/* ============================================================
   CourserTech — Components
   Buttons · Cards · Forms · Breadcrumbs · Tables · Chips
   ============================================================ */

/* ---------- Buttons ---------- */
.btn {
  display: inline-flex;
  align-items: center;
  justify-content: center;
  gap: 9px;
  padding: 13px 26px;
  border-radius: var(--radius);
  font-weight: 700;
  font-size: var(--fs-sm);
  letter-spacing: 0.02em;
  line-height: 1;
  border: 1.5px solid transparent;
  transition: background var(--transition), color var(--transition),
              border-color var(--transition), transform var(--transition),
              box-shadow var(--transition);
  white-space: nowrap;
}
.btn:active { transform: translateY(1px); }
.btn svg { width: 17px; height: 17px; flex: none; }

.btn-primary {
  background: var(--c-primary);
  color: var(--c-white);
}
.btn-primary:hover {
  background: var(--c-primary-dark);
  box-shadow: var(--shadow-md);
}

.btn-outline {
  border-color: var(--c-primary);
  color: var(--c-primary);
  background: transparent;
}
.btn-outline:hover {
  background: var(--c-primary);
  color: var(--c-white);
}

.btn-light {
  background: var(--c-white);
  color: var(--c-primary-deep);
}
.btn-light:hover {
  background: var(--c-accent-soft);
  color: var(--c-primary-dark);
  box-shadow: var(--shadow-md);
}

.btn-ghost-light {
  border-color: rgba(255, 255, 255, 0.55);
  color: var(--c-white);
  background: rgba(255, 255, 255, 0.06);
}
.btn-ghost-light:hover {
  background: var(--c-white);
  color: var(--c-primary-deep);
}

.btn-sm { padding: 9px 18px; font-size: var(--fs-xs); }
.btn-block { width: 100%; }

/* ---------- Cards ---------- */
.card {
  background: var(--c-white);
  border: 1px solid var(--c-line);
  border-radius: var(--radius-lg);
  padding: 28px;
  transition: transform var(--transition), box-shadow var(--transition),
              border-color var(--transition);
}
.card:hover {
  transform: translateY(-4px);
  box-shadow: var(--shadow-md);
  border-color: rgba(0, 169, 206, 0.45);
}
.card .card-icon {
  width: 52px;
  height: 52px;
  display: flex;
  align-items: center;
  justify-content: center;
  border-radius: 12px;
  background: var(--c-accent-soft);
  color: var(--c-primary);
  margin-bottom: 18px;
  transition: background var(--transition), color var(--transition),
              transform var(--transition);
}
.card:hover .card-icon {
  background: var(--c-primary);
  color: var(--c-white);
  transform: scale(1.05);
}
.card .card-icon svg { width: 26px; height: 26px; }
.card h3 { font-size: var(--fs-h4); margin-bottom: 8px; }
.card p { font-size: var(--fs-sm); color: var(--c-muted); margin: 0; }

/* Icon-tile (standalone, smaller) */
.icon-tile {
  width: 44px; height: 44px;
  flex: none;
  display: flex; align-items: center; justify-content: center;
  border-radius: 10px;
  background: var(--c-accent-soft);
  color: var(--c-primary);
}
.icon-tile svg { width: 22px; height: 22px; }

/* ---------- Chips / tags ---------- */
.chip {
  display: inline-flex;
  align-items: center;
  gap: 6px;
  padding: 5px 12px;
  border-radius: var(--radius-pill);
  background: var(--c-accent-soft);
  color: var(--c-primary-dark);
  font-size: var(--fs-xs);
  font-weight: 700;
}
.chip-plain {
  background: var(--c-bg-soft);
  color: var(--c-muted);
}

/* ---------- Breadcrumbs ---------- */
.breadcrumbs {
  display: flex;
  align-items: center;
  flex-wrap: wrap;
  gap: 8px;
  font-size: var(--fs-xs);
  font-weight: 700;
  letter-spacing: 0.06em;
  text-transform: uppercase;
  color: rgba(255, 255, 255, 0.65);
  margin-bottom: 18px;
}
.breadcrumbs a { color: rgba(255, 255, 255, 0.85); transition: color var(--transition); }
.breadcrumbs a:hover { color: var(--c-accent); }
.breadcrumbs .sep { opacity: 0.5; }

/* ---------- Forms ---------- */
.field { margin-bottom: 18px; }
.field label {
  display: block;
  font-size: var(--fs-sm);
  font-weight: 700;
  color: var(--c-ink);
  margin-bottom: 7px;
}
.field label .req { color: var(--c-danger); }

.field input,
.field select,
.field textarea {
  width: 100%;
  padding: 12px 14px;
  border: 1.5px solid var(--c-line);
  border-radius: var(--radius);
  background: var(--c-white);
  font-size: var(--fs-sm);
  color: var(--c-ink);
  transition: border-color var(--transition), box-shadow var(--transition);
}
.field textarea { min-height: 130px; resize: vertical; }

.field input:focus,
.field select:focus,
.field textarea:focus {
  outline: none;
  border-color: var(--c-primary);
  box-shadow: 0 0 0 3px rgba(0, 91, 140, 0.12);
}
.field .error-msg {
  display: none;
  font-size: var(--fs-xs);
  color: var(--c-danger);
  margin-top: 5px;
}
.field.has-error input,
.field.has-error select,
.field.has-error textarea { border-color: var(--c-danger); }
.field.has-error .error-msg { display: block; }

.form-note {
  font-size: var(--fs-xs);
  color: var(--c-muted);
  margin-top: 12px;
}

.form-status {
  display: none;
  padding: 13px 16px;
  border-radius: var(--radius);
  font-size: var(--fs-sm);
  font-weight: 700;
  margin-bottom: 18px;
}
.form-status.ok {
  display: block;
  background: #E9F7EF;
  color: var(--c-success);
  border: 1px solid #BFE8D0;
}
.form-status.err {
  display: block;
  background: #FBECEA;
  color: var(--c-danger);
  border: 1px solid #F1C6C0;
}

/* ---------- Tables ---------- */
.spec-table { width: 100%; border-collapse: collapse; font-size: var(--fs-sm); }
.spec-table th,
.spec-table td {
  text-align: left;
  padding: 12px 14px;
  border-bottom: 1px solid var(--c-line);
}
.spec-table th {
  width: 38%;
  font-weight: 700;
  color: var(--c-ink);
  background: var(--c-bg-soft);
}
.spec-table tr:last-child td,
.spec-table tr:last-child th { border-bottom: 0; }

/* ---------- Logo strip (text logos) ---------- */
.logo-tile {
  display: flex;
  align-items: center;
  justify-content: center;
  height: 74px;
  border: 1px solid var(--c-line);
  border-radius: var(--radius);
  background: var(--c-white);
  font-weight: 900;
  letter-spacing: 0.04em;
  font-size: var(--fs-lg);
  color: #8A99A5;
  filter: grayscale(1);
  opacity: 0.85;
  transition: filter var(--transition), opacity var(--transition),
              color var(--transition), border-color var(--transition);
  padding-inline: 16px;
  text-align: center;
  line-height: 1.2;
}
.logo-tile:hover {
  filter: none;
  opacity: 1;
  color: var(--c-primary);
  border-color: rgba(0, 91, 140, 0.35);
}

/* ---------- Stat ---------- */
.stat { text-align: center; }
.stat .stat-num {
  font-size: clamp(2rem, 4vw, 2.9rem);
  font-weight: 900;
  color: var(--c-primary);
  line-height: 1.1;
}
.on-dark .stat .stat-num { color: var(--c-accent); }
.stat .stat-label {
  font-size: var(--fs-sm);
  color: var(--c-muted);
  font-weight: 700;
  letter-spacing: 0.04em;
  text-transform: uppercase;
  margin-top: 6px;
}
.on-dark .stat .stat-label { color: rgba(255, 255, 255, 0.7); }

/* ---------- Checklist (✓ lists) ---------- */
.checklist { display: grid; gap: 10px; }
.checklist li {
  position: relative;
  padding-left: 30px;
  font-size: var(--fs-sm);
  color: var(--c-body);
}
.checklist li::before {
  content: "";
  position: absolute;
  left: 0; top: 2px;
  width: 19px; height: 19px;
  border-radius: 50%;
  background: var(--c-accent-soft);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%23005B8C' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E");
  background-size: 11px;
  background-position: center;
  background-repeat: no-repeat;
}
.checklist.on-dark li { color: rgba(255, 255, 255, 0.82); }
.checklist.on-dark li::before {
  background-color: rgba(0, 169, 206, 0.2);
  background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' viewBox='0 0 24 24' fill='none' stroke='%2300A9CE' stroke-width='3.2' stroke-linecap='round' stroke-linejoin='round'%3E%3Cpath d='M20 6 9 17l-5-5'/%3E%3C/svg%3E");
}

/* ---------- Flow diagram (sensor → PLC → SCADA …) ---------- */
.flow {
  display: flex;
  flex-wrap: wrap;
  align-items: center;
  justify-content: center;
  gap: 10px 6px;
}
.flow-node {
  display: flex;
  flex-direction: column;
  align-items: center;
  gap: 8px;
  padding: 14px 16px;
  min-width: 118px;
  text-align: center;
  background: var(--c-white);
  border: 1.5px solid var(--c-line);
  border-radius: var(--radius);
  font-size: var(--fs-xs);
  font-weight: 700;
  color: var(--c-ink);
  transition: border-color var(--transition), transform var(--transition);
}
.flow-node:hover { border-color: var(--c-accent); transform: translateY(-2px); }
.flow-node .flow-ico {
  width: 38px; height: 38px;
  display: flex; align-items: center; justify-content: center;
  border-radius: 9px;
  background: var(--c-accent-soft);
  color: var(--c-primary);
}
.flow-node .flow-ico svg { width: 20px; height: 20px; }
.flow-node small { font-weight: 400; color: var(--c-muted); }
.flow-arrow {
  color: var(--c-accent);
  flex: none;
}
.flow-arrow svg { width: 20px; height: 20px; }

/* Vertical flow (water lifecycle) */
.vflow { display: grid; gap: 0; }
.vflow-step {
  position: relative;
  display: grid;
  grid-template-columns: 46px 1fr;
  gap: 16px;
  padding-bottom: 26px;
}
.vflow-step:last-child { padding-bottom: 0; }
.vflow-step .vflow-dot {
  width: 46px; height: 46px;
  border-radius: 50%;
  background: var(--c-primary);
  color: var(--c-white);
  display: flex; align-items: center; justify-content: center;
  font-weight: 900;
  font-size: var(--fs-sm);
  position: relative;
  z-index: 1;
}
.vflow-step:not(:last-child)::before {
  content: "";
  position: absolute;
  left: 22px;
  top: 46px;
  bottom: 4px;
  width: 2px;
  background: linear-gradient(var(--c-line), var(--c-accent));
}
.vflow-step h4 { margin-bottom: 4px; }
.vflow-step p { font-size: var(--fs-sm); color: var(--c-muted); margin: 0; }

/* ---------- Info item (icon + title + text) ---------- */
.info-item { display: flex; gap: 14px; }
.info-item .icon-tile { margin-top: 2px; }
.info-item h4 { margin-bottom: 4px; }
.info-item p { font-size: var(--fs-sm); color: var(--c-muted); margin: 0; }

/* ---------- Numbered feature ---------- */
.num-feature {
  display: grid;
  grid-template-columns: auto 1fr;
  gap: 16px;
  align-items: start;
}
.num-feature .num {
  font-size: 1.6rem;
  font-weight: 900;
  color: var(--c-accent);
  line-height: 1.2;
}
.num-feature h4 { margin-bottom: 6px; }
.num-feature p { font-size: var(--fs-sm); color: var(--c-muted); margin: 0; }

/* ---------- Image with overlay ---------- */
.img-frame {
  position: relative;
  border-radius: var(--radius-lg);
  overflow: hidden;
}
.img-frame img { width: 100%; height: 100%; object-fit: cover; }
.img-frame .img-badge {
  position: absolute;
  left: 16px; bottom: 16px;
  display: inline-flex;
  align-items: center;
  gap: 8px;
  padding: 8px 14px;
  border-radius: var(--radius-pill);
  background: rgba(5, 46, 66, 0.85);
  color: var(--c-white);
  font-size: var(--fs-xs);
  font-weight: 700;
  backdrop-filter: blur(4px);
}
.img-badge .pulse {
  width: 8px; height: 8px;
  border-radius: 50%;
  background: #4ADE80;
  animation: pulse 2s infinite;
}