/* --- Google Font & Global Styles --- */
@import url('https://fonts.googleapis.com/css2?family=Poppins:wght@400;500;600;700&display=swap');

:root {
    --primary-color: #00b894;
    --primary-gradient: linear-gradient(45deg, rgba(45, 52, 54, 0.85), rgba(0, 184, 148, 0.8));
    --card-bg: #ffffff;
    --body-bg: #fdfdfd;
    --text-dark: #2d3436;
    --text-light: #636e72;
    --border-color: #e8e8e8;
    --shadow: 0 18px 40px rgba(45, 52, 54, 0.12);
}

* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Poppins', sans-serif;
    background-color: var(--body-bg);
    background-image: url("data:image/svg+xml,%3Csvg xmlns='http://www.w3.org/2000/svg' width='28' height='49' viewBox='0 0 28 49'%3E%3Cg fill-rule='evenodd'%3E%3Cg id='hexagons' fill='%23e9e9e9' fill-opacity='0.4' fill-rule='nonzero'%3E%3Cpath d='M13.99 9.25l13 7.5v15l-13 7.5L1 31.75v-15l12.99-7.5zM3 17.9v12.7l10.99 6.34 11-6.35V17.9l-11-6.34L3 17.9zM0 15l12.99-7.5L26 15v19L13 41.5 0 34V15z'/%3E%3C/g%3E%3C/g%3E%3C/svg%3E");
    color: var(--text-dark);
    display: flex;
    justify-content: center;
    align-items: center;
    min-height: 100vh;
    padding: 15px;
}

.converter-container {
    width: 100%;
    max-width: 420px;
    display: flex;
    flex-direction: column;
    height: 100%;
}

.converter-card {
    background: var(--card-bg);
    border-radius: 28px;
    box-shadow: var(--shadow);
    overflow: hidden;
    display: flex;
    flex-direction: column;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
}

.converter-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 25px 45px rgba(45, 52, 54, 0.15);
}

.card-header {
    position: relative;
    text-align: left;
    color: white;
    padding: 30px;
    min-height: 150px;
    display: flex;
    flex-direction: column;
    justify-content: center;
}

.header-image {
    position: absolute; top: 0; left: 0;
    width: 100%; height: 100%; object-fit: cover; z-index: 1;
}

.header-overlay {
    position: absolute; top: 0; left: 0;
    width: 100%; height: 100%;
    background: var(--primary-gradient);
    z-index: 2;
}

.card-header h1, .card-header p {
    position: relative; z-index: 3;
    text-shadow: 0 2px 8px rgba(0,0,0,0.3);
}

.card-header h1 { font-size: 2rem; font-weight: 700; }
.card-header p { font-size: 1rem; font-weight: 400; opacity: 0.9; }

.card-body { padding: 30px; }
.form-group { margin-bottom: 25px; }
.form-group label {
    display: block; font-weight: 600;
    color: var(--text-dark); margin-bottom: 10px; font-size: 0.9rem;
}

.select-wrapper { position: relative; }
#currencySelect {
    width: 100%; padding: 15px 45px 15px 20px;
    font-family: 'Poppins', sans-serif; font-size: 1rem; font-weight: 500;
    border: 2px solid var(--border-color); border-radius: 12px;
    background-color: var(--card-bg); appearance: none; cursor: pointer;
    transition: border-color 0.3s, box-shadow 0.3s;
}

#currencySelect:focus {
    outline: none; border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 184, 148, 0.2);
}

.select-wrapper::after {
    content: '▼'; font-size: 12px; color: var(--text-light);
    position: absolute; right: 20px; top: 50%;
    transform: translateY(-50%); pointer-events: none;
}

.input-container {
    display: flex; align-items: center;
    border: 2px solid var(--border-color); border-radius: 12px;
    transition: border-color 0.3s, box-shadow 0.3s;
}

.input-container:focus-within {
    border-color: var(--primary-color);
    box-shadow: 0 0 0 3px rgba(0, 184, 148, 0.2);
}

.currency-symbol {
    font-size: 1.8rem; font-weight: 600; color: var(--text-light);
    padding: 0 20px; min-width: 60px; text-align: center;
}

#numberInput {
    width: 100%; border: none; outline: none;
    padding: 20px 20px 20px 0; font-size: 1.8rem;
    font-family: 'Poppins', sans-serif; color: var(--text-dark);
    font-weight: 600; background: transparent;
}

.result-box {
    background-color: #f1fefb; border-left: 5px solid var(--primary-color);
    padding: 25px; border-radius: 12px; min-height: 120px;
    display: flex; align-items: center; justify-content: center;
    text-align: center; color: var(--text-dark);
    font-weight: 600; font-size: 1.2rem; line-height: 1.6;
    transition: all 0.3s;
}

.result-box.typing {
    color: var(--text-light); font-style: italic; font-weight: 500;
}

.result-box.error {
    border-left-color: #d63031; background-color: #fff2f2; color: #d63031;
}

.app-footer {
    text-align: center; margin-top: auto; padding-top: 30px;
    font-size: 0.9rem; color: var(--text-light);
}