/* 算法基础课产品页 — 背景与 HydroOJ #panel (#edf0f2) 对齐 */

#panel > .main:has(.course-landing) {
  padding-bottom: 0 !important;
  background: #edf0f2;
}

/* 算法基础课不随视频课落地页上探，避免标题被导航栏挡住 */
#panel > .main:has(.course-landing--alg) {
  padding-top: 24px !important;
}

.course-landing.course-landing--alg {
  margin-top: 0;
}

.theme--dark #panel > .main:has(.course-landing) {
  background: #12100e;
}

.course-landing {
  --cl-bg: #edf0f2;
  --cl-bg-card: #ffffff;
  --cl-bg-panel: #f6f4ef;
  --cl-border: #e8e2d6;
  --cl-border-light: #f0ebe3;
  /* 纸白暖灰 — 仅标题/文案/按钮 token */
  --cl-accent: #b45309;
  --cl-accent-hover: #92400e;
  --cl-accent-dim: rgba(180, 83, 9, 0.1);
  --cl-accent-border: rgba(180, 83, 9, 0.28);
  --cl-accent-gradient-end: #d97706;
  --cl-on-accent: #ffffff;
  --cl-text-primary: #1c1917;
  --cl-text-secondary: #57534e;
  --cl-text-muted: #a8a29e;
  --cl-success: #2d8a47;
  --cl-info: #2563eb;
  --cl-teal: #0d9488;
  --cl-purple: #7c3aed;
  --cl-cta-shadow: rgba(180, 83, 9, 0.28);
  --cl-cta-shadow-hover: rgba(180, 83, 9, 0.42);
  --cl-hero-glow: rgba(212, 138, 12, 0.08);
  --cl-card-shadow: 0 1px 3px rgba(0, 0, 0, 0.04), 0 1px 2px rgba(0, 0, 0, 0.03);
  --cl-card-shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.06), 0 2px 6px rgba(0, 0, 0, 0.04);
  --cl-font-display: "Chakra Petch", "Noto Sans SC", sans-serif;
  --cl-font-body: "Noto Sans SC", sans-serif;
  --cl-font-mono: "JetBrains Mono", monospace;
  --cl-max: 960px;
  --cl-gutter: 32px;

  font-family: var(--cl-font-body);
  color: var(--cl-text-primary);
  background: var(--cl-bg);
  margin: -12px -1000px;
  padding: 0;
  border-radius: 12px;
  overflow: hidden;
}

.theme--dark .course-landing {
  --cl-bg: #12100e;
  --cl-bg-card: #1a1714;
  --cl-bg-panel: #211d18;
  --cl-border: #3d3528;
  --cl-border-light: #2d281f;
  /* 琥珀暗夜 — 仅标题/文案/按钮 token */
  --cl-accent: #ef9f27;
  --cl-accent-hover: #d48a0c;
  --cl-accent-dim: rgba(239, 159, 39, 0.12);
  --cl-accent-border: rgba(239, 159, 39, 0.28);
  --cl-accent-gradient-end: #ffd700;
  --cl-on-accent: #0f0c08;
  --cl-text-primary: #f5e6d0;
  --cl-text-secondary: #a89c8c;
  --cl-text-muted: #6b5a42;
  --cl-success: #3fb950;
  --cl-info: #58a6ff;
  --cl-teal: #2dd4bf;
  --cl-purple: #c084fc;
  --cl-cta-shadow: rgba(239, 159, 39, 0.3);
  --cl-cta-shadow-hover: rgba(239, 159, 39, 0.45);
  --cl-hero-glow: rgba(239, 159, 39, 0.08);
  --cl-card-shadow: 0 1px 3px rgba(0, 0, 0, 0.12), 0 1px 2px rgba(0, 0, 0, 0.08);
  --cl-card-shadow-hover: 0 4px 16px rgba(0, 0, 0, 0.2), 0 2px 6px rgba(0, 0, 0, 0.14);
}

.course-landing *,
.course-landing *::before,
.course-landing *::after {
  box-sizing: border-box;
}

/* ── Animations ── */
@keyframes courseFloat {
  0%, 100% { transform: translateY(0); }
  50% { transform: translateY(-6px); }
}

@keyframes courseShimmer {
  0% { transform: translateX(-100%); }
  100% { transform: translateX(200%); }
}

/* ── Hero ── */
.course-landing__hero {
  position: relative;
  text-align: center;
  padding: 64px var(--cl-gutter) 56px;
  overflow: hidden;
}

.course-landing__hero-inner {
  position: relative;
  z-index: 1;
  max-width: var(--cl-max);
  margin: 0 auto;
}

.course-landing__title {
  font-family: var(--cl-font-display);
  font-size: clamp(34px, 5.5vw, 52px);
  font-weight: 700;
  line-height: 1.15;
  margin: 0 0 12px;
  color: var(--cl-text-primary);
  letter-spacing: -0.5px;
}

.course-landing__title-accent {
  background: linear-gradient(135deg, #7f3b06, #4d300f);
  -webkit-background-clip: text;
  -webkit-text-fill-color: transparent;
  background-clip: text;
}

.theme--dark .course-landing__title-accent {
  background: linear-gradient(135deg, #f7b17a, #fbad56);
  -webkit-background-clip: text;
  background-clip: text;
}

.course-landing__subtitle {
  font-size: 16px;
  color: var(--cl-text-secondary);
  line-height: 1.8;
  margin: 0 auto 32px;
  max-width: 620px;
}

.course-landing__tags {
  display: flex;
  gap: 10px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 36px;
}

.course-landing__tag {
  font-size: 12px;
  padding: 3px 10px;
  border-radius: 6px;
  font-family: var(--cl-font-mono);
  font-weight: 500;
  border: 1px solid var(--cl-border);
  background: var(--cl-bg-panel);
  color: var(--cl-text-secondary);
  letter-spacing: 0.2px;
  transition: border-color 0.25s ease, color 0.25s ease;
}

.course-landing__tag:hover {
  border-color: var(--cl-accent-border);
  color: var(--cl-text-primary);
  transform: none;
}

.course-landing__actions {
  display: flex;
  gap: 14px;
  justify-content: center;
  flex-wrap: wrap;
  margin-bottom: 48px;
}

.course-landing__cta {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 14px 32px;
  border-radius: 10px;
  font-family: var(--cl-font-display);
  font-size: 15px;
  font-weight: 600;
  text-decoration: none;
  transition: transform 0.3s ease, box-shadow 0.3s ease, background 0.3s ease, color 0.3s ease;
}

.course-landing__cta--primary {
  background: linear-gradient(135deg, var(--cl-accent), var(--cl-accent-hover));
  color: var(--cl-on-accent) !important;
  border: none;
  box-shadow: 0 4px 24px var(--cl-cta-shadow);
}

.course-landing__cta--primary:hover {
  transform: translateY(-2px);
  box-shadow: 0 8px 32px var(--cl-cta-shadow-hover);
  color: var(--cl-on-accent);
}

.course-landing__cta--secondary {
  background: transparent;
  color: var(--cl-accent);
  border: 1px solid var(--cl-accent);
  font-weight: 500;
}

.course-landing__cta--secondary:hover {
  background: var(--cl-accent-dim);
  transform: translateY(-2px);
  color: var(--cl-accent);
  box-shadow: none;
}

.course-landing__stats {
  display: flex;
  gap: 48px;
  justify-content: center;
  flex-wrap: wrap;
}

.course-landing__stat-value {
  font-family: var(--cl-font-display);
  font-size: 28px;
  font-weight: 700;
  color: var(--cl-text-primary);
  letter-spacing: -0.5px;
}

.course-landing__stat-label {
  font-size: 13px;
  color: var(--cl-text-muted);
  margin-top: 2px;
  letter-spacing: 0.1px;
}

/* ── Hero polish（/course 专用，压过 video_course_landing 同名选择器） ── */
.course-landing--alg .course-landing__hero {
  min-height: 0;
  display: block;
  padding: 72px var(--cl-gutter) 52px;
}

.course-landing--alg .course-landing__hero-inner {
  max-width: 640px;
}

.course-landing--alg .course-landing__title {
  font-size: clamp(36px, 5vw, 48px);
  font-weight: 700;
  margin: 0 0 14px;
  letter-spacing: -0.6px;
}

.course-landing--alg .course-landing__title-accent {
  color: var(--cl-accent);
  background: none;
  -webkit-text-fill-color: unset;
  background-clip: unset;
}

.theme--dark .course-landing--alg .course-landing__title-accent {
  color: var(--cl-accent);
  background: none;
  -webkit-text-fill-color: unset;
  background-clip: unset;
}

.course-landing--alg .course-landing__subtitle {
  font-size: 16px;
  line-height: 1.75;
  margin: 0 auto 24px;
  max-width: 540px;
  color: var(--cl-text-secondary);
}

.course-landing--alg .course-landing__subtitle strong {
  color: var(--cl-accent);
  font-weight: 600;
}

.course-landing--alg .course-landing__tags {
  gap: 8px;
  margin-bottom: 28px;
}

.course-landing--alg .course-landing__tag {
  font-family: var(--cl-font-body);
  font-size: 12px;
  font-weight: 500;
  line-height: 1.4;
  padding: 6px 13px;
  border-radius: 999px;
  border: 1px solid var(--cl-accent-border);
  background: var(--cl-accent-dim);
  color: var(--cl-accent);
  letter-spacing: 0.15px;
  transition: background 0.2s ease, border-color 0.2s ease, color 0.2s ease;
}

.course-landing--alg .course-landing__tag:hover {
  background: color-mix(in srgb, var(--cl-accent) 16%, var(--cl-bg-card));
  border-color: color-mix(in srgb, var(--cl-accent) 42%, var(--cl-border));
  color: var(--cl-accent-hover);
}

.course-landing--alg .course-landing__actions {
  margin-bottom: 32px;
}

.course-landing--alg .course-landing__cta {
  min-height: 44px;
  padding: 12px 28px;
  border-radius: 12px;
}

.course-landing--alg .course-landing__cta--primary {
  background: var(--cl-accent);
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.06), 0 6px 16px var(--cl-cta-shadow);
}

.course-landing--alg .course-landing__cta--primary:hover {
  background: var(--cl-accent-hover);
  transform: translateY(-1px);
  box-shadow: 0 2px 4px rgba(15, 23, 42, 0.06), 0 8px 20px var(--cl-cta-shadow-hover);
}

.course-landing--alg .course-landing__cta--primary:focus-visible {
  outline: 2px solid var(--cl-accent);
  outline-offset: 3px;
}

.course-landing--alg .course-landing__stats {
  gap: 0;
  align-items: stretch;
}

.course-landing--alg .course-landing__stats > div {
  position: relative;
  min-width: 120px;
  padding: 0 32px;
}

.course-landing--alg .course-landing__stats > div + div::before {
  content: "";
  position: absolute;
  left: 0;
  top: 50%;
  width: 1px;
  height: 32px;
  background: var(--cl-border);
  transform: translateY(-50%);
}

.course-landing--alg .course-landing__stat-value {
  font-size: 26px;
  color: var(--cl-accent);
  letter-spacing: -0.4px;
}

.course-landing--alg .course-landing__stat-label {
  font-size: 13px;
  margin-top: 4px;
}

@media (max-width: 768px) {
  .course-landing--alg .course-landing__hero {
    padding: 48px var(--cl-gutter) 36px;
  }

  .course-landing--alg .course-landing__stats > div {
    min-width: 0;
    padding: 0 22px;
  }
}

/* ── Section ── */
.course-landing__sep {
  max-width: var(--cl-max);
  margin: 0 auto;
  padding: 0 var(--cl-gutter);
}

.course-landing__sep-line {
  height: 1px;
  background: linear-gradient(
    90deg,
    transparent,
    var(--cl-border-light) 20%,
    var(--cl-border) 50%,
    var(--cl-border-light) 80%,
    transparent
  );
}

.course-landing__section {
  max-width: var(--cl-max);
  margin: 0 auto;
  padding: 48px var(--cl-gutter);
}

.course-landing__section-label {
  display: block;
  font-family: var(--cl-font-mono);
  font-size: 11px;
  font-weight: 600;
  color: var(--cl-accent);
  letter-spacing: 3px;
  margin-bottom: 14px;
  text-transform: uppercase;
  opacity: 0.85;
}

.course-landing__section-title {
  font-family: var(--cl-font-display);
  font-size: 30px;
  font-weight: 700;
  color: var(--cl-text-primary);
  margin: 0 0 8px;
  line-height: 1.3;
  letter-spacing: -0.2px;
}

.course-landing__section-desc {
  font-size: 15px;
  color: var(--cl-text-secondary);
  line-height: 1.7;
  margin: 0 0 32px;
}

.course-landing__section-desc a {
  color: var(--cl-accent);
  text-decoration: none;
  font-weight: 500;
  transition: color 0.2s ease;
}

.course-landing__section-desc a:hover {
  color: var(--cl-accent-hover);
}

.course-landing__section-desc--tight {
  margin-bottom: 24px;
}

.course-landing__subhead {
  font-family: var(--cl-font-display);
  font-size: 18px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 24px 0 14px;
  letter-spacing: -0.2px;
}

/* ── Pain points ── */
.course-landing__pain-list {
  list-style: none;
  padding: 0;
  margin: 0 0 24px;
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.course-landing__pain-item {
  display: flex;
  gap: 20px;
  align-items: flex-start;
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 14px;
  padding: 22px 24px;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.3s ease;
}

.course-landing__pain-item:hover {
  border-color: var(--cl-accent-border);
  box-shadow: var(--cl-card-shadow-hover);
  transform: translateY(-1px);
}

.course-landing__pain-mark {
  font-family: var(--cl-font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--cl-text-muted);
  flex-shrink: 0;
  margin-top: 2px;
  background: var(--cl-bg-panel);
  padding: 4px 10px;
  border-radius: 6px;
  border: 1px solid var(--cl-border-light);
  min-width: 38px;
  text-align: center;
}

.course-landing__pain-title {
  font-family: var(--cl-font-display);
  font-size: 16px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 6px;
}

.course-landing__pain-desc {
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.7;
  margin: 0;
}

.course-landing__pain-close {
  font-size: 15px;
  color: var(--cl-text-primary);
  line-height: 1.7;
  margin: 0;
  padding: 18px 24px;
  background: var(--cl-accent-dim);
  border: 1px solid var(--cl-accent-border);
  border-radius: 14px;
  font-weight: 500;
}

/* ── Outcomes ── */
.course-landing__outcomes {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.course-landing__outcome {
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 14px;
  padding: 26px 24px;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.3s ease;
}

.course-landing__outcome:hover {
  border-color: var(--cl-accent-border);
  box-shadow: var(--cl-card-shadow-hover);
  transform: translateY(-2px);
}

.course-landing__outcome-num {
  display: inline-block;
  font-family: var(--cl-font-mono);
  font-size: 13px;
  font-weight: 700;
  color: var(--cl-accent);
  margin-bottom: 12px;
  background: var(--cl-accent-dim);
  padding: 3px 10px;
  border-radius: 6px;
  border: 1px solid var(--cl-accent-border);
}

.course-landing__outcome-title {
  font-family: var(--cl-font-display);
  font-size: 16px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 10px;
}

.course-landing__outcome-desc {
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* ── Chapter mindmap ── */
#chapters {
  max-width: 1180px;
}

.course-landing__mindmap {
  --mm-blue: #5b8ff9;
  --mm-teal: #14a6a0;
  --mm-orange: #f59e0b;
  --mm-lime: #8cbf3f;
  --mm-violet: #8b7ad8;
  --mm-gold: #d9a019;
  --mm-red: #d84f4f;
  --mm-sky: #2d8bd8;
  --mm-green: #6cab3c;
  --mm-rose: #e76f91;
  --mm-cyan: #159e9a;
  --mm-brown: #a26a35;
  --mm-amber: var(--cl-accent);
  --mm-card-w: minmax(340px, 1fr);
  --mm-core-w: 168px;
  position: relative;
  display: grid;
  grid-template-columns: var(--mm-card-w) var(--mm-core-w) var(--mm-card-w);
  grid-template-rows: repeat(6, minmax(52px, auto));
  grid-template-areas:
    "arm-io core arm-dfs"
    "arm-two-pointers core arm-bfs"
    "arm-stack core arm-dp"
    "arm-hash core arm-prefix"
    "arm-sort core arm-greedy"
    "arm-tree core arm-union";
  align-items: center;
  column-gap: 36px;
  row-gap: 15px;
  padding: 8px 0;
  overflow: visible;
  min-height: 600px;
}

.course-landing__mindmap-lines {
  position: absolute;
  inset: 0;
  width: 100%;
  height: 100%;
  pointer-events: none;
  z-index: 1;
  overflow: visible;
}

.course-landing__mindmap-core {
  grid-area: core;
  position: relative;
  z-index: 3;
  width: var(--mm-core-w);
  min-height: 88px;
  justify-self: center;
  align-self: center;
  display: flex;
  flex-direction: column;
  align-items: center;
  justify-content: center;
  gap: 6px;
  text-align: center;
  padding: 16px 14px;
}

.course-landing__mindmap-core-ring {
  position: absolute;
  inset: 0;
  border-radius: 18px;
  background: linear-gradient(135deg, #0f4f94, #123a7a);
  border: 1px solid rgba(255, 255, 255, 0.2);
  box-shadow:
    0 14px 34px rgba(15, 79, 148, 0.22),
    inset 0 1px 0 rgba(255, 255, 255, 0.22);
}

.course-landing__mindmap-core-label {
  position: relative;
  z-index: 1;
  font-family: var(--cl-font-display);
  font-size: 20px;
  font-weight: 700;
  color: #ffffff;
  line-height: 1.15;
  letter-spacing: -0.6px;
}

.course-landing__mindmap-core-subtitle {
  position: relative;
  z-index: 1;
  max-width: 170px;
  color: rgba(255, 255, 255, 0.82);
  font-size: 11px;
  line-height: 1.45;
}

.course-landing__mindmap-arm {
  --mm-color: var(--mm-blue);
  position: relative;
  z-index: 2;
  width: 100%;
  flex-shrink: 0;
}

.course-landing__mindmap-arm--blue { --mm-color: var(--mm-blue); }
.course-landing__mindmap-arm--teal { --mm-color: var(--mm-teal); }
.course-landing__mindmap-arm--orange { --mm-color: var(--mm-orange); }
.course-landing__mindmap-arm--lime { --mm-color: var(--mm-lime); }
.course-landing__mindmap-arm--violet { --mm-color: var(--mm-violet); }
.course-landing__mindmap-arm--gold { --mm-color: var(--mm-gold); }
.course-landing__mindmap-arm--red { --mm-color: var(--mm-red); }
.course-landing__mindmap-arm--sky { --mm-color: var(--mm-sky); }
.course-landing__mindmap-arm--green { --mm-color: var(--mm-green); }
.course-landing__mindmap-arm--rose { --mm-color: var(--mm-rose); }
.course-landing__mindmap-arm--cyan { --mm-color: var(--mm-cyan); }
.course-landing__mindmap-arm--brown { --mm-color: var(--mm-brown); }
.course-landing__mindmap-arm--amber { --mm-color: var(--mm-amber); }

.course-landing__mindmap-arm--io { grid-area: arm-io; justify-self: end; }
.course-landing__mindmap-arm--two-pointers { grid-area: arm-two-pointers; justify-self: end; }
.course-landing__mindmap-arm--stack { grid-area: arm-stack; justify-self: end; }
.course-landing__mindmap-arm--hash { grid-area: arm-hash; justify-self: end; }
.course-landing__mindmap-arm--sort { grid-area: arm-sort; justify-self: end; }
.course-landing__mindmap-arm--tree { grid-area: arm-tree; justify-self: end; }
.course-landing__mindmap-arm--dfs { grid-area: arm-dfs; justify-self: start; }
.course-landing__mindmap-arm--bfs { grid-area: arm-bfs; justify-self: start; }
.course-landing__mindmap-arm--dp { grid-area: arm-dp; justify-self: start; }
.course-landing__mindmap-arm--prefix { grid-area: arm-prefix; justify-self: start; }
.course-landing__mindmap-arm--greedy { grid-area: arm-greedy; justify-self: start; }
.course-landing__mindmap-arm--union { grid-area: arm-union; justify-self: start; }

.course-landing__mindmap-topic {
  position: relative;
  z-index: 2;
  display: grid;
  grid-template-columns: auto minmax(0, 1fr);
  gap: 8px;
  align-items: center;
  width: 100%;
  background: transparent;
  transition: transform 0.25s ease;
}

.course-landing__mindmap-arm--left .course-landing__mindmap-topic {
  grid-template-columns: minmax(0, 1fr) auto;
}

.course-landing__mindmap-arm:hover .course-landing__mindmap-topic {
  transform: translateY(-2px);
}

.course-landing__mindmap-title {
  font-family: var(--cl-font-display);
  display: inline-flex;
  align-items: center;
  gap: 8px;
  min-width: 148px;
  max-width: 210px;
  min-height: 38px;
  padding: 6px 12px 6px 8px;
  border-radius: 12px;
  background: linear-gradient(135deg, var(--mm-color), color-mix(in srgb, var(--mm-color) 78%, #0f172a));
  color: #ffffff;
  box-shadow:
    0 7px 16px color-mix(in srgb, var(--mm-color) 22%, transparent),
    inset 0 1px 0 rgba(255, 255, 255, 0.24);
  font-size: 13.5px;
  font-weight: 700;
  margin: 0;
  letter-spacing: -0.1px;
  line-height: 1.25;
}

.course-landing__mindmap-arm--left .course-landing__mindmap-title {
  justify-self: end;
  order: 2;
}

.course-landing__mindmap-title span {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  width: 26px;
  height: 26px;
  flex: 0 0 26px;
  border-radius: 50%;
  background: rgba(255, 255, 255, 0.92);
  color: var(--mm-color);
  font-family: var(--cl-font-mono);
  font-size: 14px;
  font-weight: 700;
  box-shadow: 0 1px 4px rgba(15, 23, 42, 0.16);
}

.course-landing__mindmap-patterns {
  list-style: none;
  margin: 0;
  padding: 0;
  display: flex;
  flex-direction: row;
  flex-wrap: wrap;
  align-items: center;
  align-content: center;
  justify-content: flex-start;
  gap: 4px 6px;
  min-width: 0;
}

.course-landing__mindmap-arm--left .course-landing__mindmap-patterns {
  justify-content: flex-end;
  order: 1;
}

.course-landing__mindmap-patterns li {
  display: inline-flex;
  align-items: center;
  min-height: 21px;
  max-width: 100%;
  font-size: 10.5px;
  font-weight: 500;
  line-height: 1.25;
  color: var(--cl-text-secondary);
  padding: 3px 9px;
  background: var(--cl-bg-card);
  border: 1px solid color-mix(in srgb, var(--mm-color) 42%, var(--cl-border-light));
  border-radius: 999px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.04);
}

/* ── How to learn ── */
.course-landing__howto {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 14px;
  counter-reset: none;
}

.course-landing__howto-item {
  display: flex;
  gap: 18px;
  align-items: flex-start;
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 14px;
  padding: 24px 26px;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.3s ease, box-shadow 0.3s ease, transform 0.3s ease;
}

.course-landing__howto-item:hover {
  border-color: var(--cl-accent-border);
  box-shadow: var(--cl-card-shadow-hover);
  transform: translateX(3px);
}

.course-landing__howto-num {
  width: 36px;
  height: 36px;
  border-radius: 10px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  font-family: var(--cl-font-mono);
  font-size: 15px;
  font-weight: 700;
  color: var(--cl-accent);
  background: var(--cl-accent-dim);
  border: 1px solid var(--cl-accent-border);
}

.course-landing__howto-title {
  font-family: var(--cl-font-display);
  font-size: 16px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 6px;
}

.course-landing__howto-desc {
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* ── Fit / not fit ── */
.course-landing__fit {
  display: grid;
  grid-template-columns: 1fr 1fr;
  gap: 16px;
}

.course-landing__fit-col {
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 14px;
  padding: 26px 24px;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.3s ease, box-shadow 0.3s ease;
}

.course-landing__fit-col:hover {
  box-shadow: var(--cl-card-shadow-hover);
}

.course-landing__fit-col--yes {
  border-top: 4px solid var(--cl-success);
}

.course-landing__fit-col--no {
  border-top: 4px solid var(--cl-text-muted);
}

.course-landing__fit-heading {
  font-family: var(--cl-font-display);
  font-size: 17px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 14px;
}

.course-landing__fit-list {
  margin: 0;
  padding-left: 20px;
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.8;
}

.course-landing__fit-list li {
  padding-left: 4px;
}

.course-landing__fit-list li + li {
  margin-top: 10px;
}

.course-landing__fit-col--yes .course-landing__fit-list {
  color: var(--cl-text-secondary);
}

/* ── FAQ ── */
.course-landing__faq {
  display: flex;
  flex-direction: column;
  gap: 14px;
}

.course-landing__faq-item {
  position: relative;
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 16px;
  overflow: hidden;
  box-shadow: var(--cl-card-shadow);
  transition:
    border-color 0.3s ease,
    box-shadow 0.3s ease,
    background 0.3s ease;
}

.course-landing__faq-item::before {
  content: "";
  position: absolute;
  left: 0;
  top: 0;
  bottom: 0;
  width: 3px;
  background: transparent;
  border-radius: 16px 0 0 16px;
  transition: background 0.3s ease;
}

.course-landing__faq-item:hover {
  border-color: color-mix(in srgb, var(--cl-accent) 22%, var(--cl-border));
  box-shadow: var(--cl-card-shadow-hover);
}

.course-landing__faq-item.is-open {
  border-color: var(--cl-accent-border);
  background: linear-gradient(
    180deg,
    color-mix(in srgb, var(--cl-accent) 4%, var(--cl-bg-card)) 0%,
    var(--cl-bg-card) 48%
  );
}

.course-landing__faq-item.is-open::before {
  background: linear-gradient(180deg, var(--cl-accent), var(--cl-accent-gradient-end));
}

.course-landing__faq-q {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 16px;
  padding: 20px 22px;
  cursor: pointer;
  list-style: none;
  user-select: none;
  transition: background 0.25s ease;
}

.course-landing__faq-q:hover {
  background: color-mix(in srgb, var(--cl-accent) 5%, transparent);
}

.course-landing__faq-q:focus {
  outline: none;
}

.course-landing__faq-q:focus-visible {
  outline: 2px solid var(--cl-accent);
  outline-offset: -2px;
  border-radius: 16px;
}

.course-landing__faq-q::-webkit-details-marker {
  display: none;
}

.course-landing__faq-q-text {
  flex: 1;
  min-width: 0;
  font-family: var(--cl-font-display);
  font-size: 16px;
  font-weight: 600;
  line-height: 1.45;
  letter-spacing: -0.15px;
  color: var(--cl-text-primary);
}

.course-landing__faq-icon {
  flex-shrink: 0;
  position: relative;
  width: 28px;
  height: 28px;
  border-radius: 50%;
  background: var(--cl-accent-dim);
  border: 1px solid var(--cl-accent-border);
  transition:
    background 0.25s ease,
    border-color 0.25s ease,
    transform 0.3s ease;
}

.course-landing__faq-icon::before,
.course-landing__faq-icon::after {
  content: "";
  position: absolute;
  top: 50%;
  left: 50%;
  width: 10px;
  height: 1.5px;
  border-radius: 1px;
  background: var(--cl-accent);
  transform: translate(-50%, -50%);
  transition: transform 0.28s ease, opacity 0.28s ease;
}

.course-landing__faq-icon::after {
  transform: translate(-50%, -50%) rotate(90deg);
}

.course-landing__faq-item.is-open > .course-landing__faq-q .course-landing__faq-icon {
  background: color-mix(in srgb, var(--cl-accent) 16%, var(--cl-bg-card));
  border-color: color-mix(in srgb, var(--cl-accent) 40%, var(--cl-border));
}

.course-landing__faq-item.is-open > .course-landing__faq-q .course-landing__faq-icon::after {
  opacity: 0;
  transform: translate(-50%, -50%) rotate(90deg) scaleX(0);
}

.course-landing__faq-body {
  height: 0;
  overflow: hidden;
  padding: 0 22px;
  transition: height 0.36s cubic-bezier(0.22, 1, 0.36, 1);
}

/* JS 接管前 / 稳态展开：避免首项闪缩 */
.course-landing__faq-item.is-open > .course-landing__faq-body {
  height: auto;
}

.course-landing__faq-a {
  margin: 0;
  padding: 14px 0 20px;
  border-top: 1px solid var(--cl-border-light);
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.8;
}

@media (prefers-reduced-motion: reduce) {
  .course-landing__faq-body {
    transition: none;
  }
}

/* ── Consult block ── */
.course-landing__banner-actions {
  display: flex;
  justify-content: center;
  flex-wrap: wrap;
  gap: 14px;
  margin-bottom: 32px;
}

.course-landing__consult {
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 28px;
  text-align: left;
  padding-top: 28px;
  border-top: 1px solid var(--cl-border);
  max-width: 560px;
  margin: 0 auto;
}

.course-landing__consult-qr {
  flex-shrink: 0;
  width: 140px;
  height: 140px;
  border-radius: 14px;
  overflow: hidden;
  border: 2px solid var(--cl-border);
  background: #fff;
  box-shadow: var(--cl-card-shadow);
  transition: transform 0.3s ease;
}

.course-landing__consult-qr:hover {
  transform: scale(1.04);
}

.course-landing__consult-qr img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: cover;
}

.course-landing__consult-title {
  font-family: var(--cl-font-display);
  font-size: 17px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 10px;
}

.course-landing__consult-desc {
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.75;
  margin: 0;
}

.course-landing__consult-desc strong {
  color: var(--cl-text-primary);
  font-weight: 600;
}

/* ── Feature cards ── */
#features {
  overflow: visible;
}

.course-landing__features {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
  overflow: visible;
  padding-top: 14px;
  padding-right: 8px;
}

.course-landing__feature {
  position: relative;
  overflow: visible;
  background: linear-gradient(165deg, var(--cl-bg-card) 0%, color-mix(in srgb, var(--cl-bg-card) 92%, var(--cl-bg) 8%) 100%);
  border: 1px solid rgba(0, 0, 0, 0.05);
  border-radius: 16px;
  padding: 20px 18px 24px;
  box-shadow:
    0 1px 2px rgba(0, 0, 0, 0.04),
    0 6px 24px rgba(0, 0, 0, 0.06);
  transition: border-color 0.35s ease, transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.35s ease;
}

.theme--dark .course-landing__feature {
  background: linear-gradient(165deg, var(--cl-bg-card) 0%, color-mix(in srgb, var(--cl-bg-card) 88%, #000 12%) 100%);
  border-color: rgba(255, 255, 255, 0.07);
  box-shadow:
    0 1px 2px rgba(0, 0, 0, 0.2),
    0 8px 28px rgba(0, 0, 0, 0.28);
}

.course-landing__feature:hover {
  border-color: var(--cl-accent-border);
  transform: translateY(-4px);
  box-shadow:
    0 2px 4px rgba(0, 0, 0, 0.04),
    0 12px 36px rgba(0, 0, 0, 0.1),
    0 0 0 1px var(--cl-accent-dim);
}

.theme--dark .course-landing__feature:hover {
  box-shadow:
    0 2px 4px rgba(0, 0, 0, 0.25),
    0 14px 40px rgba(0, 0, 0, 0.35),
    0 0 0 1px var(--cl-accent-dim);
}

.course-landing__feature-body {
  position: relative;
  z-index: 1;
  max-width: 58%;
  padding-right: 6px;
}

.course-landing__feature-icon {
  width: 38px;
  height: 38px;
  border-radius: 12px;
  display: flex;
  align-items: center;
  justify-content: center;
  flex-shrink: 0;
  margin-bottom: 12px;
  box-shadow: 0 2px 8px rgba(0, 0, 0, 0.06);
  transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.course-landing__feature:hover .course-landing__feature-icon {
  transform: scale(1.08);
  box-shadow: 0 4px 12px rgba(0, 0, 0, 0.1);
}

.course-landing__feature-icon svg {
  width: 18px;
  height: 18px;
  stroke: currentColor;
  fill: none;
  flex-shrink: 0;
  stroke-width: 2.2;
}

.course-landing__feature-icon--amber {
  background: var(--cl-accent-dim);
  color: var(--cl-accent);
  border: 1px solid var(--cl-accent-border);
}

.course-landing__feature-icon--blue {
  background: rgba(91, 143, 249, 0.12);
  color: #5b8ff9;
  border: 1px solid rgba(91, 143, 249, 0.22);
}

.course-landing__feature-icon--teal {
  background: rgba(13, 148, 136, 0.1);
  color: var(--cl-teal);
  border: 1px solid rgba(13, 148, 136, 0.25);
}

.course-landing__feature-icon--purple {
  background: rgba(124, 116, 209, 0.12);
  color: #7c74d1;
  border: 1px solid rgba(124, 116, 209, 0.22);
}

.course-landing__feature-icon--indigo {
  background: rgba(79, 70, 229, 0.1);
  color: #4f46e5;
  border: 1px solid rgba(79, 70, 229, 0.25);
}

.course-landing__feature-icon--green {
  background: rgba(43, 164, 113, 0.12);
  color: #2ba471;
  border: 1px solid rgba(43, 164, 113, 0.22);
}

.theme--dark .course-landing__feature-icon--blue {
  background: rgba(88, 166, 255, 0.1);
  border-color: rgba(88, 166, 255, 0.25);
}

.theme--dark .course-landing__feature-icon--teal {
  background: rgba(45, 212, 191, 0.1);
  border-color: rgba(45, 212, 191, 0.25);
}

.theme--dark .course-landing__feature-icon--purple {
  background: rgba(192, 132, 252, 0.1);
  border-color: rgba(192, 132, 252, 0.25);
}

.theme--dark .course-landing__feature-icon--indigo {
  background: rgba(129, 140, 248, 0.1);
  color: #818cf8;
  border-color: rgba(129, 140, 248, 0.25);
}

.theme--dark .course-landing__feature-icon--green {
  background: rgba(74, 222, 128, 0.1);
  color: #4ade80;
  border-color: rgba(74, 222, 128, 0.25);
}

.course-landing__feature-title {
  font-family: var(--cl-font-display);
  font-size: 15px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 6px;
  letter-spacing: -0.2px;
}

.course-landing__feature-desc {
  font-size: 12px;
  color: var(--cl-text-secondary);
  line-height: 1.6;
  margin: 0;
}

.course-landing__feature-visual {
  --cl-visual-rotate: 0deg;
  position: absolute;
  top: -8px;
  right: -6px;
  width: 38%;
  max-width: 100px;
  z-index: 2;
  pointer-events: auto;
  cursor: pointer;
  background: #ffffff;
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 12px;
  padding: 4px;
  overflow: hidden;
  box-shadow:
    0 2px 6px rgba(0, 0, 0, 0.05),
    0 10px 28px rgba(0, 0, 0, 0.12);
  transition: transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.35s ease, opacity 0.2s ease;
}

.course-landing__feature-visual--source-hidden {
  opacity: 0;
  pointer-events: none;
  /* 避免去掉 hidden 时 opacity 0→1 淡入造成交接闪烁 */
  transition: none;
}

.theme--dark .course-landing__feature-visual {
  background: #2a241c;
  border-color: rgba(255, 255, 255, 0.08);
  box-shadow:
    0 2px 6px rgba(0, 0, 0, 0.25),
    0 10px 28px rgba(0, 0, 0, 0.4);
}

.course-landing__feature:nth-child(1) .course-landing__feature-visual {
  --cl-visual-rotate: 4deg;
  transform: rotate(var(--cl-visual-rotate));
}

.course-landing__feature:nth-child(2) .course-landing__feature-visual {
  --cl-visual-rotate: -3deg;
  transform: rotate(var(--cl-visual-rotate));
}

.course-landing__feature:nth-child(3) .course-landing__feature-visual {
  --cl-visual-rotate: 2deg;
  transform: rotate(var(--cl-visual-rotate));
}

.course-landing__feature:hover .course-landing__feature-visual {
  box-shadow:
    0 4px 10px rgba(0, 0, 0, 0.07),
    0 16px 36px rgba(0, 0, 0, 0.14);
}

.theme--dark .course-landing__feature:hover .course-landing__feature-visual {
  box-shadow:
    0 4px 10px rgba(0, 0, 0, 0.3),
    0 16px 36px rgba(0, 0, 0, 0.45);
}

.course-landing__feature:nth-child(1):hover .course-landing__feature-visual {
  transform: rotate(2deg) translateY(-4px);
}

.course-landing__feature:nth-child(2):hover .course-landing__feature-visual {
  transform: rotate(-1deg) translateY(-4px);
}

.course-landing__feature:nth-child(3):hover .course-landing__feature-visual {
  transform: rotate(1deg) translateY(-4px);
}

.course-landing__feature-visual img {
  display: block;
  width: 100%;
  height: auto;
  border-radius: 10px;
}

/* ── Feature visual flyout (FLIP preview) ── */
.course-landing__visual-layer {
  position: fixed;
  inset: 0;
  z-index: 10050;
  pointer-events: none;
}

.course-landing__visual-backdrop {
  position: absolute;
  inset: 0;
  background: rgba(20, 18, 14, 0.28);
  backdrop-filter: blur(10px) saturate(1.15);
  -webkit-backdrop-filter: blur(10px) saturate(1.15);
  opacity: 0;
  transition: opacity 0.32s ease;
  pointer-events: auto;
}

.theme--dark .course-landing__visual-backdrop {
  background: rgba(8, 8, 10, 0.45);
}

.course-landing__visual-layer.is-open .course-landing__visual-backdrop {
  opacity: 1;
}

.course-landing__visual-layer.is-closing .course-landing__visual-backdrop {
  opacity: 0;
}

.course-landing__visual-flyout {
  position: fixed;
  z-index: 1;
  box-sizing: border-box;
  background: #ffffff;
  border: 1px solid rgba(0, 0, 0, 0.06);
  border-radius: 16px;
  padding: 8px;
  overflow: hidden;
  box-shadow:
    0 8px 24px rgba(0, 0, 0, 0.12),
    0 28px 64px rgba(0, 0, 0, 0.22);
  pointer-events: auto;
  cursor: default;
  transform-origin: center center;
  will-change: top, left, width, height, transform;
  transition:
    top 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    left 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    width 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    height 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    transform 0.42s cubic-bezier(0.22, 1, 0.36, 1),
    box-shadow 0.42s ease,
    border-radius 0.42s ease,
    padding 0.42s ease;
}

.theme--dark .course-landing__visual-flyout {
  background: #2a241c;
  border-color: rgba(255, 255, 255, 0.1);
  box-shadow:
    0 8px 24px rgba(0, 0, 0, 0.35),
    0 28px 64px rgba(0, 0, 0, 0.55);
}

.course-landing__visual-layer.is-open .course-landing__visual-flyout {
  border-radius: 20px;
  padding: 10px;
  box-shadow:
    0 12px 32px rgba(0, 0, 0, 0.14),
    0 36px 80px rgba(0, 0, 0, 0.28);
}

.theme--dark .course-landing__visual-layer.is-open .course-landing__visual-flyout {
  box-shadow:
    0 12px 32px rgba(0, 0, 0, 0.4),
    0 36px 80px rgba(0, 0, 0, 0.6);
}

.course-landing__visual-flyout img {
  display: block;
  width: 100%;
  height: 100%;
  object-fit: contain;
  border-radius: 12px;
}

.course-landing__visual-layer.is-open .course-landing__visual-flyout img {
  border-radius: 14px;
}

.course-landing__visual-layer.is-reduced-motion .course-landing__visual-backdrop,
.course-landing__visual-layer.is-reduced-motion .course-landing__visual-flyout {
  transition: none;
}

/* ── Curriculum steps ── */
.course-landing__steps {
  position: relative;
  display: flex;
  flex-direction: column;
  gap: 0;
  list-style: none;
  padding: 0;
  margin: 0;
}

.course-landing__steps::before {
  content: "";
  position: absolute;
  left: 31px;
  top: 32px;
  bottom: 32px;
  width: 2px;
  background: linear-gradient(
    180deg,
    var(--cl-accent-border),
    var(--cl-accent-border) 50%,
    transparent
  );
  border-radius: 1px;
}

.course-landing__step {
  display: flex;
  align-items: flex-start;
  gap: 20px;
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-radius: 14px;
  padding: 24px 26px;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.35s ease, transform 0.35s ease, box-shadow 0.35s ease;
  position: relative;
  margin-bottom: 14px;
}

.course-landing__step:last-child {
  margin-bottom: 0;
}

.course-landing__step:hover {
  border-color: var(--cl-accent-border);
  transform: translateX(4px);
  box-shadow: var(--cl-card-shadow-hover);
}

.course-landing__step-num {
  font-family: var(--cl-font-mono);
  font-size: 14px;
  font-weight: 700;
  color: var(--cl-accent);
  background: var(--cl-accent-dim);
  border: 2px solid var(--cl-accent-border);
  padding: 6px 12px;
  border-radius: 10px;
  flex-shrink: 0;
  position: relative;
  z-index: 1;
  min-width: 44px;
  text-align: center;
}

.course-landing__step-title {
  font-family: var(--cl-font-display);
  font-size: 16px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 6px;
}

.course-landing__step-desc {
  font-size: 14px;
  color: var(--cl-text-secondary);
  line-height: 1.7;
  margin: 0;
}

/* ── Language row ── */
.course-landing__langs {
  display: grid;
  grid-template-columns: repeat(3, 1fr);
  gap: 16px;
}

.course-landing__lang {
  background: var(--cl-bg-card);
  border: 1.5px solid var(--cl-border);
  border-radius: 14px;
  padding: 26px 22px;
  text-align: center;
  box-shadow: var(--cl-card-shadow);
  transition: border-color 0.35s ease, transform 0.35s cubic-bezier(0.34, 1.56, 0.64, 1), box-shadow 0.35s ease;
  position: relative;
  overflow: hidden;
}

.course-landing__lang::before {
  content: "";
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 3px;
  background: linear-gradient(90deg, transparent, var(--cl-accent), transparent);
  opacity: 0;
  transition: opacity 0.35s ease;
}

.course-landing__lang:hover {
  border-color: var(--cl-accent-border);
  transform: translateY(-4px);
  box-shadow: 0 8px 30px var(--cl-accent-dim);
}

.course-landing__lang:hover::before {
  opacity: 1;
}

.course-landing__lang-icon {
  width: 44px;
  height: 44px;
  border-radius: 11px;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 16px;
  transition: transform 0.3s ease;
}

.course-landing__lang:hover .course-landing__lang-icon {
  transform: scale(1.08);
}

.course-landing__lang-icon svg {
  width: 22px;
  height: 22px;
  stroke: currentColor;
  fill: none;
  flex-shrink: 0;
}

.course-landing__lang-icon--cpp {
  background: rgba(37, 99, 235, 0.1);
  color: #2563eb;
  border: 1px solid rgba(37, 99, 235, 0.25);
}

.course-landing__lang-icon--py {
  background: rgba(13, 148, 136, 0.1);
  color: #0d9488;
  border: 1px solid rgba(13, 148, 136, 0.25);
}

.course-landing__lang-icon--java {
  background: rgba(212, 138, 12, 0.1);
  color: #d48a0c;
  border: 1px solid rgba(212, 138, 12, 0.3);
}

.theme--dark .course-landing__lang-icon--cpp {
  background: rgba(88, 166, 255, 0.1);
  color: #58a6ff;
  border-color: rgba(88, 166, 255, 0.25);
}

.theme--dark .course-landing__lang-icon--py {
  background: rgba(45, 212, 191, 0.1);
  color: #2dd4bf;
  border-color: rgba(45, 212, 191, 0.25);
}

.theme--dark .course-landing__lang-icon--java {
  background: rgba(239, 159, 39, 0.1);
  color: #ef9f27;
  border-color: rgba(239, 159, 39, 0.3);
}

.course-landing__lang-name {
  font-family: var(--cl-font-display);
  font-size: 17px;
  font-weight: 600;
  color: var(--cl-text-primary);
  margin: 0 0 8px;
  letter-spacing: -0.2px;
}

.course-landing__lang-desc {
  font-size: 13px;
  color: var(--cl-text-secondary);
  line-height: 1.65;
  margin: 0;
}

/* ── Highlight box ── */
.course-landing__highlight {
  background: var(--cl-bg-card);
  border: 1px solid var(--cl-border);
  border-left: 4px solid var(--cl-accent);
  border-radius: 14px;
  padding: 24px 28px;
  font-size: 15px;
  color: var(--cl-text-secondary);
  line-height: 1.85;
  box-shadow: var(--cl-card-shadow);
}

.course-landing__highlight strong {
  color: var(--cl-text-primary);
  font-weight: 600;
}

/* ── CTA banner ── */
.course-landing__banner {
  background: linear-gradient(160deg, var(--cl-bg-panel), var(--cl-bg-card) 60%);
  border: 1px solid var(--cl-border);
  border-radius: 18px;
  padding: 52px 40px;
  text-align: center;
  position: relative;
  overflow: hidden;
  box-shadow: var(--cl-card-shadow);
}

.course-landing__banner::before {
  content: "";
  position: absolute;
  top: -50%;
  left: -20%;
  width: 300px;
  height: 300px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--cl-hero-glow) 0%, transparent 65%);
  filter: blur(50px);
  pointer-events: none;
}

.course-landing__banner::after {
  content: "";
  position: absolute;
  bottom: -40%;
  right: -15%;
  width: 280px;
  height: 280px;
  border-radius: 50%;
  background: radial-gradient(circle, var(--cl-hero-glow) 0%, transparent 65%);
  filter: blur(50px);
  pointer-events: none;
}

.course-landing__banner-shine {
  position: absolute;
  top: 0;
  left: 0;
  right: 0;
  height: 2px;
  background: linear-gradient(90deg, transparent, var(--cl-accent), transparent);
  opacity: 0.9;
}

.course-landing__banner-title {
  font-family: var(--cl-font-display);
  font-size: 28px;
  font-weight: 700;
  color: var(--cl-text-primary);
  margin: 0 0 10px;
  position: relative;
  z-index: 1;
  letter-spacing: -0.2px;
}

.course-landing__banner-desc {
  font-size: 15px;
  color: var(--cl-text-secondary);
  margin: 0 0 24px;
  line-height: 1.7;
  position: relative;
  z-index: 1;
}

/* ── Fade-in ── */
.course-landing__fade {
  opacity: 0;
  transform: translateY(20px);
  transition: opacity 0.6s cubic-bezier(0.16, 1, 0.3, 1), transform 0.6s cubic-bezier(0.16, 1, 0.3, 1);
}

.course-landing__fade--visible {
  opacity: 1;
  transform: translateY(0);
}

/* ── Responsive ── */
@media (max-width: 960px) {
  .course-landing__features {
    grid-template-columns: 1fr;
  }
}

@media (max-width: 768px) {
  .course-landing {
    --cl-gutter: 20px;
    margin: -8px -8px 0;
  }

  .course-landing.course-landing--alg {
    margin-top: 0;
  }

  .course-landing__hero {
    padding: 44px var(--cl-gutter) 36px;
  }

  .course-landing__features,
  .course-landing__langs,
  .course-landing__outcomes,
  .course-landing__fit {
    grid-template-columns: 1fr;
  }

  .course-landing__feature {
    padding: 20px 18px 24px;
  }

  .course-landing__feature-body {
    max-width: 100%;
    padding-right: 0;
    padding-bottom: 8px;
  }

  .course-landing__feature-visual {
    position: relative;
    top: auto;
    right: auto;
    width: 100%;
    max-width: 220px;
    margin: 0 auto;
    padding: 6px;
    border-radius: 16px;
    box-shadow:
      0 2px 6px rgba(0, 0, 0, 0.05),
      0 8px 24px rgba(0, 0, 0, 0.1);
    transform: none !important;
  }

  .course-landing__feature-visual img {
    border-radius: 12px;
  }

  .course-landing__stats {
    gap: 28px;
  }

  .course-landing__section {
    padding: 36px var(--cl-gutter);
  }

  .course-landing__banner {
    padding: 36px 24px;
    border-radius: 14px;
  }

  .course-landing__consult {
    flex-direction: column;
    text-align: center;
    gap: 20px;
  }

  .course-landing__mindmap-lines {
    display: none;
  }

  .course-landing__mindmap {
    display: flex;
    flex-direction: column;
    gap: 12px;
    min-height: 0;
    padding: 16px 0 12px;
  }

  .course-landing__mindmap-core {
    display: none;
  }

  .course-landing__mindmap-arm {
    width: 100%;
    justify-self: stretch !important;
  }

  .course-landing__mindmap-arm--io { order: 1; }
  .course-landing__mindmap-arm--two-pointers { order: 2; }
  .course-landing__mindmap-arm--stack { order: 3; }
  .course-landing__mindmap-arm--hash { order: 4; }
  .course-landing__mindmap-arm--sort { order: 5; }
  .course-landing__mindmap-arm--tree { order: 6; }
  .course-landing__mindmap-arm--dfs { order: 7; }
  .course-landing__mindmap-arm--bfs { order: 8; }
  .course-landing__mindmap-arm--dp { order: 9; }
  .course-landing__mindmap-arm--prefix { order: 10; }
  .course-landing__mindmap-arm--greedy { order: 11; }
  .course-landing__mindmap-arm--union { order: 12; }

  .course-landing__mindmap-topic,
  .course-landing__mindmap-arm--left .course-landing__mindmap-topic {
    display: flex;
    flex-direction: column;
    align-items: stretch;
    gap: 10px;
    padding: 12px;
    background: var(--cl-bg-card);
    border: 1px solid color-mix(in srgb, var(--mm-color) 24%, var(--cl-border-light));
    border-radius: 14px;
    box-shadow: var(--cl-card-shadow);
  }

  .course-landing__mindmap-title,
  .course-landing__mindmap-arm--left .course-landing__mindmap-title {
    order: 1;
    justify-self: stretch;
    max-width: none;
  }

  .course-landing__mindmap-patterns,
  .course-landing__mindmap-arm--left .course-landing__mindmap-patterns {
    order: 2;
    flex-direction: column;
    flex-wrap: nowrap;
    align-items: flex-start;
    justify-content: flex-start;
  }

  .course-landing__mindmap-arm:hover .course-landing__mindmap-topic {
    transform: none;
  }

  .course-landing__mindmap-patterns li {
    font-size: 12px;
    padding: 6px 10px;
  }

  .course-landing__steps::before {
    left: 24px;
  }

  .course-landing__step {
    padding: 20px 20px;
    gap: 14px;
  }

  .course-landing__step-num {
    min-width: 36px;
    padding: 5px 10px;
    font-size: 13px;
  }

  .course-landing__faq-q {
    padding: 16px 18px;
    gap: 12px;
  }

  .course-landing__faq-q-text {
    font-size: 15px;
  }

  .course-landing__faq-body {
    padding: 0 18px;
  }

  .course-landing__faq-a {
    padding: 12px 0 16px;
    font-size: 13.5px;
  }
}