/* ========================================
   FROST GREEN — FULLY MODERNIZED
   Snow White + #10B981 (Emerald)
   Hero Background Preserved
   ======================================== */

@import url('https://fonts.googleapis.com/css2?family=Inter:wght@300;400;500;600;700&display=swap');

* {
  margin: 0;
  padding: 0;
  box-sizing: border-box;
}

body {
  font-family: 'Inter', sans-serif;
  background: #F8FFFB;
  color: #1F2937;
  line-height: 1.7;
  overflow-x: hidden;
}

/* === NAVBAR === */
.navbar {
  background: rgba(16, 185, 129, 0.95) !important;
  backdrop-filter: blur(12px);
  -webkit-backdrop-filter: blur(12px);
  border-bottom: 1px solid rgba(255,255,255,0.2);
  padding: 1rem 0;
  transition: all 0.3s ease;
  position: sticky;
  top: 0;
  z-index: 1000;
}

.navbar-brand {
  font-weight: 700;
  font-size: 1.5rem;
  color: white !important;
}

.navbar-brand i {
  color: #ECFDF5;
}

.nav-link {
  color: rgba(255,255,255,0.9) !important;
  font-weight: 500;
  padding: 0.5rem 1rem !important;
  border-radius: 12px;
  transition: all 0.3s ease;
  position: relative;
}

.nav-link:hover, .nav-link.active {
  background: rgba(255,255,255,0.2);
  color: white !important;
  transform: translateY(-2px);
}

.nav-link::after {
  content: '';
  position: absolute;
  bottom: 8px;
  left: 50%;
  width: 0;
  height: 2px;
  background: white;
  transition: all 0.3s ease;
  transform: translateX(-50%);
}

.nav-link.active::after {
  width: 60%;
}

/* === HERO - PRESERVED BACKGROUND === */
.hero {
  height: 100vh;
  background: linear-gradient(rgba(16, 185, 129, 0.85), rgba(16, 185, 129, 0.85)),
              url('https://images.unsplash.com/photo-1509062522246-3755977927d7?ixlib=rb-4.0.3&auto=format&fit=crop&w=1950&q=80') center/cover no-repeat;
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  position: relative;
  overflow: hidden;
}

.hero::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: url('data:image/svg+xml,<svg xmlns="http://www.w3.org/2000/svg" viewBox="0 0 100 100"><circle cx="20" cy="20" r="2" fill="rgba(255,255,255,0.1)"/><circle cx="80" cy="80" r="3" fill="rgba(255,255,255,0.15)"/></svg>') repeat;
  animation: float 20s infinite linear;
  pointer-events: none;
}

@keyframes float {
  from { transform: translateY(0); }
  to { transform: translateY(-100px); }
}

.hero h1 {
  font-size: 3.8rem;
  font-weight: 700;
  text-shadow: 0 4px 15px rgba(0,0,0,0.3);
  animation: fadeUp 1s ease-out;
}

.hero .lead {
  font-size: 1.35rem;
  opacity: 0.95;
  animation: fadeUp 1s ease-out 0.2s both;
}

/* === GLASS FORM CARD === */
.form-card {
  background: rgba(255, 255, 255, 0.92);
  backdrop-filter: blur(14px);
  -webkit-backdrop-filter: blur(14px);
  border: 1px solid rgba(16, 185, 129, 0.2);
  border-radius: 1.8rem;
  padding: 2.5rem;
  box-shadow: 0 15px 35px rgba(16, 185, 129, 0.12);
  transition: all 0.4s ease;
  position: relative;
  overflow: hidden;
}

.form-card::before {
  content: '';
  position: absolute;
  top: 0; left: 0; right: 0; bottom: 0;
  background: linear-gradient(135deg, rgba(16,185,129,0.05), rgba(52,211,153,0.05));
  opacity: 0;
  transition: opacity 0.4s ease;
}

.form-card:hover {
  transform: translateY(-8px);
  box-shadow: 0 25px 50px rgba(16, 185, 129, 0.18);
}

.form-card:hover::before {
  opacity: 1;
}

/* === ICON CIRCLE === */
.icon-circle {
  width: 76px; height: 76px;
  background: linear-gradient(135deg, #10B981, #34D399);
  color: white;
  border-radius: 50%;
  display: flex;
  align-items: center;
  justify-content: center;
  margin: 0 auto 1.5rem;
  box-shadow: 0 12px 28px rgba(16, 185, 129, 0.3);
  transition: all 0.3s ease;
}

.icon-circle i {
  font-size: 1.9rem;
}

.form-card:hover .icon-circle {
  transform: scale(1.12) rotate(8deg);
  box-shadow: 0 16px 35px rgba(16, 185, 129, 0.4);
}

/* === FLOATING INPUTS === */
.form-floating-icon {
  position: relative;
}

.form-floating-icon i {
  position: absolute;
  left: 16px;
  top: 50%;
  transform: translateY(-50%);
  color: #10B981;
  font-size: 1.15rem;
  z-index: 10;
  pointer-events: none;
  transition: color 0.3s ease;
}

.form-floating-icon .modern-input {
  padding-left: 52px !important;
  border-radius: 14px;
  border: 1.8px solid #D1FAE5;
  background: #F0FDF4;
  height: 62px;
  font-size: 1rem;
  transition: all 0.3s ease;
}

.form-floating-icon .modern-input:focus {
  border-color: #10B981;
  box-shadow: 0 0 0 0.25rem rgba(16, 185, 129, 0.22);
  background: white;
}

.form-floating-icon .modern-input:focus + i {
  color: #059669;
}

.form-floating-icon label {
  padding-left: 52px;
  color: #4B5563;
  font-weight: 500;
  font-size: 0.95rem;
}

/* === MODERN BUTTON === */
.btn-modern {
  border-radius: 50px;
  padding: 0.85rem 2.2rem;
  font-weight: 600;
  font-size: 1.05rem;
  background: linear-gradient(135deg, #10B981, #34D399);
  border: none;
  color: white;
  box-shadow: 0 10px 25px rgba(16, 185, 129, 0.3);
  transition: all 0.3s ease;
  position: relative;
  overflow: hidden;
}

.btn-modern:hover {
  transform: translateY(-3px);
  box-shadow: 0 16px 35px rgba(16, 185, 129, 0.4);
}

.btn-modern:active {
  transform: translateY(-1px);
}

/* === AD PROGRESS === */
#adProgress {
  height: 6px;
  background: rgba(255,255,255,0.3);
  border-radius: 3px;
  overflow: hidden;
}

#adProgress .progress-bar {
  background: linear-gradient(90deg, #10B981, #34D399);
  transition: width 0.1s linear;
}

/* === ANIMATIONS === */
@keyframes fadeUp {
  from { opacity: 0; transform: translateY(30px); }
  to { opacity: 1; transform: translateY(0); }
}

@keyframes fadeIn {
  from { opacity: 0; }
  to { opacity: 1; }
}

@keyframes slideUp {
  from { transform: translateY(30px); opacity: 0; }
  to { transform: translateY(0); opacity: 1; }
}

.fade-up { animation: fadeUp 0.8s ease-out both; }
.animate-fade-in { animation: fadeIn 1s ease-out; }
.animate-slide-up { animation: slideUp 0.8s ease-out; }

/* === DASHBOARD CARDS === */
.card {
  background: white;
  border-radius: 16px;
  border: none;
  box-shadow: 0 8px 25px rgba(16, 185, 129, 0.08);
  transition: all 0.3s ease;
  overflow: hidden;
}

.card:hover {
  transform: translateY(-5px);
  box-shadow: 0 20px 40px rgba(16, 185, 129, 0.15);
}

.card-header {
  background: linear-gradient(135deg, #10B981, #34D399);
  color: white;
  border: none;
  font-weight: 600;
  padding: 1rem 1.5rem;
}

.table {
  margin-bottom: 0;
}

.table th {
  background: #ECFDF5;
  color: #065F46;
  font-weight: 600;
  font-size: 0.9rem;
  border: none;
}

.table td {
  vertical-align: middle;
  font-size: 0.95rem;
}

.student-name {
  font-weight: 600;
  color: #10B981;
}

.score-in {
  max-width: 90px;
  text-align: center;
}

.score-in input {
  border-radius: 10px;
  border: 1.5px solid #D1FAE5;
  padding: 0.4rem 0.6rem;
  font-size: 0.95rem;
  text-align: center;
}

.score-in input:focus {
  border-color: #10B981;
  box-shadow: 0 0 0 0.2rem rgba(16, 185, 129, 0.2);
}

/* === BUTTONS === */
.btn-success {
  background: linear-gradient(135deg, #10B981, #34D399);
  border: none;
  border-radius: 12px;
  padding: 0.5rem 1rem;
  font-weight: 600;
  transition: all 0.3s ease;
}

.btn-success:hover {
  background: linear-gradient(135deg, #059669, #10B981);
  transform: translateY(-2px);
}

.btn-sm {
  padding: 0.35rem 0.75rem;
  font-size: 0.85rem;
}

/* === INPUTS === */
.form-control, .form-select {
  border-radius: 12px;
  border: 1.5px solid #D1FAE5;
  background: #F0FDF4;
  padding: 0.65rem 1rem;
  transition: all 0.3s ease;
}

.form-control:focus, .form-select:focus {
  border-color: #10B981;
  box-shadow: 0 0 0 0.2rem rgba(16, 185, 129, 0.18);
  background: white;
}

input::placeholder {
  color: #9CA3AF;
  font-size: 0.9rem;
}

/* === SELECT STUDENT === */
#selectStudent {
  border-radius: 12px;
  border: 1.5px solid #D1FAE5;
  padding: 0.6rem 1rem;
  font-size: 0.95rem;
  background: #F0FDF4;
}

/* === FOOTER === */
footer {
  background: #065F46;
  color: #D1FAE5;
  padding: 3rem 0;
  margin-top: 5rem;
  font-size: 0.95rem;
}

footer a {
  color: #A7F3D0;
  text-decoration: none;
  transition: color 0.3s ease;
}

footer a:hover {
  color: white;
}

/* === RESPONSIVE === */
@media (max-width: 768px) {
  .hero h1 { font-size: 2.8rem; }
  .hero .lead { font-size: 1.15rem; }
  .form-card { padding: 2rem; }
  .icon-circle { width: 70px; height: 70px; }
  .icon-circle i { font-size: 1.7rem; }
  .score-in { max-width: 70px; }
  .score-in input { font-size: 0.9rem; }
}