/* ===== RESET & BASE ===== */
*,
*::before,
*::after {
  box-sizing: border-box;
  margin: 0;
  padding: 0;
}

:root {
  --bg-base: #0a0d12;
  --bg-surface: #0f1319;
  --bg-card: #141a23;
  --bg-hover: #1a2230;
  --bg-active: #1e2a3a;

  --border-subtle: rgba(255, 255, 255, 0.05);
  --border-mid: rgba(255, 255, 255, 0.1);
  --border-strong: rgba(255, 255, 255, 0.18);

  --text-primary: #e8edf5;
  --text-secondary: #8a97a8;
  --text-muted: #4e5a6a;
  --text-accent: #5b9cf6;

  --accent-blue: #5b9cf6;
  --accent-teal: #2dd4bf;
  --accent-amber: #f59e0b;
  --accent-purple: #a78bfa;
  --accent-coral: #fb7185;
  --accent-green: #34d399;
  --accent-orange: #fb923c;
  --accent-sky: #38bdf8;

  --tag-python-bg: rgba(52, 211, 153, 0.12);
  --tag-python-color: #34d399;
  --tag-dl-bg: rgba(91, 156, 246, 0.12);
  --tag-dl-color: #5b9cf6;
  --tag-llm-bg: rgba(245, 158, 11, 0.12);
  --tag-llm-color: #f59e0b;
  --tag-mlops-bg: rgba(167, 139, 250, 0.12);
  --tag-mlops-color: #a78bfa;
  --tag-cv-bg: rgba(251, 113, 133, 0.12);
  --tag-cv-color: #fb7185;
  --tag-sys-bg: rgba(45, 212, 191, 0.12);
  --tag-sys-color: #2dd4bf;
  --tag-proj-bg: rgba(251, 146, 60, 0.12);
  --tag-proj-color: #fb923c;
  --tag-rev-bg: rgba(78, 90, 106, 0.15);
  --tag-rev-color: #8a97a8;

  --font-display: "Syne", sans-serif;
  --font-title: "Space Grotesk", "Syne", sans-serif;
  --font-body: "Inter", sans-serif;
  --font-mono: "JetBrains Mono", monospace;

  --radius-sm: 6px;
  --radius-md: 10px;
  --radius-lg: 16px;
  --radius-xl: 24px;
}

html {
  scroll-behavior: smooth;
}

body {
  font-family: var(--font-body);
  background: var(--bg-base);
  color: var(--text-primary);
  min-height: 100vh;
  font-size: 15px;
  line-height: 1.6;
  overflow-x: hidden;
  position: relative;
}

/* ===== BACKGROUND EFFECTS ===== */
.bg-grid {
  position: fixed;
  inset: 0;
  background-image: linear-gradient(rgba(91, 156, 246, 0.03) 1px, transparent 1px), linear-gradient(90deg, rgba(91, 156, 246, 0.03) 1px, transparent 1px);
  background-size: 48px 48px;
  pointer-events: none;
  z-index: 0;
}

.noise-overlay {
  position: fixed;
  inset: 0;
  opacity: 0.025;
  background-image: url("data:image/svg+xml,%3Csvg viewBox='0 0 256 256' xmlns='http://www.w3.org/2000/svg'%3E%3Cfilter id='noise'%3E%3CfeTurbulence type='fractalNoise' baseFrequency='0.9' numOctaves='4' stitchTiles='stitch'/%3E%3C/filter%3E%3Crect width='100%25' height='100%25' filter='url(%23noise)'/%3E%3C/svg%3E");
  pointer-events: none;
  z-index: 0;
}

/* ===== HEADER ===== */
.site-header {
  position: sticky;
  top: 0;
  z-index: 100;
  background: rgba(10, 13, 18, 0.85);
  backdrop-filter: blur(20px);
  -webkit-backdrop-filter: blur(20px);
  border-bottom: 1px solid var(--border-subtle);
}

.header-inner {
  max-width: 1600px;
  margin: 0 auto;
  padding: 16px 32px;
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 24px;
}

.header-left {
  display: flex;
  align-items: center;
  gap: 20px;
  flex-wrap: wrap;
}

.logo-mark {
  display: flex;
  align-items: center;
  gap: 10px;
}

.logo-icon {
  font-size: 24px;
  color: var(--accent-blue);
  animation: pulse 3s ease-in-out infinite;
}

@keyframes pulse {
  0%,
  100% {
    opacity: 1;
    transform: scale(1);
  }
  50% {
    opacity: 0.7;
    transform: scale(0.95);
  }
}

.logo-text {
  font-family: var(--font-title);
  font-size: 22px;
  font-weight: 800;
  letter-spacing: 1px;
  background: linear-gradient(135deg, #e8edf5 0%, #5b9cf6 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.header-meta {
  display: flex;
  gap: 8px;
  flex-wrap: wrap;
}

.meta-pill {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  padding: 4px 10px;
  border-radius: 20px;
  background: var(--bg-card);
  border: 1px solid var(--border-mid);
  color: var(--text-secondary);
  letter-spacing: 0.02em;
}

.header-right {
  display: flex;
  align-items: center;
  gap: 24px;
}

/* Progress Ring */
.progress-ring-container {
  position: relative;
  width: 64px;
  height: 64px;
}

.ring-bg {
  stroke: var(--border-mid);
}
.ring-fill {
  stroke: var(--accent-blue);
  stroke-linecap: round;
  transform: rotate(-90deg);
  transform-origin: center;
  transition: stroke-dashoffset 0.6s ease;
  filter: drop-shadow(0 0 6px rgba(91, 156, 246, 0.5));
}

.ring-label {
  position: absolute;
  inset: 0;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  font-family: var(--font-mono);
}

.ring-label span {
  font-size: 14px;
  font-weight: 600;
  color: var(--accent-blue);
  line-height: 1;
}

.ring-label small {
  font-size: 9px;
  color: var(--text-muted);
}

.header-stats {
  display: flex;
  gap: 20px;
}

.stat-item {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 2px;
}

.stat-num {
  font-family: var(--font-mono);
  font-size: 18px;
  font-weight: 600;
  color: var(--text-primary);
  line-height: 1;
}

.stat-label {
  font-size: 11px;
  color: var(--text-muted);
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

/* ===== TOOLBAR ===== */
.toolbar {
  position: sticky;
  top: 104px;
  z-index: 90;
  background: rgba(10, 13, 18, 0.9);
  backdrop-filter: blur(16px);
  border-bottom: 1px solid var(--border-subtle);
}

.toolbar-inner {
  max-width: 1600px;
  margin: 0 auto;
  padding: 12px 32px;
  display: flex;
  align-items: center;
  gap: 16px;
  flex-wrap: wrap;
}

.search-wrap {
  position: relative;
  min-width: 220px;
  flex-shrink: 0;
}

.search-icon {
  position: absolute;
  left: 12px;
  top: 50%;
  transform: translateY(-50%);
  font-size: 18px;
  color: var(--text-muted);
  pointer-events: none;
}

.search-input {
  width: 100%;
  background: var(--bg-card);
  border: 1px solid var(--border-mid);
  border-radius: var(--radius-md);
  padding: 9px 12px 9px 38px;
  color: var(--text-primary);
  font-family: var(--font-body);
  font-size: 14px;
  outline: none;
  transition:
    border-color 0.2s,
    box-shadow 0.2s;
}

.search-input::placeholder {
  color: var(--text-muted);
}
.search-input:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(91, 156, 246, 0.12);
}

.filter-group {
  display: flex;
  gap: 6px;
  flex-wrap: wrap;
}

/* Ensure [hidden] always hides elements regardless of CSS specificity */
[hidden] {
  display: none !important;
}

/* Mode-based visibility for header meta and filter groups */
.mode-ai #headerMetaDsa,
.mode-ai #filterGroupDsa,
.mode-ai #statTopicsWrap {
  display: none !important;
}

.mode-dsa #headerMetaAi,
.mode-dsa #filterGroupAi,
.mode-dsa #statDaysWrap {
  display: none !important;
}

.filter-btn {
  font-family: var(--font-body);
  font-size: 13px;
  font-weight: 500;
  padding: 7px 14px;
  border-radius: 20px;
  border: 1px solid var(--border-mid);
  background: transparent;
  color: var(--text-secondary);
  cursor: pointer;
  transition: all 0.2s;
  white-space: nowrap;
}

.filter-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--border-strong);
}

.filter-btn.active {
  background: rgba(91, 156, 246, 0.15);
  color: var(--accent-blue);
  border-color: rgba(91, 156, 246, 0.4);
}

/* Sync (export / import) */
.sync-group {
  display: flex;
  gap: 6px;
  align-items: center;
  flex-shrink: 0;
}

.sync-btn {
  font-family: var(--font-body);
  font-size: 12px;
  font-weight: 600;
  padding: 7px 12px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-mid);
  background: var(--bg-card);
  color: var(--text-secondary);
  cursor: pointer;
  transition: background 0.2s, border-color 0.2s, color 0.2s;
  white-space: nowrap;
}

.sync-btn:hover {
  background: var(--bg-hover);
  color: var(--text-primary);
  border-color: var(--border-strong);
}

.sync-btn--ghost {
  background: transparent;
}

.sync-btn--primary {
  background: rgba(91, 156, 246, 0.15);
  color: var(--accent-blue);
  border-color: rgba(91, 156, 246, 0.4);
}

.sync-btn--primary:hover {
  background: rgba(91, 156, 246, 0.22);
  color: var(--accent-blue);
}

.import-dialog {
  max-width: min(520px, calc(100vw - 32px));
  width: 100%;
  padding: 0;
  border: 1px solid var(--border-mid);
  border-radius: var(--radius-lg);
  background: var(--bg-surface);
  color: var(--text-primary);
  box-shadow: 0 24px 80px rgba(0, 0, 0, 0.55);
}

.import-dialog::backdrop {
  background: rgba(0, 0, 0, 0.65);
  backdrop-filter: blur(4px);
}

.import-dialog-form {
  padding: 20px 22px 18px;
}

.import-dialog-title {
  font-family: var(--font-display);
  font-size: 16px;
  font-weight: 700;
  margin-bottom: 8px;
  letter-spacing: 0.02em;
}

.import-dialog-hint {
  font-size: 13px;
  color: var(--text-secondary);
  line-height: 1.5;
  margin-bottom: 14px;
}

.import-textarea {
  width: 100%;
  min-height: 180px;
  resize: vertical;
  font-family: var(--font-mono);
  font-size: 12px;
  line-height: 1.45;
  padding: 12px 14px;
  border-radius: var(--radius-md);
  border: 1px solid var(--border-mid);
  background: var(--bg-base);
  color: var(--text-primary);
  outline: none;
}

.import-textarea:focus {
  border-color: var(--accent-blue);
  box-shadow: 0 0 0 3px rgba(91, 156, 246, 0.12);
}

.import-error {
  margin-top: 10px;
  font-size: 13px;
  color: var(--accent-coral);
}

.import-dialog-actions {
  display: flex;
  justify-content: flex-end;
  gap: 8px;
  margin-top: 16px;
  flex-wrap: wrap;
}

.sync-toast {
  position: fixed;
  bottom: 24px;
  left: 50%;
  transform: translateX(-50%) translateY(8px);
  z-index: 200;
  padding: 10px 18px;
  border-radius: 999px;
  font-size: 13px;
  font-weight: 500;
  color: var(--text-primary);
  background: var(--bg-card);
  border: 1px solid var(--border-mid);
  box-shadow: 0 12px 40px rgba(0, 0, 0, 0.45);
  opacity: 0;
  pointer-events: none;
  transition: opacity 0.25s ease, transform 0.25s ease;
}

.sync-toast.is-visible {
  opacity: 1;
  transform: translateX(-50%) translateY(0);
}

/* ===== MAIN CONTENT ===== */
.main-content {
  position: relative;
  z-index: 1;
  max-width: 1600px;
  margin: 0 auto;
  padding: 32px 32px 64px;
}

.table-scroll-wrap {
  overflow-x: auto;
  border-radius: var(--radius-lg);
  border: 1px solid var(--border-subtle);
  background: var(--bg-surface);
}

/* ===== TABLE ===== */
.roadmap-table {
  width: 100%;
  border-collapse: separate;
  border-spacing: 0;
  min-width: 980px;
}

/* Header */
.roadmap-table thead th {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.08em;
  text-transform: uppercase;
  color: var(--text-muted);
  padding: 14px 18px;
  text-align: left;
  background: var(--bg-card);
  border-bottom: 1px solid var(--border-mid);
  white-space: nowrap;
  position: sticky;
  top: 0;
}

.roadmap-table thead th:first-child {
  border-radius: var(--radius-lg) 0 0 0;
}
.roadmap-table thead th:last-child {
  border-radius: 0 var(--radius-lg) 0 0;
}

/* Columns */
.col-check {
  width: 52px;
}
.col-day {
  width: 88px;
}
.col-topic {
  width: 200px;
  min-width: 180px;
}
.col-tasks {
  min-width: 360px;
}
.col-tags {
  width: 200px;
  min-width: 160px;
}
.col-resources {
  min-width: 260px;
}
.col-hrs {
  width: 72px;
}

/* Phase header rows */
.phase-header-row td {
  background: var(--bg-base);
  padding: 20px 18px 10px;
  font-family: var(--font-display);
  font-size: 13px;
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  border-top: 1px solid var(--border-subtle);
}

.phase-header-row:first-of-type td {
  border-top: none;
}

.phase-label-text {
  display: inline-flex;
  align-items: center;
  gap: 10px;
}

.phase-line {
  display: inline-block;
  height: 1px;
  width: 40px;
  background: currentColor;
  opacity: 0.3;
  vertical-align: middle;
}

/* Data rows */
.day-row {
  transition: background 0.15s;
  border-bottom: 1px solid var(--border-subtle);
}

.day-row:hover {
  background: var(--bg-hover);
}

.day-row:last-child {
  border-bottom: none;
}

.day-row td {
  padding: 16px 18px;
  vertical-align: top;
  font-size: 14px;
  line-height: 1.6;
}

.day-row.is-done {
  opacity: 0.4;
}
.day-row.is-done .day-num-badge {
  text-decoration: line-through;
}
.day-row.is-done:hover {
  opacity: 0.6;
}

.day-row.hidden {
  display: none;
}

.dsa-row.hidden,
.dsa-topic-row.hidden {
  display: none;
}

/* Checkbox */
.done-checkbox {
  width: 20px;
  height: 20px;
  cursor: pointer;
  accent-color: var(--accent-blue);
  margin-top: 2px;
}

/* Day badge */
.day-num-badge {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  padding: 4px 9px;
  border-radius: var(--radius-sm);
  background: var(--bg-active);
  color: var(--text-secondary);
  border: 1px solid var(--border-mid);
  white-space: nowrap;
}

/* Topic cell */
.topic-name {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
  margin-bottom: 2px;
}

/* Tasks cell */
.tasks-list {
  list-style: none;
  display: flex;
  flex-direction: column;
  gap: 6px;
}

.task-item {
  display: flex;
  gap: 10px;
  align-items: flex-start;
}

.task-checkbox {
  flex-shrink: 0;
  width: 14px;
  height: 14px;
  margin-top: 3px;
  cursor: pointer;
  accent-color: var(--accent-blue);
}

.task-text {
  font-size: 14px;
  color: var(--text-secondary);
  line-height: 1.5;
}

.task-item.is-done .task-text {
  color: var(--text-muted);
  text-decoration: line-through;
  text-decoration-thickness: 1px;
  text-decoration-color: rgba(138, 151, 168, 0.6);
}

/* Tags */
.tags-wrap {
  display: flex;
  flex-wrap: wrap;
  gap: 5px;
}

.tag {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  padding: 3px 9px;
  border-radius: 20px;
  border: 1px solid transparent;
  white-space: nowrap;
  letter-spacing: 0.02em;
}

.tag-python {
  background: var(--tag-python-bg);
  color: var(--tag-python-color);
  border-color: rgba(52, 211, 153, 0.2);
}
.tag-dl {
  background: var(--tag-dl-bg);
  color: var(--tag-dl-color);
  border-color: rgba(91, 156, 246, 0.2);
}
.tag-llm {
  background: var(--tag-llm-bg);
  color: var(--tag-llm-color);
  border-color: rgba(245, 158, 11, 0.2);
}
.tag-mlops {
  background: var(--tag-mlops-bg);
  color: var(--tag-mlops-color);
  border-color: rgba(167, 139, 250, 0.2);
}
.tag-cv {
  background: var(--tag-cv-bg);
  color: var(--tag-cv-color);
  border-color: rgba(251, 113, 133, 0.2);
}
.tag-sysdesign {
  background: var(--tag-sys-bg);
  color: var(--tag-sys-color);
  border-color: rgba(45, 212, 191, 0.2);
}
.tag-project {
  background: var(--tag-proj-bg);
  color: var(--tag-proj-color);
  border-color: rgba(251, 146, 60, 0.2);
}
.tag-revision {
  background: var(--tag-rev-bg);
  color: var(--tag-rev-color);
  border-color: rgba(78, 90, 106, 0.2);
}

/* Resources */
.resource-link {
  display: flex;
  align-items: center;
  gap: 7px;
  color: var(--text-secondary);
  text-decoration: none;
  font-size: 13px;
  padding: 4px 0;
  border-radius: var(--radius-sm);
  transition: color 0.15s;
}

.resource-link:hover {
  color: var(--accent-blue);
}

.resource-link::before {
  content: "↗";
  font-size: 12px;
  color: var(--accent-blue);
  opacity: 0.7;
  flex-shrink: 0;
}

/* Hours */
.hrs-badge {
  font-family: var(--font-mono);
  font-size: 13px;
  font-weight: 600;
  color: var(--accent-teal);
  white-space: nowrap;
}

/* ===== FOOTER ===== */
.site-footer {
  position: relative;
  z-index: 1;
  text-align: center;
  padding: 24px 32px 40px;
  font-size: 13px;
  color: var(--text-muted);
  border-top: 1px solid var(--border-subtle);
}

/* ===== SCROLLBAR ===== */
::-webkit-scrollbar {
  width: 6px;
  height: 6px;
}
::-webkit-scrollbar-track {
  background: var(--bg-base);
}
::-webkit-scrollbar-thumb {
  background: var(--border-strong);
  border-radius: 3px;
}
::-webkit-scrollbar-thumb:hover {
  background: var(--text-muted);
}

/* ===== RESPONSIVE ===== */
@media (max-width: 768px) {
  .header-inner {
    padding: 12px 16px;
  }
  .header-stats {
    display: none;
  }
  .toolbar-inner {
    padding: 10px 16px;
  }
  .main-content {
    padding: 16px 8px 48px;
  }
}

/* ===== LOGO STACK + ROADMAP SWITCH ===== */
.logo-stack {
  display: flex;
  flex-direction: column;
  align-items: flex-start;
  gap: 2px;
}

.logo-sub {
  font-size: 12px;
  font-weight: 500;
  color: var(--text-muted);
  letter-spacing: 0.02em;
}

.roadmap-switch {
  display: inline-flex;
  align-items: center;
  gap: 0;
  padding: 3px;
  border-radius: 999px;
  background: var(--bg-card);
  border: 1px solid var(--border-mid);
  flex-shrink: 0;
}

.switch-opt {
  position: relative;
  z-index: 2;
  border: none;
  background: transparent;
  color: var(--text-muted);
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  letter-spacing: 0.06em;
  padding: 8px 14px;
  border-radius: 999px;
  cursor: pointer;
  transition: color 0.2s ease, background 0.2s ease;
}

.switch-opt:hover {
  color: var(--text-primary);
}

.switch-opt.is-active {
  color: var(--text-primary);
}

.mode-dsa .switch-opt--dsa.is-active,
.mode-ai .switch-opt--ai.is-active {
  background: var(--bg-hover);
  box-shadow: 0 0 0 1px var(--border-strong);
}

/* ===== DUAL PANELS (crossfade) ===== */
.roadmap-panels {
  position: relative;
  min-height: 320px;
}

.roadmap-panel {
  transition: opacity 0.28s ease, transform 0.28s ease, visibility 0.28s;
}

.roadmap-panel:not(.is-active) {
  opacity: 0;
  pointer-events: none;
  position: absolute;
  left: 0;
  right: 0;
  top: 0;
  visibility: hidden;
  transform: translateY(6px);
}

.roadmap-panel.is-active {
  opacity: 1;
  visibility: visible;
  position: relative;
  transform: translateY(0);
}

/* ===== DSA TABLE + DIFFICULTY ===== */
.roadmap-table--dsa {
  min-width: 720px;
}

.col-serial {
  width: 52px;
  text-align: center;
}

.col-problem {
  min-width: 220px;
}

.col-diff {
  width: 110px;
}

.col-link {
  min-width: 160px;
}

.serial-badge {
  font-family: var(--font-mono);
  font-size: 12px;
  font-weight: 600;
  color: var(--text-secondary);
  padding: 2px 8px;
  border-radius: var(--radius-sm);
  background: var(--bg-active);
  border: 1px solid var(--border-subtle);
}

.dsa-topic-heading .topic-count {
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 500;
  opacity: 0.75;
  margin-left: 10px;
  text-transform: none;
  letter-spacing: 0;
}

.dsa-problem-title {
  font-family: var(--font-display);
  font-size: 15px;
  font-weight: 600;
  color: var(--text-primary);
}

.dsa-link {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  font-size: 13px;
  font-weight: 600;
  color: var(--text-accent, var(--accent-blue));
  text-decoration: none;
  padding: 6px 12px;
  border-radius: var(--radius-md);
  background: var(--bg-hover);
  border: 1px solid var(--border-mid);
  transition: background 0.15s, border-color 0.15s, transform 0.15s;
}

.dsa-link:hover {
  background: var(--bg-active);
  border-color: var(--border-strong);
  transform: translateY(-1px);
}

.dsa-link::after {
  content: "↗";
  font-size: 12px;
  opacity: 0.8;
}

.dsa-link-host {
  font-weight: 400;
  font-size: 11px;
  color: var(--text-muted);
}

.tag-diff {
  display: inline-block;
  font-family: var(--font-mono);
  font-size: 11px;
  font-weight: 600;
  padding: 4px 10px;
  border-radius: 20px;
  letter-spacing: 0.04em;
  text-transform: uppercase;
}

.tag-diff--easy {
  background: rgba(0 182 122 / 0.14);
  color: #00b47a;
  border: 1px solid rgba(0 182 122 / 0.28);
}

.tag-diff--medium {
  background: rgba(255 161 22 / 0.12);
  color: #ffa116;
  border: 1px solid rgba(255 161 22 / 0.3);
}

.tag-diff--hard {
  background: rgba(255 55 95 / 0.12);
  color: #ff375f;
  border: 1px solid rgba(255 55 95 / 0.28);
}

.dsa-diff-mobile {
  display: none;
  margin-left: 10px;
  vertical-align: middle;
}

.dsa-row.is-done .dsa-problem-title {
  text-decoration: line-through;
  color: var(--text-muted);
}

.dsa-row.is-done {
  opacity: 0.55;
}

.dsa-row.is-done:hover {
  opacity: 0.85;
}

.filter-group--dsa .filter-btn.tag-diff--easy.active {
  background: rgba(0 182 122 / 0.18);
  color: #00b47a;
  border-color: rgba(0 182 122 / 0.45);
}

.filter-group--dsa .filter-btn.tag-diff--medium.active {
  background: rgba(255 161 22 / 0.15);
  color: #ffa116;
  border-color: rgba(255 161 22 / 0.45);
}

.filter-group--dsa .filter-btn.tag-diff--hard.active {
  background: rgba(255 55 95 / 0.14);
  color: #ff375f;
  border-color: rgba(255 55 95 / 0.4);
}

@media (max-width: 900px) {
  .roadmap-table--dsa .col-diff {
    display: none;
  }
  .dsa-diff-mobile {
    display: inline-block;
  }
}

/* ===== LEETCODE (DSA) THEME ===== */
body.mode-dsa {
  --bg-base: #0d0d0d;
  --bg-surface: #161616;
  --bg-card: #1c1c1c;
  --bg-hover: #242424;
  --bg-active: #2a2a2a;
  --border-subtle: rgba(255, 255, 255, 0.06);
  --border-mid: rgba(255, 255, 255, 0.1);
  --border-strong: rgba(255, 255, 255, 0.16);
  --text-primary: #eff1f3;
  --text-secondary: #9fabba;
  --text-muted: #5c6570;
  --text-accent: #ffa116;
  --accent-blue: #ffa116;
  --accent-teal: #2cbb5d;
  --lc-easy: #00b47a;
  --lc-med: #ffa116;
  --lc-hard: #ff375f;
}

body.mode-dsa .bg-grid {
  background-image: linear-gradient(rgba(255, 161, 22, 0.035) 1px, transparent 1px),
    linear-gradient(90deg, rgba(255, 161, 22, 0.035) 1px, transparent 1px);
}

body.mode-dsa .logo-text {
  background: linear-gradient(135deg, #fff 0%, #ffa116 55%, #ffb84d 100%);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

body.mode-dsa .logo-icon {
  color: #ffa116;
}

body.mode-dsa .ring-fill {
  stroke: #ffa116;
  filter: drop-shadow(0 0 8px rgba(255, 161, 22, 0.45));
}

body.mode-dsa .ring-label span {
  color: #ffa116;
}

body.mode-dsa .search-input:focus {
  border-color: #ffa116;
  box-shadow: 0 0 0 3px rgba(255, 161, 22, 0.12);
}

body.mode-dsa .filter-btn.active {
  background: rgba(255, 161, 22, 0.12);
  color: #ffa116;
  border-color: rgba(255, 161, 22, 0.35);
}

body.mode-dsa .sync-btn--primary {
  background: rgba(255, 161, 22, 0.12);
  color: #ffa116;
  border-color: rgba(255, 161, 22, 0.35);
}

body.mode-dsa .import-textarea:focus {
  border-color: #ffa116;
  box-shadow: 0 0 0 3px rgba(255, 161, 22, 0.1);
}

body.mode-dsa .site-header {
  background: rgba(13, 13, 13, 0.88);
}

body.mode-dsa .toolbar {
  background: rgba(13, 13, 13, 0.92);
}

body.mode-dsa .roadmap-switch {
  border-color: rgba(255, 161, 22, 0.25);
}

body.mode-dsa .dsa-topic-row td {
  background: rgba(255, 161, 22, 0.04);
}

body.mode-dsa .done-checkbox,
body.mode-dsa .task-checkbox,
body.mode-dsa .dsa-done-checkbox {
  accent-color: #ffa116;
}