/* ============================================================
   BTECH Assessment Platform — Shared Design Tokens v6.0
   Fully Responsive & Mobile-First Architecture
   ============================================================ */

@import url('https://fonts.googleapis.com/css2?family=IBM+Plex+Sans+Arabic:wght@300;400;500;600;700&family=Montserrat:wght@300;400;500;600;700&family=Orbitron:wght@400;600;700;900&family=Inter:wght@300;400;500;600&family=Noto+Sans+Arabic:wght@300;400;500;600;700&display=swap');

/* ── 1. CSS Variables ── */
:root {
  --bg: #070913;
  --text: #e2e8f0;
  --sub-text: #94a3b8;
  --accent: #00ffff;
  --accent-alt: #8b5cf6;
  --glass-bg: rgba(255, 255, 255, 0.035);
  --glass-border: rgba(0, 255, 255, 0.12);
  --input-bg: rgba(0, 255, 255, 0.03);
  --opt-bg: rgba(255, 255, 255, 0.025);
  --opt-border: rgba(255, 255, 255, 0.07);
  --opt-hover: rgba(0, 255, 255, 0.06);
  --card-shadow: 0 30px 60px rgba(0, 0, 0, 0.6);
  --sidebar-bg: rgba(255, 255, 255, 0.02);
  --sidebar-border: rgba(139, 92, 246, 0.1);
  --card-bg: rgba(255, 255, 255, 0.025);
  --input-border: rgba(139, 92, 246, 0.18);
  --table-hover: rgba(139, 92, 246, 0.04);
  --trans: all 0.3s cubic-bezier(0.4, 0, 0.2, 1);
  
  /* Touch & Spacing Tokens */
  --touch-target: 48px;
  --safe-padding: 1.5rem;
}

body.light-mode {
  --bg: #f8fafc;
  --text: #0f172a;
  --sub-text: #475569;
  --accent: #0891b2;
  --accent-alt: #7c3aed;
  --glass-bg: rgba(255, 255, 255, 0.85);
  --glass-border: rgba(8, 145, 178, 0.2);
  --input-bg: #f1f5f9;
  --opt-bg: #ffffff;
  --opt-border: rgba(0, 0, 0, 0.05);
  --opt-hover: rgba(8, 145, 178, 0.05);
  --card-shadow: 0 20px 50px rgba(0, 0, 0, 0.05);
  --sidebar-bg: #ffffff;
  --sidebar-border: rgba(109, 40, 217, 0.08);
  --card-bg: #ffffff;
  --input-border: #e2e8f0;
  --table-hover: #f1f5f9;
}

/* ── 2. Base & Resets ── */
*, *::before, *::after {
  margin: 0; padding: 0; box-sizing: border-box;
  -webkit-tap-highlight-color: transparent;
}

html {
  scroll-behavior: smooth;
  font-size: 16px;
}

body {
  background: var(--bg);
  color: var(--text);
  font-family: 'Inter', sans-serif;
  min-height: 100vh;
  overflow-x: hidden;
  transition: background 0.5s ease, color 0.5s ease;
  line-height: 1.5;
  -webkit-text-size-adjust: 100%;
}

body.rtl { direction: rtl; font-family: 'IBM Plex Sans Arabic', sans-serif; }
body.ltr { direction: ltr; font-family: 'Montserrat', sans-serif; }

/* Scrollbar */
::-webkit-scrollbar { width: 4px; height: 4px; }
::-webkit-scrollbar-track { background: transparent; }
::-webkit-scrollbar-thumb { background: rgba(139,92,246,.3); border-radius: 2px; }

/* ── 3. Layout & Containers ── */
.layout { display: flex; min-height: 100vh; position: relative; }

.glass {
  background: var(--glass-bg);
  backdrop-filter: blur(24px); -webkit-backdrop-filter: blur(24px);
  border: 1px solid var(--glass-border);
  border-radius: 24px;
  padding: var(--safe-padding);
  width: 100%;
  box-shadow: var(--card-shadow);
  transition: var(--trans);
  animation: fadeIn 0.5s ease both;
}

.grid2, .grid3, .grid4 {
  display: grid;
  gap: 1.5rem;
}

.grid2 { grid-template-columns: repeat(2, 1fr); }
.grid3 { grid-template-columns: repeat(3, 1fr); }
.grid4 { grid-template-columns: repeat(4, 1fr); }

/* ── 4. Components ── */
.btn {
  min-height: var(--touch-target);
  padding: 0.75rem 1.5rem;
  border: none;
  border-radius: 12px;
  font-family: 'Orbitron', monospace;
  font-size: 0.8rem;
  font-weight: 700;
  letter-spacing: 2px;
  cursor: pointer;
  transition: var(--trans);
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 0.5rem;
  text-decoration: none;
}

.btn:active { transform: scale(0.96); }
.btn:disabled { opacity: 0.5; cursor: not-allowed; }

.btn-c { background: linear-gradient(135deg, rgba(0,255,255,.12), rgba(0,180,255,.08)); border: 1px solid rgba(0,255,255,.3); color: var(--accent); }
.btn-p { background: linear-gradient(135deg, rgba(139,92,246,.18), rgba(167,139,250,.12)); border: 1px solid rgba(139,92,246,.35); color: var(--accent-alt); }
.btn-g { background: linear-gradient(135deg, rgba(34,197,94,.15), rgba(16,185,129,.1)); border: 1px solid rgba(34,197,94,.3); color: #4ade80; }
.btn-r { background: rgba(239,68,68,.1); border: 1px solid rgba(239,68,68,.3); color: #fca5a5; }

/* Form Elements */
.field { margin-bottom: 1.5rem; }
label {
  display: block;
  font-size: 0.65rem;
  font-weight: 700;
  color: var(--accent);
  letter-spacing: 2px;
  text-transform: uppercase;
  margin-bottom: 0.5rem;
  opacity: 0.9;
}

input, select, textarea {
  width: 100%;
  min-height: var(--touch-target);
  padding: 0.75rem 1.25rem;
  background: var(--input-bg);
  border: 1px solid var(--input-border);
  border-radius: 12px;
  color: var(--text);
  font-family: 'Inter', sans-serif;
  font-size: 1rem; /* Prevents iOS auto-zoom */
  outline: none;
  transition: var(--trans);
}

input:focus, select:focus, textarea:focus {
  border-color: var(--accent);
  box-shadow: 0 0 0 4px rgba(0,255,255,0.1);
  background: rgba(0,255,255,0.05);
}

/* ── 5. Responsive Breakpoints ── */

/* TABLET (768px) */
@media (max-width: 1024px) {
  .grid3 { grid-template-columns: repeat(2, 1fr); }
  .grid4 { grid-template-columns: repeat(2, 1fr); }
}

@media (max-width: 768px) {
  .grid2, .grid3, .grid4 { grid-template-columns: 1fr; }
  
  .layout { flex-direction: column; }
  
  /* Sidebar Mobile Behavior */
  .sidebar { 
    width: 100% !important; 
    height: auto !important;
    position: static !important;
    transform: none !important;
    border-right: none; 
    border-bottom: 1px solid rgba(139,92,246,.1); 
    padding: 0.75rem 1rem !important; 
    display: flex !important; 
    overflow-x: auto; 
    gap: 0.5rem; 
    z-index: 100;
  }
  .sidebar .nav-section { display: none; }
  .sidebar .nav-item { 
    margin-bottom: 0; 
    white-space: nowrap; 
    padding: 0.5rem 0.8rem; 
    font-size: 0.75rem; 
    flex-shrink: 0;
  }
  .sidebar .nav-icon { margin-bottom: 0; margin-right: 6px; font-size: 0.85rem; }
  .sidebar .nav-item span:not(.nav-icon) { display: inline !important; }
  
  .content { padding: 1rem; }
  .grid2, .grid3, .grid4 { grid-template-columns: 1fr !important; }
  
  .top-right { font-size: 0.7rem; }
  
  /* Modal Overhaul */
  .modal-content {
    width: 95%;
    padding: 1.5rem;
    border-radius: 20px;
  }
  
  .quiz-history-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.25rem;
  }
  
  .qh-actions {
    width: 100%;
    display: grid !important;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
  }
  .qh-actions .btn { width: 100%; font-size: 0.65rem; }
}

/* MOBILE (480px) */
@media (max-width: 480px) {
  :root { --safe-padding: 1.25rem; }
  
  h1 { font-size: 1.3rem; }
  
  .glass { border-radius: 20px; }
  
  /* Modal Overhaul */
  .modal-content {
    width: 95%;
    padding: 1.5rem;
    border-radius: 20px;
  }
  
  .top-bar { padding: 1rem; }
  
  .quiz-history-item {
    flex-direction: column;
    align-items: flex-start;
    gap: 1.25rem;
  }
  
  .qh-actions {
    width: 100%;
    display: grid;
    grid-template-columns: 1fr 1fr;
    gap: 0.5rem;
  }
  
  .qh-actions .btn { width: 100%; font-size: 0.65rem; }
  
  /* Timer Scaling */
  .timer-svg { width: 80px; height: 80px; }
  .timer-text { font-size: 1.1rem; }
}

/* ── 6. Utility & UX ── */
.overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,0.5);
  backdrop-filter: blur(4px);
  z-index: 999;
  display: none;
  animation: fadeIn 0.3s ease;
}
.overlay.on { display: block; }

@keyframes fadeIn { from { opacity: 0; transform: translateY(10px); } to { opacity: 1; transform: translateY(0); } }
@keyframes spin { to { transform: rotate(360deg); } }

.spin {
  width: 18px; height: 18px;
  border: 2.5px solid rgba(0,255,255,0.1);
  border-top-color: currentColor;
  border-radius: 50%;
  animation: spin 0.8s linear infinite;
}

/* ── 7. Advanced Components (KPIs, Reviews, Toggles) ── */

/* KPI Cards */
.kpi-card { position: relative; overflow: hidden; background: var(--card-bg); border: 1px solid var(--glass-border); border-radius: 16px; padding: 1.5rem; transition: var(--trans); }
.kpi-card::before { content: ""; position: absolute; top: 0; right: 0; width: 60px; height: 60px; background: linear-gradient(135deg, transparent, var(--accent)); opacity: 0.1; }
.kpi-val { font-family: 'Orbitron', monospace; font-size: 1.8rem; font-weight: 700; color: var(--accent); display: block; margin-bottom: 0.25rem; }
.kpi-lbl { font-size: 0.65rem; text-transform: uppercase; letter-spacing: 1.5px; color: var(--sub-text); font-weight: 600; }
.kpi-sub { font-size: 0.6rem; color: var(--accent-alt); margin-top: 0.5rem; }

body.light-mode .kpi-card { border-color: var(--input-border); box-shadow: 0 4px 12px rgba(0, 0, 0, 0.06); }
body.light-mode .kpi-card::before { opacity: 0.6; }
body.light-mode .kpi-val { background: linear-gradient(135deg, var(--accent), var(--accent-alt)) !important; -webkit-background-clip: text !important; -webkit-text-fill-color: transparent !important; }
body.light-mode .kpi-lbl, body.light-mode .kpi-sub { color: var(--sub-text); }

/* SUBMISSION DRILL-DOWN STYLES */
.review-grid { display: grid; grid-template-columns: 1fr; gap: 1rem; max-height: 65vh; overflow-y: auto; padding-right: .5rem; }
.review-card { background: rgba(255,255,255,0.03); border: 1px solid rgba(139,92,246,0.15); border-radius: 12px; padding: 1.25rem; transition: var(--trans); }
.review-card.correct { border-left: 4px solid #4ade80; }
.review-card.wrong { border-left: 4px solid #ef4444; }
.review-header { display: flex; gap: .5rem; align-items: center; margin-bottom: .75rem; flex-wrap: wrap; }
.q-index { font-family: 'Orbitron', monospace; color: var(--accent); font-size: .85rem; font-weight: 700; }
.review-qtext { font-size: 1rem; color: var(--text); margin-bottom: 1rem; line-height: 1.5; font-weight: 500; }
.user-ans { padding: .6rem .8rem; border-radius: 8px; margin-bottom: .4rem; font-size: .85rem; }
.user-ans.wrong { background: rgba(239,68,68,0.08); color: #fca5a5; border: 1px solid rgba(239,68,68,0.2); }
.user-ans.correct { background: rgba(74,222,128,0.08); color: #4ade80; border: 1px solid rgba(74,222,128,0.2); }
.correct-ans { padding: .6rem .8rem; background: rgba(0,255,255,0.04); color: var(--accent-alt); border-radius: 8px; font-size: .85rem; border: 1px solid rgba(0,255,255,0.1); }

/* THEME SWITCH STYLES */
.theme-switch { --toggle-size: 20px; --container-width: 5.625em; --container-height: 2.5em; --container-radius: 6.25em; --container-light-bg: #3D7EAE; --container-night-bg: #1D1F2C; --circle-container-diameter: 3.375em; --sun-moon-diameter: 2.125em; --sun-bg: #ECCA2F; --moon-bg: #C4C9D1; --spot-color: #959DB1; --circle-container-offset: calc((var(--circle-container-diameter) - var(--container-height)) / 2 * -1); --stars-color: #fff; --clouds-color: #F3FDFF; --back-clouds-color: #AACADF; --transition: .5s cubic-bezier(0, -0.02, 0.4, 1.25); --circle-transition: .3s cubic-bezier(0, -0.02, 0.35, 1.17); }
.theme-switch, .theme-switch *, .theme-switch *::before, .theme-switch *::after { box-sizing: border-box; margin: 0; padding: 0; font-size: var(--toggle-size); }
.theme-switch__container { width: var(--container-width); height: var(--container-height); background-color: var(--container-light-bg); border-radius: var(--container-radius); overflow: hidden; cursor: pointer; box-shadow: 0em -0.062em 0.062em rgba(0, 0, 0, 0.25), 0em 0.062em 0.125em rgba(255, 255, 255, 0.94); transition: var(--transition); position: relative; }
.theme-switch__container::before { content: ""; position: absolute; z-index: 1; inset: 0; box-shadow: 0em 0.05em 0.187em rgba(0, 0, 0, 0.25) inset, 0em 0.05em 0.187em rgba(0, 0, 0, 0.25) inset; border-radius: var(--container-radius); }
.theme-switch__checkbox { display: none; }
.theme-switch__circle-container { width: var(--circle-container-diameter); height: var(--circle-container-diameter); background-color: rgba(255, 255, 255, 0.1); position: absolute; left: var(--circle-container-offset); top: var(--circle-container-offset); border-radius: var(--container-radius); box-shadow: inset 0 0 0 3.375em rgba(255, 255, 255, 0.1), inset 0 0 0 3.375em rgba(255, 255, 255, 0.1), 0 0 0 0.625em rgba(255, 255, 255, 0.1), 0 0 0 1.25em rgba(255, 255, 255, 0.1); display: flex; transition: var(--circle-transition); pointer-events: none; }
.theme-switch__sun-moon-container { pointer-events: auto; position: relative; z-index: 2; width: var(--sun-moon-diameter); height: var(--sun-moon-diameter); margin: auto; border-radius: var(--container-radius); background-color: var(--sun-bg); box-shadow: 0.062em 0.062em 0.062em 0em rgba(254, 255, 239, 0.61) inset, 0em -0.062em 0.062em 0em #a1872a inset; filter: drop-shadow(0.062em 0.125em 0.125em rgba(0, 0, 0, 0.25)) drop-shadow(0em 0.062em 0.125em rgba(0, 0, 0, 0.25)); overflow: hidden; transition: var(--transition); }
.theme-switch__moon { transform: translateX(100%); width: 100%; height: 100%; background-color: var(--moon-bg); border-radius: inherit; box-shadow: 0.062em 0.062em 0.062em 0em rgba(254, 255, 239, 0.61) inset, 0em -0.062em 0.062em 0em #969696 inset; transition: var(--transition); position: relative; }
.theme-switch__spot { position: absolute; top: 0.75em; left: 0.312em; width: 0.75em; height: 0.75em; border-radius: var(--container-radius); background-color: var(--spot-color); box-shadow: 0em 0.0312em 0.062em rgba(0, 0, 0, 0.25) inset; }
.theme-switch__spot:nth-of-type(2) { width: 0.375em; height: 0.375em; top: 0.937em; left: 1.375em; }
.theme-switch__spot:nth-last-of-type(3) { width: 0.25em; height: 0.25em; top: 0.312em; left: 0.812em; }
.theme-switch__clouds { width: 1.25em; height: 1.25em; background-color: var(--clouds-color); border-radius: var(--container-radius); position: absolute; bottom: -0.625em; left: 0.312em; box-shadow: 0.937em 0.312em var(--clouds-color), -0.312em -0.312em var(--back-clouds-color), 1.437em 0.375em var(--clouds-color), 0.5em -0.125em var(--back-clouds-color), 2.187em 0 var(--clouds-color), 1.25em -0.062em var(--back-clouds-color), 2.937em 0.312em var(--clouds-color), 2em -0.312em var(--back-clouds-color), 3.625em -0.062em var(--clouds-color), 2.625em 0em var(--back-clouds-color), 4.5em -0.312em var(--clouds-color), 3.375em -0.437em var(--back-clouds-color), 4.625em -1.75em 0 0.437em var(--clouds-color), 4em -0.625em var(--back-clouds-color), 4.125em -2.125em 0 0.437em var(--back-clouds-color); transition: 0.5s cubic-bezier(0, -0.02, 0.4, 1.25); }
.theme-switch__stars-container { position: absolute; color: var(--stars-color); top: -100%; left: 0.312em; width: 2.75em; height: auto; transition: var(--transition); }
.theme-switch__checkbox:checked + .theme-switch__container { background-color: var(--container-night-bg); }
.theme-switch__checkbox:checked + .theme-switch__container .theme-switch__circle-container { left: calc(100% - var(--circle-container-offset) - var(--circle-container-diameter)); }
.theme-switch__checkbox:checked + .theme-switch__container .theme-switch__circle-container:hover { left: calc(100% - var(--circle-container-offset) - var(--circle-container-diameter) - 0.187em); }
.theme-switch__circle-container:hover { left: calc(var(--circle-container-offset) + 0.187em); }
.theme-switch__checkbox:checked + .theme-switch__container .theme-switch__moon { transform: translate(0); }
.theme-switch__checkbox:checked + .theme-switch__container .theme-switch__clouds { bottom: -4.062em; }
.theme-switch__checkbox:checked + .theme-switch__container .theme-switch__stars-container { top: 50%; transform: translateY(-50%); }

/* Toasts */
.toast {
  position: fixed;
  bottom: 2rem;
  left: 50%;
  transform: translateX(-50%) translateY(100px);
  z-index: 9999;
  padding: 1rem 1.5rem;
  border-radius: 14px;
  backdrop-filter: blur(16px);
  transition: transform 0.4s cubic-bezier(0.175, 0.885, 0.32, 1.275);
  box-shadow: 0 10px 30px rgba(0,0,0,0.4);
}
.toast.show { transform: translateX(-50%) translateY(0); }

/* Accessibility */
.sr-only { position: absolute; width: 1px; height: 1px; padding: 0; margin: -1px; overflow: hidden; clip: rect(0,0,0,0); border: 0; }

/* Focus rings for keyboard navigation */
input:focus-visible, select:focus-visible, textarea:focus-visible, button:focus-visible, a:focus-visible, [tabindex]:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 3px;
}

@media (prefers-reduced-motion: reduce) {
  *, *::before, *::after {
    animation-delay: -1ms !important;
    animation-duration: 1ms !important;
    animation-iteration-count: 1 !important;
    background-attachment: initial !important;
    scroll-behavior: auto !important;
    transition-duration: 0s !important;
    transition-delay: 0s !important;
  }
  .orb {
    display: none !important;
  }
}