/* ============================================================
   LUMINA CLARITY — Design System by Stitch
   "The Digital Concierge" — Accessible, Premium, Warm
   ============================================================ */

:root {
  /* ── Color Tokens (Lumina Clarity) ── */
  --color-primary: #005235;
  --color-primary-container: #1B6B4A;
  --color-primary-fixed: #A6F3C9;
  --color-primary-fixed-dim: #8AD6AE;

  --color-secondary: #875200;
  --color-secondary-container: #FFA528;
  --color-secondary-fixed: #FFDDBA;
  --color-secondary-fixed-dim: #FFB865;

  --color-tertiary: #753134;
  --color-tertiary-container: #92484A;

  --color-error: #BA1A1A;
  --color-error-container: #FFDAD6;

  --color-surface: #F9FAF4;
  --color-surface-dim: #D9DBD5;
  --color-surface-bright: #F9FAF4;
  --color-surface-container-lowest: #FFFFFF;
  --color-surface-container-low: #F3F4EE;
  --color-surface-container: #EDEEE8;
  --color-surface-container-high: #E7E9E3;
  --color-surface-container-highest: #E2E3DD;

  --color-on-surface: #1A1C19;
  --color-on-surface-variant: #3F4943;
  --color-on-primary: #FFFFFF;
  --color-on-secondary: #FFFFFF;
  --color-on-error: #FFFFFF;

  --color-outline: #6F7A72;
  --color-outline-variant: #BFC9C0;

  --color-inverse-surface: #2E312D;
  --color-inverse-on-surface: #F0F1EB;
  --color-inverse-primary: #8AD6AE;

  /* ── Spacing Scale (Generous for Accessibility) ── */
  --sp-1: 0.25rem;    /* 4px */
  --sp-2: 0.5rem;     /* 8px */
  --sp-3: 0.75rem;    /* 12px */
  --sp-4: 1rem;       /* 16px */
  --sp-5: 1.25rem;    /* 20px */
  --sp-6: 1.5rem;     /* 24px */
  --sp-8: 2rem;       /* 32px */
  --sp-10: 2.5rem;    /* 40px */
  --sp-12: 3rem;      /* 48px */
  --sp-16: 4rem;      /* 64px */

  /* ── Border Radius ── */
  --radius-sm: 0.5rem;     /* 8px */
  --radius-md: 0.75rem;    /* 12px */
  --radius-lg: 1rem;       /* 16px */
  --radius-xl: 1.5rem;     /* 24px */
  --radius-full: 9999px;

  /* ── Typography ── */
  --font-family: 'Inter', system-ui, -apple-system, sans-serif;

  /* Minimum 14px for labels, 16px for body — accessibility mandate */
  --font-label: 0.875rem;     /* 14px — absolute minimum */
  --font-body: 1rem;           /* 16px */
  --font-body-lg: 1.125rem;   /* 18px — preferred body */
  --font-title: 1.25rem;      /* 20px */
  --font-title-lg: 1.375rem;  /* 22px */
  --font-headline: 1.75rem;   /* 28px */
  --font-headline-lg: 2rem;   /* 32px */
  --font-display: 2.5rem;     /* 40px */
  --font-display-lg: 3rem;    /* 48px */

  /* ── Shadows (Ambient, not harsh) ── */
  --shadow-sm: 0 2px 8px rgba(26, 28, 25, 0.04);
  --shadow-md: 0 4px 16px rgba(26, 28, 25, 0.06);
  --shadow-lg: 0 8px 32px rgba(26, 28, 25, 0.06);
  --shadow-glow-primary: 0 4px 20px rgba(27, 107, 74, 0.15);

  /* ── Transitions ── */
  --trans-fast: 0.2s ease;
  --trans-normal: 0.35s ease;
  --trans-slow: 0.5s cubic-bezier(0.2, 0.8, 0.2, 1);
}

/* ============================================================
   RESET & BASE
   ============================================================ */

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  -webkit-tap-highlight-color: transparent;
}

body {
  background-color: var(--color-surface);
  color: var(--color-on-surface);
  font-family: var(--font-family);
  font-size: var(--font-body-lg);
  line-height: 1.6;
  min-height: 100vh;
  min-height: 100dvh;
  margin: 0;
  display: flex;
  justify-content: center;
  overflow-x: hidden;
  overscroll-behavior-y: none;
  -webkit-font-smoothing: antialiased;
  -moz-osx-font-smoothing: grayscale;
}

#app {
  width: 100%;
  max-width: 520px;
  min-height: 100vh;
  min-height: 100dvh;
  position: relative;
  display: flex;
  flex-direction: column;

  /* Signature "Energy Glow" texture */
  background:
    radial-gradient(ellipse at top right, rgba(0, 82, 53, 0.04) 0%, transparent 50%),
    radial-gradient(ellipse at bottom left, rgba(135, 82, 0, 0.03) 0%, transparent 50%),
    var(--color-surface);
}

/* ============================================================
   SCREEN SYSTEM
   ============================================================ */

.screen {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  opacity: 0;
  pointer-events: none;
  visibility: hidden;
  transition: opacity var(--trans-normal), transform var(--trans-normal);
  transform: translateY(12px);
  z-index: 10;
  overflow-y: auto;
  display: flex;
  flex-direction: column;
  background: var(--color-surface);
}

.screen.active {
  opacity: 1;
  pointer-events: auto;
  visibility: visible;
  transform: none;
  z-index: 20;
}

#screen-dashboard {
  background: var(--color-surface);
}

.screen-inner {
  padding: var(--sp-6) var(--sp-5);
  display: flex;
  flex-direction: column;
  min-height: 100%;
  max-width: 520px;
  margin: 0 auto;
  width: 100%;
}

.screen-inner.centered {
  justify-content: center;
}

/* ── Typography ── */
.screen-title {
  font-size: var(--font-headline);
  font-weight: 700;
  color: var(--color-on-surface);
  margin-bottom: var(--sp-3);
  line-height: 1.25;
  letter-spacing: -0.02em;
}

.screen-desc {
  color: var(--color-on-surface-variant);
  font-size: var(--font-body-lg);
  margin-bottom: var(--sp-8);
  line-height: 1.6;
}

.step-badge {
  display: inline-block;
  background: var(--color-primary-fixed);
  color: var(--color-primary);
  font-size: var(--font-label);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.08em;
  padding: 6px 14px;
  border-radius: var(--radius-full);
  margin-bottom: var(--sp-5);
}

/* ============================================================
   BUTTONS — Premium 3D Raised Style, 64px minimum
   ============================================================ */

.btn {
  background: transparent;
  border: none;
  color: var(--color-on-surface);
  font-family: var(--font-family);
  font-size: var(--font-body-lg);
  font-weight: 600;
  cursor: pointer;
  border-radius: 16px;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-3);
  user-select: none;
  min-height: 64px;
  padding: var(--sp-4) var(--sp-6);
  position: relative;
  overflow: hidden;
}

.btn:active {
  transform: scale(0.96) translateY(1px);
}

.btn:focus-visible {
  outline: 3px solid var(--color-primary-fixed);
  outline-offset: 3px;
}

/* ── Primary Button — Premium Raised Green ── */
.btn-primary {
  background: linear-gradient(180deg, #1E7E52 0%, #005235 100%);
  color: var(--color-on-primary);
  font-size: var(--font-title);
  font-weight: 700;
  letter-spacing: 0.01em;
  box-shadow:
    0 4px 0 0 #003D28,
    0 6px 16px rgba(0, 82, 53, 0.35),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  border-radius: 16px;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
}

.btn-primary:hover {
  background: linear-gradient(180deg, #22905E 0%, #006640 100%);
  box-shadow:
    0 5px 0 0 #003D28,
    0 8px 24px rgba(0, 82, 53, 0.4),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
  transform: translateY(-2px);
}

.btn-primary:active {
  box-shadow:
    0 1px 0 0 #003D28,
    0 2px 8px rgba(0, 82, 53, 0.3),
    inset 0 2px 4px rgba(0, 0, 0, 0.15);
  transform: translateY(2px) scale(0.98);
}

/* ── Secondary Button — Outlined with subtle fill ── */
.btn-secondary {
  background: var(--color-surface-container-lowest);
  color: var(--color-primary);
  font-weight: 700;
  border: 2px solid var(--color-primary-fixed-dim);
  box-shadow:
    0 2px 0 0 var(--color-surface-dim),
    0 3px 8px rgba(0, 0, 0, 0.06);
}

.btn-secondary:hover {
  background: var(--color-primary-fixed);
  border-color: var(--color-primary);
  box-shadow:
    0 3px 0 0 var(--color-surface-dim),
    0 4px 12px rgba(0, 82, 53, 0.12);
  transform: translateY(-1px);
}

.btn-secondary:active {
  box-shadow:
    0 0px 0 0 var(--color-surface-dim),
    inset 0 1px 3px rgba(0, 0, 0, 0.1);
  transform: translateY(1px) scale(0.98);
}

/* ── Danger Button ── */
.btn-danger {
  background: linear-gradient(180deg, #D32F2F 0%, #B71C1C 100%);
  color: var(--color-on-error);
  font-weight: 700;
  box-shadow:
    0 3px 0 0 #8E1414,
    0 4px 12px rgba(183, 28, 28, 0.3),
    inset 0 1px 0 rgba(255, 255, 255, 0.15);
}

.btn-danger:hover {
  background: linear-gradient(180deg, #E53935 0%, #C62828 100%);
  transform: translateY(-1px);
}

.btn-danger:active {
  box-shadow:
    0 1px 0 0 #8E1414,
    inset 0 2px 4px rgba(0, 0, 0, 0.2);
  transform: translateY(1px) scale(0.98);
}

/* ── Ghost Buttons — Clean text links ── */
.btn-ghost {
  padding: var(--sp-3) var(--sp-5);
  color: var(--color-on-surface-variant);
  font-size: var(--font-body);
  font-weight: 600;
  min-height: 52px;
  border-radius: 12px;
  background: transparent;
}

.btn-ghost:hover {
  color: var(--color-primary);
  background: rgba(166, 243, 201, 0.2);
}

.btn-ghost.danger {
  color: var(--color-outline);
}

.btn-ghost.danger:hover {
  color: var(--color-error);
  background: rgba(255, 218, 214, 0.4);
}

.btn-full {
  width: 100%;
}

/* ============================================================
   LANGUAGE SCREEN — Welcome
   ============================================================ */

#screen-language {
  background:
    radial-gradient(ellipse at top right, rgba(0, 82, 53, 0.06) 0%, transparent 50%),
    radial-gradient(ellipse at bottom left, rgba(135, 82, 0, 0.04) 0%, transparent 50%),
    var(--color-surface);
}

.logo-area {
  text-align: center;
  margin-bottom: var(--sp-12);
  position: relative;
}

.logo-glow {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -60%);
  width: 140px;
  height: 140px;
  background: var(--color-primary-fixed);
  filter: blur(60px);
  opacity: 0.5;
  z-index: -1;
  border-radius: 50%;
  animation: glowPulse 4s ease-in-out infinite;
}

@keyframes glowPulse {
  0%, 100% { opacity: 0.4; transform: translate(-50%, -60%) scale(1); }
  50% { opacity: 0.6; transform: translate(-50%, -60%) scale(1.1); }
}

.logo-icon {
  font-size: 4.5rem;
  margin-bottom: var(--sp-5);
  filter: drop-shadow(0 4px 12px rgba(27, 107, 74, 0.3));
  display: inline-block;
}

.app-title {
  font-size: var(--font-headline-lg);
  font-weight: 800;
  line-height: 1.15;
  margin-bottom: var(--sp-3);
  color: var(--color-primary);
  letter-spacing: -0.03em;
}

.app-subtitle {
  color: var(--color-on-surface-variant);
  font-size: var(--font-title);
  font-weight: 500;
}

.lang-choice {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  padding: var(--sp-6);
  margin-bottom: var(--sp-8);
  box-shadow: var(--shadow-md);
}

.choose-label {
  text-align: center;
  color: var(--color-on-surface-variant);
  margin-bottom: var(--sp-5);
  font-size: var(--font-body);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
}

.lang-buttons {
  display: flex;
  flex-direction: column;
  gap: var(--sp-4);
}

.btn-lang {
  background: var(--color-surface-container-low);
  padding: var(--sp-5);
  justify-content: flex-start;
  font-size: var(--font-title);
  font-weight: 600;
  min-height: 72px;
  border-radius: var(--radius-lg);
  transition: all var(--trans-fast);
}

.btn-lang:hover, .btn-lang:focus {
  background: var(--color-primary-fixed);
  transform: translateY(-2px);
  box-shadow: var(--shadow-md);
}

.lang-letter {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 44px;
  height: 44px;
  background: var(--color-surface-container-highest);
  border-radius: var(--radius-md);
  font-size: var(--font-title);
  margin-right: var(--sp-4);
  color: var(--color-primary);
  font-weight: 700;
  transition: all var(--trans-fast);
}

.btn-lang:hover .lang-letter {
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.disclaimer-small {
  text-align: center;
  font-size: var(--font-label);
  color: var(--color-outline);
  line-height: 1.5;
}

/* ============================================================
   ONBOARDING SCREEN
   ============================================================ */

.onboarding-top {
  margin-bottom: var(--sp-6);
}

.meter-illustration {
  background: var(--color-surface-container-low);
  border-radius: var(--radius-xl);
  padding: var(--sp-8) var(--sp-6);
  margin-bottom: var(--sp-6);
  display: flex;
  justify-content: center;
  box-shadow: var(--shadow-sm);
}

.meter-body {
  text-align: center;
  position: relative;
}

.meter-label {
  font-size: var(--font-label);
  color: var(--color-outline);
  margin-bottom: var(--sp-3);
  letter-spacing: 0.15em;
  font-weight: 600;
  text-transform: uppercase;
}

.meter-display {
  background: var(--color-surface-container-lowest);
  padding: var(--sp-3) var(--sp-5);
  border-radius: var(--radius-md);
  display: inline-flex;
  align-items: center;
  box-shadow: var(--shadow-sm);
  font-family: 'Courier New', Courier, monospace;
  font-size: var(--font-display);
  font-weight: 900;
}

.meter-digits-group {
  display: flex;
}

.meter-digits-group.highlighted {
  border: 3px solid var(--color-primary);
  border-radius: var(--radius-sm);
  padding: 4px;
  background: rgba(166, 243, 201, 0.2);
}

.meter-digits-group.dimmed {
  opacity: 0.35;
}

.meter-digit {
  width: 32px;
  text-align: center;
  color: var(--color-on-surface);
  background: var(--color-surface-container-lowest);
  margin: 0 2px;
  border-radius: 4px;
}

.meter-digit.red {
  color: var(--color-error);
}

.meter-dot {
  color: var(--color-on-surface);
  margin: 0 4px;
  font-weight: 900;
}

.meter-pointer {
  position: absolute;
  top: 100%;
  left: 30%;
  transform: translateX(-50%);
  display: flex;
  flex-direction: column;
  align-items: center;
  color: var(--color-primary);
  margin-top: var(--sp-3);
}

.pointer-arrow {
  font-size: var(--font-title-lg);
  line-height: 1;
  animation: gentleBounce 2.5s ease-in-out infinite;
}

.pointer-label {
  font-size: var(--font-label);
  font-weight: 700;
  background: var(--color-primary-fixed);
  color: var(--color-primary);
  padding: 6px 12px;
  border-radius: var(--radius-full);
  white-space: nowrap;
  margin-top: var(--sp-2);
}

@keyframes gentleBounce {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-8px); }
}

.info-card {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-lg);
  padding: var(--sp-5);
  margin-bottom: auto;
  box-shadow: var(--shadow-sm);
}

.example-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: var(--sp-3);
  padding-bottom: var(--sp-3);
}

.example-label {
  color: var(--color-on-surface-variant);
  font-size: var(--font-body);
  font-weight: 600;
}

.example-values {
  font-family: monospace;
  font-size: var(--font-title-lg);
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

.example-before {
  color: var(--color-outline);
  text-decoration: line-through;
}

.example-arrow {
  color: var(--color-primary);
  font-weight: 700;
}

.example-after {
  color: var(--color-primary);
  font-weight: 800;
}

.info-note {
  font-size: var(--font-body);
  color: var(--color-on-surface-variant);
  display: flex;
  align-items: flex-start;
  gap: var(--sp-3);
  line-height: 1.5;
}

.info-note::before {
  content: "💡";
  flex-shrink: 0;
  font-size: 1.2rem;
}

/* ============================================================
   SETUP SCREEN
   ============================================================ */

.setup-top {
  margin-bottom: var(--sp-6);
}

.setup-icon-wrap {
  width: 80px;
  height: 80px;
  background: var(--color-primary-fixed);
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin-bottom: var(--sp-5);
  font-size: 2.5rem;
  box-shadow: var(--shadow-sm);
}

.input-group {
  position: relative;
  margin-bottom: var(--sp-5);
}

.input-reading {
  width: 100%;
  background: var(--color-surface-container-high);
  border: none;
  border-bottom: 3px solid var(--color-outline-variant);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  padding: var(--sp-10) var(--sp-5) var(--sp-4);
  color: var(--color-on-surface);
  font-family: inherit;
  font-size: var(--font-display);
  font-weight: 700;
  text-align: center;
  transition: all var(--trans-fast);
  outline: none;
  letter-spacing: -0.02em;
}

.input-reading:focus {
  border-bottom-color: var(--color-primary);
  background: var(--color-surface-container);
}

.input-reading::placeholder {
  color: var(--color-outline-variant);
}

.input-label {
  position: absolute;
  top: var(--sp-4);
  left: 50%;
  transform: translateX(-50%);
  font-size: var(--font-label);
  color: var(--color-on-surface-variant);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  font-weight: 700;
  pointer-events: none;
  white-space: nowrap;
}

.input-hint {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  font-size: var(--font-body);
  color: var(--color-on-surface-variant);
  background: var(--color-surface-container-low);
  padding: var(--sp-4);
  border-radius: var(--radius-lg);
  margin-top: var(--sp-5);
  margin-bottom: var(--sp-6);
  line-height: 1.5;
}

/* ============================================================
   DASHBOARD
   ============================================================ */

.dash-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--sp-4) var(--sp-5);
  background: rgba(249, 250, 244, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  position: sticky;
  top: 0;
  z-index: 30;
}

.dash-header-left {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
}

.dash-logo {
  font-size: 1.75rem;
  filter: drop-shadow(0 2px 6px rgba(27, 107, 74, 0.25));
}

.dash-title {
  font-weight: 800;
  font-size: var(--font-title);
  color: var(--color-primary);
  letter-spacing: -0.02em;
}

.btn-install {
  background: transparent;
  border: 2px solid var(--color-primary-fixed);
  color: var(--color-primary);
  padding: 8px;
  border-radius: var(--radius-full);
  cursor: pointer;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: all var(--trans-fast);
  min-height: 40px;
  min-width: 40px;
}

.btn-install:hover {
  background: var(--color-primary-fixed);
}

.btn-lang-toggle {
  background: var(--color-primary-fixed);
  border: none;
  color: var(--color-primary);
  padding: 8px 18px;
  border-radius: var(--radius-full);
  font-size: var(--font-label);
  font-weight: 800;
  cursor: pointer;
  letter-spacing: 0.05em;
  transition: all var(--trans-fast);
  min-height: 40px;
}

.btn-lang-toggle:hover {
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.dash-body {
  padding: var(--sp-5) var(--sp-5) var(--sp-16);
  display: flex;
  flex-direction: column;
  gap: var(--sp-5);
}

/* ── Input Section ── */
.dash-input-section {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  padding: var(--sp-8) var(--sp-6);
  box-shadow: var(--shadow-lg);
  position: relative;
  overflow: hidden;
}

.dash-input-section::before {
  content: '';
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
  background: linear-gradient(90deg, var(--color-primary), var(--color-primary-fixed-dim), var(--color-primary));
  border-radius: var(--radius-xl) var(--radius-xl) 0 0;
}

.input-main-label {
  display: block;
  text-align: center;
  color: var(--color-on-surface-variant);
  font-weight: 700;
  font-size: var(--font-body);
  text-transform: uppercase;
  letter-spacing: 0.08em;
  margin-bottom: var(--sp-5);
}

.input-wrapper {
  position: relative;
  margin-bottom: var(--sp-5);
}

.input-reading.large {
  font-size: var(--font-display-lg);
  padding: var(--sp-5) var(--sp-4);
  background: var(--color-surface-container-high);
  border: none;
  border-bottom: 3px solid var(--color-outline-variant);
  border-radius: var(--radius-lg) var(--radius-lg) 0 0;
  letter-spacing: -0.02em;
}

.input-reading.large:focus {
  border-bottom-color: var(--color-primary);
  background: var(--color-surface-container);
}

.input-feedback {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-3);
  font-size: var(--font-body);
  font-weight: 600;
  margin-bottom: var(--sp-5);
  padding: var(--sp-3);
  border-radius: var(--radius-md);
  opacity: 0;
  height: 0;
  overflow: hidden;
  transition: all var(--trans-fast);
  color: var(--color-primary);
}

.input-feedback.show {
  opacity: 1;
  height: auto;
  background: rgba(166, 243, 201, 0.15);
}

.input-feedback .feedback-icon {
  color: var(--color-primary);
}

.input-feedback.error {
  background: var(--color-error-container);
  color: var(--color-error);
}

.input-feedback.error.show {
  background: var(--color-error-container);
}

.input-feedback.error .feedback-icon {
  color: var(--color-error);
}

/* ── Calculate Button — The Hero CTA ── */
.btn-calculate {
  background: linear-gradient(180deg, #1E7E52 0%, #005235 100%);
  color: var(--color-on-primary);
  width: 100%;
  min-height: 68px;
  padding: var(--sp-5) var(--sp-6);
  font-size: var(--font-title-lg);
  font-weight: 800;
  border-radius: 16px;
  letter-spacing: 0.02em;
  text-shadow: 0 1px 2px rgba(0, 0, 0, 0.2);
  box-shadow:
    0 5px 0 0 #003D28,
    0 8px 20px rgba(0, 82, 53, 0.35),
    inset 0 1px 0 rgba(255, 255, 255, 0.2);
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
}

.btn-calculate:hover {
  background: linear-gradient(180deg, #22905E 0%, #006640 100%);
  box-shadow:
    0 6px 0 0 #003D28,
    0 10px 28px rgba(0, 82, 53, 0.4),
    inset 0 1px 0 rgba(255, 255, 255, 0.25);
  transform: translateY(-2px);
}

.btn-calculate:active {
  box-shadow:
    0 1px 0 0 #003D28,
    0 2px 6px rgba(0, 82, 53, 0.25),
    inset 0 2px 4px rgba(0, 0, 0, 0.15);
  transform: translateY(3px) scale(0.98);
}

.btn-arrow {
  transition: transform 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  font-size: 1.4rem;
  opacity: 0.9;
}

.btn-calculate:hover .btn-arrow {
  transform: translateX(6px);
  opacity: 1;
}

/* ============================================================
   RESULT CARDS
   ============================================================ */

.results-container {
  display: flex;
  flex-direction: column;
  gap: var(--sp-5);
  display: none;
}

.card {
  background: var(--color-surface-container-lowest);
  border-radius: var(--radius-xl);
  padding: var(--sp-6);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-md);
}

.card-header {
  display: flex;
  align-items: center;
  gap: var(--sp-3);
  margin-bottom: var(--sp-3);
}

.card-emoji {
  font-size: 1.5rem;
}

.card-title {
  color: var(--color-on-surface-variant);
  font-size: var(--font-body);
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.06em;
}

.big-number {
  font-size: var(--font-display-lg);
  font-weight: 800;
  line-height: 1;
  color: var(--color-on-surface);
  letter-spacing: -0.03em;
}

.big-number-unit {
  font-size: var(--font-title);
  color: var(--color-on-surface-variant);
  font-weight: 600;
  margin-left: 6px;
}

.card-sub {
  display: block;
  font-size: var(--font-label);
  color: var(--color-outline);
  margin-top: var(--sp-2);
  font-weight: 500;
}

/* ── Specific Card Styles — Colored Left Accents ── */
.card-units {
  background: var(--color-surface-container-lowest);
  border-left: 5px solid var(--color-primary);
}

.card-bill {
  background: var(--color-surface-container-lowest);
  border-left: 5px solid var(--color-primary-fixed-dim);
}

.bill-amount {
  color: var(--color-primary);
}

/* ── Per-unit price display ── */
.unit-price-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-top: var(--sp-4);
  padding: var(--sp-3) var(--sp-4);
  background: var(--color-primary-fixed);
  border-radius: 10px;
}

.unit-price-label {
  font-size: var(--font-body);
  color: var(--color-on-surface-variant);
  font-weight: 500;
}

.unit-price-value {
  font-size: var(--font-title);
  color: var(--color-primary);
  font-weight: 800;
}

/* ── Receipt Button (View Breakdown) ── */
.btn-receipt {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: var(--sp-3);
  width: 100%;
  margin-top: var(--sp-5);
  padding: var(--sp-4);
  background: var(--color-surface-container-low);
  border: 2px dashed var(--color-outline-variant);
  border-radius: 12px;
  cursor: pointer;
  font-family: inherit;
  font-size: var(--font-body);
  font-weight: 700;
  color: var(--color-primary);
  transition: all 0.2s ease;
}

.btn-receipt:hover {
  background: var(--color-primary-fixed);
  border-color: var(--color-primary);
}

.btn-receipt .receipt-icon {
  font-size: 1.3rem;
}

.btn-receipt .expand-arrow {
  font-size: 1.4rem;
  font-weight: 700;
  transition: transform 0.25s ease;
  margin-left: auto;
}

.btn-receipt.open .expand-arrow {
  transform: rotate(90deg);
}

/* ── Receipt Breakdown Panel ── */
.breakdown-panel {
  display: none;
  background: var(--color-surface-container-lowest);
  border-radius: 16px;
  padding: 0;
  overflow: hidden;
  box-shadow: var(--shadow-md);
  border: 1px solid var(--color-surface-container-high);
}

.receipt-header {
  background: var(--color-surface-container-low);
  padding: var(--sp-4) var(--sp-5);
  border-bottom: 2px dashed var(--color-outline-variant);
}

.receipt-title {
  font-size: var(--font-body);
  font-weight: 700;
  color: var(--color-on-surface);
  text-transform: uppercase;
  letter-spacing: 0.08em;
}

/* Receipt Sections */
.receipt-section {
  padding: var(--sp-4) var(--sp-5);
  border-bottom: 1px solid var(--color-surface-container-high);
}

.receipt-section:last-of-type {
  border-bottom: none;
}

.receipt-section-title {
  font-size: var(--font-label);
  font-weight: 700;
  color: var(--color-outline);
  text-transform: uppercase;
  letter-spacing: 0.06em;
  margin-bottom: var(--sp-3);
}

/* Receipt Line Items */
.receipt-item {
  display: flex;
  align-items: baseline;
  padding: var(--sp-2) 0;
  gap: var(--sp-2);
}

.receipt-item-left {
  display: flex;
  flex-direction: column;
  flex-shrink: 0;
}

.receipt-item-name {
  font-size: var(--font-body);
  font-weight: 600;
  color: var(--color-on-surface);
}

.receipt-item-detail {
  font-size: var(--font-label);
  color: var(--color-outline);
  font-weight: 500;
}

.receipt-item-dots {
  flex: 1;
  border-bottom: 2px dotted var(--color-outline-variant);
  margin: 0 var(--sp-2);
  min-width: 20px;
  align-self: center;
  margin-bottom: 4px;
}

.receipt-item-price {
  font-size: var(--font-body);
  font-weight: 600;
  color: var(--color-on-surface);
  flex-shrink: 0;
  white-space: nowrap;
}

/* Receipt Subtotal */
.receipt-subtotal {
  display: flex;
  justify-content: space-between;
  margin-top: var(--sp-3);
  padding-top: var(--sp-3);
  border-top: 1px dashed var(--color-outline-variant);
  font-size: var(--font-body);
  font-weight: 600;
  color: var(--color-on-surface-variant);
}

/* Receipt Grand Total */
.receipt-total {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--sp-5);
  background: var(--color-primary);
  color: var(--color-on-primary);
}

.receipt-total-label {
  font-size: var(--font-title);
  font-weight: 700;
}

.receipt-total-amount {
  font-size: var(--font-headline);
  font-weight: 800;
  letter-spacing: -0.02em;
}

/* Per-unit callout */
.receipt-per-unit {
  padding: var(--sp-4) var(--sp-5);
  background: var(--color-primary-fixed);
  font-size: var(--font-body);
  font-weight: 600;
  color: var(--color-primary);
  text-align: center;
  border-radius: 0 0 16px 16px;
}

.breakdown-note {
  font-size: var(--font-label);
  color: var(--color-outline);
  padding: var(--sp-3) var(--sp-5) var(--sp-4);
  line-height: 1.5;
  text-align: center;
}

/* ── Slab Bar ── */
.card-slab {
  border-left: 5px solid #5B8DEF;
}

.slab-bar-wrap {
  margin-top: var(--sp-4);
}

.slab-bar {
  height: 14px;
  background: var(--color-surface-container-high);
  border-radius: var(--radius-full);
  overflow: hidden;
  margin-bottom: var(--sp-3);
  box-shadow: inset 0 1px 3px rgba(0, 0, 0, 0.08);
}

.slab-bar-fill {
  height: 100%;
  background: linear-gradient(90deg, #A6F3C9, var(--color-primary));
  width: 0%;
  border-radius: var(--radius-full);
  transition: width 1.2s cubic-bezier(0.2, 0.8, 0.2, 1), background-color var(--trans-normal);
  box-shadow: 0 1px 3px rgba(0, 82, 53, 0.3);
}

.slab-bar-fill.warning {
  background: linear-gradient(90deg, #FFE0A0, #E8920D);
  box-shadow: 0 1px 3px rgba(135, 82, 0, 0.3);
}

.slab-bar-fill.danger {
  background: linear-gradient(90deg, #FFDAD6, var(--color-error));
  box-shadow: 0 1px 3px rgba(186, 26, 26, 0.3);
}

.slab-bar-text {
  font-size: var(--font-body);
  font-weight: 600;
  color: var(--color-on-surface-variant);
  display: flex;
  justify-content: space-between;
}

/* ── Warning Card ── */
.card-warning {
  display: none;
  background: #FFF8E8;
  border-left: 5px solid #E8920D;
}

.warning-pulse {
  display: none;
}

.warning-text {
  font-weight: 700;
  color: var(--color-secondary);
  margin-bottom: var(--sp-2);
  font-size: var(--font-body-lg);
  line-height: 1.5;
}

.warning-action {
  font-size: var(--font-body);
  color: var(--color-on-surface-variant);
  line-height: 1.5;
}

.card-warning .card-title {
  color: var(--color-secondary);
}

/* ── Insight + Prediction — Simplified Advice Strip ── */
.card-insight {
  background: var(--color-surface-container-lowest);
  border-left: 5px solid #E8920D;
}

.insight-text {
  font-size: var(--font-body-lg);
  font-weight: 500;
  color: var(--color-on-surface);
  line-height: 1.7;
}

.card-prediction {
  background: var(--color-surface-container-low);
  border-left: 5px solid var(--color-primary-fixed-dim);
  box-shadow: none;
}

.prediction-text {
  font-size: var(--font-body-lg);
  color: var(--color-on-surface);
  line-height: 1.7;
}

/* ── History ── */
.card-history {
  border-left: 5px solid var(--color-outline-variant);
}

.history-list {
  display: flex;
  flex-direction: column;
  gap: var(--sp-3);
  margin-top: var(--sp-3);
}

.history-empty {
  font-size: var(--font-body);
  color: var(--color-outline);
  text-align: center;
  padding: var(--sp-5) 0;
}

.history-item {
  display: flex;
  justify-content: space-between;
  align-items: center;
  background: var(--color-surface-container-low);
  padding: var(--sp-4) var(--sp-5);
  border-radius: 12px;
  font-size: var(--font-body);
  transition: background var(--trans-fast);
}

.history-item:hover {
  background: var(--color-surface-container);
}

.hist-date {
  color: var(--color-on-surface-variant);
  font-weight: 500;
}

.hist-units {
  font-weight: 700;
  color: var(--color-on-surface);
  font-size: var(--font-body-lg);
}

.hist-trend {
  font-size: 1.4rem;
}

.trend-up { color: var(--color-error); }
.trend-down { color: var(--color-primary); }
.trend-flat { color: var(--color-outline); }

/* ============================================================
   ANIMATIONS — Gentle, Not Jarring
   ============================================================ */

.animate-card {
  opacity: 0;
  transform: translateY(16px);
}

.animate-card.show {
  animation: fadeSlideUp 0.5s cubic-bezier(0.2, 0.8, 0.2, 1) forwards;
  animation-delay: calc(var(--delay) * 0.12s);
}

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

/* ============================================================
   SETTINGS & FOOTER
   ============================================================ */

.settings-row {
  display: flex;
  justify-content: center;
  gap: var(--sp-6);
  margin-top: var(--sp-5);
  padding-top: var(--sp-5);
}

.dash-footer {
  text-align: center;
  margin-top: var(--sp-10);
  padding-bottom: var(--sp-8);
}

.footer-disclaimer,
.footer-update {
  font-size: var(--font-label);
  color: var(--color-outline);
  margin-bottom: 4px;
  line-height: 1.5;
}

/* ============================================================
   MODALS
   ============================================================ */

.modal-overlay {
  position: fixed;
  top: 0;
  left: 0;
  width: 100%;
  height: 100%;
  background: rgba(26, 28, 25, 0.6);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: var(--sp-5);
  opacity: 0;
  pointer-events: none;
  transition: opacity var(--trans-normal);
}

.modal-overlay.show {
  opacity: 1;
  pointer-events: auto;
}

.modal-card {
  background: var(--color-surface-container-lowest);
  width: 100%;
  max-width: 420px;
  border-radius: var(--radius-xl);
  padding: var(--sp-8);
  box-shadow: var(--shadow-lg);
  transform: translateY(24px) scale(0.95);
  transition: transform var(--trans-slow);
}

.modal-overlay.show .modal-card {
  transform: translateY(0) scale(1);
}

.modal-card h3 {
  margin-bottom: var(--sp-3);
  font-size: var(--font-headline);
  font-weight: 700;
  color: var(--color-on-surface);
  letter-spacing: -0.02em;
}

.modal-card p {
  color: var(--color-on-surface-variant);
  font-size: var(--font-body);
  margin-bottom: var(--sp-6);
  line-height: 1.6;
}

.input-group.compact .input-reading {
  padding: var(--sp-8) var(--sp-4) var(--sp-3);
  font-size: var(--font-headline);
}

.modal-actions {
  display: flex;
  justify-content: flex-end;
  gap: var(--sp-3);
  margin-top: var(--sp-6);
}

.modal-actions .btn {
  padding: var(--sp-3) var(--sp-6);
  min-height: 52px;
  border-radius: var(--radius-lg);
}

/* ============================================================
   TAB SYSTEM & BOTTOM NAVIGATION
   ============================================================ */

.tab-content {
  overflow-y: auto;
  padding-bottom: 68px; /* Space for bottom nav */
  min-height: calc(100vh - 64px);
  min-height: calc(100dvh - 64px);
}

.bottom-nav {
  position: fixed;
  bottom: 0;
  left: 0;
  right: 0;
  display: flex;
  justify-content: space-around;
  align-items: stretch;
  background: var(--color-surface-container-lowest);
  border-top: 1px solid var(--color-outline-variant);
  padding: 0;
  margin: 0;
  z-index: 50;
  box-shadow: 0 -2px 12px rgba(0, 0, 0, 0.08);
}

.bottom-nav::after {
  content: '';
  position: absolute;
  top: 99%;
  left: 0;
  right: 0;
  height: 50vh;
  background: inherit;
  z-index: -1;
}

.nav-item {
  flex: 1;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 3px;
  padding: 8px 4px;
  padding-bottom: max(8px, env(safe-area-inset-bottom, 8px));
  min-height: 56px;
  border: none;
  background: transparent;
  cursor: pointer;
  font-family: inherit;
  transition: all 0.2s ease;
  position: relative;
  border-radius: 0;
  -webkit-tap-highlight-color: transparent;
}

.nav-icon {
  width: 24px;
  height: 24px;
  display: flex;
  align-items: center;
  justify-content: center;
  transition: transform 0.2s ease;
}

.nav-icon svg,
.svg-icon {
  width: 1.2em;
  height: 1.2em;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
  display: inline-block;
  vertical-align: middle;
}

.nav-icon svg {
  width: 22px;
  height: 22px;
  stroke: var(--color-outline);
  transition: stroke 0.2s ease;
}

.nav-item.active .nav-icon svg {
  stroke: var(--color-primary);
  stroke-width: 2.5;
}

.nav-label {
  font-size: 0.68rem;
  font-weight: 600;
  color: var(--color-outline);
  letter-spacing: 0.02em;
  transition: color 0.2s ease;
}

.nav-item.active .nav-label {
  color: var(--color-primary);
  font-weight: 800;
}

.nav-item.active .nav-icon {
  transform: scale(1.1);
}

.nav-item.active::before {
  content: '';
  position: absolute;
  top: 0;
  left: 20%;
  right: 20%;
  height: 3px;
  background: var(--color-primary);
  border-radius: 0 0 6px 6px;
}

.nav-item:active {
  background: rgba(0, 82, 53, 0.05);
}

/* ============================================================
   MICRO-INTERACTIONS — Make It Feel Alive
   ============================================================ */

/* Cards lift slightly on hover */
.card {
  transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
  transform: translateY(-2px);
  box-shadow: 0 6px 20px rgba(26, 28, 25, 0.08);
}

/* Input focus glow */
.input-reading:focus {
  box-shadow: 0 0 0 3px rgba(27, 107, 74, 0.15);
}

/* Big number subtle count-up shimmer */
.big-number {
  transition: color 0.3s ease;
}

/* Smooth tab transitions */
.tab-content {
  animation: tabFadeIn 0.3s ease;
}

@keyframes tabFadeIn {
  from { opacity: 0.7; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}

/* History item tap feedback */
.history-item:active {
  transform: scale(0.98);
  transition: transform 0.1s ease;
}

/* Rate row hover */
.rate-row {
  transition: background 0.2s ease, transform 0.15s ease;
}

.rate-row:hover {
  transform: translateX(4px);
}

/* Receipt button pulse hint on first appearance */
.btn-receipt {
  animation: subtlePulse 3s ease-in-out 1s 2;
}

@keyframes subtlePulse {
  0%, 100% { border-color: var(--color-outline-variant); }
  50% { border-color: var(--color-primary); background: rgba(166, 243, 201, 0.1); }
}

/* ============================================================
   KSEB RATE TABLE
   ============================================================ */

.card-rate-info {
  border-left: 5px solid var(--color-primary-fixed-dim);
}

.rate-table {
  display: flex;
  flex-direction: column;
  gap: 2px;
  margin-top: var(--sp-3);
}

.rate-row {
  display: flex;
  justify-content: space-between;
  align-items: center;
  padding: var(--sp-3) var(--sp-4);
  background: var(--color-surface-container-low);
  border-radius: 8px;
  font-size: var(--font-body);
}

.rate-row.highlight {
  background: rgba(166, 243, 201, 0.15);
}

.rate-row.highlight.warn {
  background: rgba(255, 184, 101, 0.15);
}

.rate-row.highlight.danger {
  background: rgba(255, 218, 214, 0.3);
}

.rate-range {
  color: var(--color-on-surface-variant);
  font-weight: 500;
}

.rate-price {
  color: var(--color-on-surface);
  font-weight: 700;
  font-size: var(--font-body-lg);
}

.rate-unit {
  font-size: var(--font-label);
  font-weight: 500;
  color: var(--color-outline);
}

.rate-note {
  font-size: var(--font-label);
  color: var(--color-outline);
  margin-top: var(--sp-4);
  line-height: 1.5;
  text-align: center;
}

/* ============================================================
   TUTORIAL
   ============================================================ */

.tutorial-content {
  padding-top: var(--sp-3);
}

.tutorial-step {
  display: flex;
  align-items: flex-start;
  gap: var(--sp-4);
  margin-bottom: var(--sp-5);
}

.tutorial-num {
  display: flex;
  align-items: center;
  justify-content: center;
  width: 36px;
  height: 36px;
  min-width: 36px;
  background: var(--color-primary);
  color: var(--color-on-primary);
  font-weight: 800;
  font-size: var(--font-body-lg);
  border-radius: 50%;
  flex-shrink: 0;
}

.tutorial-step p {
  font-size: var(--font-body-lg);
  color: var(--color-on-surface);
  line-height: 1.6;
  padding-top: 5px;
}

.tutorial-info {
  font-size: var(--font-body);
  color: var(--color-on-surface-variant);
  line-height: 1.7;
  margin-bottom: var(--sp-4);
}

.tutorial-info:last-child {
  margin-bottom: 0;
}

/* ============================================================
   EMPTY STATE
   ============================================================ */

.empty-state {
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  padding: var(--sp-16) var(--sp-6);
  text-align: center;
}

.empty-icon {
  font-size: 4rem;
  margin-bottom: var(--sp-5);
  opacity: 0.6;
}

.empty-title {
  font-size: var(--font-title-lg);
  font-weight: 700;
  color: var(--color-on-surface);
  margin-bottom: var(--sp-3);
}

.empty-desc {
  font-size: var(--font-body);
  color: var(--color-outline);
  margin-bottom: var(--sp-8);
  line-height: 1.5;
}

/* ============================================================
   RESPONSIVE — Larger screens
   ============================================================ */

@media (min-width: 480px) {
  .screen-inner {
    padding: var(--sp-8) var(--sp-6);
  }

  .dash-body {
    padding: var(--sp-6) var(--sp-6) var(--sp-16);
  }

  .bottom-nav {
    max-width: 520px;
    left: 50%;
    transform: translateX(-50%);
    border-radius: 20px 20px 0 0;
  }
}

/* ============================================================
   ACCESSIBILITY OVERRIDES
   ============================================================ */

/* Respect reduced motion preferences */
@media (prefers-reduced-motion: reduce) {
  *,
  *::before,
  *::after {
    animation-duration: 0.01ms !important;
    animation-iteration-count: 1 !important;
    transition-duration: 0.01ms !important;
  }
}

/* High contrast mode support */
@media (prefers-contrast: high) {
  .card {
    border: 2px solid var(--color-outline);
  }

  .btn-primary,
  .btn-calculate {
    border: 2px solid var(--color-on-primary);
  }

  .input-reading {
    border: 2px solid var(--color-on-surface);
  }

  .bottom-nav {
    border-top: 2px solid var(--color-outline);
  }
}

/* Focus styles for keyboard navigation */
*:focus-visible {
  outline: 3px solid var(--color-primary);
  outline-offset: 2px;
}