:root {
  /* -- Palette -- */
  --bg-gradient-start: #0f172a;
  /* Slate 900 */
  --bg-gradient-end: #1e293b;
  /* Slate 800 */

  --color-brand-primary: #0ea5e9;
  /* Sky 500 */
  --color-brand-secondary: #3b82f6;
  /* Blue 500 */
  --color-accent: #38bdf8;
  /* Sky 400 */

  --color-surface-card: rgba(30, 41, 59, 0.7);
  --color-surface-input: rgba(15, 23, 42, 0.6);
  --color-surface-hover: rgba(56, 189, 248, 0.05);

  --color-text-main: #f8fafc;
  /* Slate 50 */
  --color-text-muted: #94a3b8;
  /* Slate 400 */

  --color-border: rgba(148, 163, 184, 0.1);
  --color-border-active: rgba(14, 165, 233, 0.5);
  --color-border-error: #ef4444;

  --color-success: #22c55e;
  --color-warning: #f59e0b;
  --color-danger: #ef4444;

  --shadow-glass: 0 8px 32px 0 rgba(0, 0, 0, 0.37);
  --shadow-sm: 0 1px 2px 0 rgba(0, 0, 0, 0.05);
  --shadow-lg: 0 10px 15px -3px rgba(0, 0, 0, 0.1);

  --font-main: 'Outfit', sans-serif;
  --radius-lg: 1rem;
  --radius-md: 0.75rem;
  --radius-sm: 0.5rem;

  --transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

[data-theme="light"] {
  --bg-gradient-start: #f8fafc;
  --bg-gradient-end: #e2e8f0;

  --color-surface-card: rgba(255, 255, 255, 0.85);
  --color-surface-input: #ffffff;
  --color-surface-hover: rgba(14, 165, 233, 0.05);

  --color-text-main: #0f172a;
  --color-text-muted: #64748b;

  --color-border: rgba(203, 213, 225, 0.6);
  --shadow-glass: 0 8px 32px 0 rgba(148, 163, 184, 0.15);
}

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

body {
  font-family: var(--font-main);
  background: radial-gradient(circle at top left, var(--bg-gradient-start), var(--bg-gradient-end));
  background-attachment: fixed;
  color: var(--color-text-main);
  margin: 0;
  padding: 2rem 1rem;
  min-height: 100vh;
  display: flex;
  justify-content: center;
  line-height: 1.5;
}

/* -- Background Ambiance -- */
.background-orb {
  position: fixed;
  top: -10%;
  left: -10%;
  width: 50vw;
  height: 50vw;
  border-radius: 50%;
  background: radial-gradient(circle, rgba(56, 189, 248, 0.15), transparent 70%);
  filter: blur(80px);
  z-index: -1;
  pointer-events: none;
}

/* -- Layout Components -- */
.main-container {
  max-width: 1000px;
  width: 100%;
  border-radius: var(--radius-lg);
  position: relative;
}

.glass-panel {
  background: var(--color-surface-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-glass);
  border-radius: var(--radius-lg);
  overflow: hidden;
}

/* -- Header -- */
.app-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin: 0 auto 2rem auto;
  padding: 1.5rem;
  max-width: 800px;
  width: 100%;
}

.logo-area h1 {
  font-size: 1.8rem;
  font-weight: 700;
  margin: 0;
  background: linear-gradient(135deg, var(--color-text-main) 0%, var(--color-text-muted) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

[data-theme="dark"] .logo-area h1 {
  background: linear-gradient(135deg, #fff 0%, #94a3b8 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}

.logo-area p {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-top: 0.2rem;
}

/* -- Form Grid (Single Column Stack) -- */
.layout-grid {
  display: flex;
  flex-direction: column;
  gap: 2rem;
  max-width: 800px;
  /* Constrain width for readability now that it's stacked */
  margin: 0 auto;
  /* Center it */
}

.form-section {
  padding: 2rem;
}

/* ... */

/* -- Sidebar / Results -- */
.sidebar {
  /* No longer sticky or side-by-side */
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
  width: 100%;
}

.input-grid {
  display: grid;
  grid-template-columns: repeat(2, 1fr);
  gap: 1.5rem;
  margin-bottom: 1.5rem;
}

.input-column {
  display: flex;
  flex-direction: column;
  gap: 1.5rem;
}

.input-group {
  display: flex;
  flex-direction: column;
  gap: 0.5rem;
}

.input-group label {
  font-size: 0.85rem;
  font-weight: 600;
  color: var(--color-text-muted);
  text-transform: uppercase;
  letter-spacing: 0.03em;
  display: flex;
  align-items: center;
  gap: 0.5rem;
}

.label-icon {
  font-size: 1rem;
  opacity: 0.8;
}

.field-wrapper {
  position: relative;
  display: flex;
  align-items: center;
}

input[type="text"],
input[type="number"],
select {
  width: 100%;
  padding: 0.8rem 1rem;
  font-family: var(--font-main);
  font-size: 1rem;
  color: var(--color-text-main);
  background: var(--color-surface-input);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  transition: var(--transition);
}

input[type="text"]:focus,
select:focus {
  outline: none;
  border-color: var(--color-brand-primary);
  box-shadow: 0 0 0 3px rgba(14, 165, 233, 0.15);
  background: rgba(15, 23, 42, 0.8);
}

.field-suffix {
  position: absolute;
  right: 1rem;
  color: var(--color-text-muted);
  font-size: 0.85rem;
  pointer-events: none;
}

/* Padded Input for Suffix */
input.has-suffix {
  padding-right: 3.5rem;
}

/* Select styling */
select {
  appearance: none;
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' fill='none' viewBox='0 0 24 24' stroke='%2394a3b8'%3E%3Cpath stroke-linecap='round' stroke-linejoin='round' stroke-width='2' d='M19 9l-7 7-7-7'%3E%3C/path%3E%3C/svg%3E");
  background-repeat: no-repeat;
  background-position: right 1rem center;
  background-size: 1rem;
  padding-right: 2.5rem;
}

/* Ref Inputs (Small ULN/LLN) */
.ref-input-wrapper {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-left: auto;
}

.ref-label {
  font-size: 0.7rem;
  font-weight: 600;
  color: var(--color-text-muted);
  background: rgba(255, 255, 255, 0.05);
  padding: 2px 6px;
  border-radius: 4px;
}

.ref-input {
  width: 70px !important;
  padding: 0.3rem 0.5rem !important;
  font-size: 0.8rem !important;
  height: auto;
  text-align: center;
}

/* -- Buttons -- */
.btn-primary {
  width: 100%;
  padding: 1rem;
  background: linear-gradient(135deg, var(--color-brand-primary) 0%, var(--color-brand-secondary) 100%);
  color: #fff;
  font-weight: 600;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: var(--transition);
  margin-top: 1.5rem;
  box-shadow: 0 4px 12px rgba(14, 165, 233, 0.2);
}

.btn-primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 20px rgba(14, 165, 233, 0.3);
}

.btn-secondary {
  width: 100%;
  padding: 1rem;
  background: rgba(14, 165, 233, 0.1);
  border: 1px solid var(--color-brand-primary);
  color: var(--color-brand-primary);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-weight: 600;
  text-transform: uppercase;
  letter-spacing: 0.05em;
  transition: var(--transition);
  margin-top: 1.5rem;
}

.btn-secondary:hover {
  background: rgba(14, 165, 233, 0.2);
  color: var(--color-text-main);
  transform: translateY(-2px);
}

.action-buttons {
  display: flex;
  gap: 1rem;
  margin-top: 2rem;
}

/* -- Accordion -- */
.accordion-item {
  background: rgba(0, 0, 0, 0.1);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
  margin-bottom: 1rem;
}

.accordion-header {
  width: 100%;
  padding: 1rem;
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: transparent;
  cursor: pointer;
  color: var(--color-text-main);
  font-weight: 600;
  user-select: none;
}

.accordion-header:hover {
  background: var(--color-surface-hover);
}

.accordion-content {
  display: none;
  padding: 1rem;
  border-top: 1px solid var(--color-border);
}

.accordion-content.active {
  display: block;
}

.accordion-header.active .chevron {
  transform: rotate(180deg);
}




.result-card-container {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
  /* Responsive 2-column */
  gap: 1.5rem;
  padding: 0;
  border-top: 4px solid transparent;
  width: 100%;
}

/* MELD Highlighting */
.meld-card {
  border-top-color: var(--color-brand-primary);
  text-align: center;
  padding: 2rem 1.5rem;
}

.result-value-large {
  font-size: 3.5rem;
  font-weight: 700;
  line-height: 1;
  margin: 0.5rem 0;
  color: var(--color-text-main);
}

.result-subtitle {
  color: var(--color-text-muted);
  font-size: 0.9rem;
  margin-bottom: 1.5rem;
}

/* -- Severity Bar -- */
.severity-container {
  position: relative;
  margin-top: 1rem;
  width: 100%;
}

.severity-bar-bg {
  height: 12px;
  width: 100%;
  background: linear-gradient(90deg,
      #22c55e 0%,
      #eab308 50%,
      #ef4444 100%);
  border-radius: 6px;
  position: relative;
  box-shadow: inset 0 2px 4px rgba(0, 0, 0, 0.2);
}

.severity-marker {
  position: absolute;
  top: -4px;
  left: 0%;
  /* Dynamic */
  width: 6px;
  height: 20px;
  background: #fff;
  border-radius: 3px;
  box-shadow: 0 0 6px rgba(0, 0, 0, 0.5);
  transform: translateX(-50%);
  transition: left 0.5s cubic-bezier(0.34, 1.56, 0.64, 1);
}

.severity-labels {
  display: flex;
  justify-content: space-between;
  font-size: 0.75rem;
  color: var(--color-text-muted);
  margin-top: 0.5rem;
  font-weight: 600;
}

/* -- Other Results (Standard) -- */
/* -- Scrollbar -- */
::-webkit-scrollbar {
  width: 10px;
}

::-webkit-scrollbar-track {
  background: var(--bg-gradient-end);
}

::-webkit-scrollbar-thumb {
  background: var(--color-surface-card);
  border-radius: 5px;
  border: 1px solid var(--color-border);
}

::-webkit-scrollbar-thumb:hover {
  background: var(--color-brand-primary);
}

/* -- Other Results -- */
.result-card {
  padding: 1.5rem;
  /* margin-bottom handled by grid gap */
  background: var(--color-surface-card);
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border: 1px solid var(--color-border);
  box-shadow: var(--shadow-glass);
  border-radius: var(--radius-lg);
  position: relative;
  overflow: hidden;
}

.risk-low {
  border-left-color: var(--color-success);
  background: rgba(34, 197, 94, 0.1);
}

.risk-medium {
  border-left-color: var(--color-warning);
  background: rgba(245, 158, 11, 0.1);
}

.risk-high {
  border-left-color: var(--color-danger);
  background: rgba(239, 68, 68, 0.1);
}


/* -- Controls (Theme/Lang) -- */
.controls-area {
  display: flex;
  gap: 0.5rem;
}

.control-btn {
  width: 40px;
  height: 40px;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--color-surface-input);
  border: 1px solid var(--color-border);
  color: var(--color-text-main);
  border-radius: 50%;
  cursor: pointer;
  transition: var(--transition);
}

.control-btn:hover {
  border-color: var(--color-accent);
  transform: scale(1.05);
}

/* -- Utilities -- */
.hidden {
  display: none;
}

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

.mt-2 {
  margin-top: 0.5rem;
}

/* -- Responsive -- */
@media (max-width: 900px) {
  .layout-grid {
    grid-template-columns: 1fr;
  }

  .main-container {
    padding-bottom: 5rem;
    /* Space for FAB or scrolling */
  }

  .sidebar {
    position: static;
    order: -1;
  }
}

@media (max-width: 600px) {
  .input-grid {
    grid-template-columns: 1fr;
  }

  .app-header {
    flex-direction: column;
    align-items: flex-start;
    gap: 1rem;
  }

  .controls-area {
    align-self: flex-end;
  }
}

/* -- Result Symbols -- */
.baveno-symbols,
.fib4-interpreter {
  margin-top: 0.5rem;
  padding: 0.5rem;
  background: rgba(0, 0, 0, 0.2);
  border-radius: var(--radius-sm);
  font-size: 0.9rem;
}

.symbol {
  font-weight: bold;
  display: inline-block;
  width: 1.2em;
  text-align: center;
}

.symbol.green {
  color: var(--color-success);
}

.symbol.amber {
  color: var(--color-warning);
}

.symbol.red {
  color: var(--color-danger);
}

/* -- Mobile FAB -- */
.mobile-fab {
  display: none;
  position: fixed;
  bottom: 2rem;
  right: 2rem;
  width: 3.5rem;
  height: 3.5rem;
  border-radius: 50%;
  background: var(--color-brand-primary);
  color: #ffffff;
  border: none;
  box-shadow: 0 4px 12px rgba(14, 165, 233, 0.4);
  z-index: 100;
  cursor: pointer;
  align-items: center;
  justify-content: center;
  font-size: 1.5rem;
  transition: var(--transition);
}

.mobile-fab:hover {
  transform: scale(1.1);
  box-shadow: 0 6px 16px rgba(14, 165, 233, 0.5);
}

@media (max-width: 900px) {
  .mobile-fab {
    display: flex;
  }
}

/* -- Specialized Gradients -- */
.severity-bar-bg.meld {
  background: linear-gradient(90deg,
      var(--color-success) 0%,
      var(--color-success) 20%,
      var(--color-warning) 30%,
      var(--color-danger) 100%);
}

.severity-bar-bg.bmi {
  background: linear-gradient(90deg,
      var(--color-danger) 0%,
      var(--color-warning) 15%,
      var(--color-success) 25%,
      var(--color-success) 40%,
      var(--color-warning) 50%,
      var(--color-danger) 100%);
}

.risk-indeterminate {
  border-left-color: var(--color-text-muted);
  background: var(--color-surface-card);
  /* Default glass */
}

/* -- Theme Toggle Icons -- */
[data-theme='light'] #theme-toggle span:nth-child(1) {
  display: none;
}

[data-theme='light'] #theme-toggle span:nth-child(2) {
  display: inline;
}

[data-theme='dark'] #theme-toggle span:nth-child(1) {
  display: inline;
}

[data-theme='dark'] #theme-toggle span:nth-child(2) {
  display: none;
}

/* -- Copy Button -- */
.btn-copy {
  padding: 0.75rem 1.5rem;
  background: rgba(14, 165, 233, 0.15);
  border: 1px solid var(--color-brand-primary);
  color: var(--color-brand-primary);
  border-radius: var(--radius-md);
  cursor: pointer;
  font-weight: 500;
  font-size: 0.9rem;
  transition: var(--transition);
  display: inline-flex;
  align-items: center;
  gap: 0.5rem;
}

.btn-copy:hover {
  background: rgba(14, 165, 233, 0.25);
  transform: translateY(-1px);
}


/* -- Validation & Warnings -- */
.field-wrapper.invalid input,
.field-wrapper.invalid select {
  border-color: var(--color-warning);
  background: rgba(234, 179, 8, 0.05);
  /* Yellow tint */
}

.warning-message {
  color: var(--color-warning);
  font-size: 0.8rem;
  margin-top: 0.4rem;
  display: flex;
  align-items: center;
  gap: 0.4rem;
  animation: fadeIn 0.3s ease-out;
}

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(-5px);
  }

  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* -- Footer Accordion (Details/Summary) -- */
.disclaimer {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  margin-bottom: 0.75rem;
  overflow: hidden;
}

.disclaimer>summary {
  padding: 0.75rem 1rem;
  cursor: pointer;
  font-weight: 600;
  color: var(--color-text-main);
  background: rgba(0, 0, 0, 0.1);
  list-style: none;
  display: flex;
  align-items: center;
  justify-content: space-between;
  transition: var(--transition);
}

.disclaimer>summary::after {
  content: '▼';
  font-size: 0.7rem;
  color: var(--color-text-muted);
  transition: transform 0.2s;
}

.disclaimer[open]>summary::after {
  transform: rotate(180deg);
}

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

.disclaimer>summary:hover {
  background: var(--color-surface-hover);
}

.disclaimer-content {
  padding: 1rem;
  font-size: 0.9rem;
  color: var(--color-text-muted);
}

.disclaimer-content p {
  margin: 0.5rem 0;
}

.disclaimer-content ul {
  margin: 0.5rem 0;
  padding-left: 1.5rem;
}

.disclaimer-content li {
  margin-bottom: 0.3rem;
}

.disclaimer-content small {
  display: block;
  margin-top: 0.5rem;
  font-size: 0.8rem;
  opacity: 0.8;
}

/* Nested Accordions - Level 1 */
.disclaimer.nested {
  margin-left: 0;
  border-left: 3px solid var(--color-brand-primary);
}

.disclaimer.nested>summary {
  font-size: 0.95rem;
}

/* Nested Accordions - Level 2 */
.disclaimer.nested-2 {
  margin-left: 0.5rem;
  border-left: 2px solid rgba(14, 165, 233, 0.5);
}

.disclaimer.nested-2>summary {
  font-size: 0.9rem;
  padding: 0.5rem 0.75rem;
}

/* Nested Accordions - Level 3 */
.disclaimer.nested-3 {
  margin-left: 0.5rem;
  border-left: 2px solid rgba(14, 165, 233, 0.3);
}

.disclaimer.nested-3>summary {
  font-size: 0.85rem;
  padding: 0.4rem 0.6rem;
}