:root {
  --page-background: linear-gradient(180deg, #eef6ff 0%, #dce9fb 100%);
  --artboard-background: #e9f4ff;
  --mobile-max-width: 430px;

  --video-background: #3c3c3c;

  --feature-text: #272e3b;
  --feature-line: rgba(26, 26, 26, 0.15);
  --signature-text: rgba(26, 26, 26, 0.72);
  --feature-gradient: linear-gradient(90deg, #f1ef67 0%, #4ae5e7 100%);
}

* {
  box-sizing: border-box;
}

html,
body {
  margin: 0;
  height: 100%;
}

body {
  overflow: hidden;
  font-family: "PingFang SC", "Microsoft YaHei", sans-serif;
  background: var(--page-background);
}

button {
  font: inherit;
}

img,
video {
  display: block;
  max-width: none;
}

img {
  user-select: none;
  -webkit-user-drag: none;
}

.canvas {
  width: 100%;
  height: 100vh;
  display: grid;
  place-items: start center;
}

/* Mobile artboard */
.artboard {
  position: relative;
  width: 100%;
  height: 100vh;
  margin: 0 auto;
  overflow: hidden;
  display: flex;
  flex-direction: column;
  background: var(--artboard-background) url("./assets/images/background/page-background@2x.png") no-repeat center top;
  background-size: cover;
}

/* Header section */
.header-section {
  position: relative;
  width: 100%;
  height: 190px;
  flex-shrink: 0;
}

.logo {
  position: absolute;
  top: 15px;
  left: 19px;
  width: 32.8%;
  max-width: 123px;
  aspect-ratio: 123 / 27;
}

.title-block {
  position: absolute;
  top: 53px;
  left: 50%;
  transform: translateX(-50%);
  width: 72.5%;
  max-width: 272px;
  aspect-ratio: 272 / 116;
}

/* Video section */
.video-section {
  width: 100%;
  flex-shrink: 0;
  background: var(--video-background);
  display: flex;
}

.course-video {
  width: 100%;
  height: auto;
  aspect-ratio: 16 / 9;
  object-fit: contain;
  background: var(--video-background);
}

.error-message {
  position: absolute;
  top: 50%;
  left: 50%;
  transform: translate(-50%, -50%);
  color: #fff;
  font-size: 14px;
  text-align: center;
  padding: 20px;
  display: none;
  align-items: center;
  justify-content: center;
}

/* Footer section */
.footer-section {
  position: relative;
  flex: 1.1;
  width: 100%;
  display: flex;
  flex-direction: column;
  align-items: center;
  padding-top: 24px;
  overflow: hidden;
}

/* Feature block */
.feature-strip {
  position: relative;
  width: 68.5%;
  max-width: 257px;
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 16px;
  margin-bottom: 20px;
}

.feature-pill {
  width: 100%;
  padding: 8px 16px;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 5px;
  border-radius: 999px;
  background: var(--feature-gradient);
  color: var(--feature-text);
  font-size: 12px;
  line-height: 18px;
  white-space: nowrap;
}

.spark {
  width: 8px;
  height: 8px;
  flex: 0 0 auto;
  background: #1a1a1a;
  clip-path: polygon(50% 0, 63% 37%, 100% 50%, 63% 63%, 50% 100%, 37% 63%, 0 50%, 37% 37%);
}

.signature {
  width: 100%;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 12px;
}

.line {
  width: 37px;
  height: 1px;
  background: var(--feature-line);
}

.name {
  color: #1A1A1A;
  font-weight: 300;
  font-size: 10px;
  line-height: 13px;
  letter-spacing: 6px;
  text-transform: uppercase;
}

/* Character */
.character {
  width: 60.2%;
  max-width: 300px;
  aspect-ratio: 226 / 191;
  margin-top: auto;
  margin-bottom: 18px;
  z-index: 1;
}

.watermark {
  position: absolute;
  bottom: 0; /* 紧贴最底部 */
  left: 0;
  width: 100%;
  height: auto; /* 高度自适应 */
  opacity: 0.48;
  z-index: 0;
}

/* Slight presentation polish on larger mobile previews */
@media (min-width: 421px) {
  .artboard {
    box-shadow:
      0 28px 80px rgba(63, 117, 174, 0.18),
      0 12px 32px rgba(63, 117, 174, 0.1);
  }
}