/* ===== CSS Custom Properties ===== */
:root {
  --emerald-50: #ecfdf5;
  --emerald-100: #d1fae5;
  --emerald-400: #34d399;
  --emerald-500: #10b981;
  --emerald-600: #059669;
  --emerald-700: #047857;
  --slate-50: #f8fafc;
  --slate-100: #f1f5f9;
  --slate-200: #e2e8f0;
  --slate-300: #cbd5e1;
  --slate-400: #94a3b8;
  --slate-500: #64748b;
  --slate-600: #475569;
  --slate-700: #334155;
  --slate-800: #1e293b;
  --slate-900: #0f172a;

  --bg-gradient-from: var(--slate-50);
  --bg-gradient-to: var(--slate-100);
  --card-bg: #ffffff;
  --card-shadow: 0 20px 25px -5px rgb(0 0 0 / 0.1), 0 8px 10px -6px rgb(0 0 0 / 0.1);
  --text-primary: var(--slate-900);
  --text-secondary: var(--slate-600);
  --text-muted: var(--slate-400);
  --border-color: var(--slate-300);
  --input-bg: #ffffff;
  --badge-bg: var(--emerald-50);
  --badge-text: var(--emerald-700);
  --footer-text: var(--slate-500);

  --font-family: 'Inter', system-ui, -apple-system, BlinkMacSystemFont, 'Segoe UI', sans-serif;
}

/* ===== Dark Mode ===== */
@media (prefers-color-scheme: dark) {
  :root {
    --bg-gradient-from: #0c1220;
    --bg-gradient-to: var(--slate-900);
    --card-bg: var(--slate-800);
    --card-shadow: 0 20px 25px -5px rgb(0 0 0 / 0.3), 0 8px 10px -6px rgb(0 0 0 / 0.3);
    --text-primary: var(--slate-50);
    --text-secondary: var(--slate-300);
    --text-muted: var(--slate-500);
    --border-color: var(--slate-600);
    --input-bg: var(--slate-700);
    --badge-bg: rgba(16, 185, 129, 0.15);
    --badge-text: var(--emerald-400);
    --footer-text: var(--slate-400);
  }
}

/* ===== Reset & Base ===== */
*, *::before, *::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

html {
  font-size: 16px;
  -webkit-text-size-adjust: 100%;
}

body {
  font-family: var(--font-family);
  color: var(--text-primary);
  background: linear-gradient(135deg, var(--bg-gradient-from), var(--bg-gradient-to));
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: 1.5rem;
  line-height: 1.6;
  animation: fadeIn 0.6s ease-out;
}

@keyframes fadeIn {
  from { opacity: 0; transform: translateY(12px); }
  to { opacity: 1; transform: translateY(0); }
}

/* ===== Language Switcher ===== */
.lang-switcher {
  position: fixed;
  top: 1.25rem;
  right: 1.25rem;
  display: flex;
  gap: 0.25rem;
  background: var(--card-bg);
  border-radius: 0.625rem;
  padding: 0.25rem;
  box-shadow: 0 1px 3px rgb(0 0 0 / 0.1);
  z-index: 10;
}

.lang-btn {
  background: none;
  border: none;
  padding: 0.375rem 0.75rem;
  border-radius: 0.5rem;
  font-size: 0.8125rem;
  font-weight: 500;
  color: var(--text-muted);
  cursor: pointer;
  transition: all 0.2s ease;
  font-family: var(--font-family);
}

.lang-btn:hover {
  color: var(--text-primary);
  background: var(--slate-100);
}

.lang-btn.active {
  background: var(--emerald-500);
  color: #ffffff;
}

@media (prefers-color-scheme: dark) {
  .lang-btn:hover {
    background: var(--slate-700);
  }
}

/* ===== Card ===== */
.card {
  background: var(--card-bg);
  border-radius: 1.5rem;
  box-shadow: var(--card-shadow);
  padding: 3rem 2.5rem;
  max-width: 28rem;
  width: 100%;
  text-align: center;
}

/* ===== Logo ===== */
.logo-container {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 4.5rem;
  height: 4.5rem;
  background: var(--emerald-500);
  border-radius: 1rem;
  margin-bottom: 1.25rem;
  position: relative;
  overflow: hidden;
}

.logo-container::after {
  content: '';
  position: absolute;
  inset: 0;
  background: linear-gradient(135deg, transparent 40%, rgba(255,255,255,0.15) 100%);
  border-radius: 1rem;
}

.logo-container svg {
  width: 2.25rem;
  height: 2.25rem;
  color: #ffffff;
  position: relative;
  z-index: 1;
}

/* ===== Typography ===== */
.app-name {
  font-size: 2.25rem;
  font-weight: 800;
  color: var(--text-primary);
  letter-spacing: -0.025em;
  margin-bottom: 0.25rem;
}

.tagline {
  font-size: 1rem;
  color: var(--text-secondary);
  font-weight: 400;
  margin-bottom: 1.5rem;
}

/* ===== Coming Soon Badge ===== */
.badge {
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
  background: var(--badge-bg);
  color: var(--badge-text);
  font-size: 0.875rem;
  font-weight: 600;
  padding: 0.5rem 1.25rem;
  border-radius: 2rem;
  margin-bottom: 1.25rem;
}

.badge-dot {
  width: 0.5rem;
  height: 0.5rem;
  background: var(--emerald-500);
  border-radius: 50%;
  animation: pulse 2s ease-in-out infinite;
}

@keyframes pulse {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(1.4); }
}

/* ===== Description ===== */
.description {
  font-size: 0.9375rem;
  color: var(--text-secondary);
  line-height: 1.7;
  margin-bottom: 2rem;
}

/* ===== Divider ===== */
.divider {
  height: 1px;
  background: var(--border-color);
  margin: 0 -0.5rem 1.75rem;
  opacity: 0.5;
}

/* ===== Form ===== */
.form-title {
  font-size: 1rem;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 1rem;
}

.form-group {
  display: flex;
  gap: 0.5rem;
  margin-bottom: 0.75rem;
}

.form-input {
  flex: 1;
  padding: 0.75rem 1rem;
  border: 1px solid var(--border-color);
  border-radius: 0.625rem;
  font-size: 0.9375rem;
  font-family: var(--font-family);
  color: var(--text-primary);
  background: var(--input-bg);
  outline: none;
  transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

.form-input::placeholder {
  color: var(--text-muted);
}

.form-input:focus {
  border-color: var(--emerald-500);
  box-shadow: 0 0 0 3px rgba(16, 185, 129, 0.15);
}

.form-btn {
  padding: 0.75rem 1.5rem;
  background: var(--emerald-500);
  color: #ffffff;
  border: none;
  border-radius: 0.625rem;
  font-size: 0.9375rem;
  font-weight: 600;
  font-family: var(--font-family);
  cursor: pointer;
  transition: background 0.2s ease, transform 0.1s ease;
  white-space: nowrap;
}

.form-btn:hover {
  background: var(--emerald-600);
}

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

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

.privacy-note {
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ===== Messages ===== */
.message {
  padding: 0.75rem 1rem;
  border-radius: 0.625rem;
  font-size: 0.875rem;
  margin-bottom: 1rem;
  display: none;
}

.message.show {
  display: block;
}

.message.success {
  background: var(--emerald-50);
  color: var(--emerald-700);
}

.message.error {
  background: #fef2f2;
  color: #dc2626;
}

@media (prefers-color-scheme: dark) {
  .message.success {
    background: rgba(16, 185, 129, 0.15);
    color: var(--emerald-400);
  }
  .message.error {
    background: rgba(239, 68, 68, 0.15);
    color: #f87171;
  }
}

/* ===== Features Preview ===== */
.features {
  display: flex;
  justify-content: center;
  gap: 2rem;
  margin-top: 2rem;
  padding-top: 1.5rem;
  border-top: 1px solid var(--border-color);
}

.feature {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 0.375rem;
}

.feature-icon {
  width: 2.25rem;
  height: 2.25rem;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--badge-bg);
  border-radius: 0.5rem;
  color: var(--emerald-500);
}

.feature-icon svg {
  width: 1.125rem;
  height: 1.125rem;
}

.feature-label {
  font-size: 0.6875rem;
  color: var(--text-muted);
  font-weight: 500;
  text-transform: uppercase;
  letter-spacing: 0.03em;
}

/* ===== Footer ===== */
.footer {
  margin-top: 2rem;
  text-align: center;
  font-size: 0.8125rem;
  color: var(--footer-text);
}

.footer a {
  color: var(--emerald-500);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.footer a:hover {
  color: var(--emerald-600);
}

.footer .copyright {
  margin-top: 0.5rem;
  font-size: 0.75rem;
  color: var(--text-muted);
}

/* ===== Responsive ===== */
@media (max-width: 480px) {
  .card {
    padding: 2rem 1.5rem;
    border-radius: 1.25rem;
  }

  .app-name {
    font-size: 1.875rem;
  }

  .form-group {
    flex-direction: column;
  }

  .form-btn {
    width: 100%;
  }

  .features {
    gap: 1.25rem;
  }

  .lang-switcher {
    top: 0.75rem;
    right: 0.75rem;
  }
}