* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
    font-family: 'Segoe UI', Tahoma, Geneva, Verdana, sans-serif;
}

body {
    background-color: #f0f2f5;
    color: #333;
    line-height: 1.6;
    padding: 20px;
    transition: background-color 0.3s ease;
}

.container {
    max-width: 800px;
    margin: 40px auto;
    background: white;
    border-radius: 20px;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.08);
    padding: 40px;
    border: 1px solid #e1e8ed;
}

header {
    text-align: center;
    margin-bottom: 40px;
    padding-bottom: 20px;
    border-bottom: 2px dashed #4a90e2;
}

h1 {
    color: #2d3748;
    font-size: 2.8em;
    margin-bottom: 10px;
}

h1 i {
    color: #4a90e2;
    margin-right: 15px;
}

.subtitle {
    color: #718096;
    font-size: 1.2em;
}

.card {
    background: #f8fafc;
    border-radius: 15px;
    padding: 25px;
    margin-bottom: 30px;
    border-left: 5px solid #4a90e2;
    transition: transform 0.2s ease, box-shadow 0.2s ease;
}

.card:hover {
    transform: translateY(-5px);
    box-shadow: 0 5px 15px rgba(0, 0, 0, 0.05);
}

h2 {
    color: #4a5568;
    margin-bottom: 15px;
    display: flex;
    align-items: center;
}

h2 i {
    margin-right: 10px;
    color: #4a90e2;
}

ul {
    list-style: none;
    padding: 15px 0;
}

li {
    padding: 10px 15px;
    margin-bottom: 8px;
    background: white;
    border-radius: 10px;
    border: 1px solid #e2e8f0;
    display: flex;
    justify-content: space-between;
    align-items: center;
}

.delete-btn {
    background: #fed7d7;
    color: #9b2c2c;
    border: none;
    border-radius: 6px;
    padding: 3px 10px;
    cursor: pointer;
    font-size: 0.9em;
}

.delete-btn:hover {
    background: #feb2b2;
}

.input-area {
    display: flex;
    gap: 10px;
    margin: 20px 0;
}

input {
    flex: 1;
    padding: 12px 15px;
    border: 2px solid #cbd5e0;
    border-radius: 10px;
    font-size: 1em;
    transition: border 0.3s ease;
}

input:focus {
    outline: none;
    border-color: #4a90e2;
}

button {
    padding: 12px 25px;
    background: #4a90e2;
    color: white;
    border: none;
    border-radius: 10px;
    font-weight: bold;
    cursor: pointer;
    font-size: 1em;
    transition: background 0.3s ease;
    display: inline-flex;
    align-items: center;
    justify-content: center;
}

button i {
    margin-right: 8px;
}

button:hover {
    background: #3a7bc8;
}

.hint {
    font-size: 0.9em;
    color: #a0aec0;
    font-style: italic;
    margin-top: 10px;
}

.action-btn {
    background: #38a169;
    margin: 15px 0;
}

.action-btn:hover {
    background: #2f855a;
}

footer {
    text-align: center;
    margin-top: 40px;
    padding-top: 25px;
    border-top: 2px dashed #e2e8f0;
    color: #718096;
    font-size: 0.95em;
}

footer p {
    margin-bottom: 8px;
}