {
  font-size: 16px;
  color: var(--color-text-secondary);
  font-weight: 400;
}


/* ========== Card ========== */

.card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
  padding: 20px;
  margin-bottom: 16px;
  transition: background-color var(--transition-normal), box-shadow var(--transition-normal);
}

.card-title {
  font-size: 14px;
  font-weight: 600;
  color: var(--color-text-secondary);
  text-transform: uppercase;
  letter-spacing: 0.05em;
  margin-bottom: 12px;
}

/* ========== Info List ========== */

.info-list {
  list-style: none;
}

.info-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: 10px 0;
  border-bottom: 1px solid var(--color-divider);
}

.info-item:last-child {
  border-bottom: none;
}

.info-label {
  font-size: 15px;
  color: var(--color-text-secondary);
}

.info-value {
  font-size: 15px;
  font-weight: 500;
  color: var(--color-text);
  text-align: right;
}

/* ========== Release Notes ========== */

.release-notes {
  line-height: 1.8;
}

.release-notes ul {
  list-style: none;
  padding: 0;
}

.release-notes li {
  position: relative;
  padding: 6px 0 6px 24px;
  font-size: 15px;
  color: var(--color-text);
}

.release-notes li::before {
  content: "✓";
  position: absolute;
  left: 0;
  color: var(--color-success);
  font-weight: 600;
}

.release-notes p {
  font-size: 15px;
  color: var(--color-text-secondary);
  margin-bottom: 4px;
}

/* ========== Install Button ========== */

.install-section {
  text-align: center;
  padding: 12px 0;
}

.btn-install {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  width: 100%;
  max-width: 280px;
  padding: 16px 32px;
  background: var(--color-primary);
  color: #fff;
  font-size: 17px;
  font-weight: 600;
  font-family: inherit;
  border: none;
  border-radius: var(--radius-full);
  cursor: pointer;
  transition: background var(--transition-fast), transform var(--transition-fast), opacity var(--transition-fast);
  -webkit-tap-highlight-color: transparent;
  user-select: none;
  text-decoration: none;
}

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

.btn-install:active {
  transform: scale(0.97);
}

.btn-install:disabled,
.btn-install[disabled] {
  opacity: 0.5;
  cursor: not-allowed;
  transform: none;
  pointer-events: none;
}

.btn-install .spinner {
  display: none;
  width: 20px;
  height: 20px;
  border: 2.5px solid rgba(255, 255, 255, 0.3);
  border-top-color: #fff;
  border-radius: 50%;
  animation: spin 0.7s linear infinite;
}

.btn-install.loading .spinner {
  display: inline-block;
}

.btn-install.loading .btn-text {
  opacity: 0.8;
}

/* ========== Steps / Instructions ========== */

.instruction-steps {
  counter-reset: step;
  list-style: none;
  padding: 0;
}

.instruction-step {
  position: relative;
  padding: 8px 0 8px 36px;
  font-size: 15px;
  color: var(--color-text-secondary);
  line-height: 1.6;
}

.instruction-step::before {
  counter-increment: step;
  content: counter(step);
  position: absolute;
  left: 0;
  top: 8px;
  width: 24px;
  height: 24px;
  background: var(--color-primary-light);
  color: var(--color-primary);
  font-size: 13px;
  font-weight: 600;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
}

strong {
  font-weight: 600;
  color: var(--color-text);
}

/* ========== Theme Toggle ========== */

.theme-toggle {
  position: fixed;
  top: 16px;
  right: 16px;
  z-index: 100;
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-sm);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 18px;
  transition: background var(--transition-fast), border-color var(--transition-fast);
  -webkit-tap-highlight-color: transparent;
}

.theme-toggle:hover {
  background: var(--color-surface-secondary);
}

.theme-toggle:active {
  transform: scale(0.92);
}

/* ========== Footer ========== */

.app-footer {
  text-align: center;
  padding: 24px 0 40px;
}

.app-footer a {
  color: var(--color-text-tertiary);
  text-decoration: none;
  font-size: 13px;
  transition: color var(--transition-fast);
}

.app-footer a:hover {
  color: var(--color-primary);
}

/* ========== Loading / Error States ========== */

.skeleton {
  background: linear-gradient(90deg, var(--color-surface-secondary) 25%, var(--color-border) 50%, var(--color-surface-secondary) 75%);
  background-size: 200% 100%;
  animation: shimmer 1.5s ease-in-out infinite;
  border-radius: var(--radius-sm);
}

.skeleton-line {
  height: 16px;
  margin-bottom: 8px;
  width: 100%;
}

.skeleton-line:last-child {
  width: 60%;
}

.error-state {
  text-align: center;
  padding: 20px;
}

.error-state .error-icon {
  font-size: 32px;
  margin-bottom: 8px;
}

.error-state p {
  font-size: 14px;
  color: var(--color-text-secondary);
}

/* ========== Toast ========== */

.toast {
  position: fixed;
  bottom: 32px;
  left: 50%;
  transform: translateX(-50%) translateY(80px);
  background: var(--color-text);
  color: var(--color-bg);
  padding: 12px 24px;
  border-radius: var(--radius-full);
  font-size: 14px;
  font-weight: 500;
  z-index: 200;
  opacity: 0;
  transition: transform var(--transition-normal), opacity var(--transition-normal);
  pointer-events: none;
  white-space: nowrap;
}

.toast.visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ========== Responsive ========== */

@media (max-width: 480px) {
  .container {
    padding: 16px 16px;
  }

  .app-header {
    padding: 24px 0 20px;
  }

  .app-icon {
    width: 80px;
    height: 80px;
  }

  .app-name {
    font-size: 22px;
  }

  .card {
    padding: 16px;
  }

  .btn-install {
    max-width: 100%;
  }
}

@media (min-width: 768px) {
  .container {
    padding: 32px 24px;
  }
}