/* ================================================================
   Courses Page — css/courses.css
   Matches The Web Dev Studio's premium B&W design language.
   ================================================================ */

/* ── Course Grid ── */
.courses-grid {
  display: grid;
  grid-template-columns: repeat(auto-fill, minmax(300px, 1fr));
  gap: 24px;
  margin-top: 8px;
}

/* ── Course Card ── */
.course-card {
  display: flex;
  flex-direction: column;
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 16px;
  overflow: hidden;
  transition: transform .25s ease, box-shadow .25s ease, border-color .25s ease;
  cursor: default;
}

.course-card:hover {
  transform: translateY(-4px);
  box-shadow: 0 12px 40px rgba(0,0,0,.15);
  border-color: var(--border-hover);
}

.course-thumb {
  width: 100%;
  aspect-ratio: 16 / 9;
  object-fit: cover;
  display: block;
  background: var(--bg-primary);
}

.course-thumb-placeholder {
  width: 100%;
  aspect-ratio: 16 / 9;
  display: flex;
  align-items: center;
  justify-content: center;
  background: var(--bg-primary);
  border-bottom: 1px solid var(--border-color);
}

.course-thumb-placeholder-icon {
  font-size: 2.5rem;
  opacity: .18;
}

.course-body {
  padding: 24px;
  display: flex;
  flex-direction: column;
  flex: 1;
  gap: 12px;
}

.course-title {
  font-family: var(--font-title);
  font-size: 1.15rem;
  font-weight: 500;
  color: var(--text-white);
  line-height: 1.35;
  margin: 0;
}

.course-desc {
  font-size: .875rem;
  color: var(--text-secondary);
  line-height: 1.65;
  margin: 0;
  flex: 1;
  display: -webkit-box;
  -webkit-line-clamp: 4;
  -webkit-box-orient: vertical;
  overflow: hidden;
}

.course-enroll-btn {
  margin-top: auto;
  padding: 10px 20px;
  background: var(--text-white);
  color: var(--bg-primary);
  border: 1.5px solid transparent;
  border-radius: 8px;
  font-family: var(--font-body);
  font-size: .85rem;
  font-weight: 500;
  letter-spacing: .01em;
  cursor: pointer;
  transition: background .2s ease, color .2s ease, border-color .2s ease, transform .2s ease;
  width: 100%;
  text-align: center;
}

.course-enroll-btn:hover {
  background: transparent;
  color: var(--text-white);
  border-color: var(--text-white);
  transform: translateY(-1px);
}

/* ── Empty State ── */
.courses-empty {
  text-align: center;
  padding: 80px 20px;
  color: var(--text-muted);
}

.courses-empty-icon {
  font-size: 3rem;
  margin-bottom: 16px;
  opacity: .3;
}

/* ════════════════════════════════════════════════════════════════
   Enrollment Modal
   ════════════════════════════════════════════════════════════════ */
.enroll-overlay {
  position: fixed;
  inset: 0;
  background: rgba(0,0,0,.7);
  backdrop-filter: blur(6px);
  -webkit-backdrop-filter: blur(6px);
  z-index: 8000;
  display: flex;
  align-items: center;
  justify-content: center;
  padding: 20px;
  opacity: 0;
  pointer-events: none;
  transition: opacity .25s ease;
}

.enroll-overlay.active {
  opacity: 1;
  pointer-events: all;
}

.enroll-modal {
  background: var(--bg-secondary);
  border: 1px solid var(--border-color);
  border-radius: 20px;
  padding: 40px 36px;
  width: 100%;
  max-width: 460px;
  position: relative;
  transform: translateY(20px) scale(.97);
  transition: transform .3s cubic-bezier(.16,1,.3,1);
  max-height: 90vh;
  overflow-y: auto;
}

.enroll-overlay.active .enroll-modal {
  transform: translateY(0) scale(1);
}

.enroll-modal-close {
  position: absolute;
  top: 18px;
  right: 20px;
  width: 32px;
  height: 32px;
  border-radius: 8px;
  border: 1px solid var(--border-color);
  background: transparent;
  color: var(--text-secondary);
  display: flex;
  align-items: center;
  justify-content: center;
  cursor: pointer;
  font-size: 1.1rem;
  line-height: 1;
  transition: color .2s ease, border-color .2s ease, background .2s ease;
}

.enroll-modal-close:hover {
  color: var(--text-white);
  border-color: var(--border-hover);
  background: var(--bg-primary);
}

.enroll-modal-header {
  margin-bottom: 28px;
  padding-right: 40px;
}

.enroll-modal-header h3 {
  font-family: var(--font-title);
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--text-white);
  margin: 0 0 6px;
  letter-spacing: -.02em;
}

.enroll-modal-header p {
  font-size: .82rem;
  color: var(--text-secondary);
  margin: 0;
}

/* Step indicator */
.enroll-steps {
  display: flex;
  align-items: center;
  gap: 8px;
  margin-bottom: 28px;
}

.enroll-step-dot {
  width: 8px;
  height: 8px;
  border-radius: 50%;
  background: var(--border-color);
  transition: background .2s ease, transform .2s ease;
  flex-shrink: 0;
}

.enroll-step-dot.active {
  background: var(--text-white);
  transform: scale(1.3);
}

.enroll-step-dot.done {
  background: #4ade80;
}

.enroll-step-line {
  flex: 1;
  height: 1px;
  background: var(--border-color);
}

/* OTP input */
.otp-input {
  text-align: center;
  letter-spacing: .35em;
  font-size: 1.5rem;
  font-weight: 600;
  padding: 14px !important;
}

.otp-timer {
  text-align: center;
  font-size: .78rem;
  color: var(--text-muted);
  margin-top: 10px;
}

/* Error / success banners */
.enroll-msg {
  padding: 12px 16px;
  border-radius: 8px;
  font-size: .82rem;
  margin-bottom: 20px;
  display: none;
}

.enroll-msg.error {
  background: rgba(239,68,68,.12);
  border: 1px solid rgba(239,68,68,.3);
  color: #f87171;
  display: block;
}

.enroll-msg.success {
  background: rgba(74,222,128,.12);
  border: 1px solid rgba(74,222,128,.3);
  color: #4ade80;
  display: block;
}

/* Success state */
.enroll-success-wrap {
  text-align: center;
  padding: 20px 0;
}

.enroll-success-icon {
  width: 64px;
  height: 64px;
  border-radius: 50%;
  background: rgba(74,222,128,.15);
  border: 1.5px solid rgba(74,222,128,.4);
  display: flex;
  align-items: center;
  justify-content: center;
  font-size: 1.8rem;
  margin: 0 auto 20px;
  color: #4ade80;
}

.enroll-success-wrap h3 {
  font-family: var(--font-title);
  font-size: 1.3rem;
  font-weight: 500;
  color: var(--text-white);
  margin: 0 0 8px;
}

.enroll-success-wrap p {
  font-size: .875rem;
  color: var(--text-secondary);
  line-height: 1.6;
  margin: 0;
}

/* ── Responsive ── */
@media (max-width: 768px) {
  .courses-grid {
    grid-template-columns: 1fr;
    gap: 16px;
  }

  .enroll-modal {
    padding: 32px 24px;
    border-radius: 16px;
  }
}

@media (max-width: 480px) {
  .enroll-overlay {
    align-items: flex-end;
    padding: 0;
  }

  .enroll-modal {
    border-radius: 20px 20px 0 0;
    max-height: 95vh;
    max-width: 100%;
  }
}