/* ===================================================
   BsCsX Student Web Portal - Modern Styling
   =================================================== */

:root {
  --primary: #FF6B4A;
  --primary-hover: #E05333;
  --primary-glow: rgba(255, 107, 74, 0.25);
  --secondary: #8B5CF6;
  --accent: #24B870;
  --accent-glow: rgba(36, 184, 112, 0.25);
  --warning: #F59E0B;
  --danger: #EF4444;

  /* Dark Mode Default */
  --bg: #0B0F18;
  --bg-subtle: #101622;
  --surface: #151B26;
  --surface-hover: #1C2433;
  --surface-border: #2A3342;
  --surface-border-subtle: #1F2735;
  --text-primary: #F8FAFC;
  --text-secondary: #94A3B8;
  --text-muted: #64748B;
  --glass-bg: rgba(21, 27, 38, 0.85);
  --glass-border: rgba(42, 51, 66, 0.6);
  --shadow-sm: 0 2px 8px rgba(0, 0, 0, 0.3);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.4);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.6);
  --font: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
}

[data-theme="light"] {
  --bg: #FFF8F1;
  --bg-subtle: #FDF1E6;
  --surface: #FFFFFF;
  --surface-hover: #FFF3EB;
  --surface-border: #F3E5D8;
  --surface-border-subtle: #EAD8C7;
  --text-primary: #1F2937;
  --text-secondary: #4B5563;
  --text-muted: #9CA3AF;
  --glass-bg: rgba(255, 255, 255, 0.9);
  --glass-border: rgba(243, 229, 216, 0.8);
  --shadow-sm: 0 2px 8px rgba(255, 107, 74, 0.06);
  --shadow-md: 0 8px 24px rgba(0, 0, 0, 0.08);
  --shadow-lg: 0 16px 40px rgba(0, 0, 0, 0.12);
}

* {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
  font-family: var(--font);
  -webkit-font-smoothing: antialiased;
}

body {
  background-color: var(--bg);
  color: var(--text-primary);
  min-height: 100vh;
  display: flex;
  flex-direction: column;
  overflow-x: hidden;
  transition: background-color 0.25s ease, color 0.25s ease;
}

/* Scrollbar */
::-webkit-scrollbar {
  width: 8px;
  height: 8px;
}
::-webkit-scrollbar-track {
  background: var(--bg-subtle);
}
::-webkit-scrollbar-thumb {
  background: var(--surface-border);
  border-radius: 4px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--primary);
}

/* Buttons */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  padding: 9px 18px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  cursor: pointer;
  border: 1px solid transparent;
  transition: all 0.2s cubic-bezier(0.4, 0, 0.2, 1);
  text-decoration: none;
  user-select: none;
}
.btn:hover {
  transform: translateY(-1px);
}
.btn:active {
  transform: translateY(1px);
}
.btn-primary {
  background: linear-gradient(135deg, var(--primary) 0%, #FF8566 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 14px var(--primary-glow);
}
.btn-primary:hover {
  background: linear-gradient(135deg, var(--primary-hover) 0%, #FF6B4A 100%);
  box-shadow: 0 6px 20px var(--primary-glow);
}
.btn-secondary {
  background: var(--surface);
  color: var(--text-primary);
  border-color: var(--surface-border);
}
.btn-secondary:hover {
  background: var(--surface-hover);
  border-color: var(--primary);
}
.btn-accent {
  background: linear-gradient(135deg, var(--accent) 0%, #34D399 100%);
  color: #FFFFFF;
  box-shadow: 0 4px 14px var(--accent-glow);
}
.btn-sm {
  padding: 6px 12px;
  font-size: 12.5px;
  border-radius: 8px;
}

/* Header */
.app-header {
  position: sticky;
  top: 0;
  z-index: 50;
  background: var(--glass-bg);
  backdrop-filter: blur(16px);
  -webkit-backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--glass-border);
  padding: 12px 24px;
}
.header-container {
  max-width: 1280px;
  margin: 0 auto;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
}
.brand-group {
  display: flex;
  align-items: center;
  gap: 12px;
}
.brand-logo {
  width: 42px;
  height: 42px;
  border-radius: 10px;
  box-shadow: 0 4px 12px rgba(255, 107, 74, 0.3);
  object-fit: cover;
}
.brand-title {
  font-size: 20px;
  font-weight: 800;
  letter-spacing: -0.5px;
  display: flex;
  align-items: center;
  gap: 2px;
}
.brand-title .brand-x {
  color: var(--primary);
  background: linear-gradient(135deg, var(--primary) 0%, var(--secondary) 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
}
.brand-badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  letter-spacing: 0.5px;
  background: rgba(255, 107, 74, 0.12);
  color: var(--primary);
  border: 1px solid rgba(255, 107, 74, 0.25);
  padding: 2px 8px;
  border-radius: 20px;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 10px;
}

/* Status Pill */
.status-pill {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: 20px;
  font-size: 12px;
  font-weight: 600;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  color: var(--text-secondary);
}
.status-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--accent);
  box-shadow: 0 0 8px var(--accent);
  animation: pulse-dot 2s infinite ease-in-out;
}
.status-dot.offline {
  background: var(--warning);
  box-shadow: 0 0 8px var(--warning);
  animation: none;
}
@keyframes pulse-dot {
  0%, 100% { opacity: 1; transform: scale(1); }
  50% { opacity: 0.5; transform: scale(0.85); }
}

/* PWA Install Guidance Banner */
.install-banner {
  background: linear-gradient(90deg, rgba(255, 107, 74, 0.15) 0%, rgba(139, 92, 246, 0.15) 100%);
  border-bottom: 1px solid rgba(255, 107, 74, 0.3);
  padding: 12px 24px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  animation: fadeIn 0.4s ease-out;
}
.install-banner-inner {
  max-width: 1280px;
  margin: 0 auto;
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  flex-wrap: wrap;
}
.install-text {
  display: flex;
  align-items: center;
  gap: 12px;
}
.install-icon-badge {
  font-size: 24px;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  width: 44px;
  height: 44px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  box-shadow: var(--shadow-sm);
}
.install-title {
  font-weight: 700;
  font-size: 14.5px;
  color: var(--text-primary);
}
.install-desc {
  font-size: 12.5px;
  color: var(--text-secondary);
}
.install-cta-group {
  display: flex;
  align-items: center;
  gap: 8px;
}

/* Main Container */
.main-wrapper {
  max-width: 1280px;
  margin: 0 auto;
  width: 100%;
  padding: 24px;
  flex: 1;
}

/* Message of the Day Card */
.motd-card {
  background: linear-gradient(135deg, rgba(139, 92, 246, 0.12) 0%, rgba(255, 107, 74, 0.08) 100%);
  border: 1px solid rgba(139, 92, 246, 0.25);
  border-radius: 16px;
  padding: 18px 22px;
  margin-bottom: 24px;
  display: flex;
  align-items: flex-start;
  gap: 16px;
  box-shadow: var(--shadow-sm);
  position: relative;
  overflow: hidden;
}
.motd-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  width: 4px;
  height: 100%;
  background: linear-gradient(to bottom, var(--secondary), var(--primary));
}
.motd-icon {
  font-size: 26px;
  margin-top: 2px;
}
.motd-content {
  flex: 1;
}
.motd-badge {
  font-size: 11px;
  font-weight: 700;
  text-transform: uppercase;
  color: var(--secondary);
  letter-spacing: 0.5px;
  margin-bottom: 4px;
}
.motd-text {
  font-size: 14.5px;
  font-weight: 500;
  color: var(--text-primary);
  line-height: 1.5;
}

/* Navigation Tabs */
.nav-tabs {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 24px;
  border-bottom: 1px solid var(--surface-border);
  padding-bottom: 8px;
  overflow-x: auto;
}
.nav-tab-btn {
  background: transparent;
  border: none;
  padding: 10px 18px;
  border-radius: 10px;
  font-size: 14px;
  font-weight: 600;
  color: var(--text-secondary);
  cursor: pointer;
  display: flex;
  align-items: center;
  gap: 8px;
  transition: all 0.2s ease;
  white-space: nowrap;
}
.nav-tab-btn:hover {
  color: var(--text-primary);
  background: var(--surface-hover);
}
.nav-tab-btn.active {
  color: #FFFFFF;
  background: linear-gradient(135deg, var(--primary) 0%, #FF8566 100%);
  box-shadow: 0 4px 12px var(--primary-glow);
}
.nav-tab-btn .tab-count {
  font-size: 11px;
  padding: 2px 7px;
  border-radius: 12px;
  background: rgba(0, 0, 0, 0.2);
}

/* Controls Bar (Search & Filter) */
.controls-bar {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  margin-bottom: 24px;
  flex-wrap: wrap;
}
.search-box {
  position: relative;
  flex: 1;
  min-width: 260px;
}
.search-input {
  width: 100%;
  padding: 11px 16px 11px 42px;
  border-radius: 12px;
  background: var(--surface);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  font-size: 14px;
  outline: none;
  transition: all 0.2s ease;
}
.search-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}
.search-icon {
  position: absolute;
  left: 14px;
  top: 50%;
  transform: translateY(-50%);
  color: var(--text-muted);
  font-size: 16px;
  pointer-events: none;
}

/* Grid Layouts */
.subjects-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(340px, 1fr));
  gap: 20px;
}

/* Subject Card */
.subject-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 16px;
  padding: 20px;
  display: flex;
  flex-direction: column;
  justify-content: space-between;
  transition: all 0.25s cubic-bezier(0.4, 0, 0.2, 1);
  position: relative;
  overflow: hidden;
  box-shadow: var(--shadow-sm);
}
.subject-card:hover {
  transform: translateY(-4px);
  border-color: var(--surface-border-subtle);
  box-shadow: var(--shadow-md);
}
.subject-card-accent {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 4px;
}
.subject-header {
  display: flex;
  align-items: flex-start;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}
.subject-icon-box {
  width: 44px;
  height: 44px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  font-weight: 700;
  color: #FFFFFF;
}
.subject-title {
  font-size: 17px;
  font-weight: 700;
  color: var(--text-primary);
  line-height: 1.3;
  margin-bottom: 6px;
}
.subject-code {
  font-size: 12.5px;
  font-weight: 600;
  color: var(--text-secondary);
}
.subject-notes-count {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 14px;
  display: flex;
  align-items: center;
  gap: 6px;
}
.subject-actions {
  display: flex;
  gap: 8px;
  margin-top: 18px;
}
.subject-actions .btn {
  flex: 1;
}

/* Notes List / Schedule Cards */
.resource-list {
  display: flex;
  flex-direction: column;
  gap: 12px;
}
.resource-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 14px;
  padding: 16px 20px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  transition: all 0.2s ease;
}
.resource-card:hover {
  border-color: var(--primary);
  background: var(--surface-hover);
}
.resource-info {
  display: flex;
  align-items: center;
  gap: 14px;
  flex: 1;
  min-width: 0;
}
.resource-icon {
  width: 40px;
  height: 40px;
  border-radius: 10px;
  background: rgba(255, 107, 74, 0.12);
  color: var(--primary);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 20px;
  flex-shrink: 0;
}
.resource-title {
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.resource-meta {
  font-size: 12.5px;
  color: var(--text-muted);
  display: flex;
  align-items: center;
  gap: 8px;
  margin-top: 2px;
}
.resource-badge-cached {
  font-size: 11px;
  font-weight: 700;
  color: var(--accent);
  background: rgba(36, 184, 112, 0.12);
  border: 1px solid rgba(36, 184, 112, 0.25);
  padding: 2px 7px;
  border-radius: 10px;
}
.resource-actions {
  display: flex;
  align-items: center;
  gap: 8px;
  flex-shrink: 0;
}

/* Fullscreen Reader Modal */
.modal-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0, 0, 0, 0.85);
  backdrop-filter: blur(8px);
  -webkit-backdrop-filter: blur(8px);
  z-index: 100;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  animation: fadeIn 0.2s ease-out;
}
.modal-overlay.hidden {
  display: none;
}
.modal-container {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 18px;
  width: 100%;
  max-width: 1100px;
  height: 90vh;
  display: flex;
  flex-direction: column;
  box-shadow: var(--shadow-lg);
  overflow: hidden;
}
.modal-header {
  padding: 14px 20px;
  border-bottom: 1px solid var(--surface-border);
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  background: var(--bg-subtle);
}
.modal-title-group {
  display: flex;
  align-items: center;
  gap: 10px;
  min-width: 0;
}
.modal-title {
  font-size: 16px;
  font-weight: 700;
  white-space: nowrap;
  overflow: hidden;
  text-overflow: ellipsis;
}
.modal-body {
  flex: 1;
  position: relative;
  background: #111;
}
.pdf-frame {
  width: 100%;
  height: 100%;
  border: none;
}

/* Lock Screen */
.lock-screen-wrapper {
  position: fixed;
  inset: 0;
  background: var(--bg);
  z-index: 999;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 24px;
}
.lock-card {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  border-radius: 24px;
  width: 100%;
  max-width: 440px;
  padding: 36px 32px;
  box-shadow: var(--shadow-lg);
  text-align: center;
  position: relative;
  overflow: hidden;
}
.lock-card::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 5px;
  background: linear-gradient(90deg, var(--primary) 0%, var(--secondary) 100%);
}
.lock-logo {
  width: 68px;
  height: 68px;
  border-radius: 18px;
  box-shadow: 0 8px 24px var(--primary-glow);
  margin-bottom: 16px;
}
.lock-title {
  font-size: 24px;
  font-weight: 800;
  margin-bottom: 8px;
}
.lock-subtitle {
  font-size: 13.5px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 24px;
}
.lock-input-group {
  position: relative;
  margin-bottom: 16px;
}
.lock-input {
  width: 100%;
  padding: 13px 18px;
  border-radius: 12px;
  background: var(--bg-subtle);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  font-size: 15px;
  text-align: center;
  letter-spacing: 1px;
  outline: none;
  transition: all 0.2s ease;
}
.lock-input:focus {
  border-color: var(--primary);
  box-shadow: 0 0 0 3px var(--primary-glow);
}
.lock-error {
  color: var(--danger);
  font-size: 13px;
  font-weight: 600;
  margin-top: 8px;
  display: none;
}
.lock-hint {
  font-size: 12px;
  color: var(--text-muted);
  margin-top: 18px;
  line-height: 1.4;
}

/* PWA Guidance Modal */
.guide-modal-content {
  max-width: 580px;
  height: auto;
  max-height: 85vh;
  padding: 24px;
  overflow-y: auto;
}
.guide-step {
  display: flex;
  gap: 14px;
  margin-bottom: 20px;
  background: var(--bg-subtle);
  border: 1px solid var(--surface-border);
  border-radius: 14px;
  padding: 16px;
}
.guide-step-num {
  width: 32px;
  height: 32px;
  border-radius: 50%;
  background: var(--primary);
  color: #fff;
  font-weight: 800;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
}
.guide-step-body h4 {
  font-size: 15px;
  margin-bottom: 4px;
}
.guide-step-body p {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.4;
}

/* Animations */
@keyframes fadeIn {
  from { opacity: 0; transform: translateY(6px); }
  to { opacity: 1; transform: translateY(0); }
}
.shake {
  animation: shake 0.4s ease-in-out;
}
@keyframes shake {
  0%, 100% { transform: translateX(0); }
  20%, 60% { transform: translateX(-8px); }
  40%, 80% { transform: translateX(8px); }
}

/* Toast Notifications */
.toast-container {
  position: fixed;
  bottom: 24px;
  right: 24px;
  z-index: 200;
  display: flex;
  flex-direction: column;
  gap: 8px;
}
.toast {
  background: var(--surface);
  border: 1px solid var(--surface-border);
  color: var(--text-primary);
  padding: 12px 18px;
  border-radius: 12px;
  font-size: 13.5px;
  font-weight: 600;
  box-shadow: var(--shadow-md);
  display: flex;
  align-items: center;
  gap: 10px;
  animation: fadeIn 0.25s ease-out;
}

/* Responsive */
@media (max-width: 768px) {
  .app-header { padding: 12px 16px; }
  .main-wrapper { padding: 16px; }
  .subjects-grid { grid-template-columns: 1fr; }
  .install-banner { padding: 12px 16px; }
  .install-banner-inner { flex-direction: column; align-items: stretch; }
  .install-cta-group { justify-content: stretch; }
  .install-cta-group .btn { flex: 1; }
  .modal-container { height: 95vh; margin: 10px; }
}