:root {
  --color-primary: #14B8A6; /* Aqua green for buttons */
  --color-accent: #0EA5E9; /* Sky blue for links */
  --color-bg: #F0FDF4; /* Soft greenish-white */
  --color-surface: #FFFFFF; /* Clean white for content */
  --color-text-primary: #1E293B; /* Slate text */
  --color-text-muted: #6B7280; /* Muted gray text */
  --color-border: #D1D5DB; /* Optional subtle border tone */
  
  /* ---------- States ---------- */
  --color-success: #10B981;
  --color-error: #EF4444;
  --color-warning: #F59E0B;
  --color-info: #3B82F6;

  /* ---------- Shadows ---------- */
  --shadow-sm: 0 1px 2px rgba(0, 0, 0, 0.05);
  --shadow-md: 0 4px 6px rgba(0, 0, 0, 0.1);
  --shadow-lg: 0 10px 15px rgba(0, 0, 0, 0.1);

  /* ---------- Radius ---------- */
  --radius-sm: 4px;
  --radius-md: 8px;
  --radius-lg: 12px;
}

/* ---------- Base Styles ---------- */
body {
  background-color: var(--color-bg);
  color: var(--color-text-primary);
  font-family: 'Inter', 'Roboto', sans-serif;
  line-height: 1.6;
  margin: 0;
  padding: 0;
}

/* ---------- Components ---------- */
.card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  box-shadow: var(--shadow-sm);
  padding: 1.5rem;
}

.input {
  border: 1px solid var(--color-border);
  border-radius: var(--radius-sm);
  padding: 0.5rem 0.75rem;
  color: var(--color-text-primary);
  background: var(--color-surface);
}

.input:focus {
  border-color: var(--color-primary);
  outline: none;
}

.link {
  text-decoration: none;
  color: inherit;
}

.error {
  color: var(--color-error);
  text-align: center;
}

.nav {
    display: flex;
    justify-content: space-between;
    align-items: center;
    padding: 16px 24px;
    background: var(--color-surface);
    box-shadow: var(--shadow-sm);
  }
  
  .logo {
    display: flex;
    align-items: center;
    gap: 8px;
    font-weight: 600;
    font-size: 18px;
  }
  
  .accent {
    color: var(--color-primary);
  }
  
  .list {
    display: flex;
    gap: 12px;
    list-style: none;
    margin: 0;
    padding: 0;
    align-items: center;
  }
  
  .btn, .register-btn {
    padding: 8px 20px;
    border: none;
    border-radius: var(--radius-md);
    font-weight: 500;
    cursor: pointer;
    transition: all 0.2s ease;
  }
  
  .register-btn {
    display: flex;
    align-items: center;
    justify-content: center;
    background: var(--color-surface);
    color: var(--color-primary);
    border: 1px solid var(--color-primary);
  }
  
  .register-btn:hover {
    background: var(--color-bg);
  }
  
  .btn {
    background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
    color: white;
  }
  
  .btn:hover {
    box-shadow: var(--shadow-md);
    transform: translateY(-1px);
  }

.sidebar-header {
  padding: 24px 20px;
  border-bottom: 1px solid var(--color-border);
}

.sidebar-logo {
  display: flex;
  align-items: center;
  gap: 12px;
  text-decoration: none;
  color: var(--color-text-primary);
  font-size: 20px;
  font-weight: 600;
}

.sidebar-logo img {
  height: 24px;
}

.sidebar-logo .accent {
  color: var(--color-primary);
}

.sidebar-nav {
  flex: 1;
  padding: 24px 12px;
  overflow-y: auto;
}

.sidebar-nav ul {
  list-style: none;
  padding: 0;
  margin: 0;
  display: flex;
  flex-direction: column;
  gap: 8px;
}

.sidebar-nav li a {
  display: flex;
  align-items: center;
  gap: 12px;
  padding: 12px 16px;
  border-radius: var(--radius-md);
  text-decoration: none;
  color: var(--color-text-primary);
  font-weight: 500;
  transition: all 0.2s ease;
}

.sidebar-nav li a:hover {
  background: var(--color-bg);
  color: var(--color-primary);
}

.sidebar-nav li a.active {
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: white;
  box-shadow: var(--shadow-md);
}

.nav-icon {
  width: 20px;
  height: 20px;
  display: flex;
  align-items: center;
  justify-content: center;
}

.sidebar-footer {
  padding: 20px;
  border-top: 1px solid var(--color-border);
  background: var(--color-bg);
}

.user-info {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 12px;
}

.user-avatar {
  width: 40px;
  height: 40px;
  border-radius: 50%;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: white;
  display: flex;
  align-items: center;
  justify-content: center;
  font-weight: 600;
  font-size: 16px;
}

.user-details {
  flex: 1;
}

.user-name {
  font-weight: 600;
  color: var(--color-text-primary);
  font-size: 14px;
  margin: 0;
}

.user-role {
  font-size: 12px;
  color: var(--color-text-muted);
  margin: 0;
}

.logout-btn {
  width: 100%;
  padding: 10px;
  border: none;
  border-radius: var(--radius-md);
  background: var(--color-surface);
  color: var(--color-text-primary);
  font-weight: 500;
  cursor: pointer;
  transition: all 0.2s ease;
  display: flex;
  align-items: center;
  justify-content: center;
  gap: 8px;
  box-shadow: var(--shadow-sm);
}

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

.error-message{
    color: var(--color-error);
}

.form{
    width: 28vw;
    height: max-content;
    padding: 20px;
    position: fixed;
    top: 50%;
    left: 50%;
    padding: 5px;
    background: var(--color-surface);
    transform: translate(-50%, -50%);
    border: 1px solid var(--color-border);
    border-radius: var(--radius-md);
    box-shadow: var(--shadow-lg);
}

.form-heading{
    text-align: center;
    font-size: large;
}

.register-fields {
    display: flex;
    flex-direction: column;
    gap: 8px;
    padding: 12px;
}

.register-fields>.btn{
    width: 40%;
    margin-top: 10px;
    align-self: center;
}
.home-container {
    max-width: 900px;
    margin: 0 auto;
    padding: 4rem 1rem;
    text-align: center;
  }

  .hero-title {
    font-size: 2.5rem;
    font-weight: 700;
    margin-bottom: 1rem;
  }

  .hero-subtitle {
    color: var(--color-text-muted);
    font-size: 1.1rem;
    margin-bottom: 2.5rem;
  }

  .shorten-form {
    display: flex;
    justify-content: center;
    gap: 0.5rem;
    flex-wrap: wrap;
  }

  .shorten-form input {
    width: 60%;
    min-width: 250px;
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: var(--radius-md);
    outline: none;
    font-size: 1rem;
  }

  .shorten-form button {
    background-color: var(--color-primary);
    color: white;
    border: none;
    border-radius: var(--radius-md);
    padding: 0.75rem 1.5rem;
    cursor: pointer;
    transition: background-color 0.2s;
  }

  .shorten-form button:hover {
    background-color: #0d9488;
  }

  .features {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(240px, 1fr));
    gap: 1.5rem;
    margin-top: 4rem;
  }

  .feature-card {
    background-color: var(--color-card-bg);
    border-radius: var(--radius-md);
    padding: 1.5rem;
    box-shadow: 0 4px 10px rgba(0,0,0,0.05);
    transition: transform 0.2s ease;
  }

  .feature-card:hover {
    transform: translateY(-4px);
  }

  .feature-card h3 {
    color: var(--color-accent);
    margin-bottom: 0.5rem;
  }

  .form-container {
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 90vh;
    padding: 1rem;
  }

  .form-card {
    background-color: var(--color-surface);
    width: 100%;
    max-width: 480px;
    padding: 2rem 2.5rem;
    border-radius: var(--radius-lg);
    box-shadow: 0 6px 20px rgba(0, 0, 0, 0.05);
  }

  .form-card h2 {
    font-size: 1.8rem;
    margin-bottom: 0.5rem;
  }

  .subtitle {
    color: var(--color-text-muted);
    margin-bottom: 2rem;
    font-size: 0.95rem;
  }

  .url-form .form-group {
    margin-bottom: 1.5rem;
    text-align: left;
  }

  .url-form label {
    display: block;
    font-weight: 600;
    margin-bottom: 0.5rem;
  }

  .url-form input[type="url"],
  .url-form input[type="text"],
  .url-form input[type="date"] {
    width: 100%;
    padding: 0.75rem 1rem;
    border: 1px solid #d1d5db;
    border-radius: var(--radius-md);
    font-size: 1rem;
    outline: none;
    transition: border-color 0.2s;
  }

  .url-form input:focus {
    border-color: var(--color-primary);
  }

  .checkbox {
    display: flex;
    flex-direction: row;
    align-items: center;
    gap: 0.5rem;
  }

  .generate_qr {
    margin-top: 8px;
  }

  .checkbox label {
    font-weight: normal;
  }

  .submit-btn {
    width: 100%;
    background-color: var(--color-primary);
    color: white;
    font-size: 1rem;
    padding: 0.9rem;
    border: none;
    border-radius: var(--radius-md);
    cursor: pointer;
    transition: background-color 0.2s ease, transform 0.1s ease;
  }

  .submit-btn:hover {
    background-color: #0d9488;
    transform: translateY(-2px);
  }

  .result-container {
  display: flex;
  justify-content: center;
  align-items: center;
  padding: 4rem 1rem;
}

.result-card {
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  padding: 2rem;
  width: 100%;
  max-width: 500px;
  text-align: center;
  box-shadow: 0 4px 8px rgba(0,0,0,0.1);
}

.result-card h2 {
  color: var(--color-primary);
  margin-bottom: 1.5rem;
}

.url-block {
  text-align: left;
  margin-bottom: 1.5rem;
}

.url-block label {
  display: block;
  color: var(--color-muted);
  font-size: 0.9rem;
  margin-bottom: 0.25rem;
}

.original-url {
  color: var(--color-text-primary);
  word-wrap: break-word;
  font-size: 0.95rem;
}

.short-url-box {
  display: flex;
  align-items: center;
  background: var(--color-background);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  overflow: hidden;
}

.short-url-input {
  flex: 1;
  padding: 0.75rem;
  border: none;
  background: transparent;
  color: var(--color-text-primary);
  font-size: 1rem;
}

.copy-btn {
  background: var(--color-primary);
  color: white;
  border: none;
  padding: 0.75rem 1rem;
  cursor: pointer;
  font-weight: 600;
  transition: background 0.2s ease;
}

.copy-btn:hover {
  background: var(--color-accent);
}

.qr-section {
  margin-top: 2rem;
}

.qr-result {
  display: flex;
  flex-direction: column;
  gap: 5px;
}

.qr-section h3 {
  margin-bottom: 0.5rem;
  color: var(--color-muted);
}

.qr-image {
  width: 150px;
  height: 150px;
  border-radius: var(--radius-sm);
  border: 1px solid var(--color-border);
}

.expiration-date {
  margin-top: 1.5rem;
  text-align: left;
}

.expiration-date label {
  display: block;
  color: var(--color-muted);
  font-size: 0.9rem;
  margin-bottom: 0.25rem;
}

.expiration-date-text {
  color: var(--color-text-primary);
  font-size: 0.95rem;
  word-wrap: break-word;
}

.links-container {
  max-width: 1200px;
  margin: 0 auto;
  padding: 40px 20px;
}

.header-section {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 32px;
}

.page-title {
  font-size: 32px;
  font-weight: 700;
  color: var(--color-text-primary);
  margin: 0;
}

.create-link-btn {
  padding: 12px 24px;
  background: linear-gradient(135deg, var(--color-primary), var(--color-accent));
  color: white;
  border: none;
  border-radius: var(--radius-md);
  font-weight: 600;
  cursor: pointer;
  transition: all 0.2s ease;
  box-shadow: var(--shadow-md);
  text-decoration: none;
  display: inline-block;
}

.create-link-btn:hover {
  transform: translateY(-2px);
  box-shadow: var(--shadow-lg);
}

.stats-grid {
  display: grid;
  grid-template-columns: repeat(auto-fit, minmax(200px, 1fr));
  gap: 20px;
  margin-bottom: 32px;
}

.stat-card {
  background: var(--color-surface);
  padding: 20px;
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.stat-label {
  font-size: 14px;
  color: var(--color-text-muted);
  margin-bottom: 8px;
}

.stat-value {
  font-size: 28px;
  font-weight: 700;
  color: var(--color-text-primary);
}

.links-list {
  display: flex;
  flex-direction: column;
  gap: 16px;
}

.link-card {
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  padding: 24px;
  box-shadow: var(--shadow-sm);
  transition: all 0.2s ease;
}

.link-card:hover {
  box-shadow: var(--shadow-md);
  transform: translateY(-2px);
}

.link-header {
  display: flex;
  justify-content: space-between;
  align-items: center;
  margin-bottom: 16px;
}

.link-info {
  flex: 1;
}

.original-url {
  font-size: 16px;
  color: var(--color-text-primary);
  font-weight: 600;
  margin-bottom: 8px;
  word-break: break-all;
}

.short-url-container {
  display: flex;
  align-items: center;
  gap: 12px;
  margin-bottom: 16px;
}

.short-url {
  display: inline-flex;
  align-items: center;
  gap: 8px;
  background: var(--color-bg);
  padding: 8px 16px;
  border-radius: var(--radius-md);
  color: var(--color-accent);
  text-decoration: none;
  font-weight: 500;
  transition: all 0.2s ease;
}

.short-url:hover {
  background: var(--color-primary);
  color: white;
}

.copy-btn {
  display: flex;
  flex-direction: row;
  align-items: center;
  gap: 3px;
  padding: 8px 16px;
  background: var(--color-surface);
  border: 1px solid var(--color-border);
  border-radius: var(--radius-md);
  cursor: pointer;
  transition: all 0.2s ease;
  font-size: 14px;
  font-weight: 500;
  color: var(--color-text-primary);
}

.copy-btn:hover {
  background: var(--color-bg);
  border-color: var(--color-primary);
  color: var(--color-primary);
}

.link-actions {
  display: flex;
  gap: 8px;
}

.action-btn {
  padding: 8px 16px;
  border: none;
  border-radius: var(--radius-md);
  cursor: pointer;
  font-weight: 500;
  font-size: 14px;
  transition: all 0.2s ease;
}

.edit-btn {
  background: var(--color-accent);
  color: white;
}

.edit-btn:hover {
  background: #0284c7;
  transform: translateY(-1px);
}

.delete-btn {
  background: var(--color-error);
  color: white;
}

.delete-btn:hover {
  background: #dc2626;
  transform: translateY(-1px);
}

.qr-btn {
  background: var(--color-success);
  color: white;
}

.qr-btn:hover {
  background: #059669;
  transform: translateY(-1px);
}

.link-meta {
  display: flex;
  flex-wrap: wrap;
  gap: 24px;
  padding-top: 16px;
  border-top: 1px solid var(--color-border);
}

.meta-item {
  display: flex;
  align-items: center;
  gap: 8px;
  font-size: 14px;
  color: var(--color-text-muted);
}

.meta-value {
  font-weight: 600;
  color: var(--color-text-primary);
}

.expired-badge {
  display: inline-block;
  padding: 4px 12px;
  background: var(--color-error);
  color: white;
  border-radius: var(--radius-sm);
  font-size: 12px;
  font-weight: 600;
  margin-left: 8px;
}

.empty-state {
  text-align: center;
  padding: 60px 20px;
  background: var(--color-surface);
  border-radius: var(--radius-lg);
  box-shadow: var(--shadow-sm);
}

.empty-state-title {
  font-size: 24px;
  font-weight: 600;
  color: var(--color-text-primary);
  margin-bottom: 8px;
  margin-top: 0;
}

.empty-state-text {
  color: var(--color-text-muted);
  margin-bottom: 24px;
}

@media (max-width: 768px) {
  .header-section {
    flex-direction: column;
    align-items: flex-start;
    gap: 16px;
  }

  .link-header {
    flex-direction: column;
    gap: 16px;
  }

  .link-actions {
    width: 100%;
    justify-content: space-between;
  }
}

@media (max-width: 768px) {
  .sidebar-container {
    width: 100%;
    height: auto;
    position: relative;
  }
  body {
    margin-left: 0;
  }
}