/* ============ GLOBAL ============ */
[hidden] { display: none !important; }

/* ============ DESIGN TOKENS ============ */
:root,
[data-theme='light'] {
  --text-xs: clamp(0.75rem, 0.7rem + 0.25vw, 0.875rem);
  --text-sm: clamp(0.875rem, 0.8rem + 0.35vw, 1rem);
  --text-base: clamp(1rem, 0.95rem + 0.25vw, 1.125rem);
  --text-lg: clamp(1.125rem, 1rem + 0.75vw, 1.5rem);
  --text-xl: clamp(1.5rem, 1.2rem + 1.25vw, 2.25rem);
  --text-2xl: clamp(2rem, 1.2rem + 2.5vw, 3.5rem);

  --space-1: 0.25rem;
  --space-2: 0.5rem;
  --space-3: 0.75rem;
  --space-4: 1rem;
  --space-5: 1.25rem;
  --space-6: 1.5rem;
  --space-8: 2rem;
  --space-10: 2.5rem;
  --space-12: 3rem;
  --space-16: 4rem;
  --space-20: 5rem;
  --space-24: 6rem;

  /* Light mode - warm purple/violet brand */
  --color-bg: #fafaff;
  --color-surface: #ffffff;
  --color-surface-2: #f3f1ff;
  --color-border: #e4e1f5;
  --color-divider: #ecebf7;
  --color-text: #1e1b4b;
  --color-text-muted: #4c4d75;
  --color-text-faint: #9c9bc6;

  --color-primary: #7c3aed;
  --color-primary-hover: #6d28d9;
  --color-primary-active: #5b21b6;
  --color-primary-soft: #ede9fe;

  --color-success: #16a34a;
  --color-success-soft: #dcfce7;
  --color-error: #dc2626;
  --color-error-soft: #fee2e2;

  --radius-sm: 0.5rem;
  --radius-md: 0.75rem;
  --radius-lg: 1rem;
  --radius-xl: 1.5rem;
  --radius-full: 9999px;

  --shadow-sm: 0 1px 2px rgb(30 27 75 / 0.05);
  --shadow-md: 0 4px 16px rgb(30 27 75 / 0.06);
  --shadow-lg: 0 20px 48px rgb(30 27 75 / 0.12);
  --shadow-glow: 0 0 0 4px rgb(124 58 237 / 0.15);

  --transition: 200ms cubic-bezier(0.16, 1, 0.3, 1);

  --font-body: 'Space Grotesk', system-ui, -apple-system, sans-serif;
  --font-mono: 'JetBrains Mono', ui-monospace, monospace;

  --content-narrow: 720px;
  --content-default: 1080px;
}

[data-theme='dark'] {
  --color-bg: #0b0a1a;
  --color-surface: #14132a;
  --color-surface-2: #1c1a3a;
  --color-border: #2d2a55;
  --color-divider: #1f1d40;
  --color-text: #e8e7ff;
  --color-text-muted: #a5a3cc;
  --color-text-faint: #6c6b95;
  --color-primary: #a78bfa;
  --color-primary-hover: #c4b5fd;
  --color-primary-active: #ddd6fe;
  --color-primary-soft: #2e1f5e;
  --color-success: #4ade80;
  --color-success-soft: #14532d;
  --color-error: #f87171;
  --color-error-soft: #4c1717;
  --shadow-sm: 0 1px 2px rgb(0 0 0 / 0.3);
  --shadow-md: 0 4px 16px rgb(0 0 0 / 0.35);
  --shadow-lg: 0 20px 48px rgb(0 0 0 / 0.5);
  --shadow-glow: 0 0 0 4px rgb(167 139 250 / 0.18);
}

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

html {
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
  scroll-behavior: smooth;
}

body {
  min-height: 100dvh;
  line-height: 1.6;
  font-family: var(--font-body);
  font-size: var(--text-base);
  color: var(--color-text);
  background: var(--color-bg);
  transition: background var(--transition), color var(--transition);
}

img, svg { display: block; max-width: 100%; }

h1, h2, h3 { line-height: 1.15; text-wrap: balance; font-weight: 700; }
p { text-wrap: pretty; }

button {
  cursor: pointer;
  background: none;
  border: none;
  font: inherit;
  color: inherit;
}

a {
  color: var(--color-primary);
  text-decoration: none;
  font-weight: 500;
  transition: color var(--transition);
}
a:hover { color: var(--color-primary-hover); }

:focus-visible {
  outline: 2px solid var(--color-primary);
  outline-offset: 3px;
  border-radius: var(--radius-sm);
}

::selection {
  background: var(--color-primary-soft);
  color: var(--color-text);
}

/* ============ LAYOUT ============ */
.container {
  width: 100%;
  max-width: var(--content-default);
  margin-inline: auto;
  padding-inline: var(--space-6);
}

/* ============ HEADER ============ */
.header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: color-mix(in srgb, var(--color-bg) 88%, transparent);
  backdrop-filter: saturate(180%) blur(12px);
  -webkit-backdrop-filter: saturate(180%) blur(12px);
  border-bottom: 1px solid var(--color-divider);
}

.header-inner {
  display: flex;
  align-items: center;
  justify-content: space-between;
  padding-block: var(--space-4);
}

.logo {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-text);
  font-weight: 700;
  font-size: var(--text-base);
}

.logo svg { color: var(--color-primary); }

.theme-toggle {
  width: 40px;
  height: 40px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  border-radius: var(--radius-full);
  color: var(--color-text-muted);
  transition: background var(--transition), color var(--transition);
}
.theme-toggle:hover {
  background: var(--color-surface-2);
  color: var(--color-text);
}

/* ============ HERO ============ */
.hero {
  padding-block: clamp(var(--space-10), 6vw, var(--space-20));
  text-align: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  inset: 0;
  background:
    radial-gradient(ellipse 60% 50% at 50% 0%, color-mix(in srgb, var(--color-primary) 10%, transparent), transparent 70%);
  pointer-events: none;
  z-index: -1;
}

.hero h1 {
  font-size: var(--text-2xl);
  letter-spacing: -0.025em;
  margin-bottom: var(--space-3);
}

.hero-sub {
  font-size: var(--text-lg);
  color: var(--color-text-muted);
  max-width: 580px;
  margin: 0 auto var(--space-10);
}

/* ============ EMAIL CARD ============ */
.email-card {
  max-width: 580px;
  margin: 0 auto;
  background: var(--color-surface);
  border: 1.5px solid var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-6) var(--space-6);
  box-shadow: var(--shadow-md);
  text-align: left;
  position: relative;
  overflow: hidden;
}

.email-card::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, var(--color-primary), color-mix(in srgb, var(--color-primary) 50%, transparent));
}

.email-loading {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: var(--space-3);
  padding: var(--space-6) 0;
  color: var(--color-text-muted);
}

.spinner-large {
  width: 32px;
  height: 32px;
  border: 3px solid var(--color-border);
  border-top-color: var(--color-primary);
  border-radius: var(--radius-full);
  animation: spin 0.8s linear infinite;
}

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

.email-label {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 600;
  margin-bottom: var(--space-2);
}

.email-address-row {
  display: flex;
  align-items: center;
  gap: var(--space-3);
  flex-wrap: wrap;
}

.email-address {
  flex: 1 1 200px;
  font-family: var(--font-mono);
  font-size: var(--text-lg);
  font-weight: 600;
  color: var(--color-primary);
  background: var(--color-primary-soft);
  padding: var(--space-3) var(--space-4);
  border-radius: var(--radius-md);
  word-break: break-all;
  min-width: 0;
  letter-spacing: -0.01em;
}

.copy-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  padding: var(--space-3) var(--space-4);
  background: var(--color-primary);
  color: white;
  border-radius: var(--radius-md);
  font-weight: 600;
  font-size: var(--text-sm);
  transition: background var(--transition), transform var(--transition);
}

.copy-btn:hover {
  background: var(--color-primary-hover);
}
.copy-btn:active { transform: scale(0.97); }
.copy-btn.copied {
  background: var(--color-success);
}

.email-meta {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-3);
  margin-top: var(--space-4);
  padding-top: var(--space-4);
  border-top: 1px solid var(--color-divider);
  flex-wrap: wrap;
}

.meta-item {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.meta-item svg { color: var(--color-success); }

.link-btn {
  display: inline-flex;
  align-items: center;
  gap: var(--space-2);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  font-weight: 500;
  padding: var(--space-2) var(--space-3);
  border-radius: var(--radius-md);
  transition: background var(--transition), color var(--transition);
}

.link-btn:hover {
  background: var(--color-surface-2);
  color: var(--color-primary);
}

/* ============ INBOX ============ */
.inbox-section {
  max-width: 580px;
  margin: var(--space-8) auto 0;
  text-align: left;
  animation: slideUp 0.4s cubic-bezier(0.16, 1, 0.3, 1);
}

@keyframes slideUp {
  from { opacity: 0; transform: translateY(8px); }
  to { opacity: 1; transform: translateY(0); }
}

.inbox-header {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  margin-bottom: var(--space-4);
}

.inbox-header h2 {
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.inbox-count {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  font-family: var(--font-mono);
}

.inbox-empty {
  background: var(--color-surface);
  border: 1.5px dashed var(--color-border);
  border-radius: var(--radius-lg);
  padding: var(--space-10) var(--space-6);
  text-align: center;
}

.empty-icon {
  color: var(--color-text-faint);
  margin: 0 auto var(--space-4);
  width: 56px;
  height: 56px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface-2);
  border-radius: var(--radius-full);
}

.empty-title {
  font-size: var(--text-base);
  font-weight: 600;
  color: var(--color-text);
  margin-bottom: var(--space-2);
}

.empty-sub {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  max-width: 380px;
  margin: 0 auto;
}

.message-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.message-item {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: var(--space-4) var(--space-5);
  cursor: pointer;
  transition: border-color var(--transition), transform var(--transition), box-shadow var(--transition);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
}

.message-item:hover {
  border-color: var(--color-primary);
  box-shadow: var(--shadow-sm);
}

.message-item.unread {
  border-left: 3px solid var(--color-primary);
}

.message-top {
  display: flex;
  align-items: baseline;
  justify-content: space-between;
  gap: var(--space-3);
}

.message-from {
  font-weight: 600;
  font-size: var(--text-sm);
  color: var(--color-text);
  flex: 1;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.message-time {
  font-size: var(--text-xs);
  color: var(--color-text-faint);
  font-family: var(--font-mono);
  flex-shrink: 0;
}

.message-subject {
  font-size: var(--text-sm);
  color: var(--color-text);
  font-weight: 500;
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

.message-preview {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  overflow: hidden;
  text-overflow: ellipsis;
  white-space: nowrap;
}

/* ============ HOW IT WORKS ============ */
.how-it-works {
  padding-block: clamp(var(--space-12), 8vw, var(--space-20));
  background: var(--color-surface-2);
  border-top: 1px solid var(--color-divider);
  border-bottom: 1px solid var(--color-divider);
}

.how-it-works h2 {
  text-align: center;
  font-size: var(--text-xl);
  margin-bottom: var(--space-10);
  letter-spacing: -0.02em;
}

.steps-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(260px, 1fr));
  gap: var(--space-6);
}

.step {
  background: var(--color-surface);
  padding: var(--space-6);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  position: relative;
}

.step-num {
  width: 36px;
  height: 36px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary);
  color: white;
  border-radius: var(--radius-full);
  font-weight: 700;
  font-size: var(--text-base);
  margin-bottom: var(--space-3);
  font-family: var(--font-mono);
}

.step h3 {
  font-size: var(--text-base);
  font-weight: 600;
  margin-bottom: var(--space-2);
  letter-spacing: -0.01em;
}

.step p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ============ FEATURES ============ */
.features {
  padding-block: clamp(var(--space-12), 8vw, var(--space-20));
}

.features-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(220px, 1fr));
  gap: var(--space-6);
}

.feature {
  display: flex;
  flex-direction: column;
  gap: var(--space-2);
}

.feature-icon {
  width: 44px;
  height: 44px;
  display: inline-flex;
  align-items: center;
  justify-content: center;
  background: var(--color-primary-soft);
  color: var(--color-primary);
  border-radius: var(--radius-md);
  margin-bottom: var(--space-2);
}

.feature h3 {
  font-size: var(--text-lg);
  font-weight: 600;
  letter-spacing: -0.01em;
}

.feature p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

/* ============ FAQ ============ */
.faq {
  padding-block: clamp(var(--space-12), 8vw, var(--space-20));
  background: var(--color-surface-2);
  border-top: 1px solid var(--color-divider);
}

.faq .container {
  max-width: var(--content-narrow);
}

.faq h2 {
  font-size: var(--text-xl);
  margin-bottom: var(--space-8);
  letter-spacing: -0.02em;
}

.faq details {
  border-bottom: 1px solid var(--color-divider);
  padding-block: var(--space-5);
}

.faq summary {
  font-size: var(--text-base);
  font-weight: 600;
  cursor: pointer;
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: var(--space-4);
  color: var(--color-text);
}

.faq summary::-webkit-details-marker { display: none; }

.faq summary::after {
  content: '+';
  font-size: 1.5rem;
  font-weight: 400;
  color: var(--color-text-muted);
  transition: transform var(--transition);
  flex-shrink: 0;
}

.faq details[open] summary::after {
  content: '–';
}

.faq details p {
  margin-top: var(--space-3);
  color: var(--color-text-muted);
  font-size: var(--text-sm);
  line-height: 1.7;
}

/* ============ FOOTER ============ */
.footer {
  padding-block: var(--space-10);
  border-top: 1px solid var(--color-divider);
  background: var(--color-surface);
}

.footer-inner { text-align: center; }

.footer p {
  font-size: var(--text-sm);
  color: var(--color-text-muted);
}

.footer-sub {
  color: var(--color-text-faint);
  margin-top: var(--space-1);
  font-size: var(--text-xs);
}

/* ============ MODAL ============ */
.modal[hidden] { display: none !important; }
.modal {
  position: fixed;
  inset: 0;
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--space-4);
  animation: fadeIn 0.2s ease-out;
}

@keyframes fadeIn { from { opacity: 0; } to { opacity: 1; } }

.modal-backdrop {
  position: absolute;
  inset: 0;
  background: color-mix(in srgb, var(--color-text) 50%, transparent);
  backdrop-filter: blur(4px);
}

.modal-panel {
  position: relative;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-lg);
  max-width: 640px;
  width: 100%;
  max-height: 80vh;
  display: flex;
  flex-direction: column;
  overflow: hidden;
}

.modal-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: var(--space-4);
  padding: var(--space-5) var(--space-6);
  border-bottom: 1px solid var(--color-divider);
}

.modal-header h3 {
  font-size: var(--text-base);
  font-weight: 600;
  line-height: 1.4;
}

.modal-close {
  color: var(--color-text-muted);
  flex-shrink: 0;
  padding: var(--space-1);
  margin: calc(var(--space-1) * -1);
  border-radius: var(--radius-sm);
  transition: color var(--transition), background var(--transition);
}
.modal-close:hover {
  color: var(--color-text);
  background: var(--color-surface-2);
}

.modal-meta {
  padding: var(--space-4) var(--space-6);
  background: var(--color-surface-2);
  font-size: var(--text-sm);
  color: var(--color-text-muted);
  display: flex;
  flex-direction: column;
  gap: var(--space-1);
  border-bottom: 1px solid var(--color-divider);
}

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

.modal-body {
  padding: var(--space-6);
  overflow-y: auto;
  font-size: var(--text-sm);
  line-height: 1.7;
  color: var(--color-text);
}

.modal-body p { margin-bottom: var(--space-3); }
.modal-body a { word-break: break-all; }

/* ============ RESPONSIVE ============ */
@media (max-width: 540px) {
  .email-address {
    font-size: var(--text-base);
  }
  .email-address-row {
    flex-direction: column;
    align-items: stretch;
  }
  .copy-btn {
    width: 100%;
    justify-content: center;
  }
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-duration: 0.01ms !important;
    transition-duration: 0.01ms !important;
  }
}