:root {
  --bg: #fafafa;
  --bg-card: #ffffff;
  --bg-header: #4a6fa5;
  --text: #333333;
  --text-invert: #ffffff;
  --accent: #e0e7ff;
  --accent-completed: #c6f6d5;
  --accent-progress: #4caf50;
  --accent-danger: #e53e3e;
}

body.dark {
  --bg: #101319;
  --bg-card: #1a1e27;
  --bg-header: #2b3a55;
  --text: #e4e4e7;
  --text-invert: #f9fafb;
  --accent: #374151;
  --accent-completed: #14532d;
  --accent-progress: #22c55e;
  --accent-danger: #f97373;
}

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

body {
  font-family: system-ui, -apple-system, BlinkMacSystemFont, "Segoe UI", sans-serif;
  margin: 0;
  background: var(--bg);
  color: var(--text);
  transition: background 0.3s ease, color 0.3s ease;
}

/* HEADER */

header {
  background: var(--bg-header);
  color: var(--text-invert);
  padding: 0.75rem 1rem 0.85rem;
  box-shadow: 0 2px 4px rgba(0, 0, 0, 0.15);
}

.header-main {
  display: flex;
  align-items: center;
  justify-content: space-between;
}

.header-actions {
  display: flex;
  align-items: center;
  gap: 0.6rem;
}

.nav-link {
  color: var(--text-invert);
  text-decoration: none;
  font-size: 0.9rem;
  background: rgba(255, 255, 255, 0.15);
  padding: 0.3rem 0.6rem;
  border-radius: 6px;
  transition: background 0.2s ease;
}

.nav-link:hover {
  background: rgba(255, 255, 255, 0.25);
}

#theme-toggle {
  border: none;
  background: transparent;
  color: var(--text-invert);
  font-size: 1.3rem;
  cursor: pointer;
  transition: transform 0.2s ease;
}

#theme-toggle:hover {
  transform: scale(1.1);
}

.header-secondary {
  display: flex;
  align-items: center;
  gap: 0.5rem;
  margin-top: 0.5rem;
  font-size: 0.85rem;
  flex-wrap: wrap;
}

#progress-container {
  flex: 1;
  background: rgba(255, 255, 255, 0.2);
  border-radius: 999px;
  overflow: hidden;
  height: 10px;
}

#progress-bar {
  height: 100%;
  width: 0%;
  background: var(--accent-progress);
  transition: width 0.3s ease;
}

#progress-text {
  min-width: 70px;
}

#reset-btn {
  border: none;
  background: var(--accent-danger);
  color: var(--text-invert);
  padding: 0.3rem 0.7rem;
  border-radius: 999px;
  cursor: pointer;
  font-size: 0.75rem;
}

/* LAYOUT */

main {
  display: flex;
  flex-direction: column;
  padding: 0.75rem;
  gap: 0.75rem;
}

@media (min-width: 700px) {
  main {
    flex-direction: row;
    padding: 1rem;
    gap: 1rem;
  }
}

/* DAY LIST */

#day-list {
  display: flex;
  overflow-x: auto;
  gap: 0.4rem;
  padding-bottom: 0.2rem;
}

@media (min-width: 700px) {
  #day-list {
    flex-direction: column;
    width: 220px;
    max-height: calc(100vh - 120px);
    overflow-y: auto;
  }
}

#day-list button {
  padding: 0.45rem 0.7rem;
  border: none;
  background: var(--accent);
  border-radius: 999px;
  cursor: pointer;
  white-space: nowrap;
  font-size: 0.85rem;
  transition: background 0.2s ease, transform 0.1s ease, box-shadow 0.2s ease, color 0.2s ease;
  position: relative;
}

#day-list button:hover {
  transform: translateY(-1px);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.15);
}

#day-list button.active {
  background: var(--bg-header);
  color: var(--text-invert);
}

#day-list button.completed {
  background: var(--accent-completed);
  text-decoration: line-through;
}

/* LOCKED DAYS */

#day-list button.locked {
  background: #f3f4f6;
  color: #9ca3af;
}

body.dark #day-list button.locked {
  background: #111827;
  color: #6b7280;
}

#day-list button.locked::after {
  content: "🔒";
  position: absolute;
  right: 8px;
  font-size: 0.9rem;
}

/* CONTENT AREA */

#day-content {
  flex: 1;
  background: var(--bg-card);
  padding: 1rem;
  border-radius: 12px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.1);
  min-height: 300px;
  animation: fadeIn 0.25s ease;
}

#day-content h2 {
  margin-top: 0;
  margin-bottom: 0.5rem;
  font-size: 1.1rem;
}

#day-content h3 {
  margin-top: 1rem;
  margin-bottom: 0.3rem;
  font-size: 0.95rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #6b7280;
}

body.dark #day-content h3 {
  color: #9ca3af;
}

#day-content p {
  margin: 0.2rem 0;
  line-height: 1.5;
}

/* BUTTONS */

#complete-btn,
#share-btn {
  margin-top: 0.7rem;
  padding: 0.7rem;
  width: 100%;
  border-radius: 999px;
  border: none;
  cursor: pointer;
  font-size: 0.9rem;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 0.4rem;
  transition: background 0.2s ease, transform 0.1s ease, box-shadow 0.2s ease, color 0.2s ease;
}

#complete-btn {
  background: var(--accent-progress);
  color: var(--text-invert);
}

#complete-btn.disabled {
  background: #9ca3af;
  cursor: not-allowed;
}

#share-btn {
  background: var(--accent);
  color: var(--text);
}

#complete-btn:hover:not(.disabled),
#share-btn:hover {
  transform: translateY(-1px);
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.18);
}

/* VIDEO 

#day-content iframe {
  border-radius: 10px;
  margin-top: 0.4rem;
} */

/* ANIMATIONS */

@keyframes fadeIn {
  from {
    opacity: 0;
    transform: translateY(4px);
  }
  to {
    opacity: 1;
    transform: translateY(0);
  }
}

/* ABOUT PAGE */

#about-content {
  background: var(--bg-card);
  padding: 1.2rem;
  border-radius: 12px;
  box-shadow: 0 1px 3px rgba(15, 23, 42, 0.1);
  line-height: 1.6;
}

#about-content h2 {
  margin-top: 0;
  font-size: 1.3rem;
}

#about-content h3 {
  margin-top: 1.2rem;
  font-size: 1rem;
  text-transform: uppercase;
  letter-spacing: 0.04em;
  color: #6b7280;
}

body.dark #about-content h3 {
  color: #9ca3af;
}

#back-btn {
  color: var(--text-invert);
  text-decoration: none;
  font-size: 0.9rem;
  background: rgba(255, 255, 255, 0.15);
  padding: 0.3rem 0.6rem;
  border-radius: 6px;
}

footer {
  text-align: center;
  padding: 1.2rem 0;
  margin-top: 2rem;
  font-size: 0.9rem;
  color: var(--text);
}

footer a {
  color: var(--bg-header);
  text-decoration: none;
  font-weight: 500;
}

body.dark footer a {
  color: #9bbcff;
}

footer a:hover {
  text-decoration: underline;
}

.share-link {
  cursor: pointer;
}

.share-result {
  margin-left: 0.5rem;
  font-size: 0.85rem;
  color: var(--accent-progress);
}

footer p {
  margin: 0.4rem 0;
}
.start-btn {
  display: inline-block;
  background: var(--accent-progress);
  color: var(--text-invert);
  padding: 0.8rem 1.4rem;
  border-radius: 999px;
  text-decoration: none;
  font-size: 1rem;
  font-weight: 600;
  transition: background 0.2s ease, transform 0.1s ease;
}

.start-btn:hover {
  transform: translateY(-2px);
  background: #3e9d45;
}

/* Video container */
.vid-container {
  max-width: 514px;
  width: 100%;
  margin-left: auto;
  margin-right: auto;
}
.vid-wrapper {
  position: relative;
  overflow: hidden;
  width: 100%;
  padding-top: 56.25%;
} 
.vid-container iframe {
  position: absolute;
  top: 0;
  right: 0;
  bottom: 0;
  left: 0;
}

#day-list button.today {
  border-left: 4px solid var(--accent-color, #4caf50);
  background: rgba(76, 175, 80, 0.15);
  font-weight: bold;
}



.yt-box {

  align-items: center;

}

  #ytFrame::-webkit-scrollbar {
    display: none;
  }