/* ============================================================
      WHY: Custom CSS only where Tailwind can't help —
      gradients, backgrounds, and special component styles
    ============================================================ */

body {
  font-family: "DM Sans", sans-serif;
  /* WHY: Dark radial gradient gives a clinical "scan room" feel
         — atmospheric without being distracting */
  background: radial-gradient(
    ellipse at top,
    #1a3260 0%,
    #0f1f3d 50%,
    #080f1e 100%
  );
  min-height: 100vh;
}

/* WHY: The brain SVG in the hero is purely decorative atmosphere */
.brain-bg {
  position: absolute;
  opacity: 0.04;
  width: 600px;
  height: 600px;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  pointer-events: none;
}

/* WHY: Glass morphism card — frosted glass over dark background
       creates depth and a modern medical-dashboard aesthetic */
.glass-card {
  background: rgba(255, 255, 255, 0.04);
  backdrop-filter: blur(12px);
  border: 1px solid rgba(255, 255, 255, 0.08);
}

/* WHY: Section cards for each form group — lighter glass panels
       visually group related fields (like a medical form sections) */
.form-section {
  background: rgba(255, 255, 255, 0.03);
  border: 1px solid rgba(255, 255, 255, 0.07);
  border-radius: 16px;
  padding: 28px;
  margin-bottom: 20px;
}

/* WHY: Custom input styling — dark inputs with teal focus ring
       matches our palette and feels like medical software */
.form-input {
  width: 100%;
  background: rgba(255, 255, 255, 0.06);
  border: 1px solid rgba(255, 255, 255, 0.12);
  border-radius: 10px;
  padding: 10px 14px;
  color: #e2e8f0;
  font-family: "DM Sans", sans-serif;
  font-size: 14px;
  transition: all 0.2s ease;
  outline: none;
}
.form-input:focus {
  border-color: #0d9488;
  box-shadow: 0 0 0 3px rgba(13, 148, 136, 0.15);
  background: rgba(255, 255, 255, 0.09);
}
.form-input option {
  background: #1a3260;
  color: #e2e8f0;
}

/* WHY: Labels styled for dark background — muted but readable */
.form-label {
  display: block;
  font-size: 12px;
  font-weight: 500;
  color: #94a3b8;
  margin-bottom: 6px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* WHY: Range sliders need custom CSS — Tailwind doesn't style these */
input[type="range"] {
  -webkit-appearance: none;
  width: 100%;
  height: 6px;
  border-radius: 4px;
  background: rgba(255, 255, 255, 0.1);
  outline: none;
}
input[type="range"]::-webkit-slider-thumb {
  -webkit-appearance: none;
  width: 18px;
  height: 18px;
  border-radius: 50%;
  background: #0d9488;
  cursor: pointer;
  box-shadow: 0 0 8px rgba(13, 148, 136, 0.6);
  transition: transform 0.15s;
}
input[type="range"]::-webkit-slider-thumb:hover {
  transform: scale(1.2);
}

/* WHY: Toggle switches for Yes/No fields — much better UX
       than a dropdown for binary choices in a medical form */
.toggle-group {
  display: flex;
  gap: 8px;
}
.toggle-btn {
  flex: 1;
  padding: 9px;
  border-radius: 8px;
  border: 1px solid rgba(255, 255, 255, 0.1);
  background: rgba(255, 255, 255, 0.04);
  color: #94a3b8;
  font-size: 13px;
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  text-align: center;
}
.toggle-btn:hover {
  background: rgba(255, 255, 255, 0.08);
}
.toggle-btn.active-yes {
  background: rgba(13, 148, 136, 0.2);
  border-color: #0d9488;
  color: #5eead4;
}
.toggle-btn.active-no {
  background: rgba(255, 255, 255, 0.08);
  border-color: rgba(255, 255, 255, 0.25);
  color: #e2e8f0;
}

/* WHY: Section heading with teal left border — clear visual
       hierarchy that guides the doctor filling the form */
.section-title {
  font-family: "DM Serif Display", serif;
  font-size: 18px;
  color: #e2e8f0;
  margin-bottom: 20px;
  padding-left: 12px;
  border-left: 3px solid #0d9488;
}

/* WHY: The predict button is the primary CTA —
       teal gradient, glow on hover, scale on click */
.predict-btn {
  width: 100%;
  padding: 18px;
  background: linear-gradient(135deg, #0d9488, #14b8a6);
  border: none;
  border-radius: 14px;
  color: white;
  font-family: "DM Sans", sans-serif;
  font-size: 16px;
  font-weight: 600;
  letter-spacing: 0.03em;
  cursor: pointer;
  transition: all 0.3s ease;
  box-shadow: 0 4px 24px rgba(13, 148, 136, 0.35);
}
.predict-btn:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px rgba(13, 148, 136, 0.5);
}
.predict-btn:active {
  transform: translateY(0);
}
.predict-btn:disabled {
  opacity: 0.6;
  cursor: not-allowed;
  transform: none;
}

/* WHY: Result panel appears after prediction —
       color-coded (red=sick, green=healthy) for instant clarity */
.result-panel {
  display: none;
  border-radius: 16px;
  padding: 32px;
  margin-top: 24px;
  animation: fadeUp 0.5s ease forwards;
  text-align: center;
}
.result-panel.show {
  display: block;
}
.result-positive {
  background: rgba(239, 68, 68, 0.1);
  border: 1px solid rgba(239, 68, 68, 0.3);
}
.result-negative {
  background: rgba(13, 148, 136, 0.1);
  border: 1px solid rgba(13, 148, 136, 0.3);
}

/* WHY: Staggered animation delays for section cards —
       they fade up one by one on page load, feels polished */
.section-animate {
  opacity: 0;
  animation: fadeUp 0.6s ease forwards;
}
.section-animate:nth-child(1) {
  animation-delay: 0.1s;
}
.section-animate:nth-child(2) {
  animation-delay: 0.2s;
}
.section-animate:nth-child(3) {
  animation-delay: 0.3s;
}
.section-animate:nth-child(4) {
  animation-delay: 0.4s;
}
.section-animate:nth-child(5) {
  animation-delay: 0.5s;
}
.section-animate:nth-child(6) {
  animation-delay: 0.6s;
}
.section-animate:nth-child(7) {
  animation-delay: 0.7s;
}

/* WHY: Loading spinner shown while waiting for API response */
.spinner {
  display: inline-block;
  width: 20px;
  height: 20px;
  border: 2px solid rgba(255, 255, 255, 0.3);
  border-top-color: white;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}
@keyframes spin {
  to {
    transform: rotate(360deg);
  }
}

/* WHY: Confidence bar — visual representation of model certainty */
.confidence-bar-track {
  height: 8px;
  background: rgba(255, 255, 255, 0.1);
  border-radius: 4px;
  overflow: hidden;
  margin-top: 8px;
}
.confidence-bar-fill {
  height: 100%;
  border-radius: 4px;
  transition: width 1s ease;
}