/* =========================
   Global Styles
========================= */
*,
*::before,
*::after {
    box-sizing: border-box;
}

body {
    background: linear-gradient(90deg, #2563eb 60%, #1e40af 100%);
    min-height: 100vh;
    font-family: 'Segoe UI', system-ui, -apple-system, BlinkMacSystemFont, sans-serif;
    margin: 0;
    padding: 16px; /* important for small screens */
    display: flex;
    align-items: center;
    justify-content: center;
}

/* =========================
   Form Container
========================= */
.form-container {
    background: #ffffff;
    width: 100%;
    max-width: 500px;
    padding: 24px;
    border-radius: 14px;
    border: 2px solid #000000;
    box-shadow: 0 10px 30px rgba(0, 0, 0, 0.15);
}

/* =========================
   Heading
========================= */
h2 {
    text-align: center;
    color: #1a365d;
    margin-bottom: 20px;
    font-size: 1.6rem;
}

/* =========================
   Form Groups
========================= */
.form-group {
    margin-bottom: 16px;
    display: flex;
    flex-direction: column;
}

/* =========================
   Labels
========================= */
label {
    margin-bottom: 6px;
    color: #2d3a4a;
    font-weight: 500;
    font-size: 0.95rem;
}

/* =========================
   Inputs & Selects
========================= */
input[type="text"],
input[type="email"],
input[type="password"],
input[type="number"],
select {
    padding: 12px;
    border: 1.5px solid #bfc9d9;
    border-radius: 8px;
    font-size: 1rem;
    background: #f9fbfd;
    outline: none;
    transition: border-color 0.2s ease, box-shadow 0.2s ease;
}

/* Focus (keyboard & accessibility friendly) */
input:focus,
select:focus {
    border-color: #2563eb;
    box-shadow: 0 0 0 3px rgba(37, 99, 235, 0.25);
}

/* Validation States */
input.valid,
select.valid {
    border-color: #10b981;
    background: #f0fdf4;
}

input.invalid,
select.invalid {
    border-color: #ef4444;
    background: #fef2f2;
}

/* JS focus highlight */
input.focused,
select.focused {
    background: #e6f0ff;
    box-shadow: 0 0 0 3px rgba(21, 255, 0, 0.4);
}

/* =========================
   Submit Button
========================= */
button[type="submit"] {
    width: 100%;
    padding: 14px;
    background: linear-gradient(90deg, #2563eb 60%, #1e40af 100%);
    color: #ffffff;
    border: none;
    border-radius: 8px;
    font-size: 1.05rem;
    font-weight: 600;
    cursor: pointer;
    margin-top: 10px;
    transition: transform 0.15s ease, box-shadow 0.15s ease, background 0.2s ease;
}

button[type="submit"]:hover {
    background: linear-gradient(90deg, #1e40af 60%, #2563eb 100%);
    box-shadow: 0 6px 14px rgba(0, 0, 0, 0.2);
}

button[type="submit"]:active {
    transform: scale(0.98);
}

/* =========================
   Checkbox (Terms)
========================= */
.form-group.terms {
    flex-direction: row;
    align-items: center;
    gap: 8px;
    font-size: 0.9rem;
}

.form-group.terms input {
    width: 18px;
    height: 18px;
}

/* =========================
   Mobile Optimizations
========================= */
@media (max-width: 480px) {
    h2 {
        font-size: 1.4rem;
    }

    .form-container {
        padding: 20px;
        border-radius: 12px;
    }

    input,
    select,
    button {
        font-size: 1rem;
    }
}