/* Core Layout & Reset */
* {
    box-sizing: border-box;
}

body {
    font-family: -apple-system, BlinkMacSystemFont, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
    background-color: #f0f2f5;
    color: #1c1e21;
    margin: 0;
    padding: 20px 15px;
}

.container {
    max-width: 820px;
    margin: 0 auto;
}

.container-login {
    max-width: 420px;
    padding-top: 20px;
}

/* Utilities */
.inline-form {
    display: inline;
}

.hidden-element {
    display: none;
}

/* Navigation Bar */
.nav-bar {
    display: flex;
    justify-content: space-between;
    align-items: center;
    background: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    padding: 12px 20px;
    margin-bottom: 20px;
    border: 1px solid #e1e4e8;
}

.nav-title {
    font-size: 1.05rem;
    font-weight: 700;
    color: #2c3e50;
    display: flex;
    align-items: center;
    gap: 8px;
}

.nav-actions {
    display: flex;
    gap: 10px;
    align-items: center;
}

/* Card Component */
.card {
    background: #ffffff;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    padding: 24px;
    margin-bottom: 24px;
    border: 1px solid #e1e4e8;
}

.card-login {
    padding: 28px;
    text-align: center;
}

.card-title {
    margin-top: 0;
    margin-bottom: 16px;
    font-size: 1.25rem;
    color: #2c3e50;
    border-bottom: 2px solid #3498db;
    padding-bottom: 8px;
}

.card-login .card-title {
    margin-bottom: 20px;
}

/* Form Controls & Inputs */
.form-group {
    margin-bottom: 12px;
    text-align: left;
}

.card-login .form-group {
    margin-bottom: 16px;
}

.form-group label {
    display: block;
    font-weight: 600;
    margin-bottom: 4px;
    font-size: 0.85rem;
    color: #4a5568;
}

.card-login .form-group label {
    margin-bottom: 6px;
    font-size: 0.88rem;
}

.form-group input {
    width: 100%;
    padding: 8px 10px;
    border: 1px solid #cbd5e0;
    border-radius: 4px;
    font-size: 0.9rem;
}

.form-control {
    width: 100%;
    padding: 10px 12px;
    border: 1px solid #cbd5e0;
    border-radius: 5px;
    font-size: 1rem;
    text-align: center;
    letter-spacing: 2px;
}

.form-control:focus {
    outline: none;
    border-color: #3498db;
    box-shadow: 0 0 0 3px rgba(52, 152, 219, 0.2);
}

/* Add Link Form */
.add-form {
    display: none;
    gap: 10px;
    margin-bottom: 18px;
    background: #f8fafc;
    padding: 12px;
    border-radius: 6px;
    border: 1px solid #e2e8f0;
}

.add-form.open {
    display: flex;
}

.add-form input {
    padding: 8px 10px;
    border: 1px solid #cbd5e0;
    border-radius: 4px;
    font-size: 0.88rem;
}

.add-form input[name="title"] { flex: 2; }
.add-form input[name="url"] { flex: 3; }
.add-form input[name="sort_order"] { flex: 1; min-width: 80px; }

/* Buttons */
.btn {
    background-color: #3498db;
    color: #ffffff;
    border: none;
    padding: 8px 14px;
    border-radius: 5px;
    cursor: pointer;
    font-weight: 600;
    font-size: 0.88rem;
    text-decoration: none;
    display: inline-block;
}

.btn:hover { background-color: #2980b9; }

.btn-full {
    width: 100%;
    padding: 10px 16px;
    font-size: 0.95rem;
}

.btn-success { background-color: #2ecc71; }
.btn-success:hover { background-color: #27ae60; }

.btn-warning { background-color: #f39c12; }
.btn-warning:hover { background-color: #d68910; }

.btn-danger { background-color: #e74c3c; }
.btn-danger:hover { background-color: #c0392b; }

.btn-secondary { background-color: #718096; }
.btn-secondary:hover { background-color: #4a5568; }

.btn-info { 
    background-color: #3498db; 
    cursor: default; 
    min-width: 35px; 
    text-align: center;
}

.btn-small { 
    padding: 5px 10px; 
    font-size: 0.8rem; 
}

/* Badges & Alerts */
.badge { 
    background: #e2e8f0; 
    color: #2d3748; 
    padding: 4px 10px; 
    border-radius: 12px; 
    font-size: 0.8rem; 
    font-weight: 600; 
}

.error-msg {
    color: #e74c3c;
    margin-top: 14px;
    margin-bottom: 0;
    font-size: 0.88rem;
    font-weight: 600;
}

.alert-error {
    background: #fed7d7;
    color: #c53030;
    padding: 10px 14px;
    border-radius: 5px;
    margin-bottom: 16px;
    font-weight: 600;
    font-size: 0.88rem;
}

.delete-warning {
    color: #e74c3c;
    font-size: 0.9rem;
    margin-bottom: 12px;
}

/* Link List Display */
.link-list { 
    list-style: none; 
    padding: 0; 
    margin: 0; 
}

.link-item {
    padding: 10px 12px;
    border-bottom: 1px solid #edf2f7;
    display: flex;
    align-items: center;
    justify-content: space-between;
    gap: 12px;
}

.link-item:last-child { 
    border-bottom: none; 
}

.link-item a {
    color: #1a0dab;
    font-weight: 600;
    text-decoration: none;
    font-size: 0.95rem;
    word-break: break-all;
}

.link-item a:hover { 
    text-decoration: underline; 
}

.item-actions { 
    display: flex; 
    gap: 6px; 
}

/* Modal Overlay & Card */
.modal-overlay {
    display: none;
    position: fixed;
    top: 0; left: 0; right: 0; bottom: 0;
    background: rgba(0, 0, 0, 0.4);
    align-items: center;
    justify-content: center;
    z-index: 1000;
}

.modal-overlay.active { 
    display: flex; 
}

.modal-card {
    background: #ffffff;
    border-radius: 8px;
    width: 100%;
    max-width: 480px;
    padding: 24px;
    box-shadow: 0 10px 25px rgba(0, 0, 0, 0.15);
    border: 1px solid #e1e4e8;
}

.modal-actions {
    display: flex;
    justify-content: flex-end;
    gap: 10px;
    margin-top: 18px;
}