* {
    box-sizing: border-box;
    font-family: "Segoe UI", sans-serif;
}

body {
    background: #f3f4f6;
    margin: 0;
    padding: 0;
    display: flex;
    justify-content: center;
    align-items: start;
    min-height: 100vh;
}

.container {
    width: 100%;
    max-width: 600px;
    padding: 20px;
}

.card {
    background: white;
    padding: 30px;
    border-radius: 16px;
    box-shadow: 0 8px 24px rgba(0, 0, 0, 0.08);
}

.title {
    font-size: 1.8rem;
    font-weight: bold;
    text-align: center;
    margin-bottom: 24px;
    color: #1d4ed8;
}

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

label {
    font-weight: 600;
    color: #374151;
}

textarea,
input {
    padding: 12px;
    border: 1px solid #d1d5db;
    border-radius: 10px;
    font-size: 1rem;
    transition: border-color 0.2s;
}

textarea:focus,
input:focus {
    outline: none;
    border-color: #2563eb;
    box-shadow: 0 0 0 2px rgba(37, 99, 235, 0.2);
}

button[type="submit"] {
    padding: 14px;
    background-color: #2563eb;
    color: white;
    font-weight: 600;
    border: none;
    border-radius: 10px;
    cursor: pointer;
    transition: background-color 0.2s;
}

button:hover {
    background-color: #1e40af;
}

.result {
    margin-top: 30px;
    text-align: center;
}

.qr-preview {
    margin-top: 16px;
}

.qr-preview img {
    max-width: 100%;
    height: auto;
    border-radius: 10px;
    border: 1px solid #e5e7eb;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.08);
    cursor: pointer;
}

.qr-instruction {
    font-size: 0.9rem;
    color: #6b7280;
    margin-top: 8px;
}

.hidden {
    display: none;
}

.toast {
    position: fixed;
    top: 24px;
    right: 24px;
    background-color: #22c55e;
    color: white;
    padding: 12px 20px;
    border-radius: 8px;
    box-shadow: 0 4px 12px rgba(0, 0, 0, 0.15);
    font-size: 0.95rem;
    z-index: 9999;
    opacity: 0;
    transform: translateY(20px);
    transition: all 0.4s ease;
}

.toast.show {
    opacity: 1;
    transform: translateY(0);
}

.toast.hidden {
    display: none;
}