:root {
  /* Centralized design tokens keep the neon palette and effects consistent. */
  color-scheme: dark;
  --bg: #05040d;
  --bg-2: #0c0a1f;
  --surface: rgba(16, 14, 36, 0.78);
  --surface-2: rgba(25, 21, 51, 0.9);
  --text: #f4ecff;
  --muted: #b8afd4;
  --primary: #2df8ff;
  --primary-hover: #6efbff;
  --accent: #ff2bd6;
  --accent-2: #a234ff;
  --border: rgba(136, 111, 255, 0.45);
  --success: #47ff9a;
  --danger: #ff6c97;
  --shadow: 0 0 0 1px rgba(188, 167, 255, 0.2), 0 20px 44px rgba(5, 2, 20, 0.55);
  --glow: 0 0 24px rgba(45, 248, 255, 0.35);
}

* {
  box-sizing: border-box;
}

body {
  /* Layered gradients create the ambient glow behind all content. */
  margin: 0;
  min-height: 100vh;
  font-family: "Inter", system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  color: var(--text);
  background:
    radial-gradient(circle at 10% 15%, rgba(255, 43, 214, 0.18), transparent 38%),
    radial-gradient(circle at 90% 0%, rgba(45, 248, 255, 0.16), transparent 35%),
    linear-gradient(135deg, var(--bg) 0%, var(--bg-2) 45%, #070611 100%);
  position: relative;
  overflow-x: hidden;
}

body::before {
  /* A subtle fixed grid overlays the page to reinforce the sci-fi theme. */
  content: "";
  position: fixed;
  inset: 0;
  pointer-events: none;
  background-image:
    linear-gradient(rgba(175, 149, 255, 0.09) 1px, transparent 1px),
    linear-gradient(90deg, rgba(175, 149, 255, 0.09) 1px, transparent 1px);
  background-size: 64px 64px;
  mask-image: radial-gradient(circle at center, black 45%, transparent 90%);
  z-index: -1;
}

.app-shell {
  width: min(1100px, 92vw);
  margin: 2.4rem auto 3rem;
  display: grid;
  gap: 1.5rem;
}

.hero {
  text-align: center;
  padding: 0.8rem 1rem;
}

.eyebrow {
  margin: 0;
  color: var(--primary);
  font-weight: 600;
  letter-spacing: 0.16em;
  text-transform: uppercase;
  font-size: 0.76rem;
  text-shadow: var(--glow);
}

h1 {
  margin: 0.35rem 0 0.75rem;
  font-size: clamp(1.8rem, 3.2vw, 2.6rem);
  letter-spacing: 0.02em;
  color: var(--primary);
  text-shadow: 0 0 20px rgba(255, 43, 214, 0.24);
}

.subtitle {
  max-width: 65ch;
  margin: 0 auto;
  color: var(--muted);
}

.panel {
  /* Shared card treatment for major content sections. */
  background: linear-gradient(155deg, rgba(23, 19, 48, 0.75), var(--surface));
  border: 1px solid var(--border);
  border-radius: 18px;
  box-shadow: var(--shadow);
  padding: 1.3rem;
  backdrop-filter: blur(6px);
}

.current-image-panel {
  display: grid;
  gap: 1rem;
}

.current-image {
  width: 100%;
  max-height: 430px;
  object-fit: cover;
  border-radius: 14px;
  border: 1px solid rgba(132, 225, 255, 0.45);
  background: #0b0920;
  box-shadow: 0 0 18px rgba(45, 248, 255, 0.22);
}

h2 {
  margin: 0;
  font-size: 1.2rem;
  color: #f5f3ff;
}

.input-row {
  display: flex;
  gap: 0.8rem;
  margin-top: 0.55rem;
}

input[type="email"] {
  flex: 1;
  border: 1px solid rgba(193, 170, 255, 0.5);
  background: rgba(7, 5, 22, 0.8);
  color: var(--text);
  border-radius: 10px;
  font: inherit;
  padding: 0.75rem 0.85rem;
}

input[type="email"]::placeholder {
  color: rgba(211, 199, 241, 0.62);
}

input[type="email"]:focus {
  /* Strong focus states improve keyboard accessibility and visibility. */
  outline: 2px solid color-mix(in srgb, var(--primary) 42%, transparent);
  border-color: var(--primary);
  box-shadow: 0 0 0 3px rgba(45, 248, 255, 0.14);
}

button {
  /* Base button behavior; variants below only override visual styling. */
  border: 0;
  border-radius: 10px;
  font: inherit;
  font-weight: 600;
  padding: 0.72rem 1rem;
  cursor: pointer;
  transition: transform 0.18s ease, box-shadow 0.18s ease, background 0.2s ease;
}

button:hover {
  transform: translateY(-1px);
}

.primary-btn {
  background: linear-gradient(90deg, var(--accent), var(--accent-2));
  color: #ffffff;
  box-shadow: 0 0 22px rgba(255, 43, 214, 0.28);
}

.primary-btn:hover {
  box-shadow: 0 0 26px rgba(255, 43, 214, 0.42);
}

.secondary-btn {
  justify-self: start;
  background: rgba(24, 23, 46, 0.95);
  color: var(--primary);
  border: 1px solid rgba(45, 248, 255, 0.42);
  box-shadow: inset 0 0 10px rgba(45, 248, 255, 0.15);
}

.secondary-btn:hover {
  background: rgba(28, 30, 59, 0.95);
  box-shadow: inset 0 0 14px rgba(45, 248, 255, 0.24), 0 0 20px rgba(45, 248, 255, 0.2);
}

.form-message {
  min-height: 1.2em;
  margin: 0.7rem 0 0;
  font-weight: 500;
}

.form-message.error {
  color: var(--danger);
}

.form-message.success {
  color: var(--success);
}

.results-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  gap: 0.8rem;
}

.count-pill {
  display: inline-flex;
  padding: 0.3rem 0.65rem;
  border-radius: 999px;
  background: rgba(34, 30, 70, 0.95);
  color: var(--primary);
  border: 1px solid rgba(45, 248, 255, 0.3);
  font-weight: 600;
  font-size: 0.85rem;
}

.assignments-grid {
  /* Responsive auto-fit keeps result cards balanced as width changes. */
  margin-top: 1rem;
  display: grid;
  gap: 1rem;
  grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
}

.email-card {
  border: 1px solid rgba(122, 101, 220, 0.55);
  border-radius: 14px;
  padding: 0.9rem;
  background: linear-gradient(165deg, rgba(29, 24, 58, 0.92), var(--surface-2));
  box-shadow: inset 0 0 0 1px rgba(255, 255, 255, 0.03);
}

.email-card h3 {
  margin: 0 0 0.4rem;
  font-size: 1rem;
  overflow-wrap: anywhere;
  color: #f8f4ff;
}

.image-count {
  margin: 0 0 0.7rem;
  color: rgba(208, 196, 238, 0.85);
  font-size: 0.9rem;
}

.thumb-grid {
  display: grid;
  grid-template-columns: repeat(2, minmax(0, 1fr));
  gap: 0.5rem;
}

.thumb-grid img {
  width: 100%;
  height: 92px;
  object-fit: cover;
  border-radius: 8px;
  border: 1px solid rgba(182, 165, 239, 0.45);
}

.empty-state {
  color: var(--muted);
  margin: 0;
}

@media (max-width: 680px) {
  /* Stack controls on narrow screens for easier tapping and reading. */
  .app-shell {
    margin: 1.4rem auto 2rem;
  }

  .input-row {
    flex-direction: column;
  }

  .primary-btn {
    width: 100%;
  }
}